Prevalence of molar incisor hypomineralization and demands for treatment according to the severity of its clinical manifestation.

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Bianca Mattos Santos Guerra, Roberta Costa Jorge, Patrícia Papoula Gorni dos Reis, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4279100/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 24 Jan, 2025 Read the published version in Clinical Oral Investigations → Version 1 posted 9 You are reading this latest preprint version Abstract Aim Assess the prevalence and severity of molar incisor hypomineralization (MIH) in children 6- to 12-year-old and correlate MIH severity with the complexity of treatment demands. Materials and methods Between March and October 2023, 2,136 children were screened for MIH by two calibrated examiners. MIH severity was categorized in mild, moderate, severe, and very severe. Treatment requirements were categorized in basic, intermediate, and complex. Results The prevalence of MIH was 15.5% (n = 331). Among the 126 children with atypical caries/restoration, cusp involvement was observed in 60.3%, endodontic treatment was necessary in 24.6%, only 15% needed restorations limited to two tooth surfaces with no cusp involvement. Extraction due to MIH was observed in 2.7%. Conclusion The prevalence of MIH was in accordance with previous literature. Whenever a restorative treatment was necessary, it often involved multiple tooth surfaces and cusps. The complexity of treatment demands increased with age. It is necessary that oral health policymakers pay special attention to children with MIH to ensure appropriate treatment. Molar incisor hypomineralization Prevalence Treatment need Figures Figure 1 Figure 2 Introduction Molar incisor hypomineralization (MIH) has been extensively studied since its first description in 2001[ 1 ]. Characterized as a qualitative defect of enamel mineralization, MIH presents clinically as demarcated opacities ranging in color from white-creamy to yellow-brownish affecting at least one first permanent molar often affecting also permanent incisors [ 2 ]. The estimate overall prevalence of MIH is 13.5%, showing no significant geographical difference between continents, with 36.3% of cases classified as moderate to severe[ 3 ]. The asymmetric characteristic of MIH was confirmed by variations in the number of affected FPM and permanent incisors[ 3 ]. The defective enamel has a lower mineral content, is highly porous, and prone to breakdown as soon as it emerges in the oral cavity and is exposed to functional forces[ 4 , 5 ]. The severity of the hypomineralization correlates with the clinical features of the enamel. Yellow-brownish opacities have a higher protein content and decreased mechanical properties than the white-creamy ones[ 6 ]. Therefore, darker opacities are at higher risk of breakdown and progression to the more severe levels of the condition[ 7 ]. MIH has been associated with higher caries prevalence and increased caries index in children[ 8 , 9 ]. The less mineralized enamel and areas where the enamel disintegrates favor caries progression, resulting in atypical caries lesions affecting multiple tooth surfaces. Moreover, tooth surfaces usually not affected by caries, such as free smooth surfaces and cusps, are often carious or filled in the presence of MIH[ 10 ]. Hence, besides the higher caries index, children with MIH might also require more complex restorative treatment. MIH has been shown to significantly increase the global burden of dental treatment needs. In 2015/2016, it was estimated that the proportion of patients in need of care (those with tooth pain, hypersensitivity, or post-eruptive breakdown) was 27.4% or 5 million new treatment cases each year. Much of the burden of MIH relies on low- and middle-income countries, where the access to dental treatment is limited [ 11 ]. Providing oral care for all the affected individuals is highly challenging. Therefore, aside from assessing the prevalence of MIH, it is necessary to provide data about the demands and complexity of the treatment needs, so that oral health policymakers are substantiated to appropriately plan the oral health care strategies. The aim of the present study was to assess the prevalence and severity of MIH in a group of children 6- to 12-year-old and correlate the MIH severity with the complexity of treatment demands. Methods Study design, setting, and participants This was a cross-sectional observational study conducted in the city of Petrópolis, Brazil. Ten public schools were visited to screen patients for a randomized controlled trial (RCT) that will evaluate the clinical performance of restorative treatment for severe MIH molars (registered in REBEC RBR-4mtq8d9). These ten public schools were chosen because the dentists participating in the RCT as operators are affiliated with the local public oral care system, and the schools are situated within the coverage of this system. Hence, the children selected for the RCT can easily be referred to the nearest oral health unit. Petrópolis is situated in the southeast region of Brazil, in the state of Rio de Janeiro, has a population of slightly over 300,000 inhabitants. The Human Development Index is 0.745 and the population has access to artificially fluoridated water according to Brazilian regulations. All children from the 1st to the 7th grades at school were considered eligible and were invited to participate in the study. The study was approved by the Research Ethics Committee of the Pedro Ernesto University Hospital – Rio de Janeiro State University (5.763.553). Participation was voluntary and an informed consent was sent to children’s caregivers. The inclusion criterion was the presence of at least one FPM erupted. Children presenting other developmental enamel defect than MIH ( e.g. , amelogenesis imperfecta, severe fluorosis), chronic health conditions, unable to cooperate with the dental examination, or with orthodontic appliances were excluded. Children who were absent on the day the school was visited were considered as dropouts. MIH detection and severity at the tooth level Between March 2023 and October 2023, two trained and calibrated examiners performed the clinical examinations. First, a screening was conducted in the classrooms with the children seated at their desks and the dentist positioned in front each child. Using a head lamp and wood sticks to gently retract cheeks and tongue, the dentist searched for any signs of suspicious opacities, enamel breakdown, or restorations indicative of MIH according to EAPD criteria[ 12 ]. Children who presented any indicative sign of MIH were referred for a detailed examination in a separate room. Supervised toothbrushing was done prior to the detailed examination. Then, children were seated on regular chairs with a small pillow supporting their heads against the chair back. The dentist was positioned behind the child for a better view of the whole mouth. In addition to the head lamp, the dentist used dental mirror, probe, and cotton rolls if it was necessary to control moisture. The comprehensive mouth examination followed Ghanim[ 13 ] criteria for MIH, differentiating between white-creamy and yellow-brownish opacities (Table 1 ). Other enamel defects besides MIH, i.e. fluorosis and hypoplasia, were also registered but will not be considered in the present study. MIH was registered at the tooth surface level. Trained assistants registered the collected data in datasheets. Table 1 MIH severity classification at the tooth level. Score Description 0 No visible enamel defects. 21 White-creamy opacity (W-OP) 22 Yellow-brownish opacity (Y-OP) 3 Post-eruptive breakdown (PEB) 4 Atypical restoration (AR) 5 Atypical caries (AC) 6 Extracted due to MIH (EXT)* *Teeth extensive coronary disintegration, clearly indicated for extraction were also considered as EXT. MIH severity at the individual level Patients were categorized based on the severity of MIH, determined by the most severe score assigned to at least one tooth. In this classification, scores for AR and AC were combined as AR/AC to indicate both past and present restorative needs. AR/AC was further divided into three categories from the mildest to the most severe conditions: AR/AC involving up to 2 tooth surfaces without cusp or pulp involvement (AR/AC-2surfaces), AR/AC involving cusp and/or 3 or more tooth surfaces with no pulp involvement (AR/AC-cusp), and AR/AC with pulp involvement (AR/AC-pulp). Pulp involvement was assessed according to PUFA criteria[ 14 ]. These severity categories of MIH were then correlated with treatment demands, considering the clinical findings (Table 2 ). The recommendations regarding treatment were based on EAPD guidelines [ 12 ]. Table 2 MIH severity and corresponding treatment recommendation. MIH Treatment Description Severity Modalities Complexity W-OP* Mild Monitoring Basic Y-OP* Mild/Moderate Monitoring or Topical fluoride or remineralizing agents or Sealants Basic PEB (restricted to enamel or exposing hard dentine) Moderate Monitoring or Topical fluoride or remineralizing agents or Sealants or Direct restoration Basic/Intermediate AR/AC (extending up to two tooth surfaces, not involving cups, with no pulp involvement). Severe Direct restoration Intermediate AR/AC cusp (extending to three or more tooth surfaces, involving cusps). Very severe Indirect restoration Complex AR/AC pulp (with pulp involvement). Very severe Endodontic treatment and indirect restoration Complex EXT (extensive coronary disintegration, with pulp involvement, indicated for extraction or extracted due to MIH). Very severe Extraction and/or orthodontic monitoring/orthodontic treatment Complex * W-OP or Y-OP in anterior teeth might be indicative for aesthetic treatment if aesthetics is a concern for the patient. For any of the severity levels, report of hypersensitivity by the patient may increase the level of the treatment demand. Training and calibration The examiners received theoretical and practical training on how to diagnose MIH and to assess pulp involvement by an experienced examiner. The distinction between MIH and other developmental defects of enamel was emphasized during the training process. Calibration exercises were done with a set of 40 clinical photographs to assess the level of intra- and inter-examiner agreement in MIH diagnosis and 25 clinical photographs for pulp involvement assessment. After 2 weeks interval, the photographs were re-analyzed. The agreement was analyzed using the kappa coefficient test. Considering MIH diagnosis at the tooth level (no/yes), the intra-examiner agreement achieved kappa 0.95 for the examiner 1 and 1.0 for the examiner 2. Considering MIH severity at the tooth level (no/mild/severe), the weighted kappa was 0.97 for the examiner 1 and 0.97 for the examiner 2. The inter-examiner agreement was 0.95 and 1.0 for diagnosis and 0.94 and 0.97 for severity assessment, respectively. For pulp involvement, the intra-examiner agreement was 1.0 for both examiners, and inter-examiners was 0.92 and 1.0, for examiners 1 and 2, respectively). The assessment of pulp involvement was dichotomized in yes/no. Statistical Analysis Data were organized in a excel sheet (Microsoft Excel for Mac version 18.80) and then analyzed in SPSS (IMB SPSS Statistics version 29.0.1.0). Exploratory analysis included calculation of proportions of categorical variables and medians, means, and standard deviation of numerical variables. The severity of MIH, considered as an dependent variable, was firstly categorized in 5 levels (W-OP, Y-OP, PEB, AR/AC, and EXT). Then, for some of the associations, it was categorized in 2 levels (W-OP/Y-OP or PEB/AR/AC/EXT) defining the threshold based on enamel disintegration. For the association between MIH severity and treatment demands, children were classified according to the presence of the most complex condition in at least one tooth., according to the following hierarchical sequence: EXT > AR/AC with pulp involvement > AR/AC involving cusp with no pulp involvement > AR/AC involving up to 2 tooth surfaces without cusp or pulp involved > PEB > Y-OP > W-OP. Dependent variables were tested for normality using the Kolmogorov-Smirnov test where p-values < 0.05 indicated non-normal distribution. Therefore, non-parametric tests were used to test the association between dependent and independent variables. Kruskal-Wallis or Mann-Whitney tests were used for numerical variables and Chi-square was used for categorical variables. Results From the 2,352 children enrolled in the 1st to the 7th grades at schools, 2,308 (98,1%) returned the informed consent. Eighty-eight children were absent on the day the examinations, 76 were excluded because did not present any FPM, and 11 children were excluded due neurological condition or orthodontic appliance. The final sample comprised 2,136 children, 6- to 12-year-old, 1,040 (48.7%) girls and 1,096 (51.3%) boys. The prevalence of MIH was 15.5%, affecting 331 children, who were 170 (51.4%) girls and 161 (48.6%) boys with a mean age of 9.0 (SD = 1.80) years. From the 331 children with MIH, 105 (31.7%) presented only W-OP, 53 (16.0%) presented at least one tooth with Y-OP, 38 (11.5%) presented at least one tooth with PEB, 126 (38.1%) presented at least one tooth with AR or AC, and 9 (2.7%) had at least one missing FPM due to MIH. A significant increase in severity was seen in the older children (p = 0.03). These data are displayed in Table 3 . As the severity of MIH increased, the average number of affected FPM and PI also tended to increase (p < 0.05) (Table 4 ). Table 3 : Distribution of the sample according to MIH severity and its association with age. MIH severity All children with MIH Age (years) 6 - 9 10 - 12 p-value* n % n % n % W-OP 105 31.7 64 33.9 41 28.9 0.03 Y-OP 53 16.0 33 17.5 20 14.1 PEB 38 11.5 26 13.3 12 8.5 AR/AC 126 38.1 65 34.4 61 43.0 EXT 9 2.7 1 0.5 8 5.6 Total 331 100 189 100 142 100 * Chi-square test Table 4 Mean number of first permanent molars (FPM) and permanent incisors (PI) affected per child according to the MIH severity (n = 331). MIH severity Affected teeth FPM PI Mean SD Median Mean SD Median W-OP 1.7 a 0.93 2.0 0.57 a 1.06 0 Y-OP 1.89 a 0.80 2.0 0.66 a.c 0.90 0 PEB 2.26 a,b 0.98 2.0 1.32 b 1.17 1 AR/AC 2.72 b,c 0.95 3.0 1.01 b.c 1.29 1 EXT 3.44 c 0.88 4.0 0.56 a,b 0.73 0 Total 2.26 1.03 2.0 0.84 1.16 0 Note: Different superscript letters indicate statistical significance (Kruskal-Wallis test adjusted by Bonferroni correction; p < 0.05). Regarding the distribution within the dentition, 162 (48.9%) children presented only FPM affected, 132 (39.9%) presented both PI and FPM affected, 20 (6.0%) had other permanent teeth (OPT) affected combined with PI and FPM, and 17 (5.1%) had only OPT and FPM affected. The more severe the MIH, the greater the variety of affected teeth. Both PI and OPT were significantly more affected in the more severe forms of MIH (Table 5 ). Table 5 Proportion of children presenting only first permanent molars (FPM) affected, both permanent incisors (PI) and FPM affected, or any other permanent teeth (OPT) affected with or without PI also affected according to the severity of molar incisor hypomineralization (MIH). MIH severity FMP FPM + PI FPM + OPT w/ or wo/ PI Total p-value* n % n % n % n Mild (W-OP/Y-OP) 95 60.1 50 31.6 13 8.2 158 < 0.001 Severe (PEB/AR/AC/ EXT 67 38.7 82 47.4 24 13.9 173 Total 162 48.9 132 39.9 37 11.2 331 *Chi-square test Table 6 shows the prevalence of enamel hypomineralization at the tooth level among the 331 children with MIH. The upper FPM were the most affected teeth followed by the lower FPM, and upper central PI. In terms of proportions, the second permanent molars were more frequently affected than the lateral PI. Figure 1 illustrates the distribution of enamel defect within the dentition based on severity. The FPM showed the highest frequency with the more severe scores (PEB/AR/AC/EXT), being the only teeth missing due to MIH. Y-OP, PEB, AR, and AC were more commonly found among the second permanent molars than in the PI. Table 6 Prevalence of enamel hypomineralization at the tooth level among the 331 children with MIH. Superscript numbers indicate the sequence from the most to the least affected group of teeth. Upper right side Upper left side % n/N Tooth Tooth n/N % 13.2 5/38 3 17 27 3 3/41 7.3 60.4 197/326 1 16 26 1 185/318 58.2 7.3 7/96 6 15 25 6 4/97 4.1 3.7 5/136 6 14 24 6 0/137 0 3.3 3/90 5 13 23 5 5/85 5.9 6.0 15/252 4 12 22 4 16/255 6.3 21.9 65/297 2 11 21 2 67/299 22.4 Lower right side Lower left side % n/N Tooth Tooth n/N % 9.5 31/325 2 41 31 2 39/325 12.0 7.8 23/293 4 42 32 4 21/293 7.2 4.5 6/134 5 43 33 5 4/134 3.0 3.3 4/122 6 44 34 6 5/131 3.8 3.1 3/98 6 45 35 6 6/99 6.1 55.5 183/330 1 46 36 1 183/328 55.8 17.1 7/41 3 47 37 3 9/47 19.1 1 First Permanent Molars; 2 Central Permanent Incisors; 3 Second Permanent Molars; 4 Lateral Permanent Incisors; 5 Permanent Canines; 6 Premolars. Table 7 illustrates the distribution of children based on MIH severity and its correlation with the complexity of the treatment demand for posterior teeth at the individual level. Children exhibiting the mild form of MIH, characterized by W-OP (105; 31.7%) and Y-OP (53; 16.0%), were categorized as those requiring basic treatment. Basic to intermediate treatment was considered recommended for children with PEB (38; 11.5%) or AR/AC involving up to 2 tooth surfaces with no cusps or pulp involvement (19; 5.7%). The more severe forms of MIH, AR/AC involving cusps (76; 23.0%), AR/AC with pulp involvement (31; 9.4%) and EXT (9; 2.7%) were considered as those requiring complex treatments. Regarding the anterior teeth, 158 (47.7%) children has at least one anterior tooth affected, mostly with W-OP (118; 36.1%). Y-OP affected at least one anterior tooth in 30 (9.2%) children, PEB was seen in 5 (1.5%) children and 1 (0.3%) had an anterior tooth with a AR. The complexity of the treatment demand was significantly associated with age as it can be seen in Fig. 2 . Table 7 Complexity of the treatments demands for posterior and anterior teeth according to MIH severity at the individual level. Treatment demands MIH severity n % Posterior teeth Basic Monitoring W-OP 105 31.7 Monitoring or Topical fluoride or Remineralizing agents or Sealants Y-OP 53 16.0 Basic/Intermediate Monitoring or Topical fluoride or Remineralizing agents or Sealants or Direct restoration PEB 38 11.5 Intermediate Direct restoration AR/AC − 2 surfaces 19 5.7 Complex Indirect restoration AR/AC - cusp 76 23.0 Endodontic treatment and Indirect restoration AR/AC - pulp 31 9.4 Extraction and orthodontic monitoring/treatment EXT 9 2.7 Anterior teeth Basic/Intermediate Monitoring W-OP 118 36.1 Aesthetica treatment*: Y-OP 30 9.2 microabrasion resin infiltration or direct restoration Intermediate Direct restoration PEB 5 1.5 AR 1 0.3 * Aesthetic treatment is indicated when aesthetics is a concern for the patient. Discussion The prevalence of MIH observed in the present study, 15.5%, was similar to the estimated prevalence worldwide observed in the most recent meta-analysis which reported an overall prevalence of 13.5% [ 3 ]. The proportion of children with severe MIH, presenting at least one tooth with PEB/AR/AC/EXT, was 52.3%, being higher than the estimated proportion of severe cases reported by the meta-analysis which was 36.3% [ 3 ]. However, some of the studies included in the meta-analysis [ 15 – 20 ] and a more recent study with a quite large sample carried out in Norway [ 21 ], reported similar or even higher proportion of severe cases. In the present study, we speculate whether very mild cases might have been underdiagnosed during the initial screening phase, where children were examined without a dental mirror, using only a head lamp and wood sticks to retract cheeks and tongue. This could explain the difference between our findings and those from a previous study conducted in the same city in 2018, where there was no prior screening stage and all eligible children were comprehensively examined, and the prevalence of MIH was 28.7%, but the severe cases comprised only 24.8% [ 22 ]. Another possible explanation for the higher proportion of severe cases might be the age of the participants. In 2018, only 8-year-old children were included [ 22 ], while in the present study children between 6 and 12 years-old were examined. Previous studies have noted that MIH tend to worsen with age, as the demarcated opacities may progress to PEB over time [ 7 , 23 – 25 ]. The association between age and MIH severity was also found in our study, with the most severe forms of MIH being more prevalent among older children. In line with previous publications [ 17 , 21 , 22 , 26 , 27 ], a higher severity of MIH was associated with a greater number of affected teeth. This trend was observed not only for FPM and PI, but also for other permanent teeth, referred to as HOPT, in agreement with findings from other studies [ 28 , 29 ]. Given the age range of the participants, most of them did not present other permanent teeth besides FPM and PI yet. Despite this, a relatively high number of affected second permanent molars was observed. Proportionally, only FPM and central upper permanent incisors exhibited higher rates of affection than second permanent molars. Furthermore, in terms of severity, second permanent molars were the second group of teeth most severely affected after FPM. High frequency and severity of affection in second permanent molars have been reported in studies involving adolescents and adults [ 28 – 30 ]. Regarding the correlation between MIH severity and treatment requirements, almost half of the children presented only demarcated opacities. At this severity level, children require preventive approach, mostly clinical monitoring, fluorides, and sealants [ 12 ]. Monitoring might be enough for white opacities that are at lower risk of breakdown, while extra protective care might be necessary for yellow opacities that are at higher risk of breakdown [ 7 ]. However, when dealing with anterior teeth, patient’s expectations and self-perception about teeth appearance are mandatory in terms of indication for aesthetic treatment. In general, severe MIH comprises all cases with PEB or atypical caries/restoration regardless its extension. However, treatment decision may differ depending on the size, location, and number of tooth surfaces affected by the defect [ 12 ]. It has been shown that children with MIH present higher caries indices [ 8 , 9 ]. Additionally, they present not only more carious or filled teeth, but also a higher number of carious or filled tooth surfaces per tooth. Moreover, smooth free surfaces usually not affected by typical caries lesions are often affected by PEB or atypical caries/restorations [ 10 ]. In the present study, we categorized the atypical caries/restorations considering the complexity of the treatment required. Cusp involvement and pulp complication were the two major concerns. It was observed that most of the atypical caries/restorations had widespread extension, involving multiple tooth surfaces and cusps. Among the 126 children with at least one tooth with atypical caries/restorations, cusp involvement was observed in slightly more than 60% of cases, and endodontic treatment was necessary in 24%. Only 15% of the children needed only restorations limited to two tooth surfaces with no cusp involvement. Most of the clinical studies assessing the survival rate of direct restorations in MIH molars do not provide details about their extension and whether the fillings involved cusps [ 31 – 35 ]. Direct restorations would be inappropriate in cases where multiple tooth surfaces and cusps are involved [ 12 ] because it extrapolates the indication for direct restorative materials. The inadequate indication of the restorative materials, rather than the hypomineralized enamel itself, might be one of the main reasons for the higher failure rate of direct restorations compared to indirect restorations in patients with MIH. Over a period of 24 months, cusp involvement was the most significant factor related to failure of composite resin restorations in MIH molars [ 36 ]. In another study, after 12 months, more than one third of the composite restorations involving cusps had failed comparing with less than 15% failure of those without cusp involvement [ 37 ]. Hence, whenever a restorative treatment is being planned for a hypomineralized molar, it is advisable to evaluate if the restoration will extend to cusp areas before deciding about which technique and material should be used. Nevertheless, conventional indirect restorative procedures may be more time-consuming and require more cooperation from the patients. General anesthesia or nitrous oxide sedation have been recommended for the comfort of patients [ 32 , 38 ], but these facilities are not always available on a regular basis, particularly in low-income countries. Moreover, conventional preparation for indirect restoration is more invasive and require substantially more dental tissue removal than conservative selective tissue removal usually practiced for direct fillings. Nonetheless, survival rates over 90% after 3 years have been reported for indirect ceramic, resin, and metal onlays [ 32 , 38 , 39 ]. Attempting to maximize success rate of restorations and minimize discomfort for the patients during the clinical procedure, stainless steel crowns (SSC) have been used with no tooth preparation in severely affected molars [ 36 , 40 , 41 ]. This approach is based on an adaptation of the Hall Technique concept originally recommended for carious primary molars [ 42 ]. Although randomized trials and longer follow up are necessary to support its recommendation, it seems that SSC according to the Hall Technique might be a promising strategy for molars with widespread PEB and/or atypical caries involving cusps. The technique is practical, fast and may be used as an interim restoration or at longer-term with the advantage of being minimally invasive. The frequency of pulp involvement and MIH has not been widely explored, but at least two studies reported that pulp complications were significantly more frequent in children with enamel defects, mainly MIH [ 43 , 44 ]. Atypical caries with pulp complication in FPM were observed in almost 10% of the children in the present study. Additionally, indication for extraction or already a missing FPM due to MIH were observed in the sample, but in slightly less than 3% of the children. These cases represent the most severe clinical conditions related to MIH, requiring even more complex treatment. The scenario depicts a group of children with MIH, all under 12 years-old, where for every 10 children, one has at least one FPM requiring endodontic treatment or extraction. The significant association between age the complexity of the treatment demands reflects the worsening of MIH over time. One strength of the present study is its relatively large sample compared to most previous studies [ 3 ]. However, given the non-probability sampling method used, its external validity is reduced. Another limitation was that the assessment of treatment demands according to MIH severity relied solely on clinical data collected during oral examinations by dentists. Patients-report symptoms, such as hypersensitivity and tooth pain, along with aesthetic perceptions, may influence the need for treatment. Nevertheless, based on the findings of the present study, we conclude that children with MIH may present a wide range of treatment demands. When restorative treatment is necessary, it often involves multiple tooth surfaces and cusps, making the choice of technique and restorative material challenging. More complex treatment needs, such as endodontic treatment and extraction, are not uncommon and tend to increase with age. Therefore, it is urgently necessary that oral health policymakers to pay special attention to children with MIH and support oral healthcare to ensure appropriate treatment, aiming to reduce the burden of the disease. Declarations Author Contribution VMS and TKSF contributed to the conception and design of the study. BMSG, RCJ, PPGR, and GFM collected the clinical data and inserted the data in a database. VMS analyzed the data. All authors made substantial contribution to drafting, writing, and critically revising the manuscript. Acknowledgement We acknowledge Fundação de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ) and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). This study was conducted as part of the Master thesis of the first author (BMSG) at Rio de Janeiro State University. Data Availability The data that support the findings of this study are not openly available due to reasons of sensitivity and are available from the corresponding author upon reasonable request. References Weerheijm KL, Jälevik B, Alaluusua S (2001) Molar–Incisor Hypomineralisation. Caries Res 35(5):390–391 Weerheijm KL, Duggal M, Mejàre I, Papagiannoulis L, Koch G, Martens LC et al (2003) Judgement criteria for molar incisor hypomineralisation (MIH) in epidemiologic studies: a summary of the European meeting on MIH held in Athens, 2003. 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Community Dent Oral Epidemiol [Internet]. ;38(1):77–82. http://doi.wiley.com/10.1111/j.1600-0528.2009.00514.x Amend S, Nossol C, Bausback-Schomakers S, Wleklinski C, Scheibelhut C, Pons-Kühnemann J et al (2021) Prevalence of molar-incisor-hypomineralisation (MIH) among 6–12-year-old children in Central Hesse (Germany). Clin Oral Investig 25(4):2093–2100 Arslanagic-Muratbegovic A, Markovic N, Zukanovic A, Tiro A, Dzemidzic V (2020) Molar Incisor Hypomineralization: Prevalence and severity in six to nine-year-old Sarajevo children. Eur J Paediatr Dent 21(3):243–247 COSTA-SILVA CMD, JEREMIAS F, SOUZA JFD, CORDEIRO RDCL, SANTOS‐PINTO L, ZUANON ACC (2010) Molar incisor hypomineralization: prevalence, severity and clinical consequences in Brazilian children. Int J Paediatr Dent 20(6):426–434 Zawaideh FI, Al-Jundi SH, Al-Jaljoli MH (2011) Molar Incisor Hypomineralisation: prevalence in Jordanian children and clinical characteristics. Eur Arch Paediatr Dent 12(1):31–36 Villanueva-Gutiérrez T, Irigoyen-Camacho ME, Castaño-Seiquier A, Zepeda-Zepeda MA, Sanchez-Pérez L, Frechero NM (2019) Prevalence and Severity of Molar–Incisor Hypomineralization, Maternal Education, and Dental Caries: A Cross-Sectional Study of Mexican Schoolchildren with Low Socioeconomic Status. J Int Soc Prev Community Dent 9(5):513–521 Dantas-Neta NB, Moura L, de de FA D, Cruz PF, Moura MS, Paiva SM, Martins CC et al (2016) Impact of molar-incisor hypomineralization on oral health-related quality of life in schoolchildren. Braz Oral Res [Internet]. ;30(1):e117. http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-83242016000100306&lng=en&tlng=en Afzal SH, Skaare AB, Wigen TI, Brusevold IJ (2024) Molar-incisor hypomineralisation: Severity, caries and hypersensitivity. J Dent. ;104881 Reis PPG, Jorge RC, Americano GCA, Pontes N, de Peres ST, Oliveira AMAM (2021) Prevalence and Severity of Molar Incisor Hypomineralization in Brazilian Children. Pediatr Dent 43(4):270–275 Cabral RN, Nyvad B, Soviero VLVM, Freitas E, Leal SC (2020) Reliability and validity of a new classification of MIH based on severity. Clin Oral Investig 24(2):727–734 Neves AB, Americano GCA, Soares DV, Soviero VM (2019) Breakdown of demarcated opacities related to molar-incisor hypomineralization: a longitudinal study. Clin Oral Investig 23(2):611–615 Fragelli CMB, Jeremias F, de Souza JF, Paschoal MA, Cordeiro R, de CL, Santos-Pinto L (2015) Longitudinal Evaluation of the Structural Integrity of Teeth Affected by Molar Incisor Hypomineralisation. Caries Res 49(4):378–383 Abdalla HE, Abuaffan AH, Kemoli AM (2021) Molar incisor hypomineralization, prevalence, pattern and distribution in Sudanese children. BMC Oral Heal 21(1):9 Kevrekidou A, Kosma I, Arapostathis K, Kotsanos N (2015) Molar Incisor Hypomineralization of Eight- and 14-year-old Children: Prevalence, Severity, and Defect Characteristics. Pediatr Dent 37(5):455–461 Kevrekidou A, Kosma I, Kotsanos I, Arapostathis KN, Kotsanos N (2021) Enamel opacities in all other than Molar Incisor Hypomineralisation index teeth of adolescents. Int J Paediatr Dent 31(2):270–277 de Farias AL, Rojas-Gualdrón DF, Bussaneli DG, Santos‐Pinto L, Mejía JD, Restrepo M (2022) Does molar‐incisor hypomineralization (MIH) affect only permanent first molars and incisors? New observations on permanent second molars. Int J Paediatr Dent 32(1):1–10 Hanan SA, de Farias AL, Santos-Pinto L (2023) Molar Incisor Hypomineralization in adolescents and adults and its association with facial profile and occlusion. Clin Oral Investig 27(3):1243–1253 Sönmez H, Saat S (2017) A Clinical Evaluation of Deproteinization and Different Cavity Designs on Resin Restoration Performance in MIH-Affected Molars: Two-Year Results. J Clin Pediatr Dent 41(5):336–342 Linner T, Khazaei Y, Bücher K, Pfisterer J, Hickel R, Kühnisch J (2020) Comparison of four different treatment strategies in teeth with molar-incisor hypomineralization‐related enamel breakdown–A retrospective cohort study. Int J Paediatr Dent 30(5):597–606 FRAGELLI CMB, SOUZA JF, de JEREMIASF, CORDEIRO, R de CL (2015) SANTOS-PINTO L. Molar incisor hypomineralization (MIH): conservative treatment management to restore affected teeth. Braz Oral Res 29(1):1–7 Durmus B, Sezer B, Tugcu N, Caliskan C, Bekiroglu N, Kargul B (2021) Two-Year Survival of High-Viscosity Glass Ionomer in Children with Molar Incisor Hypomineralization. Méd Princ Pr 30(1):73–79 Gatón-Hernandéz P, Serrano CR, Silva LAB, Castañeda ER, Silva RAB, Pucinelli CM et al (2020) Minimally interventive restorative care of teeth with molar incisor hypomineralization and open apex—A 24‐month longitudinal study. Int J Paediatr Dent 30(1):4–10 Farias AL, Rojas-Gualdrón DF, Mejía JD, Bussaneli DG, Santos‐Pinto L, Restrepo M (2022) Survival of stainless‐steel crowns and composite resin restorations in molars affected by molar‐incisor hypomineralization (MIH). Int J Paediatr Dent 32(2):240–250 Rolim TZC, da Costa TRF, Wambier LM, Chibinski AC, Wambier DS, Assunção LR da (2021) Adhesive restoration of molars affected by molar incisor hypomineralization: a randomized clinical trial. Clin Oral Investig 25(3):1513–1524 Gaardmand E, Poulsen S, Haubek D (2013) Pilot study of minimally invasive cast adhesive copings for early restoration of hypomineralised first permanent molars with post-eruptive breakdown. Eur Arch Paediatr Dent 14(1):35–39 Dhareula A, Goyal A, Gauba K, Bhatia SK, Kapur A, Bhandari S (2019) A clinical and radiographic investigation comparing the efficacy of cast metal and indirect resin onlays in rehabilitation of permanent first molars affected with severe molar incisor hypomineralisation (MIH): a 36-month randomised controlled clinical trial. Eur Arch Paediatr Dent 20(5):489–500 Grizzo IC, Bisaia A, Leone CCLD, Campli FGRD, Mendonça FL, Rios D (2022) Revisiting the use of stainless steel crowns for treatment of molar-incisor hypomineralization: a case series. Gen Dent 70(5):62–66 Guerra BMS, Reis PPG, Jorge RC, Soviero VM (2021) Adaptação da Hall Technique para o tratamento restaurador de molares permanentes hipomineralizados: uma série de casos. Rev Assoc Paul Cir Dent 75(3):217–222 Innes NPT, Stirrups DR, Evans DJP, Hall N, Leggate M (2006) A novel technique using preformed metal crowns for managing carious primary molars in general practice — A retrospective analysis. Br Dent J [Internet]. ;200(8):451–4. http://www.nature.com/articles/4813466 Gambetta-Tessini K, Mariño R, Ghanim A, Calache H, Manton DJ (2019) The impact of MIH/HSPM on the carious lesion severity of schoolchildren from Talca, Chile. Eur Arch Paediatr Dent 20(5):417–423 Gambetta-Tessini K, Mariño R, Ghanim A, Calache H, Manton D (2018) Carious lesion severity and demarcated hypomineralized lesions of tooth enamel in schoolchildren from Melbourne, Australia. Aust Dent J 63(3):365–373 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 24 Jan, 2025 Read the published version in Clinical Oral Investigations → Version 1 posted Editorial decision: Revision requested 05 Jul, 2024 Reviews received at journal 30 Jun, 2024 Reviews received at journal 19 Jun, 2024 Reviewers agreed at journal 07 Jun, 2024 Reviewers agreed at journal 02 Jun, 2024 Reviewers invited by journal 31 May, 2024 Submission checks completed at journal 07 May, 2024 Editor assigned by journal 07 May, 2024 First submitted to journal 16 Apr, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4279100","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":301559205,"identity":"ef502fa8-289e-4087-a51e-fbb68356ab68","order_by":0,"name":"Bianca Mattos Santos Guerra","email":"","orcid":"","institution":"Rio de Janeiro State University","correspondingAuthor":false,"prefix":"","firstName":"Bianca","middleName":"Mattos Santos","lastName":"Guerra","suffix":""},{"id":301559206,"identity":"190d9ea4-c748-4038-b1ab-1000396eb785","order_by":1,"name":"Roberta Costa Jorge","email":"","orcid":"","institution":"Arthur Sá Earp Neto University","correspondingAuthor":false,"prefix":"","firstName":"Roberta","middleName":"Costa","lastName":"Jorge","suffix":""},{"id":301559208,"identity":"c6bc1d02-efc3-4a4d-8330-da5391cb5aeb","order_by":2,"name":"Patrícia Papoula Gorni dos Reis","email":"","orcid":"","institution":"Arthur Sá Earp Neto University","correspondingAuthor":false,"prefix":"","firstName":"Patrícia","middleName":"Papoula Gorni dos","lastName":"Reis","suffix":""},{"id":301559210,"identity":"239b0dc3-3636-47d9-93ef-337dc6fd31a6","order_by":3,"name":"Gabriella de Freitas Machado","email":"","orcid":"","institution":"Arthur Sá Earp Neto University","correspondingAuthor":false,"prefix":"","firstName":"Gabriella","middleName":"de Freitas","lastName":"Machado","suffix":""},{"id":301559212,"identity":"a1f16787-0b7c-4073-8be6-2a87297540fd","order_by":4,"name":"Tatiana Kelly da Silva Fidalgo","email":"","orcid":"","institution":"Rio de Janeiro State University","correspondingAuthor":false,"prefix":"","firstName":"Tatiana","middleName":"Kelly da Silva","lastName":"Fidalgo","suffix":""},{"id":301559214,"identity":"78975858-42cc-4b82-8bb2-09e92f64877d","order_by":5,"name":"Vera Mendes Soviero","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3UlEQVRIie2PsQrCMBCGGwLncto1JfoOhUIXi32YQiY3F8XBQXBSZzffIrsU2iUPoHSxCu4dhHYzdXNp7SaYD+644f+4O8syGH4Y1EWu9TDoolC3HqDLJmDv3hZz011elPN4aPM4WTynkyFYNL+dmxSVehxVjM5eiGwkI30YeN60QXEOwuJkI9BV6GeOpFpB4I3K8UGrSiuhVmaOXLUrNgNg/U2ALqJPChl/oaCAMaoAmYKIE5ki0JZfoJfQSzlnob2lp6KSy9DurfN7k/IBxXf/Nl5Dyi5pg8Fg+Btepm46SiSC2O8AAAAASUVORK5CYII=","orcid":"","institution":"Rio de Janeiro State University","correspondingAuthor":true,"prefix":"","firstName":"Vera","middleName":"Mendes","lastName":"Soviero","suffix":""}],"badges":[],"createdAt":"2024-04-17 03:44:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4279100/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4279100/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00784-024-06042-1","type":"published","date":"2025-01-24T15:56:54+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":56564502,"identity":"cac7f085-2205-4f19-b375-614be2fa77bd","added_by":"auto","created_at":"2024-05-15 22:49:00","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":444723,"visible":true,"origin":"","legend":"\u003cp\u003eDistribution of MIH enamel defects within the dentition based on severity. W-OP: white-creamy opacity; Y-OP: yellow-brownish opacity; PEB: post-eruptive breakdown; AR/AC: atypical restoration/atypical caries; EXT: extracted due to MIH.\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4279100/v1/fd775550353708630e099747.jpg"},{"id":56563823,"identity":"864a8644-d2c0-49b9-a551-758e7711fe4c","added_by":"auto","created_at":"2024-05-15 22:41:00","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":115932,"visible":true,"origin":"","legend":"\u003cp\u003eBox plot showing the correlation between age and the complexity of the treatment demand among 331 children with MIH. Kruskal-Wallis test. Basic X Basic/Intermediate: p \u0026gt; 0.05; Basic X Complex; p = 0.06; Basic/Intermediate X Complex: p = 0.04).\u003c/p\u003e","description":"","filename":"Figure2Rplot.png","url":"https://assets-eu.researchsquare.com/files/rs-4279100/v1/ac2d038b1d9d24f21d6624d3.png"},{"id":74858272,"identity":"bd913655-7c3f-4b30-847a-6f5835cd0e2d","added_by":"auto","created_at":"2025-01-27 16:05:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1493813,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4279100/v1/3ecd6159-ff9e-4f57-9afe-803d697c7215.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Prevalence of molar incisor hypomineralization and demands for treatment according to the severity of its clinical manifestation.","fulltext":[{"header":"Introduction","content":"\u003cp\u003eMolar incisor hypomineralization (MIH) has been extensively studied since its first description in 2001[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Characterized as a qualitative defect of enamel mineralization, MIH presents clinically as demarcated opacities ranging in color from white-creamy to yellow-brownish affecting at least one first permanent molar often affecting also permanent incisors [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe estimate overall prevalence of MIH is 13.5%, showing no significant geographical difference between continents, with 36.3% of cases classified as moderate to severe[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The asymmetric characteristic of MIH was confirmed by variations in the number of affected FPM and permanent incisors[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe defective enamel has a lower mineral content, is highly porous, and prone to breakdown as soon as it emerges in the oral cavity and is exposed to functional forces[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. The severity of the hypomineralization correlates with the clinical features of the enamel. Yellow-brownish opacities have a higher protein content and decreased mechanical properties than the white-creamy ones[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Therefore, darker opacities are at higher risk of breakdown and progression to the more severe levels of the condition[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. MIH has been associated with higher caries prevalence and increased caries index in children[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The less mineralized enamel and areas where the enamel disintegrates favor caries progression, resulting in atypical caries lesions affecting multiple tooth surfaces. Moreover, tooth surfaces usually not affected by caries, such as free smooth surfaces and cusps, are often carious or filled in the presence of MIH[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Hence, besides the higher caries index, children with MIH might also require more complex restorative treatment.\u003c/p\u003e \u003cp\u003eMIH has been shown to significantly increase the global burden of dental treatment needs. In 2015/2016, it was estimated that the proportion of patients in need of care (those with tooth pain, hypersensitivity, or post-eruptive breakdown) was 27.4% or 5\u0026nbsp;million new treatment cases each year. Much of the burden of MIH relies on low- and middle-income countries, where the access to dental treatment is limited [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Providing oral care for all the affected individuals is highly challenging. Therefore, aside from assessing the prevalence of MIH, it is necessary to provide data about the demands and complexity of the treatment needs, so that oral health policymakers are substantiated to appropriately plan the oral health care strategies.\u003c/p\u003e \u003cp\u003eThe aim of the present study was to assess the prevalence and severity of MIH in a group of children 6- to 12-year-old and correlate the MIH severity with the complexity of treatment demands.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy design, setting, and participants\u003c/h2\u003e \u003cp\u003eThis was a cross-sectional observational study conducted in the city of Petr\u0026oacute;polis, Brazil. Ten public schools were visited to screen patients for a randomized controlled trial (RCT) that will evaluate the clinical performance of restorative treatment for severe MIH molars (registered in REBEC RBR-4mtq8d9). These ten public schools were chosen because the dentists participating in the RCT as operators are affiliated with the local public oral care system, and the schools are situated within the coverage of this system. Hence, the children selected for the RCT can easily be referred to the nearest oral health unit. Petr\u0026oacute;polis is situated in the southeast region of Brazil, in the state of Rio de Janeiro, has a population of slightly over 300,000 inhabitants. The Human Development Index is 0.745 and the population has access to artificially fluoridated water according to Brazilian regulations.\u003c/p\u003e \u003cp\u003eAll children from the 1st to the 7th grades at school were considered eligible and were invited to participate in the study. The study was approved by the Research Ethics Committee of the Pedro Ernesto University Hospital \u0026ndash; Rio de Janeiro State University (5.763.553). Participation was voluntary and an informed consent was sent to children\u0026rsquo;s caregivers. The inclusion criterion was the presence of at least one FPM erupted. Children presenting other developmental enamel defect than MIH (\u003cem\u003ee.g.\u003c/em\u003e, amelogenesis imperfecta, severe fluorosis), chronic health conditions, unable to cooperate with the dental examination, or with orthodontic appliances were excluded. Children who were absent on the day the school was visited were considered as dropouts.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eMIH detection and severity at the tooth level\u003c/h2\u003e \u003cp\u003eBetween March 2023 and October 2023, two trained and calibrated examiners performed the clinical examinations. First, a screening was conducted in the classrooms with the children seated at their desks and the dentist positioned in front each child. Using a head lamp and wood sticks to gently retract cheeks and tongue, the dentist searched for any signs of suspicious opacities, enamel breakdown, or restorations indicative of MIH according to EAPD criteria[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Children who presented any indicative sign of MIH were referred for a detailed examination in a separate room. Supervised toothbrushing was done prior to the detailed examination. Then, children were seated on regular chairs with a small pillow supporting their heads against the chair back. The dentist was positioned behind the child for a better view of the whole mouth. In addition to the head lamp, the dentist used dental mirror, probe, and cotton rolls if it was necessary to control moisture. The comprehensive mouth examination followed Ghanim[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] criteria for MIH, differentiating between white-creamy and yellow-brownish opacities (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Other enamel defects besides MIH, \u003cem\u003ei.e.\u003c/em\u003e fluorosis and hypoplasia, were also registered but will not be considered in the present study. MIH was registered at the tooth surface level. Trained assistants registered the collected data in datasheets.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMIH severity classification at the tooth level.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eScore\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDescription\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"1\" nameend=\"c3\" namest=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo visible enamel defects.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c3\" namest=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWhite-creamy opacity (W-OP)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c3\" namest=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eYellow-brownish opacity (Y-OP)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c3\" namest=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePost-eruptive breakdown (PEB)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c3\" namest=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAtypical restoration (AR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c3\" namest=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAtypical caries (AC)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c3\" namest=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eExtracted due to MIH (EXT)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c3\" namest=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003e*Teeth extensive coronary disintegration, clearly indicated for extraction were also considered as EXT.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eMIH severity at the individual level\u003c/h2\u003e \u003cp\u003ePatients were categorized based on the severity of MIH, determined by the most severe score assigned to at least one tooth. In this classification, scores for AR and AC were combined as AR/AC to indicate both past and present restorative needs. AR/AC was further divided into three categories from the mildest to the most severe conditions: AR/AC involving up to 2 tooth surfaces without cusp or pulp involvement (AR/AC-2surfaces), AR/AC involving cusp and/or 3 or more tooth surfaces with no pulp involvement (AR/AC-cusp), and AR/AC with pulp involvement (AR/AC-pulp). Pulp involvement was assessed according to PUFA criteria[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. These severity categories of MIH were then correlated with treatment demands, considering the clinical findings (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The recommendations regarding treatment were based on EAPD guidelines [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMIH severity and corresponding treatment recommendation.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eMIH\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003eTreatment\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDescription\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSeverity\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eModalities\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eComplexity\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eW-OP*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMild\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMonitoring\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBasic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eY-OP*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMild/Moderate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMonitoring or\u003c/p\u003e \u003cp\u003eTopical fluoride or remineralizing agents or Sealants\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBasic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePEB (restricted to enamel or exposing hard dentine)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eModerate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMonitoring or\u003c/p\u003e \u003cp\u003eTopical fluoride or remineralizing agents or Sealants or\u003c/p\u003e \u003cp\u003eDirect restoration\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBasic/Intermediate\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAR/AC (extending up to two tooth surfaces, not involving cups, with no pulp involvement).\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSevere\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDirect restoration\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eIntermediate\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAR/AC cusp (extending to three or more tooth surfaces, involving cusps).\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eVery severe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eIndirect restoration\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eComplex\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAR/AC pulp (with pulp involvement).\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eVery severe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eEndodontic treatment and indirect restoration\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eComplex\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEXT (extensive coronary disintegration, with pulp involvement, indicated for extraction or extracted due to MIH).\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eVery severe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eExtraction and/or orthodontic monitoring/orthodontic treatment\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eComplex\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003e* W-OP or Y-OP in anterior teeth might be indicative for aesthetic treatment if aesthetics is a concern for the patient. For any of the severity levels, report of hypersensitivity by the patient may increase the level of the treatment demand.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eTraining and calibration\u003c/h2\u003e \u003cp\u003eThe examiners received theoretical and practical training on how to diagnose MIH and to assess pulp involvement by an experienced examiner. The distinction between MIH and other developmental defects of enamel was emphasized during the training process. Calibration exercises were done with a set of 40 clinical photographs to assess the level of intra- and inter-examiner agreement in MIH diagnosis and 25 clinical photographs for pulp involvement assessment. After 2 weeks interval, the photographs were re-analyzed. The agreement was analyzed using the kappa coefficient test. Considering MIH diagnosis at the tooth level (no/yes), the intra-examiner agreement achieved kappa 0.95 for the examiner 1 and 1.0 for the examiner 2. Considering MIH severity at the tooth level (no/mild/severe), the weighted kappa was 0.97 for the examiner 1 and 0.97 for the examiner 2. The inter-examiner agreement was 0.95 and 1.0 for diagnosis and 0.94 and 0.97 for severity assessment, respectively. For pulp involvement, the intra-examiner agreement was 1.0 for both examiners, and inter-examiners was 0.92 and 1.0, for examiners 1 and 2, respectively). The assessment of pulp involvement was dichotomized in yes/no.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eData were organized in a excel sheet (Microsoft Excel for Mac version 18.80) and then analyzed in SPSS (IMB SPSS Statistics version 29.0.1.0). Exploratory analysis included calculation of proportions of categorical variables and medians, means, and standard deviation of numerical variables. The severity of MIH, considered as an dependent variable, was firstly categorized in 5 levels (W-OP, Y-OP, PEB, AR/AC, and EXT). Then, for some of the associations, it was categorized in 2 levels (W-OP/Y-OP or PEB/AR/AC/EXT) defining the threshold based on enamel disintegration. For the association between MIH severity and treatment demands, children were classified according to the presence of the most complex condition in at least one tooth., according to the following hierarchical sequence: EXT\u0026thinsp;\u0026gt;\u0026thinsp;AR/AC with pulp involvement\u0026thinsp;\u0026gt;\u0026thinsp;AR/AC involving cusp with no pulp involvement\u0026thinsp;\u0026gt;\u0026thinsp;AR/AC involving up to 2 tooth surfaces without cusp or pulp involved\u0026thinsp;\u0026gt;\u0026thinsp;PEB\u0026thinsp;\u0026gt;\u0026thinsp;Y-OP\u0026thinsp;\u0026gt;\u0026thinsp;W-OP. Dependent variables were tested for normality using the Kolmogorov-Smirnov test where p-values\u0026thinsp;\u0026lt;\u0026thinsp;0.05 indicated non-normal distribution. Therefore, non-parametric tests were used to test the association between dependent and independent variables. Kruskal-Wallis or Mann-Whitney tests were used for numerical variables and Chi-square was used for categorical variables.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eFrom the 2,352 children enrolled in the 1st to the 7th grades at schools, 2,308 (98,1%) returned the informed consent. Eighty-eight children were absent on the day the examinations, 76 were excluded because did not present any FPM, and 11 children were excluded due neurological condition or orthodontic appliance. The final sample comprised 2,136 children, 6- to 12-year-old, 1,040 (48.7%) girls and 1,096 (51.3%) boys.\u003c/p\u003e\n\u003cp\u003eThe prevalence of MIH was 15.5%, affecting 331 children, who were 170 (51.4%) girls and 161 (48.6%) boys with a mean age of 9.0 (SD\u0026thinsp;=\u0026thinsp;1.80) years. From the 331 children with MIH, 105 (31.7%) presented only W-OP, 53 (16.0%) presented at least one tooth with Y-OP, 38 (11.5%) presented at least one tooth with PEB, 126 (38.1%) presented at least one tooth with AR or AC, and 9 (2.7%) had at least one missing FPM due to MIH. A significant increase in severity was seen in the older children (p\u0026thinsp;=\u0026thinsp;0.03). These data are displayed in Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e. As the severity of MIH increased, the average number of affected FPM and PI also tended to increase (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Table \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"center\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"8\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 3\u003c/strong\u003e: Distribution of the sample according to MIH severity and its association with age.\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"19.929453262786595%\" rowspan=\"3\"\u003e\n \u003cp\u003eMIH severity\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.044091710758376%\" colspan=\"2\" rowspan=\"2\"\u003e\n \u003cp\u003eAll children\u0026nbsp;\u003c/p\u003e\n \u003cp\u003ewith MIH\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"55.026455026455025%\" colspan=\"5\" valign=\"top\"\u003e\n \u003cp\u003eAge (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"19.35483870967742%\" valign=\"top\"\u003e\n \u003cp\u003e6 - 9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.35483870967742%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.35483870967742%\"\u003e\n \u003cp\u003e10 - 12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.35483870967742%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.580645161290324%\" rowspan=\"2\"\u003e\n \u003cp\u003ep-value*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"16.230366492146597%\" valign=\"top\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.94240837696335%\" valign=\"top\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.706806282722512%\" valign=\"top\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.706806282722512%\" valign=\"top\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.706806282722512%\" valign=\"top\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.706806282722512%\" valign=\"top\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eW-OP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.973451327433628%\" valign=\"top\"\u003e\n \u003cp\u003e105\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.15929203539823%\" valign=\"top\"\u003e\n \u003cp\u003e31.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.619469026548673%\" valign=\"top\"\u003e\n \u003cp\u003e64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.619469026548673%\" valign=\"top\"\u003e\n \u003cp\u003e33.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.619469026548673%\" valign=\"top\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.619469026548673%\" valign=\"top\"\u003e\n \u003cp\u003e28.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.389380530973451%\" rowspan=\"5\"\u003e\n \u003cp\u003e0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"22.828282828282827%\" valign=\"top\"\u003e\n \u003cp\u003eY-OP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.525252525252526%\" valign=\"top\"\u003e\n \u003cp\u003e53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.161616161616163%\" valign=\"top\"\u003e\n \u003cp\u003e16.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e17.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e14.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"22.828282828282827%\" valign=\"top\"\u003e\n \u003cp\u003ePEB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.525252525252526%\" valign=\"top\"\u003e\n \u003cp\u003e38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.161616161616163%\" valign=\"top\"\u003e\n \u003cp\u003e11.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e13.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e8.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"22.828282828282827%\" valign=\"top\"\u003e\n \u003cp\u003eAR/AC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.525252525252526%\" valign=\"top\"\u003e\n \u003cp\u003e126\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.161616161616163%\" valign=\"top\"\u003e\n \u003cp\u003e38.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e34.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e43.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"22.828282828282827%\" valign=\"top\"\u003e\n \u003cp\u003eEXT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.525252525252526%\" valign=\"top\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.161616161616163%\" valign=\"top\"\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.121212121212121%\" valign=\"top\"\u003e\n \u003cp\u003e5.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.973451327433628%\" valign=\"top\"\u003e\n \u003cp\u003e331\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.15929203539823%\" valign=\"top\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.619469026548673%\" valign=\"top\"\u003e\n \u003cp\u003e189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.619469026548673%\" valign=\"top\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.619469026548673%\" valign=\"top\"\u003e\n \u003cp\u003e142\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.619469026548673%\" valign=\"top\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.389380530973451%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"8\" valign=\"top\"\u003e\n \u003cp\u003e* Chi-square test\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003e\u003c/p\u003e\u0026nbsp;\u003ctable id=\"Tab4\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMean number of first permanent molars (FPM) and permanent incisors (PI) affected per child according to the MIH severity (n\u0026thinsp;=\u0026thinsp;331).\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"7\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eMIH severity\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"6\"\u003e\n \u003cp\u003eAffected teeth\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eFPM\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003ePI\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMedian\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMedian\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eW-OP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.7\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.57\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY-OP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.89\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.66\u003csup\u003ea.c\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePEB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.26\u003csup\u003ea,b\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.32\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAR/AC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.72\u003csup\u003eb,c\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.01\u003csup\u003eb.c\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEXT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.44\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.56\u003csup\u003ea,b\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"7\"\u003e\n \u003cp\u003eNote: Different superscript letters indicate statistical significance (Kruskal-Wallis test adjusted by Bonferroni correction; p\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eRegarding the distribution within the dentition, 162 (48.9%) children presented only FPM affected, 132 (39.9%) presented both PI and FPM affected, 20 (6.0%) had other permanent teeth (OPT) affected combined with PI and FPM, and 17 (5.1%) had only OPT and FPM affected. The more severe the MIH, the greater the variety of affected teeth. Both PI and OPT were significantly more affected in the more severe forms of MIH (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab5\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eProportion of children presenting only first permanent molars (FPM) affected, both permanent incisors (PI) and FPM affected, or any other permanent teeth (OPT) affected with or without PI also affected according to the severity of molar incisor hypomineralization (MIH).\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"9\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eMIH severity\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eFMP\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eFPM\u0026thinsp;+\u0026thinsp;PI\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eFPM\u0026thinsp;+\u0026thinsp;OPT w/ or wo/ PI\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003ep-value*\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMild\u003c/p\u003e\n \u003cp\u003e(W-OP/Y-OP)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e60.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e31.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e158\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSevere\u003c/p\u003e\n \u003cp\u003e(PEB/AR/AC/ EXT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e38.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e47.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e173\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e162\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e48.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e132\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e39.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e331\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"9\"\u003e\n \u003cp\u003e*Chi-square test\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eTable \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e shows the prevalence of enamel hypomineralization at the tooth level among the 331 children with MIH. The upper FPM were the most affected teeth followed by the lower FPM, and upper central PI. In terms of proportions, the second permanent molars were more frequently affected than the lateral PI. Figure\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e illustrates the distribution of enamel defect within the dentition based on severity. The FPM showed the highest frequency with the more severe scores (PEB/AR/AC/EXT), being the only teeth missing due to MIH. Y-OP, PEB, AR, and AC were more commonly found among the second permanent molars than in the PI.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab6\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePrevalence of enamel hypomineralization at the tooth level among the 331 children with MIH. Superscript numbers indicate the sequence from the most to the least affected group of teeth.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eUpper right side\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eUpper left side\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en/N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTooth\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTooth\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en/N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5/38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e3\u003c/sup\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3/41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e60.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e197/326\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e1\u003c/sup\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e185/318\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e58.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7/96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e6\u003c/sup\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25\u003csup\u003e6\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4/97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5/136\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e6\u003c/sup\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24\u003csup\u003e6\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0/137\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3/90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e5\u003c/sup\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e23\u003csup\u003e5\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5/85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15/252\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e4\u003c/sup\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22\u003csup\u003e4\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16/255\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e65/297\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e2\u003c/sup\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e67/299\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eLower right side\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eLower left side\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en/N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTooth\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTooth\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en/N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e31/325\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e2\u003c/sup\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e31\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e39/325\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e23/293\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e4\u003c/sup\u003e42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32\u003csup\u003e4\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21/293\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6/134\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e5\u003c/sup\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e33\u003csup\u003e5\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4/134\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4/122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e6\u003c/sup\u003e44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e34\u003csup\u003e6\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5/131\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3/98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e6\u003c/sup\u003e45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e35\u003csup\u003e6\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6/99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e55.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e183/330\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e1\u003c/sup\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e36\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e183/328\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e55.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7/41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003csup\u003e3\u003c/sup\u003e47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e37\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9/47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"6\"\u003e\n \u003cp\u003e\u003csup\u003e1\u003c/sup\u003e First Permanent Molars; \u003csup\u003e2\u003c/sup\u003e Central Permanent Incisors; \u003csup\u003e3\u003c/sup\u003e Second Permanent Molars;\u003c/p\u003e\n \u003cp\u003e\u003csup\u003e4\u003c/sup\u003e Lateral Permanent Incisors; \u003csup\u003e5\u003c/sup\u003e Permanent Canines; \u003csup\u003e6\u003c/sup\u003e Premolars.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eTable \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e illustrates the distribution of children based on MIH severity and its correlation with the complexity of the treatment demand for posterior teeth at the individual level. Children exhibiting the mild form of MIH, characterized by W-OP (105; 31.7%) and Y-OP (53; 16.0%), were categorized as those requiring basic treatment. Basic to intermediate treatment was considered recommended for children with PEB (38; 11.5%) or AR/AC involving up to 2 tooth surfaces with no cusps or pulp involvement (19; 5.7%). The more severe forms of MIH, AR/AC involving cusps (76; 23.0%), AR/AC with pulp involvement (31; 9.4%) and EXT (9; 2.7%) were considered as those requiring complex treatments. Regarding the anterior teeth, 158 (47.7%) children has at least one anterior tooth affected, mostly with W-OP (118; 36.1%). Y-OP affected at least one anterior tooth in 30 (9.2%) children, PEB was seen in 5 (1.5%) children and 1 (0.3%) had an anterior tooth with a AR. The complexity of the treatment demand was significantly associated with age as it can be seen in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab7\" border=\"1\" style=\"margin-right: calc(25%); width: 75%;\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComplexity of the treatments demands for posterior and anterior teeth according to MIH severity at the individual level.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"2\" style=\"width: 50.9407%;\"\u003e\n \u003cp\u003eTreatment demands\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eMIH severity\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" style=\"width: 18.5239%;\"\u003e\n \u003cp\u003ePosterior teeth\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 32.4168%;\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 19.8263%;\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 4.0521%;\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 4.631%;\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\n \u003cp\u003eBasic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eMonitoring\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eW-OP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e105\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e31.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eMonitoring or\u003c/p\u003e\n \u003cp\u003eTopical fluoride or\u003c/p\u003e\n \u003cp\u003eRemineralizing agents or\u003c/p\u003e\n \u003cp\u003eSealants\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eY-OP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e16.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\n \u003cp\u003eBasic/Intermediate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eMonitoring or\u003c/p\u003e\n \u003cp\u003eTopical fluoride or\u003c/p\u003e\n \u003cp\u003eRemineralizing agents or\u003c/p\u003e\n \u003cp\u003eSealants or\u003c/p\u003e\n \u003cp\u003eDirect restoration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003ePEB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e11.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\n \u003cp\u003eIntermediate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eDirect restoration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eAR/AC \u0026minus;\u0026thinsp;2 surfaces\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e5.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\n \u003cp\u003eComplex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eIndirect restoration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eAR/AC - cusp\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e23.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eEndodontic treatment and\u003c/p\u003e\n \u003cp\u003eIndirect restoration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eAR/AC - pulp\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e9.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eExtraction and\u003c/p\u003e\n \u003cp\u003eorthodontic monitoring/treatment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eEXT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAnterior teeth\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\n \u003cp\u003eBasic/Intermediate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eMonitoring\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eW-OP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e118\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e36.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eAesthetica treatment*:\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eY-OP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e9.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003emicroabrasion resin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003einfiltration or direct\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003erestoration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\n \u003cp\u003eIntermediate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\n \u003cp\u003eDirect restoration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003ePEB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 18.5239%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 32.4168%;\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 19.8263%;\"\u003e\n \u003cp\u003eAR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.0521%;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 4.631%;\"\u003e\n \u003cp\u003e0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"5\" style=\"width: 79.4501%;\"\u003e\n \u003cp\u003e* Aesthetic treatment is indicated when aesthetics is a concern for the patient.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe prevalence of MIH observed in the present study, 15.5%, was similar to the estimated prevalence worldwide observed in the most recent meta-analysis which reported an overall prevalence of 13.5% [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The proportion of children with severe MIH, presenting at least one tooth with PEB/AR/AC/EXT, was 52.3%, being higher than the estimated proportion of severe cases reported by the meta-analysis which was 36.3% [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. However, some of the studies included in the meta-analysis [\u003cspan additionalcitationids=\"CR16 CR17 CR18 CR19\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] and a more recent study with a quite large sample carried out in Norway [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], reported similar or even higher proportion of severe cases. In the present study, we speculate whether very mild cases might have been underdiagnosed during the initial screening phase, where children were examined without a dental mirror, using only a head lamp and wood sticks to retract cheeks and tongue. This could explain the difference between our findings and those from a previous study conducted in the same city in 2018, where there was no prior screening stage and all eligible children were comprehensively examined, and the prevalence of MIH was 28.7%, but the severe cases comprised only 24.8% [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Another possible explanation for the higher proportion of severe cases might be the age of the participants. In 2018, only 8-year-old children were included [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], while in the present study children between 6 and 12 years-old were examined. Previous studies have noted that MIH tend to worsen with age, as the demarcated opacities may progress to PEB over time [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan additionalcitationids=\"CR24\" citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. The association between age and MIH severity was also found in our study, with the most severe forms of MIH being more prevalent among older children.\u003c/p\u003e \u003cp\u003eIn line with previous publications [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], a higher severity of MIH was associated with a greater number of affected teeth. This trend was observed not only for FPM and PI, but also for other permanent teeth, referred to as HOPT, in agreement with findings from other studies [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Given the age range of the participants, most of them did not present other permanent teeth besides FPM and PI yet. Despite this, a relatively high number of affected second permanent molars was observed. Proportionally, only FPM and central upper permanent incisors exhibited higher rates of affection than second permanent molars. Furthermore, in terms of severity, second permanent molars were the second group of teeth most severely affected after FPM. High frequency and severity of affection in second permanent molars have been reported in studies involving adolescents and adults [\u003cspan additionalcitationids=\"CR29\" citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eRegarding the correlation between MIH severity and treatment requirements, almost half of the children presented only demarcated opacities. At this severity level, children require preventive approach, mostly clinical monitoring, fluorides, and sealants [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Monitoring might be enough for white opacities that are at lower risk of breakdown, while extra protective care might be necessary for yellow opacities that are at higher risk of breakdown [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, when dealing with anterior teeth, patient\u0026rsquo;s expectations and self-perception about teeth appearance are mandatory in terms of indication for aesthetic treatment.\u003c/p\u003e \u003cp\u003eIn general, severe MIH comprises all cases with PEB or atypical caries/restoration regardless its extension. However, treatment decision may differ depending on the size, location, and number of tooth surfaces affected by the defect [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. It has been shown that children with MIH present higher caries indices [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Additionally, they present not only more carious or filled teeth, but also a higher number of carious or filled tooth surfaces per tooth. Moreover, smooth free surfaces usually not affected by typical caries lesions are often affected by PEB or atypical caries/restorations [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. In the present study, we categorized the atypical caries/restorations considering the complexity of the treatment required. Cusp involvement and pulp complication were the two major concerns. It was observed that most of the atypical caries/restorations had widespread extension, involving multiple tooth surfaces and cusps. Among the 126 children with at least one tooth with atypical caries/restorations, cusp involvement was observed in slightly more than 60% of cases, and endodontic treatment was necessary in 24%. Only 15% of the children needed only restorations limited to two tooth surfaces with no cusp involvement.\u003c/p\u003e \u003cp\u003eMost of the clinical studies assessing the survival rate of direct restorations in MIH molars do not provide details about their extension and whether the fillings involved cusps [\u003cspan additionalcitationids=\"CR32 CR33 CR34\" citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. Direct restorations would be inappropriate in cases where multiple tooth surfaces and cusps are involved [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] because it extrapolates the indication for direct restorative materials. The inadequate indication of the restorative materials, rather than the hypomineralized enamel itself, might be one of the main reasons for the higher failure rate of direct restorations compared to indirect restorations in patients with MIH. Over a period of 24 months, cusp involvement was the most significant factor related to failure of composite resin restorations in MIH molars [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. In another study, after 12 months, more than one third of the composite restorations involving cusps had failed comparing with less than 15% failure of those without cusp involvement [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHence, whenever a restorative treatment is being planned for a hypomineralized molar, it is advisable to evaluate if the restoration will extend to cusp areas before deciding about which technique and material should be used. Nevertheless, conventional indirect restorative procedures may be more time-consuming and require more cooperation from the patients. General anesthesia or nitrous oxide sedation have been recommended for the comfort of patients [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e], but these facilities are not always available on a regular basis, particularly in low-income countries. Moreover, conventional preparation for indirect restoration is more invasive and require substantially more dental tissue removal than conservative selective tissue removal usually practiced for direct fillings. Nonetheless, survival rates over 90% after 3 years have been reported for indirect ceramic, resin, and metal onlays [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAttempting to maximize success rate of restorations and minimize discomfort for the patients during the clinical procedure, stainless steel crowns (SSC) have been used with no tooth preparation in severely affected molars [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e, \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]. This approach is based on an adaptation of the Hall Technique concept originally recommended for carious primary molars [\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e]. Although randomized trials and longer follow up are necessary to support its recommendation, it seems that SSC according to the Hall Technique might be a promising strategy for molars with widespread PEB and/or atypical caries involving cusps. The technique is practical, fast and may be used as an interim restoration or at longer-term with the advantage of being minimally invasive.\u003c/p\u003e \u003cp\u003eThe frequency of pulp involvement and MIH has not been widely explored, but at least two studies reported that pulp complications were significantly more frequent in children with enamel defects, mainly MIH [\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e, \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e]. Atypical caries with pulp complication in FPM were observed in almost 10% of the children in the present study. Additionally, indication for extraction or already a missing FPM due to MIH were observed in the sample, but in slightly less than 3% of the children. These cases represent the most severe clinical conditions related to MIH, requiring even more complex treatment. The scenario depicts a group of children with MIH, all under 12 years-old, where for every 10 children, one has at least one FPM requiring endodontic treatment or extraction. The significant association between age the complexity of the treatment demands reflects the worsening of MIH over time.\u003c/p\u003e \u003cp\u003eOne strength of the present study is its relatively large sample compared to most previous studies [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. However, given the non-probability sampling method used, its external validity is reduced. Another limitation was that the assessment of treatment demands according to MIH severity relied solely on clinical data collected during oral examinations by dentists. Patients-report symptoms, such as hypersensitivity and tooth pain, along with aesthetic perceptions, may influence the need for treatment.\u003c/p\u003e \u003cp\u003eNevertheless, based on the findings of the present study, we conclude that children with MIH may present a wide range of treatment demands. When restorative treatment is necessary, it often involves multiple tooth surfaces and cusps, making the choice of technique and restorative material challenging. More complex treatment needs, such as endodontic treatment and extraction, are not uncommon and tend to increase with age. Therefore, it is urgently necessary that oral health policymakers to pay special attention to children with MIH and support oral healthcare to ensure appropriate treatment, aiming to reduce the burden of the disease.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eVMS and TKSF contributed to the conception and design of the study. BMSG, RCJ, PPGR, and GFM collected the clinical data and inserted the data in a database. VMS analyzed the data. All authors made substantial contribution to drafting, writing, and critically revising the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eWe acknowledge Funda\u0026ccedil;\u0026atilde;o de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ) and Coordena\u0026ccedil;\u0026atilde;o de Aperfei\u0026ccedil;oamento de Pessoal de N\u0026iacute;vel Superior (CAPES). This study was conducted as part of the Master thesis of the first author (BMSG) at Rio de Janeiro State University.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe data that support the findings of this study are not openly available due to reasons of sensitivity and are available from the corresponding author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eWeerheijm KL, J\u0026auml;levik B, Alaluusua S (2001) Molar\u0026ndash;Incisor Hypomineralisation. Caries Res 35(5):390\u0026ndash;391\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWeerheijm KL, Duggal M, Mej\u0026agrave;re I, Papagiannoulis L, Koch G, Martens LC et al (2003) Judgement criteria for molar incisor hypomineralisation (MIH) in epidemiologic studies: a summary of the European meeting on MIH held in Athens, 2003. 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Braz Oral Res [Internet]. ;30(1):e117. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.scielo.br/scielo.php?script=sci_arttext\u0026amp;pid=S1806-83242016000100306\u0026amp;lng=en\u0026amp;tlng=en\u003c/span\u003e\u003cspan address=\"http://www.scielo.br/scielo.php?script=sci_arttext\u0026amp;pid=S1806-83242016000100306\u0026amp;lng=en\u0026amp;tlng=en\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAfzal SH, Skaare AB, Wigen TI, Brusevold IJ (2024) Molar-incisor hypomineralisation: Severity, caries and hypersensitivity. J Dent. ;104881\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eReis PPG, Jorge RC, Americano GCA, Pontes N, de Peres ST, Oliveira AMAM (2021) Prevalence and Severity of Molar Incisor Hypomineralization in Brazilian Children. 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Aust Dent J 63(3):365\u0026ndash;373\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"clinical-oral-investigations","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cloi","sideBox":"Learn more about [Clinical Oral Investigations](http://link.springer.com/journal/784)","snPcode":"784","submissionUrl":"https://submission.nature.com/new-submission/784/3","title":"Clinical Oral Investigations","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Molar incisor hypomineralization, Prevalence, Treatment need","lastPublishedDoi":"10.21203/rs.3.rs-4279100/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4279100/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003eAim\u003c/b\u003e\u003c/p\u003e \u003cp\u003eAssess the prevalence and severity of molar incisor hypomineralization (MIH) in children 6- to 12-year-old and correlate MIH severity with the complexity of treatment demands.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMaterials and methods\u003c/b\u003e\u003c/p\u003e \u003cp\u003eBetween March and October 2023, 2,136 children were screened for MIH by two calibrated examiners. MIH severity was categorized in mild, moderate, severe, and very severe. Treatment requirements were categorized in basic, intermediate, and complex.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e \u003cp\u003eThe prevalence of MIH was 15.5% (n\u0026thinsp;=\u0026thinsp;331). Among the 126 children with atypical caries/restoration, cusp involvement was observed in 60.3%, endodontic treatment was necessary in 24.6%, only 15% needed restorations limited to two tooth surfaces with no cusp involvement. Extraction due to MIH was observed in 2.7%.\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusion\u003c/b\u003e\u003c/p\u003e \u003cp\u003eThe prevalence of MIH was in accordance with previous literature. Whenever a restorative treatment was necessary, it often involved multiple tooth surfaces and cusps. The complexity of treatment demands increased with age. It is necessary that oral health policymakers pay special attention to children with MIH to ensure appropriate treatment.\u003c/p\u003e","manuscriptTitle":"Prevalence of molar incisor hypomineralization and demands for treatment according to the severity of its clinical manifestation.","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-05-15 22:40:55","doi":"10.21203/rs.3.rs-4279100/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-07-05T07:50:22+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-30T10:51:35+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-19T14:15:20+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"273841567045359032108653649875113603632","date":"2024-06-07T14:28:44+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"319553473394659623906932597716426645739","date":"2024-06-02T15:35:46+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-05-31T15:27:07+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-05-07T09:21:51+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-05-07T09:21:51+00:00","index":"","fulltext":""},{"type":"submitted","content":"Clinical Oral Investigations","date":"2024-04-17T03:29:53+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"clinical-oral-investigations","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cloi","sideBox":"Learn more about [Clinical Oral Investigations](http://link.springer.com/journal/784)","snPcode":"784","submissionUrl":"https://submission.nature.com/new-submission/784/3","title":"Clinical Oral Investigations","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"f57b9eb3-f61d-49a7-9238-68c2a76c12b7","owner":[],"postedDate":"May 15th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-01-27T15:58:52+00:00","versionOfRecord":{"articleIdentity":"rs-4279100","link":"https://doi.org/10.1007/s00784-024-06042-1","journal":{"identity":"clinical-oral-investigations","isVorOnly":false,"title":"Clinical Oral Investigations"},"publishedOn":"2025-01-24 15:56:54","publishedOnDateReadable":"January 24th, 2025"},"versionCreatedAt":"2024-05-15 22:40:55","video":"","vorDoi":"10.1007/s00784-024-06042-1","vorDoiUrl":"https://doi.org/10.1007/s00784-024-06042-1","workflowStages":[]},"version":"v1","identity":"rs-4279100","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4279100","identity":"rs-4279100","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}