Distribution of oral microbial flora among the students of a tertiary institution in Nigeria: A descriptive cross-sectional study

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Daramola, Josephine A. Oke, Faith G. Ademulegun, Olabisi A. Oduwole This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8711724/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract Background: The human oral cavity harbours a diverse microbial community that influences both oral and systemic health. Disruption of this microbial balance can result in dental conditions such as tooth decay. University students are particularly at risk due to poor dietary habits and inconsistent oral hygiene. This study investigated the distribution of oral microbial flora and their association with tooth decay among students of a private tertiary institution in Nigeria. Methods: Oral swab samples were collected and cultured using standard microbiological techniques, including growth on chocolate, blood, and MacConkey agars for bacterial isolation, and Sabouraud agar for fungal isolation, and biochemical tests were performed for identification. A structured questionnaire assessed oral hygiene practices, sweet consumption, and oral health status. Data were analyzed using descriptive statistics, Chi-square tests, and binary logistic regression to identify variables. Results: The predominant microbial isolates were Streptococcus mutans (25%), Staphylococcus aureus (17%), Streptococcus sanguinis (12%), and Candida albicans (10%). Tooth decay was reported by 52% of participants and was significantly associated with S. mutans (p < 0.001), S. aureus (p = 0.006), C. albicans (p = 0.001), and S. sanguinis (p = 0.031). These microorganisms also increased the odds of tooth decay, with odds ratios (OR) of 3.27(95% CI = 1.77–6.05), 2.08(95% CI = 1.23–3.52), 1.95(95% CI = 1.06–3.58), and 2.51(95% CI = 1.40–4.50) respectively (p < 0.05). Furthermore, sweet consumption showed a significant positive correlation with tooth decay (p < 0.001). Conclusion: Streptococcus mutans , S. aureus, S. sanguinis , and Candida albicans were strongly associated with tooth decay and high sugar intake was a key risk factor. Tooth decay Oral hygiene Dental Caries Tooth decay Oral microbiota Oral flora Figures Figure 1 Background The human oral cavity harbours a diverse and complex microbial community, collectively known as the oral microbiome, which plays a crucial role in maintaining oral and systemic health [ 1 ]. This microbiome comprises bacteria, fungi, archaea, viruses, and protozoa that coexist in a delicate balance [ 2 ]. Disruption of this equilibrium due to poor oral hygiene, unhealthy diet, systemic disease, or antibiotic use can promote the growth of pathogenic species, leading to oral and systemic infections [ 3 , 4 ]. Bacteria and fungi are the predominant members of the oral microbiome. Commensal bacteria such as Streptococcus , Actinomyces , and Veillonella contribute to oral homeostasis by preventing the overgrowth of pathogens and supporting digestive processes [ 5 ]. However, pathogenic bacteria including Porphyromonas gingivalis , Treponema denticola , and Fusobacterium nucleatum have been associated with periodontal disease and systemic conditions such as cardiovascular disease and diabetes mellitus [ 6 ]. Likewise, fungi such as Candida albicans , though typically commensal, can become opportunistic pathogens under conditions such as immunosuppression or antibiotic use, leading to oral candidiasis [ 7 ]. Behavioral factors, such as diet, oral hygiene, and lifestyle have been reported to influence the composition of oral microbial [ 8 ]. Poor oral hygiene fosters plaque accumulation, while high sugar (sweet or candy) consumption promotes acidogenic bacteria like Streptococcus mutans , a major contributor to tooth decay [ 9 ]. In contrast, diets rich in fibre and polyphenols support a more balanced microbiota [ 10 ]. Globally, oral microbial infections, particularly tooth decay and periodontal disease, remain among the most prevalent chronic conditions [ 11 ] with higher incidence in low-income populations due to limited access to oral care [ 12 ]. Although bacterial pathogens have been extensively studied, the contribution of fungal flora such as Candida albicans to oral health remains inadequately explored. This gap is especially evident among student populations in Nigerian tertiary institutions, where lifestyle and dietary habits may influence microbial composition. This study therefore aimed to investigate the distribution of oral microbial flora and their association with tooth decay among students of Achievers University, Owo, Nigeria. METHODS Study design & setting This was a cross-sectional study designed to determine the distribution of oral microbial flora (bacteria and fungi) among students of a private University, in Southern Nigeria. The university comprises students from diverse geographical and socio-economic backgrounds, making it suitable for investigating variations in oral microbial composition. Study Population and Ethical consideration The study population comprised undergraduate students from a private university in Southern Nigeria. Eligible participants were registered students who had not taken any antibiotics or antifungal medications within the 14 days preceding sample collection. Only individuals who provided written informed consent were enrolled in the study. Participants with chronic medical conditions known to affect immune function, such as HIV/AIDS, diabetes mellitus, or cancer, were excluded. Ethical approval for the study was obtained from the Health Research Ethical Committee (HREC) of the Federal Medical Center, Owo, Ondo State (Approval No: FMC OWO/HREC/2025/30). Sample Size Determination The sample size was calculated using the formula for health studies proposed by [ 13 ], based on a 27% prevalence of oral diseases (tooth decay) among slum residents in Nigeria. With a 95% confidence level (Z = 1.96) and a 5% margin of error (d = 0.05), the required sample size was 302. To accommodate a potential 5% non-response rate, the adjusted sample size was increased to 318, which constituted the total number targeted for the study. Sample Collection and Processing A random sampling technique was used to recruit consenting participants for oral sample collection. The study was conducted over a six-month period, from February to July 2025. Oral swab samples were collected using sterile cotton swabs moistened with sterile physiological saline to enhance microbial adherence. Swabs were gently rubbed over the tongue surface, buccal mucosa, and gingival crevices to obtain representative microbial samples from different oral sites. Each swab was immediately placed in its sterile casing and promptly transported to the Medical Microbiology Laboratory, of the University. Laboratory Investigations and Analysis Bacterial Isolation Each sample was first inoculated into Peptone Water and incubated at 37°C for 30 minutes to enrich bacterial growth. Subsequently, a loopful of the enriched culture was streaked onto MacConkey, chocolate, and blood agar plates using the streak plate method. The plates were incubated at 37°C for 24–48 hours. After incubation, colonies were observed for morphological characteristics such as size, color, shape, and hemolytic reactions on blood agar. Distinct colonies were further subjected to Gram staining and biochemical tests for identification. Fungal Isolation Swab samples were directly streaked onto Sabouraud dextrose agar (SDA) and incubated at room temperature (25–30°C) for 3–7 days to allow fungal growth. Following incubation, colonies were examined for macroscopic features such as color, texture, growth rate, and morphology. Microscopic examination was performed using Lactophenol cotton blue (LPCB) staining to observe hyphal structure, conidia, and spores for species identification. Germ Tube Test A 10% serum solution was prepared by diluting serum in a 1:10 ratio with normal saline or distilled water. A fresh yeast colony was emulsified in the serum and incubated at 37°C for 3 hours. A drop of the culture was placed on a slide and examined under ×40 objective lens. The presence of tube-like outgrowths without constriction at the base indicated Candida albicans , while their absence suggested non- albicans species. Gram staining and Biochemical Characterization of Bacterial Isolates Biochemical characterization of bacterial isolates was performed using standard tests, including catalase, coagulase, indole, urease, oxidase, and sugar fermentation tests. These assays aided in determining cell wall type, enzyme activity, and metabolic properties. Gram staining was done to differentiate Gram-positive and Gram-negative bacteria, while catalase and oxidase tests assessed enzymatic reactions. Indole, urease, and sugar fermentation tests evaluated metabolic capabilities, and the coagulase test identified Staphylococcus aureus among Gram-positive cocci. Statistical Analysis Data were analyzed using SPSS software (version 25.0). Results were expressed in proportions and frequencies. The association between categorical variables was determined using the Chi-square test, while binary logistic regression was employed to identify significant predictors of tooth decay. Statistical significance was set at p ≤ 0.05. RESULTS A total of 302 students participated in this study. 53% were females and the majority of respondents (50%) were between 21–25 years old (Table 1 ). Table 1 Demographic Characteristics of Respondents Variable Category Frequency (n) Percentage (%) Gender Male 142 47.0% Female 160 53.0% Age Group 16–20 82 27% 21–25 150 50% 26–30 58 19% 31 and above 12 4% All participants reported engaging in tooth brushing, with approximately half (51%) brushing both in the morning and at night. Of the respondents, 41% reported having had a previous professional dental cleaning, and sweet consumption was common, and reported by 58% of participants (Supplementary table 1 ). Approximately two-thirds (66%) of the participants reported experiencing at least one oral health issue. Among these, tooth decay was the most frequently reported condition (79%), followed by gum bleeding (50%) and halitosis (47%). Fewer respondents reported cases of oral thrush (15%) and mouth ulcers (12%). Additionally, 26% (78/302) of the students had undergone a tooth extraction, with 21% (16/78) having had the procedure more than twice (Supplementary Table 2). A total of 434 microbial isolates were obtained from the oral cavities of the 302 participants. Bacterial isolates constituted the majority (82%), while fungal isolates accounted for 18%. Among bacterial isolates, Streptococcus mutans and Streptococcus sanguinis were the most prevalent, collectively representing 37% of the isolates. This was followed by Staphylococcus aureus (17%) and Staphylococcus spp (7%). Other species that were less frequently isolated were Klebsiella spp., Proteus spp., and Escherichia coli. The only fungal isolates identified were Candida species (20%) (Table 2 ). Table 2 Distribution and Frequency of Bacterial and Fungal Species Identified from Oral Samples Commonly Identified Microbial Species Classification Number of Isolates Percentage (%) Streptococcus mutans Bacteria 108 25% Staphylococcus aureus Staphylococcus spp Bacteria Bacteria 72 29 17% 7% Streptococcus sanguinis Bacteria 51 12% Streptococcus spp. Bacteria 38 9% Klebsiella spp. Bacteria 23 5% Proteus spp. Bacteria 19 4% Escherichia coli Bacteria 15 4% Candida albicans Fungi 43 10% Candida spp. (non-albicans) Fungi 36 8% Total 434 100% There was a clear upward trend in the occurrence of tooth decay as the frequency of sweet intake increased. Individuals who reported ‘never consumed’ sweets had the lowest prevalence of tooth decay (16%), compared to while 70% of those who consumed sweets daily (Fig. 1 ). Streptococcus mutans was the most prevalent microorganism among participants with tooth decay, and was statistically significantly associated with the condition at 78% (84/108 (p < 0.001). This was followed by Candida albicans (74%, p = 0.001) Streptococcus sanguinis (70%, p = 0.031) and Staphylococcus aureus (67%, p = 0.006) (Table 3 ). Table 3 Association Between Microbial Isolates and Presence of Tooth Decay Among Respondents Microorganism Tooth Decay Present (n = 157) Tooth Decay Absent (n = 145) Total Chi-Square (χ²) Df p-value Streptococcus mutans 84 (78%) 24 (22%) 108 (100%) 26.34 1 < 0.001 No Streptococcus mutans 73 (38%) 121 (62%) 194 (100%) Staphylococcus aureus 48(67%) 24(33%) 72(100%) 7.54 1 0.006 No Staphylococcus aureus 109(47%) 121(53%) 230(100%) Candida albicans 32(74%) 11(26%) 43(100%) 10.89 1 0.001 No Candida albicans 125(48%) 134(52%) 259(100%) Staphylococcus spp 16(67%) 8(33%) 24(100%) 4.6 1 0.003 No Staphylococcus spp 141(51%) 137(49%) 278(100%) Streptococcus sanguinis 39(70%) 17(30%) 56(100%) 4.68 1 0.031 No Streptococcus sanguinis 118(48%) 128(52%) 246(100%) Klebsiella spp. 10(67%) 5(33%) 15(100%) 1.12 1 0.29 No Klebsiella spp 147(51%) 140(49%) 287(100%) Escherichia coli 10(67%) 5(33%) 15(100%) 0.79 1 0.37 No Escherichia coli 147(51%) 140(49%) 287(100%) Proteus spp. 4(67%) 2(33%) 6(100%) 0.96 1 0.33 No Proteus spp 153(52%) (143(48%) 296(100%) Candida spp. (non-A.) 25(69%) 11(31%) 36(100%) 6.84 1 0.009 No Candida spp. (non-A.) 132(50%) 134(50%) 266(100%) A logistic regression analysis of factors associated with tooth decay among showed that colonization with Streptococcus mutans was significantly associated with increased odds of tooth decay, with affected individuals being more than three times as likely to develop tooth decay (OR = 3.27; 95% CI = 1.77–6.05, p < 0.001). Colonization with Candida albicans increased the likelihood of decay by approximately 2.5-fold ( p = 0.002), (Suppl. table 3). Furthermore, the use of fluoride-containing toothpaste was associated with reduced odds of tooth decay (OR = 0.60, p = 0.033), indicating a protective effect. Gender and brushing frequency were not statistically significant predictors in the model (supplementary table 3). In contrast, species such as Klebsiella spp., Proteus spp., and E. coli showed no significant associations. DISCUSSION Oral microbial infections, encompassing both bacterial and fungal pathogens, represent a significant global health concern. Eight bacterial isolates and two fungal isolates were identified in this study, including Streptococcus mutans , Streptococcus sanguinis , Streptococcus spp. , Staphylococcus aureus , Staphylococcus spp. , Proteus spp. , Escherichia coli , Candida albicans , and Candida spp. Some of these bacterial and fungal species were similarly isolated from oral swab samples in the research conducted by [ 14 ], where three isolates, Streptococcus mutans , Staphylococcus aureus , and Candida albicans were identified. The results of this study indicate that Streptococcus mutans was the most prevalent isolate, identified in 25% of participants, and was significantly associated with tooth decay (χ² = 26.34, p < 0.001). Other microorganisms significantly associated with tooth decay included Staphylococcus aureus (prevalence 17%, p = 0.006), Streptococcus sanguinis (prevalence 12%, p = 0.031), and Candida albicans (prevalence 10%, χ² = 10.89, p = 0.001). The association with C. albicans supports the understanding that this fungus, while typically a commensal member of the oral flora, can become pathogenic when the local ecological balance is disrupted [ 15 ].The isolation of S. mutans as the predominant organism aligns with the findings from another study which confirm its role as a primary pathogen in cariogenesis due to its aciduric properties and biofilm-forming ability [ 16 ], In contrast, [ 14 ], reported Staphylococcus aureus as the most prevalent organism in their study The role of S. aureus in tooth decay remains unclear. It is believed that while S. aureus may not be directly involved in caries initiation, it could act as a secondary colonizer or influence biofilm stability through immune modulation [ 17 ]. Our study also isolated Candida albicans in 10% of participants, and its presence was significantly associated with tooth decay (χ² = 10.89, p = 0.001). This finding aligns with other reports suggesting that while Candida can exist as part of the normal oral flora, it may become pathogenic when the ecological balance is disrupted, particularly in high-sugar environments or in combination with Streptococcus mutans [ 18 ]. In addition to the dominant species isolated, low frequencies of Klebsiella spp. , Proteus spp. , and Escherichia coli were also observed. This is consistent with other reports. The believe is that these organisms are not typical oral residents and may represent transient colonization resulting from dietary sources, gastrointestinal reflux, or poor hygiene [ 19 ]. Their lack of significant association with tooth decay in this study supports their classification as incidental rather than pathogenic members of the oral flora. Binary logistic regression analysis revealed that the presence of S. mutans (OR = 3.27, p < 0.001) and C. albicans (OR = 2.51, p = 0.002) significantly predicted tooth decay. These findings are consistent with prior studies by [ 20 ] and [ 21 ], which highlight synergistic biofilm interactions between these organisms, resulting in more acid-tolerant and cariogenic biofilms. This study did not observe an association between gender, distribution of oral microbiota, oral hygiene practice nor was there an association with tooth decay, although [ 22 ]. This may be an indication that behavioral and dietary patterns likely play a more central role than biological sex in shaping oral microbial composition [ 23 ]. Furthermore, this study revealed that although all students reported brushing their teeth, only 51% brushed twice daily, and fewer than 30% used adjunct oral hygiene aids such as dental floss or mouthwash. Logistic regression analysis demonstrated that the use of fluoride toothpaste reduced the odds of tooth decay (OR = 0.60, p = 0.033), reinforcing World Health Organization guidelines [ 24 ] that emphasize fluoride's protective benefits through enamel remineralization. This study also found a statistically significant positive correlation between sweet consumption and tooth decay (ρ = 0.412, p < 0.001). The prevalence of tooth decay increased from 16% among individuals who did not consume sweets to 70% among those who consumed them daily, a trend consistent with findings from a previous report [ 25 ]. Conclusion This study identified Streptococcus mutans , Streptococcus sanguinis , Staphylococcus aureus , and Candida albicans as the most prevalent microorganisms, each demonstrating a significant association with tooth decay. A high frequency of sweet consumption was also identified as a key risk factor. Despite high proportion of self-reported tooth brushing, significant gaps were observed in comprehensive oral care practices, including the underutilization of adjunct hygiene aids and professional dental services. These findings underscore the necessity for targeted oral health education among university students to mitigate the burden of tooth decay and promote a healthier oral microbiome. Declarations Ethics approval and consent to participate The study was approved by the Health Research Ethical Committee (HREC) of Federal Medical Center, Owo, Ondo State (Approval No: FMC OWO/HREC/2025/30). The study was conducted in accordance with the Declaration of Helsinki. The informed consent was obtained from all of the participants. Clinical Trial Number Not applicable Consent for publication Not Applicable. Competing interests The authors declare no competing interests. Funding This study received no external funding Author Contribution OAO conceived the idea, JAO and OAO designed the study, FID collected the data under the supervision of JAO. OAO interpreted the data analysis, FGA wrote the first manuscript, and reviewed by OAO. All authors read and approved the final draft of the manuscript. Acknowledgement We acknowledge Segun Bello and Oluwatobi Olatunji for assisting with the data analysis. Data Availability The datasets use and analyzed during the current study are available from the corresponding author on reasonable request. References Kilian M, Chapple ILC, Hannig M, Marsh PD, Meuric V, Pedersen AML, et al. The microbiome of the oral cavity: A role in health and disease. Genome Med. 2016;8(1):46. Wade WG. The oral microbiome in health and disease. Philos Trans R Soc Lond B Biol Sci. 2021;76(24):372–400. Lamont RJ, Koo H, Hajishengallis G. The oral microbiota: Dynamic communities and host interactions. Nat Rev Microbiol. 2018;16(12):745–59. Jenkinson HF, Lamont RJ. Oral microbial communities in sickness and in health. Trends Microbiol. 2015;13(12):589–95. Takahashi N. Oral microbiome metabolism: From who are they? to what are they doing? J Dent Res. 2015;94(12):1628–37. Hajishengallis G, Lamont RJ. Breaking bad: Manipulation of the host response by Porphyromonas gingivalis. Eur J Immunol. 2016;46(1):40–50. O'Donnell LE, Robertson D, Nile CJ, Cross LJ, Riggio M, Sherriff A, et al. The oral microbiome of denture wearers is influenced by levels of natural dentition. PLoS ONE. 2017;12(9):e0184624. Zaura E, Nicu EA, Krom BP, Keijser BJF. Acquiring and maintaining a normal oral microbiome: Current perspective. Front Cell Infect Microbiol. 2017;7:120. Klein MI, Hwang G, Santos PHS, Campanella OH, Koo H. Streptococcus mutans-derived extracellular matrix in cariogenic oral biofilms. Front Cell Infect Microbiol. 2015;5:10. Jensen H, Grimmer S, Naterstad K, Axelsson L. In vitro testing of commercial and potential probiotic lactic acid bacteria. Int J Food Microbiol. 2016;187:1–6. Petersen PE, Ogawa H. Prevention of tooth decay through the use of fluoride–the WHO approach. Community Dent Health. 2016;33(2):66–8. Peres MA, Macpherson LMD, Weyant RJ, Daly B, Venturelli R, Mathur MR, et al. Oral diseases: A global public health challenge. Lancet. 2019;394(94):249–60. Lwanga SK, Lemeshow S. Sample size determination in health studies: A practical manual. Geneva: World Health Organization; 1991. Mbakwem A, Okeke P, Ibrahim T. Prevalence of Staphylococcus aureus among oral microbiota in a Nigerian cohort. Niger J Clin Microbiol. 2012;18(2):45–51. Diaz PI, Hong BY, Dupuy AK, Strausbaugh LD, Dongari-Bagtzoglou A. Interactions between Candida albicans and oral bacteria in biofilms on mucosal surfaces. FEMS Yeast Res. 2022;22(1):foac042. Nyvad B, Takahashi N. Caries ecology revisited: Microbial dynamics and the caries process. Caries Res. 2020;42(6):409–18. Guggenheim B, Gmür R, Galicia JC, Stathopoulou PG, Benakanakere MR, Kinane DF, et al. Staphylococcus aureus enhances biofilm formation of Porphyromonas gingivalis. J Dent Res. 2020;99(5):557–64. Liu X, Tong X, Jie Z, Zhu J, Tian L, Sun Q, et al. Sex differences in the oral microbiome, host traits, and their causal relationships. iScience. 2022;26(1):105839. Beighton D. The complex oral microflora of high-risk individuals and groups and its role in the caries process. Community Dent Oral Epidemiol. 2020;48(3):213–19. Falsetta ML, Klein MI, Colonne PM, Scott-Anne K, Gregoire S, Pai CH, et al. Symbiotic relationship between Streptococcus mutans and Candida albicans synergizes virulence of plaque biofilms in vivo. Infect Immun. 2014;82(5):1968–81. Metwalli KH, Khan SA, Krom BP, Jabra-Rizk MA. The role of Candida albicans in tooth decay and its interaction with oral bacteria. Pathog Dis. 2023;81(1):54–67. Silva MJ, Siqueira MBD, Rocha MR. Oral health knowledge and self-care behaviors among university students: A cross-sectional study. BMC Oral Health. 2022;22(1):80. Peltzer K, Pengpid S. Oral and hand hygiene behavior and risk factors among in-school adolescents in four Southeast Asian countries. Int J Environ Res Public Health. 2019;16(21):4043. World Health Organization. Nigeria: Oral health country profile 2022. Geneva: World Health Organization. 2022. Accessed on June 20, 2025. Available from: https://www.who.int/publications/i/item/9789240065571 Takahashi N, Nyvad B. The role of bacteria in the caries process: Ecological perspectives. J Dent Res. 2016;95(3):242–8. Additional Declarations No competing interests reported. Supplementary Files SuppleTables.docx Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 28 Feb, 2026 Reviews received at journal 26 Feb, 2026 Reviewers agreed at journal 26 Feb, 2026 Reviews received at journal 24 Feb, 2026 Reviewers agreed at journal 24 Feb, 2026 Reviewers invited by journal 17 Feb, 2026 Editor invited by journal 29 Jan, 2026 Editor assigned by journal 28 Jan, 2026 Submission checks completed at journal 28 Jan, 2026 First submitted to journal 27 Jan, 2026 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-8711724","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":595080250,"identity":"1c3e8574-4bfd-4c84-8ae7-5e60d23eaa4c","order_by":0,"name":"Fayokemi I. 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Oduwole","email":"data:image/png;base64,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","orcid":"","institution":"Achievers University","correspondingAuthor":true,"prefix":"","firstName":"Olabisi","middleName":"A.","lastName":"Oduwole","suffix":""}],"badges":[],"createdAt":"2026-01-27 14:38:25","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8711724/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8711724/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":103217588,"identity":"cc0176ba-78b6-4f0f-b741-3d5d16704d10","added_by":"auto","created_at":"2026-02-23 09:45:07","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":235550,"visible":true,"origin":"","legend":"\u003cp\u003eLine Chart of Sweet Intake vs. Tooth Decay Prevalence\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-8711724/v1/1ac56a57ba717fc6979038b7.jpeg"},{"id":103514569,"identity":"36c34a4a-3fd9-45de-a73d-0662e16cf4f1","added_by":"auto","created_at":"2026-02-26 14:21:28","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1088231,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8711724/v1/c8b7b9ed-44de-4aa1-8942-56fed4913880.pdf"},{"id":103506085,"identity":"8236abcc-f88f-404f-810b-6945d7729686","added_by":"auto","created_at":"2026-02-26 13:34:01","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":22498,"visible":true,"origin":"","legend":"","description":"","filename":"SuppleTables.docx","url":"https://assets-eu.researchsquare.com/files/rs-8711724/v1/55089295212a4f84677d2ae7.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Distribution of oral microbial flora among the students of a tertiary institution in Nigeria: A descriptive cross-sectional study","fulltext":[{"header":"Background","content":"\u003cp\u003eThe human oral cavity harbours a diverse and complex microbial community, collectively known as the oral microbiome, which plays a crucial role in maintaining oral and systemic health [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. This microbiome comprises bacteria, fungi, archaea, viruses, and protozoa that coexist in a delicate balance [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Disruption of this equilibrium due to poor oral hygiene, unhealthy diet, systemic disease, or antibiotic use can promote the growth of pathogenic species, leading to oral and systemic infections [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBacteria and fungi are the predominant members of the oral microbiome. Commensal bacteria such as \u003cem\u003eStreptococcus\u003c/em\u003e, \u003cem\u003eActinomyces\u003c/em\u003e, and \u003cem\u003eVeillonella\u003c/em\u003e contribute to oral homeostasis by preventing the overgrowth of pathogens and supporting digestive processes [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. However, pathogenic bacteria including \u003cem\u003ePorphyromonas gingivalis\u003c/em\u003e, \u003cem\u003eTreponema denticola\u003c/em\u003e, and \u003cem\u003eFusobacterium nucleatum\u003c/em\u003e have been associated with periodontal disease and systemic conditions such as cardiovascular disease and diabetes mellitus [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Likewise, fungi such as \u003cem\u003eCandida albicans\u003c/em\u003e, though typically commensal, can become opportunistic pathogens under conditions such as immunosuppression or antibiotic use, leading to oral candidiasis [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBehavioral factors, such as diet, oral hygiene, and lifestyle have been reported to influence the composition of oral microbial [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Poor oral hygiene fosters plaque accumulation, while high sugar (sweet or candy) consumption promotes acidogenic bacteria like \u003cem\u003eStreptococcus mutans\u003c/em\u003e, a major contributor to tooth decay [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. In contrast, diets rich in fibre and polyphenols support a more balanced microbiota [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Globally, oral microbial infections, particularly tooth decay and periodontal disease, remain among the most prevalent chronic conditions [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e] with higher incidence in low-income populations due to limited access to oral care [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Although bacterial pathogens have been extensively studied, the contribution of fungal flora such as \u003cem\u003eCandida albicans\u003c/em\u003e to oral health remains inadequately explored. This gap is especially evident among student populations in Nigerian tertiary institutions, where lifestyle and dietary habits may influence microbial composition.\u003c/p\u003e \u003cp\u003eThis study therefore aimed to investigate the distribution of oral microbial flora and their association with tooth decay among students of Achievers University, Owo, Nigeria.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy design \u0026amp; setting\u003c/h2\u003e \u003cp\u003eThis was a cross-sectional study designed to determine the distribution of oral microbial flora (bacteria and fungi) among students of a private University, in Southern Nigeria. The university comprises students from diverse geographical and socio-economic backgrounds, making it suitable for investigating variations in oral microbial composition.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eStudy Population and Ethical consideration\u003c/h3\u003e\n\u003cp\u003eThe study population comprised undergraduate students from a private university in Southern Nigeria. Eligible participants were registered students who had not taken any antibiotics or antifungal medications within the 14 days preceding sample collection. Only individuals who provided written informed consent were enrolled in the study. Participants with chronic medical conditions known to affect immune function, such as HIV/AIDS, diabetes mellitus, or cancer, were excluded. Ethical approval for the study was obtained from the Health Research Ethical Committee (HREC) of the Federal Medical Center, Owo, Ondo State (Approval No: FMC OWO/HREC/2025/30).\u003c/p\u003e\n\u003ch3\u003eSample Size Determination\u003c/h3\u003e\n\u003cp\u003eThe sample size was calculated using the formula for health studies proposed by [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], based on a 27% prevalence of oral diseases (tooth decay) among slum residents in Nigeria. With a 95% confidence level (Z\u0026thinsp;=\u0026thinsp;1.96) and a 5% margin of error (d\u0026thinsp;=\u0026thinsp;0.05), the required sample size was 302. To accommodate a potential 5% non-response rate, the adjusted sample size was increased to 318, which constituted the total number targeted for the study.\u003c/p\u003e\n\u003ch3\u003eSample Collection and Processing\u003c/h3\u003e\n\u003cp\u003e A random sampling technique was used to recruit consenting participants for oral sample collection. The study was conducted over a six-month period, from February to July 2025. Oral swab samples were collected using sterile cotton swabs moistened with sterile physiological saline to enhance microbial adherence. Swabs were gently rubbed over the tongue surface, buccal mucosa, and gingival crevices to obtain representative microbial samples from different oral sites. Each swab was immediately placed in its sterile casing and promptly transported to the Medical Microbiology Laboratory, of the University.\u003c/p\u003e\n\u003ch3\u003eLaboratory Investigations and Analysis\u003c/h3\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eBacterial Isolation\u003c/h2\u003e \u003cp\u003eEach sample was first inoculated into Peptone Water and incubated at 37\u0026deg;C for 30 minutes to enrich bacterial growth. Subsequently, a loopful of the enriched culture was streaked onto MacConkey, chocolate, and blood agar plates using the streak plate method. The plates were incubated at 37\u0026deg;C for 24\u0026ndash;48 hours. After incubation, colonies were observed for morphological characteristics such as size, color, shape, and hemolytic reactions on blood agar. Distinct colonies were further subjected to Gram staining and biochemical tests for identification.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eFungal Isolation\u003c/h3\u003e\n\u003cp\u003eSwab samples were directly streaked onto Sabouraud dextrose agar (SDA) and incubated at room temperature (25\u0026ndash;30\u0026deg;C) for 3\u0026ndash;7 days to allow fungal growth. Following incubation, colonies were examined for macroscopic features such as color, texture, growth rate, and morphology. Microscopic examination was performed using Lactophenol cotton blue (LPCB) staining to observe hyphal structure, conidia, and spores for species identification.\u003c/p\u003e\n\u003ch3\u003eGerm Tube Test\u003c/h3\u003e\n\u003cp\u003eA 10% serum solution was prepared by diluting serum in a 1:10 ratio with normal saline or distilled water. A fresh yeast colony was emulsified in the serum and incubated at 37\u0026deg;C for 3 hours. A drop of the culture was placed on a slide and examined under \u0026times;40 objective lens. The presence of tube-like outgrowths without constriction at the base indicated \u003cem\u003eCandida albicans\u003c/em\u003e, while their absence suggested non-\u003cem\u003ealbicans\u003c/em\u003e species.\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eGram staining and Biochemical Characterization of Bacterial Isolates\u003c/h2\u003e \u003cp\u003eBiochemical characterization of bacterial isolates was performed using standard tests, including catalase, coagulase, indole, urease, oxidase, and sugar fermentation tests. These assays aided in determining cell wall type, enzyme activity, and metabolic properties. Gram staining was done to differentiate Gram-positive and Gram-negative bacteria, while catalase and oxidase tests assessed enzymatic reactions. Indole, urease, and sugar fermentation tests evaluated metabolic capabilities, and the coagulase test identified \u003cem\u003eStaphylococcus aureus\u003c/em\u003e among Gram-positive cocci.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eData were analyzed using SPSS software (version 25.0). Results were expressed in proportions and frequencies. The association between categorical variables was determined using the Chi-square test, while binary logistic regression was employed to identify significant predictors of tooth decay. Statistical significance was set at p\u0026thinsp;\u0026le;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eA total of 302 students participated in this study. 53% were females and the majority of respondents (50%) were between 21\u0026ndash;25 years old (Table \u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\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\u003eDemographic Characteristics of Respondents\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=\"char\" char=\".\" 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\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCategory\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFrequency (n)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePercentage (%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e142\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e47.0%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e160\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e53.0%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge Group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16\u0026ndash;20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e27%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21\u0026ndash;25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e150\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e50%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e26\u0026ndash;30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e19%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e31 and above\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e All participants reported engaging in tooth brushing, with approximately half (51%) brushing both in the morning and at night. Of the respondents, 41% reported having had a previous professional dental cleaning, and sweet consumption was common, and reported by 58% of participants (Supplementary table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e Approximately two-thirds (66%) of the participants reported experiencing at least one oral health issue. Among these, tooth decay was the most frequently reported condition (79%), followed by gum bleeding (50%) and halitosis (47%). Fewer respondents reported cases of oral thrush (15%) and mouth ulcers (12%). Additionally, 26% (78/302) of the students had undergone a tooth extraction, with 21% (16/78) having had the procedure more than twice (Supplementary Table\u0026nbsp;2). A total of 434 microbial isolates were obtained from the oral cavities of the 302 participants. Bacterial isolates constituted the majority (82%), while fungal isolates accounted for 18%. Among bacterial isolates, \u003cem\u003eStreptococcus mutans and Streptococcus sanguinis\u003c/em\u003e were the most prevalent, collectively representing 37% of the isolates. This was followed by \u003cem\u003eStaphylococcus aureus\u003c/em\u003e (17%) and \u003cem\u003eStaphylococcus\u003c/em\u003e spp (7%). Other species that were less frequently isolated were \u003cem\u003eKlebsiella\u003c/em\u003e spp., \u003cem\u003eProteus\u003c/em\u003e spp., and \u003cem\u003eEscherichia coli.\u003c/em\u003e The only fungal isolates identified were \u003cem\u003eCandida\u003c/em\u003e species (20%) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\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\u003eDistribution and Frequency of Bacterial and Fungal Species Identified from Oral Samples\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=\"char\" char=\".\" 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\" colname=\"c1\"\u003e \u003cp\u003eCommonly Identified Microbial Species\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eClassification\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNumber\u003c/p\u003e \u003cp\u003eof Isolates\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePercentage (%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eStreptococcus mutans\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBacteria\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e108\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eStaphylococcus aureus\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003eStaphylococcus spp\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBacteria\u003c/p\u003e \u003cp\u003eBacteria\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e72\u003c/p\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17%\u003c/p\u003e \u003cp\u003e7%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eStreptococcus sanguinis\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBacteria\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eStreptococcus spp.\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBacteria\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eKlebsiella spp.\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBacteria\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eProteus spp.\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBacteria\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eEscherichia coli\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBacteria\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eCandida albicans\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFungi\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCandida spp. (non-albicans)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFungi\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e434\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e100%\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThere was a clear upward trend in the occurrence of tooth decay as the frequency of sweet intake increased. Individuals who reported \u0026lsquo;never consumed\u0026rsquo; sweets had the lowest prevalence of tooth decay (16%), compared to while 70% of those who consumed sweets daily (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cem\u003eStreptococcus mutans\u003c/em\u003e was the most prevalent microorganism among participants with tooth decay, and was statistically significantly associated with the condition at 78% (84/108 (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). This was followed by \u003cem\u003eCandida albicans\u003c/em\u003e (74%, p\u0026thinsp;=\u0026thinsp;0.001) \u003cem\u003eStreptococcus sanguinis\u003c/em\u003e (70%, p\u0026thinsp;=\u0026thinsp;0.031) and \u003cem\u003eStaphylococcus aureus\u003c/em\u003e (67%, p\u0026thinsp;=\u0026thinsp;0.006) (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003e\u003cb\u003eAssociation Between Microbial Isolates and Presence of Tooth Decay Among Respondents\u003c/b\u003e\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\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 \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMicroorganism\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTooth Decay Present\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;157)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eTooth Decay Absent\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;145)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eChi-Square (χ\u0026sup2;)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eDf\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eStreptococcus mutans\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e84 (78%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24 (22%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e108 (100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e26.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eNo Streptococcus mutans\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e73 (38%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e121 (62%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e194 (100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eStaphylococcus aureus\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e48(67%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24(33%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e7.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.006\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eNo Staphylococcus aureus\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e109(47%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e121(53%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e230(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eCandida albicans\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32(74%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11(26%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e43(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e10.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eNo Candida albicans\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e125(48%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e134(52%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e259(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eStaphylococcus spp\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16(67%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8(33%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eNo Staphylococcus spp\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e141(51%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e137(49%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e278(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eStreptococcus sanguinis\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39(70%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17(30%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e56(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.031\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eNo Streptococcus sanguinis\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e118(48%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e128(52%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e246(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eKlebsiella spp.\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10(67%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5(33%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.29\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eNo Klebsiella spp\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e147(51%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e140(49%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e287(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eEscherichia coli\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10(67%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5(33%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.37\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eNo Escherichia coli\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e147(51%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e140(49%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e287(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eProteus spp.\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4(67%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(33%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eNo Proteus spp\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e153(52%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e(143(48%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e296(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eCandida spp. (non-A.)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25(69%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11(31%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e36(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e6.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.009\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eNo Candida spp. (non-A.)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e132(50%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e134(50%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e266(100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eA logistic regression analysis of factors associated with tooth decay among showed that colonization with \u003cem\u003eStreptococcus mutans\u003c/em\u003e was significantly associated with increased odds of tooth decay, with affected individuals being more than three times as likely to develop tooth decay (OR\u0026thinsp;=\u0026thinsp;3.27; 95% CI\u0026thinsp;=\u0026thinsp;1.77\u0026ndash;6.05, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Colonization with \u003cem\u003eCandida albicans\u003c/em\u003e increased the likelihood of decay by approximately 2.5-fold (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002), (Suppl. table 3). Furthermore, the use of fluoride-containing toothpaste was associated with reduced odds of tooth decay (OR\u0026thinsp;=\u0026thinsp;0.60, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.033), indicating a protective effect. Gender and brushing frequency were not statistically significant predictors in the model (supplementary table 3). In contrast, species such as \u003cem\u003eKlebsiella spp., Proteus spp., and E. coli\u003c/em\u003e showed no significant associations.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eOral microbial infections, encompassing both bacterial and fungal pathogens, represent a significant global health concern. Eight bacterial isolates and two fungal isolates were identified in this study, including \u003cem\u003eStreptococcus mutans\u003c/em\u003e, \u003cem\u003eStreptococcus sanguinis\u003c/em\u003e, \u003cem\u003eStreptococcus spp.\u003c/em\u003e, \u003cem\u003eStaphylococcus aureus\u003c/em\u003e, \u003cem\u003eStaphylococcus spp.\u003c/em\u003e, \u003cem\u003eProteus spp.\u003c/em\u003e, \u003cem\u003eEscherichia coli\u003c/em\u003e, \u003cem\u003eCandida albicans\u003c/em\u003e, and \u003cem\u003eCandida spp.\u003c/em\u003e Some of these bacterial and fungal species were similarly isolated from oral swab samples in the research conducted by [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], where three isolates, \u003cem\u003eStreptococcus mutans\u003c/em\u003e, \u003cem\u003eStaphylococcus aureus\u003c/em\u003e, and \u003cem\u003eCandida albicans\u003c/em\u003e were identified.\u003c/p\u003e \u003cp\u003eThe results of this study indicate that \u003cem\u003eStreptococcus mutans\u003c/em\u003e was the most prevalent isolate, identified in 25% of participants, and was significantly associated with tooth decay (χ\u0026sup2; = 26.34, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Other microorganisms significantly associated with tooth decay included \u003cem\u003eStaphylococcus aureus\u003c/em\u003e (prevalence 17%, p\u0026thinsp;=\u0026thinsp;0.006), \u003cem\u003eStreptococcus sanguinis\u003c/em\u003e (prevalence 12%, p\u0026thinsp;=\u0026thinsp;0.031), and \u003cem\u003eCandida albicans\u003c/em\u003e (prevalence 10%, χ\u0026sup2; = 10.89, p\u0026thinsp;=\u0026thinsp;0.001). The association with \u003cem\u003eC. albicans\u003c/em\u003e supports the understanding that this fungus, while typically a commensal member of the oral flora, can become pathogenic when the local ecological balance is disrupted [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].The isolation of \u003cem\u003eS. mutans\u003c/em\u003e as the predominant organism aligns with the findings from another study which confirm its role as a primary pathogen in cariogenesis due to its aciduric properties and biofilm-forming ability [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], In contrast, [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], reported \u003cem\u003eStaphylococcus aureus\u003c/em\u003e as the most prevalent organism in their study The role of \u003cem\u003eS. aureus\u003c/em\u003e in tooth decay remains unclear. It is believed that while \u003cem\u003eS. aureus\u003c/em\u003e may not be directly involved in caries initiation, it could act as a secondary colonizer or influence biofilm stability through immune modulation [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur study also isolated \u003cem\u003eCandida albicans\u003c/em\u003e in 10% of participants, and its presence was significantly associated with tooth decay (χ\u0026sup2; = 10.89, p\u0026thinsp;=\u0026thinsp;0.001). This finding aligns with other reports suggesting that while \u003cem\u003eCandida\u003c/em\u003e can exist as part of the normal oral flora, it may become pathogenic when the ecological balance is disrupted, particularly in high-sugar environments or in combination with \u003cem\u003eStreptococcus mutans\u003c/em\u003e [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn addition to the dominant species isolated, low frequencies of \u003cem\u003eKlebsiella spp.\u003c/em\u003e, \u003cem\u003eProteus spp.\u003c/em\u003e, and \u003cem\u003eEscherichia coli\u003c/em\u003e were also observed. This is consistent with other reports. The believe is that these organisms are not typical oral residents and may represent transient colonization resulting from dietary sources, gastrointestinal reflux, or poor hygiene [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Their lack of significant association with tooth decay in this study supports their classification as incidental rather than pathogenic members of the oral flora.\u003c/p\u003e \u003cp\u003eBinary logistic regression analysis revealed that the presence of \u003cem\u003eS. mutans\u003c/em\u003e (OR\u0026thinsp;=\u0026thinsp;3.27, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and \u003cem\u003eC. albicans\u003c/em\u003e (OR\u0026thinsp;=\u0026thinsp;2.51, p\u0026thinsp;=\u0026thinsp;0.002) significantly predicted tooth decay. These findings are consistent with prior studies by [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] and [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], which highlight synergistic biofilm interactions between these organisms, resulting in more acid-tolerant and cariogenic biofilms. This study did not observe an association between gender, distribution of oral microbiota, oral hygiene practice nor was there an association with tooth decay, although [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. This may be an indication that behavioral and dietary patterns likely play a more central role than biological sex in shaping oral microbial composition [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFurthermore, this study revealed that although all students reported brushing their teeth, only 51% brushed twice daily, and fewer than 30% used adjunct oral hygiene aids such as dental floss or mouthwash. Logistic regression analysis demonstrated that the use of fluoride toothpaste reduced the odds of tooth decay (OR\u0026thinsp;=\u0026thinsp;0.60, p\u0026thinsp;=\u0026thinsp;0.033), reinforcing World Health Organization guidelines [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e] that emphasize fluoride's protective benefits through enamel remineralization.\u003c/p\u003e \u003cp\u003eThis study also found a statistically significant positive correlation between sweet consumption and tooth decay (ρ\u0026thinsp;=\u0026thinsp;0.412, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The prevalence of tooth decay increased from 16% among individuals who did not consume sweets to 70% among those who consumed them daily, a trend consistent with findings from a previous report [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e].\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study identified \u003cem\u003eStreptococcus mutans\u003c/em\u003e, \u003cem\u003eStreptococcus sanguinis\u003c/em\u003e, \u003cem\u003eStaphylococcus aureus\u003c/em\u003e, and \u003cem\u003eCandida albicans\u003c/em\u003e as the most prevalent microorganisms, each demonstrating a significant association with tooth decay. A high frequency of sweet consumption was also identified as a key risk factor. Despite high proportion of self-reported tooth brushing, significant gaps were observed in comprehensive oral care practices, including the underutilization of adjunct hygiene aids and professional dental services. These findings underscore the necessity for targeted oral health education among university students to mitigate the burden of tooth decay and promote a healthier oral microbiome.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e \u003cp\u003e The study was approved by the Health Research Ethical Committee (HREC) of Federal Medical Center, Owo, Ondo State (Approval No: FMC OWO/HREC/2025/30). The study was conducted in accordance with the Declaration of Helsinki. The informed consent was obtained from all of the participants.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eClinical Trial Number\u003c/h2\u003e \u003cp\u003eNot applicable\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eConsent for publication\u003c/h2\u003e \u003cp\u003eNot Applicable.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eCompeting interests\u003c/h2\u003e \u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis study received no external funding\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eOAO conceived the idea, JAO and OAO designed the study, FID collected the data under the supervision of JAO. OAO interpreted the data analysis, FGA wrote the first manuscript, and reviewed by OAO. All authors read and approved the final draft of the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eWe acknowledge Segun Bello and Oluwatobi Olatunji for assisting with the data analysis.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe datasets use and analyzed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eKilian M, Chapple ILC, Hannig M, Marsh PD, Meuric V, Pedersen AML, et al. The microbiome of the oral cavity: A role in health and disease. Genome Med. 2016;8(1):46.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWade WG. The oral microbiome in health and disease. Philos Trans R Soc Lond B Biol Sci. 2021;76(24):372\u0026ndash;400.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLamont RJ, Koo H, Hajishengallis G. The oral microbiota: Dynamic communities and host interactions. Nat Rev Microbiol. 2018;16(12):745\u0026ndash;59.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJenkinson HF, Lamont RJ. Oral microbial communities in sickness and in health. Trends Microbiol. 2015;13(12):589\u0026ndash;95.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTakahashi N. Oral microbiome metabolism: From who are they? to what are they doing? J Dent Res. 2015;94(12):1628\u0026ndash;37.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHajishengallis G, Lamont RJ. Breaking bad: Manipulation of the host response by Porphyromonas gingivalis. Eur J Immunol. 2016;46(1):40\u0026ndash;50.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eO'Donnell LE, Robertson D, Nile CJ, Cross LJ, Riggio M, Sherriff A, et al. The oral microbiome of denture wearers is influenced by levels of natural dentition. PLoS ONE. 2017;12(9):e0184624.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZaura E, Nicu EA, Krom BP, Keijser BJF. Acquiring and maintaining a normal oral microbiome: Current perspective. Front Cell Infect Microbiol. 2017;7:120.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKlein MI, Hwang G, Santos PHS, Campanella OH, Koo H. Streptococcus mutans-derived extracellular matrix in cariogenic oral biofilms. Front Cell Infect Microbiol. 2015;5:10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJensen H, Grimmer S, Naterstad K, Axelsson L. In vitro testing of commercial and potential probiotic lactic acid bacteria. Int J Food Microbiol. 2016;187:1\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePetersen PE, Ogawa H. Prevention of tooth decay through the use of fluoride\u0026ndash;the WHO approach. Community Dent Health. 2016;33(2):66\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePeres MA, Macpherson LMD, Weyant RJ, Daly B, Venturelli R, Mathur MR, et al. Oral diseases: A global public health challenge. Lancet. 2019;394(94):249\u0026ndash;60.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLwanga SK, Lemeshow S. Sample size determination in health studies: A practical manual. Geneva: World Health Organization; 1991.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMbakwem A, Okeke P, Ibrahim T. Prevalence of Staphylococcus aureus among oral microbiota in a Nigerian cohort. Niger J Clin Microbiol. 2012;18(2):45\u0026ndash;51.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDiaz PI, Hong BY, Dupuy AK, Strausbaugh LD, Dongari-Bagtzoglou A. Interactions between Candida albicans and oral bacteria in biofilms on mucosal surfaces. 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Oral and hand hygiene behavior and risk factors among in-school adolescents in four Southeast Asian countries. Int J Environ Res Public Health. 2019;16(21):4043.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWorld Health Organization. Nigeria: Oral health country profile 2022. Geneva: World Health Organization. 2022. Accessed on June 20, 2025. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.who.int/publications/i/item/9789240065571\u003c/span\u003e\u003cspan address=\"https://www.who.int/publications/i/item/9789240065571\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTakahashi N, Nyvad B. The role of bacteria in the caries process: Ecological perspectives. J Dent Res. 2016;95(3):242\u0026ndash;8.\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":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Tooth decay, Oral hygiene, Dental Caries, Tooth decay, Oral microbiota, Oral flora","lastPublishedDoi":"10.21203/rs.3.rs-8711724/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8711724/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground:\u003c/h2\u003e \u003cp\u003e The human oral cavity harbours a diverse microbial community that influences both oral and systemic health. Disruption of this microbial balance can result in dental conditions such as tooth decay. University students are particularly at risk due to poor dietary habits and inconsistent oral hygiene. This study investigated the distribution of oral microbial flora and their association with tooth decay among students of a private tertiary institution in Nigeria.\u003c/p\u003e\u003ch2\u003eMethods:\u003c/h2\u003e \u003cp\u003eOral swab samples were collected and cultured using standard microbiological techniques, including growth on chocolate, blood, and MacConkey agars for bacterial isolation, and Sabouraud agar for fungal isolation, and biochemical tests were performed for identification. A structured questionnaire assessed oral hygiene practices, sweet consumption, and oral health status. Data were analyzed using descriptive statistics, Chi-square tests, and binary logistic regression to identify variables.\u003c/p\u003e\u003ch2\u003eResults:\u003c/h2\u003e \u003cp\u003eThe predominant microbial isolates were \u003cem\u003eStreptococcus mutans\u003c/em\u003e (25%), \u003cem\u003eStaphylococcus aureus\u003c/em\u003e (17%), \u003cem\u003eStreptococcus sanguinis\u003c/em\u003e (12%), and \u003cem\u003eCandida albicans\u003c/em\u003e (10%). Tooth decay was reported by 52% of participants and was significantly associated with \u003cem\u003eS. mutans\u003c/em\u003e (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), \u003cem\u003eS. aureus\u003c/em\u003e (p\u0026thinsp;=\u0026thinsp;0.006), \u003cem\u003eC. albicans\u003c/em\u003e (p\u0026thinsp;=\u0026thinsp;0.001), and \u003cem\u003eS. sanguinis\u003c/em\u003e (p\u0026thinsp;=\u0026thinsp;0.031). These microorganisms also increased the odds of tooth decay, with odds ratios (OR) of 3.27(95% CI\u0026thinsp;=\u0026thinsp;1.77\u0026ndash;6.05), 2.08(95% CI\u0026thinsp;=\u0026thinsp;1.23\u0026ndash;3.52), 1.95(95% CI\u0026thinsp;=\u0026thinsp;1.06\u0026ndash;3.58), and 2.51(95% CI\u0026thinsp;=\u0026thinsp;1.40\u0026ndash;4.50) respectively (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Furthermore, sweet consumption showed a significant positive correlation with tooth decay (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\u003ch2\u003eConclusion:\u003c/h2\u003e \u003cp\u003e \u003cem\u003eStreptococcus mutans\u003c/em\u003e, \u003cem\u003eS. aureus, S. sanguinis\u003c/em\u003e, and \u003cem\u003eCandida albicans\u003c/em\u003e were strongly associated with tooth decay and high sugar intake was a key risk factor.\u003c/p\u003e","manuscriptTitle":"Distribution of oral microbial flora among the students of a tertiary institution in Nigeria: A descriptive cross-sectional study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-23 09:45:00","doi":"10.21203/rs.3.rs-8711724/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"68983448731378458088542071472980423058","date":"2026-02-28T17:34:26+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-26T12:06:59+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"297904527716342108931680572537028866716","date":"2026-02-26T10:52:22+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-24T23:07:02+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"279286769119377805731690055368471932076","date":"2026-02-24T22:17:33+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-02-17T07:48:59+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-01-29T12:01:31+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-28T10:25:10+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-28T10:20:50+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Oral Health","date":"2026-01-27T14:17:05+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8b7a36fc-e305-4f96-ad2c-6b94a7a905d6","owner":[],"postedDate":"February 23rd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-02-23T09:45:00+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-23 09:45:00","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8711724","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8711724","identity":"rs-8711724","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}