Does Auto-clave Sterilization Affect Nickle Ion Release of Stainless Steel Crowns and Space Maintainer Bands?

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Noura Alessa, Habah Alhamdan, Shahad Alrobaish, Nisrin AlQahtani, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4857451/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Aim This study aimed to investigate the effect of autoclave sterilization on the leaching of nickel ions from stainless steel crowns and space-maintainer bands used in pediatric dentistry. Materials and Methods Sixty space maintainer bands and 60 stainless steel crowns were divided into sterilized and non-sterilized groups. These samples were immersed in artificial saliva, placed in individual petri dishes, and then incubated at 37°C. The samples were analyzed for 42 d using a gas chromatography-mass spectrometry (GC-MS) machine to quantify the release of nickel ions. Results Nickel release was higher in the sterilized samples than in the non-sterilized samples for both space maintainer bands and stainless steel crowns. This trend persisted throughout most days of the experiment, with a peak release observed on day 7. The sterilized group showed significantly higher levels of ion release than the non-sterilized group ( p < 0.05). Conclusion This study suggests that nickel allergy testing may be advisable before placing stainless steel crowns or space maintainers, particularly for patients at risk of allergies. Dentists should be mindful of the increased nickel release observed from sterilized crowns and bands, as this information could influence treatment decisions, especially in children who are predisposed to allergies. Nickle ion release Auto-clave sterilization of stainless steel Ion leaching of stainless steel crowns space maintainer bands Figures Figure 1 Background Prefabricated stainless steel crowns (SSCs) and space maintainer bands (SM bands) have become essential dental devices in pediatric dentistry owing to the high prevalence of dental caries among children ( 1 , 2 ). SSCs are preformed crowns that are used to restore deciduous molars that have undergone pulpal therapy ( 3 ). These crowns protect primary molars by reducing the risk of post-operative symptoms ( 4 ). Their prefabricated design simplifies use and reduces chair time and cost ( 5 ). In contrast, SM bands are metal bands placed on an abutment tooth as part of a space-maintaining appliance. They prevent space loss and tooth drift and maintain proper alignment ( 6 ). SM bands are indicated following the early loss of a deciduous tooth to preserve space for the eruption of permanent teeth. Its appropriate use can prevent the need for extensive orthodontic treatment ( 6 ). The increasing popularity of SSCs and SM has been attributed to their ease of use and affordability. However, concerns have arisen regarding the nickel (Ni) content of these alloys, which has historically been linked to allergic reactions. This composition prompted inquiries into its biocompatibility, particularly regarding the potential release of Ni ions into the oral cavity after cementation ( 3 , 7 ). However, some studies have focused on determining whether factors such as temperature, pH, moisture, and the active conditions present in patients' mouths influence the rate of ion leaching from the SSCs and SM bands ( 8 , 9 ). The impact of the heat and sterilization procedures commonly used in dental clinics on the leaching of ions from SSCs and space maintainer bands has not been thoroughly studied. This knowledge gap necessitates further investigation, especially considering that fitting the SSCs and SM bands often involves trying multiple sizes until an optimal fit is achieved. This trial-and-error process results in unused crowns and bands that may be contaminated with blood, saliva, or infectious microorganisms ( 10 ). Therefore, sterilization of these crowns and bands before insertion into another patient's mouth is crucial to prevent cross-contamination ( 11 ). Numerous disinfection and sterilization techniques are available in dental clinics. However, autoclaves are widely regarded as the most effective for eliminating harmful pathogens from contaminated crowns ( 11 ). Therefore, this study aimed to evaluate the in vitro effect of autoclave sterilization on the release of Ni ions from pediatric SSCs and SM bands when immersed in artificial saliva. Materials and Methods This study was approved by the College of Dentistry Research Centre at King Saud University (FR0653). The in vitro experiments were conducted at the Dental University Hospital, Riyadh, Saudi Arabia. A total of 60 SM bands (manufactured by 3M™ Unitek™ made in the USA) and 60 SSC (manufactured by 3M™ ESPE™ stainless steel primary molar crowns, made in the USA) were studied. The SM bands and SSCs were divided into two equal groups: Group A comprised 60 samples (30 SM bands and 30 SSCs) that were not sterilized, whereas Group B consisted of 60 samples (30 SM bands and 30 SSCs) that underwent autoclave sterilization. The sterilization process for Group B involved the use of a V-120 Prevac steam sterilizer for 4 min, followed by drying for 15 min. Following sample preparation, each group (A and B) was immersed in 20 ml of artificial saliva (consisting of 0.8 g NaCl, 2.4 g KCl, 1.5 g NaH 2 PO 4 , 0.1 g Na 2 S, and 2 g CO (NH 2 ) 2 ), and the pH was adjusted to 6.75 ± 0.05. Each dish was sealed securely to prevent evaporation of the solution. The crowns and bands from each group were individually placed in separate dishes on a plastic stand to ensure no contact with any metallic material during the test. Each crown or band was placed in its own tube. The samples were stored in individual petri dishes and incubated at 37°C. The required amounts of saliva samples were drawn from each solution and analyzed separately on days 1, 7, 14, 21, and 42 to measure the concentration of released Ni ions in artificial saliva using a gas chromatography-mass spectrometry (GC-MS) machine (Thermo Fisher Scientific, USA). After each Ni ion concentration measurement, fresh artificial saliva samples were used to preserve the original composition of the artificial saliva and prevent saturation of the sample with released ions. This procedure was performed on days 7, 14, and 21; the saliva in the samples was replaced with new saliva. All dishes were gently agitated after immersing the SSCs or SM bands to ensure thorough coverage and achieve a uniform distribution of the solution. Seven days after the initial immersion of the SSCs and SM bands, samples of the artificial saliva were analyzed, and readings were recorded (second reading). This procedure was repeated for the third, fourth, and fifth readings on days 14, 21, and 42. Statistical analysis Data analysis was performed using a paired t-test. Statistical significance was set at a critical value of P = 0.05, with P < 0.05 considered statistically significant. All analyses were performed using the Statistical Package for the Social Sciences (SPSS) software version 29. Results The maximum release of Ni was observed in sterilized SSCs on day 7 (537811.3) and subsequently on day 14 (44036.2). Significantly higher amounts of ions were released in the sterilized group than in the non-sterilized group on days 7, 14, and 21 ( p < 0.05; Table 1 ). Table 1 Sample T-test table with Mean value and standard deviation of SSC before and after sterilization: Procedure N Mean ± SD p -value Day1 Non-sterilized 30 .00000 Sterilized 30 .00000 Day7 Non-sterilized 30 16685.5 ± 2792.1 .002* Sterilized 30 537811.3 ± 27740.5 Day14 Non-sterilized 30 4985.7 ± 617.7 < .001* Sterilized 30 44036.2 ± 5768.9 Day21 Non-sterilized 30 243.9 ± 80.7 .005* Sterilized 30 177.8 ± 43.1 Day42 Non-sterilized 30 .00000 Sterilized 30 .00000 *Statistically significant ( p < .05) Table 2 lists the Ni ions released from the SM bands. The highest release of Ni was observed in the sterilized SM bands on days 7 (233463.7) and 14 (12881.9). Significantly higher levels of ions were released in the sterilized group than in the nonsterilized group ( p < 0.05). Table 2 Sample T-test table with Mean value and standard deviation of SM before and after sterilization: Procedure N Mean ± SD p -value Day1 Non-sterilized 30 .00000 Sterilized 30 .00000 Day7 Non-sterilized 30 1214.2 ± 239.6 < .001* Sterilized 30 233463.7 ± 11142.4 Day14 Non-sterilized 30 769.4 ± 41.4 < .001* Sterilized 30 12881.9 ± 1095.7 Day21 Non-sterilized 30 36.4 ± 5.9 < .001* Sterilized 30 2239.6 ± 156.1 Day42 Non-sterilized 30 .00000 Sterilized 30 .00000 *Statistically significant ( p < .05) All samples of the SSC and SM bands exhibited a higher Ni release from the sterilized samples, as shown in Fig. 1 . However, on day 21, SSCs showed higher Ni leakage in the non-sterilized group ( p < 0.05). Tables 3 and 4 provide a comparison of Ni release between non-sterilized and sterilized SSCs and SM bands. The highest nickel concentration in the non-sterilized group was observed on day 7 for both crowns and bands, with crowns consistently showing the highest concentrations across all days ( p < 0.05). Table 3 Sample T-test table with Mean value and standard deviation of SM and SSC before sterilization: Group N Mean ± SD p -value Day7 Bands 30 1214.2 ± 239.6 < .001* crowns 30 16685.5 ± 2792.1 Day14 Bands 30 1214.2 ± 239.6 < .001* Crowns 30 4985.7 ± 617.7 Day21 Bands 30 36.4 ± 5.9 < .001* Crowns 30 243.9 ± 80.7 *Statistically significant ( p < .05) Table 4: Sample T-test table with Mean value and standard deviation of SM and SSC after sterilization: Group N Mean ± SD p -value. Day7 Bands 30 233463.7 ± 11142.4 .090 crowns 30 537811.3 ± 27740.5 Day14 Bands 30 12881.9 ± 1095.7 .001* Crowns 30 44036.2 ± 5768.9 Day21 Bands 30 2239.6 ± 156.1 .002* Crowns 30 177.8 ± 43.1 *Statistically significant ( p <.05) After sterilization on Day 7, the crowns exhibited a higher amount of Ni release, although this was not statistically significant ( p = 0.090). On day 14, the crowns showed a significantly higher release of ions (4985.7, p < 0.05), whereas on day 21, the bands showed a significantly higher release (2239.6 p < 0.05). For both groups of stainless steel crowns (SSCs) and space maintainer (SM) bands, no nickel ions were detected in the samples collected on day 42 (Tables 1 , 2 ) Discussion The use of SSCs and SM bands in pediatric dentistry has revolutionized the treatment of primary dentition. However, these nickel-containing appliances are expected to corrode because the alloys are exposed to varying pH levels and temperatures in the oral cavity ( 8 ). In the present study, a higher release of Ni ions from sterilized stainless steel crowns was observed on days 7 and 14 than from non-sterilized crowns. This phenomenon can be attributed to the combined effects of heat sterilization and corrosion on the sterilized SSCs. Sterilization processes can alter the surface chemistry of stainless steel ( 12 ) because they often involve high temperatures and/or harsh chemicals. These conditions can lead to the formation of a new surface layer on stainless steel, which affects its susceptibility to corrosion and ion leaching ( 13 ). Additionally, high temperatures can alter the microstructure of stainless steels, creating new grain boundaries and other metal defects that serve as pathways for ion leaching ( 14 ). The amount of Ni ions leached from stainless steel crowns after sterilization depends on several factors, such as the type of sterilization process used, sterilization temperature and duration, and the composition of the stainless steel ( 12 ). Similar findings regarding ion levels over time were reported by Tiwari et al., Kulkarni et al., and Amanna et al., who studied the release rates of ions and observed a decrease in Ni ion release from SSC as the study period progressed ( 7 , 8 , 15 ). This is consistent with the findings of the present study. The pH level plays a crucial role, as highlighted by Menek et al., who evaluated Ni release from SSCs immersed in artificial saliva for four weeks across various pH values. They noted a consistent increase in the Ni release over time under highly acidic conditions (pH = 2.5). Conversely, in more neutral environments (pH 6.25), the Ni release steadily decreased over time. The highest amount of Ni was released on the first day and decreased by the end of the study period. Overall, they observed that lower pH levels correlated with increased Ni release ( 16 ). This can be explained by the formation of a passivation layer. When a SSC is initially placed in the mouth, it comes into contact with various corrosive agents such as saliva, food, and drinks ( 8 ). These agents can dissolve the surface of stainless steel, resulting in the release of Ni ions into the surrounding environment ( 17 ). However, over time, a passivation layer develops on the surface of the SSC. This passivation layer is a thin oxidized film that acts as a protective barrier, shielding the underlying stainless steel from further corrosion ( 18 ). As this passivation layer became thicker, it inhibited the release of Ni ions from the SSC. This phenomenon likely explains why the initial ion leaching activity was the highest and then decreased over time in the study samples. In addition, anodic inhibitors are substances known to decrease the corrosion rates of metals such as titanium ( 19 ). These inhibitors play crucial roles in maintaining the stability of dental alloys. However, if a patient consumes a diet rich in acidic foods and beverages, the anodic inhibitors present in the saliva may become depleted. This depletion can accelerate the corrosion rate of metal alloys used in dental applications. Dietary habits and oral hygiene practices can significantly influence the longevity and performance of dental restorations. Furthermore, several other factors can influence the ion leaching activity in SSCs over time, including the composition of the stainless steel, manufacturing process, patient’s diet, and oral hygiene habits ( 20 ). The ion leaching activity of SSCs is a complex process that is influenced by multiple variables, including sterilization methods. These factors collectively determine the extent and rate of Ni ion release from SSCs in the oral environment. Our study found that the levels of Ni released from the samples were generally low and remained below toxic levels. However, even small amounts of Ni can trigger allergic reactions in susceptible patients owing to the allergenic properties of nickel and its prolonged presence in the oral cavity ( 8 ). Therefore, monitoring the release of nickel ions from dental materials is important to minimize potential allergic responses in patients. Conclusion The results of the present study suggest that patients undergoing SSCs or SM band placement should be screened for Ni allergy prior to cementation. These findings can guide dentists and patients in making informed decisions regarding dental care. Dentists should be mindful of the increased release of Ni ions from SSCs and SM after sterilization, which may influence their choice for children prone to allergies. This study provides valuable information to dentists by minimizing the need for trial placement of these devices. When sterilization is necessary, dentists can take precautions to minimize the release of Ni ions, such as using lower sterilization temperatures or shorter cycles. Additionally, parents can contribute by promoting good oral hygiene practices, including regular brushing and flossing, and limiting their children’s consumption of acidic foods and beverages to reduce their exposure to Ni ions. By considering these factors, dental practitioners and parents can collaborate to reduce the risk of allergic reactions and promote optimal dental health in pediatric patients undergoing SSC and SM band placement. Declarations Conflicts of interest statement: There are no conflicts of interest to declare. Ethics approval and consent to participate: Not applicable Consent for publication: Not applicable Availability of data and materials: The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request. Competing interests: None Funding: None Author’s contributions: N.A.: conceptualization, investigation, methodology, writing original draft, writing-review, and editing. H.A.: methodology, investigation, writing the original draft. S.A.: methodology, investigation, writing the original draft. N.A.: methodology, investigation, writing the original draft. N.A.: methodology, investigation, writing the original draft. M.A.: supervision, writing review, and editing. L.A..: supervision, writing review, and editing. All authors have read and agreed to the published version of the manuscript Acknowledgements: The authors would like to thank the College of Dentistry Research Center and Deanship of Scientific Research at King Saud University, Saudi Arabia for funding this research project References Setia V, Pandit IK, Srivastava N, Gugnani N, Sekhon HK. Space Maintainers in Dentistry: Past to Present. Clin Diagn Res. 2013;7(10):2402–5. 10.7860/JCDR/2013/6604.3539 . Ghadimi S, Seraj B, Ostadalipour A, Askari E. Comparison of Canine Overlap in Pediatric Patients Requiring Stainless Steel Crown Placement Under General Anesthesia Before and After the Procedure. Front Dent. 2019;16(1):78–87. 10.18502/fid.v16i1.1113 . Anusha K, Sridevi E, Sai Sankar AJ, Sridhar M, Sankar KS, Chowdary KH. An in Vitro evaluation of biodegradability of stainless steel crowns at various salivary pH. Indian J Dent Res. 2020;31(4):569–73. 10.4103/ijdr.IJDR_761_18 . 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PMID: 26028893; PMCID: PMC4441227. ohnson GK, Perry FU, Pelleu GB Jr.. Effect of four anticorrosive dips on the cutting efficiency of dental carbide burs. J Am Dent Assoc. 1987;114(5):648–50. 10.14219/jada.archive . Yu X, Ji Z. Grain Boundary in Oxide Scale During High-Temperature Metal Processing [Internet]. Study of Grain Boundary Character. InTech; 2017. http://dx.doi.org/10.5772/66211 Kulkarni P, Agrawal S, Bansal A, Jain A, Tiwari U, Anand A. Assessment of nickel release from various dental appliances used routinely in pediatric dentistry. Indian J Dent. 2016;7(2):81–5. 10.4103/0975-962X.184649 . Menek N, Başaran S, Karaman Y, Ceylan G, Tunç Ş. Investigation of Nickel Ion Release from Stainless Steel Crowns by Square Wave Voltammetry [Internet]. Vol. 7, Int. J. Electrochem. Sci. 2012. Kodaira H, Ohno K, Fukase N, Kuroda M, Adachi S, Kikuchi M, Asada Y. Release and systemic accumulation of heavy metals from preformed crowns used in restoration of primary teeth. J Oral Sci. 2013;55(2):161–5. 10.2334/josnusd.55.161 . Ramazani N, Ahmadi R, Darijani M. Assessment of nickel release from stainless steel crowns. J Dent (Tehran). 2014;11(3):328–34. PMID: 25628668; PMCID: PMC4290761. Vieira AC, Ribeiro AR, Rocha LA, Celis JP. Influence of pH and corrosion inhibitors on the tribocorrosion of titanium in artificial saliva. Wear. 2006;261(9):994–1001. 10.1016/J.WEAR.2006.03.031 . Oh KT, Kim KN. Ion release and cytotoxicity of stainless steel wires. Eur J Orthod. 2005;27(6):533–40. 10.1093/ejo/cji047 . Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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. 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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-4857451","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":356511523,"identity":"ec0eca80-678f-45a6-9ce1-9bb5f67a3b5b","order_by":0,"name":"Noura 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deciduous molars that have undergone pulpal therapy (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). These crowns protect primary molars by reducing the risk of post-operative symptoms (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). Their prefabricated design simplifies use and reduces chair time and cost (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn contrast, SM bands are metal bands placed on an abutment tooth as part of a space-maintaining appliance. They prevent space loss and tooth drift and maintain proper alignment (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). SM bands are indicated following the early loss of a deciduous tooth to preserve space for the eruption of permanent teeth. Its appropriate use can prevent the need for extensive orthodontic treatment (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe increasing popularity of SSCs and SM has been attributed to their ease of use and affordability. However, concerns have arisen regarding the nickel (Ni) content of these alloys, which has historically been linked to allergic reactions. This composition prompted inquiries into its biocompatibility, particularly regarding the potential release of Ni ions into the oral cavity after cementation (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). However, some studies have focused on determining whether factors such as temperature, pH, moisture, and the active conditions present in patients' mouths influence the rate of ion leaching from the SSCs and SM bands (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe impact of the heat and sterilization procedures commonly used in dental clinics on the leaching of ions from SSCs and space maintainer bands has not been thoroughly studied. This knowledge gap necessitates further investigation, especially considering that fitting the SSCs and SM bands often involves trying multiple sizes until an optimal fit is achieved. This trial-and-error process results in unused crowns and bands that may be contaminated with blood, saliva, or infectious microorganisms (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). Therefore, sterilization of these crowns and bands before insertion into another patient's mouth is crucial to prevent cross-contamination (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eNumerous disinfection and sterilization techniques are available in dental clinics. However, autoclaves are widely regarded as the most effective for eliminating harmful pathogens from contaminated crowns (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). Therefore, this study aimed to evaluate the in vitro effect of autoclave sterilization on the release of Ni ions from pediatric SSCs and SM bands when immersed in artificial saliva.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e This study was approved by the College of Dentistry Research Centre at King Saud University (FR0653). The in vitro experiments were conducted at the Dental University Hospital, Riyadh, Saudi Arabia.\u003c/p\u003e \u003cp\u003eA total of 60 SM bands (manufactured by 3M\u0026trade; Unitek\u0026trade; made in the USA) and 60 SSC (manufactured by 3M\u0026trade; ESPE\u0026trade; stainless steel primary molar crowns, made in the USA) were studied.\u003c/p\u003e \u003cp\u003eThe SM bands and SSCs were divided into two equal groups: Group A comprised 60 samples (30 SM bands and 30 SSCs) that were not sterilized, whereas Group B consisted of 60 samples (30 SM bands and 30 SSCs) that underwent autoclave sterilization. The sterilization process for Group B involved the use of a V-120 Prevac steam sterilizer for 4 min, followed by drying for 15 min.\u003c/p\u003e \u003cp\u003eFollowing sample preparation, each group (A and B) was immersed in 20 ml of artificial saliva (consisting of 0.8 g NaCl, 2.4 g KCl, 1.5 g NaH\u003csub\u003e2\u003c/sub\u003e PO\u003csub\u003e4\u003c/sub\u003e, 0.1 g Na\u003csub\u003e2\u003c/sub\u003eS, and 2 g CO (NH\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e), and the pH was adjusted to 6.75\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05. Each dish was sealed securely to prevent evaporation of the solution. The crowns and bands from each group were individually placed in separate dishes on a plastic stand to ensure no contact with any metallic material during the test. Each crown or band was placed in its own tube.\u003c/p\u003e \u003cp\u003eThe samples were stored in individual petri dishes and incubated at 37\u0026deg;C. The required amounts of saliva samples were drawn from each solution and analyzed separately on days 1, 7, 14, 21, and 42 to measure the concentration of released Ni ions in artificial saliva using a gas chromatography-mass spectrometry (GC-MS) machine (Thermo Fisher Scientific, USA).\u003c/p\u003e \u003cp\u003eAfter each Ni ion concentration measurement, fresh artificial saliva samples were used to preserve the original composition of the artificial saliva and prevent saturation of the sample with released ions. This procedure was performed on days 7, 14, and 21; the saliva in the samples was replaced with new saliva. All dishes were gently agitated after immersing the SSCs or SM bands to ensure thorough coverage and achieve a uniform distribution of the solution. Seven days after the initial immersion of the SSCs and SM bands, samples of the artificial saliva were analyzed, and readings were recorded (second reading). This procedure was repeated for the third, fourth, and fifth readings on days 14, 21, and 42.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eData analysis was performed using a paired t-test. Statistical significance was set at a critical value of P\u0026thinsp;=\u0026thinsp;0.05, with P\u0026thinsp;\u0026lt;\u0026thinsp;0.05 considered statistically significant. All analyses were performed using the Statistical Package for the Social Sciences (SPSS) software version 29.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe maximum release of Ni was observed in sterilized SSCs on day 7 (537811.3) and subsequently on day 14 (44036.2). Significantly higher amounts of ions were released in the sterilized group than in the non-sterilized group on days 7, 14, and 21 (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05; Table\u0026nbsp;\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\u003eSample T-test table with Mean value and standard deviation of SSC before and after sterilization:\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\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=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eProcedure\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.00000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.00000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16685.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2792.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e.002*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e537811.3\u0026thinsp;\u0026plusmn;\u0026thinsp;27740.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4985.7\u0026thinsp;\u0026plusmn;\u0026thinsp;617.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e44036.2\u0026thinsp;\u0026plusmn;\u0026thinsp;5768.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e243.9\u0026thinsp;\u0026plusmn;\u0026thinsp;80.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e.005*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e177.8\u0026thinsp;\u0026plusmn;\u0026thinsp;43.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.00000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.00000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003e*Statistically significant (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.05)\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\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e lists the Ni ions released from the SM bands. The highest release of Ni was observed in the sterilized SM bands on days 7 (233463.7) and 14 (12881.9). Significantly higher levels of ions were released in the sterilized group than in the nonsterilized group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\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\u003eSample T-test table with Mean value and standard deviation of SM before and after sterilization:\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\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=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eProcedure\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.00000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.00000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1214.2\u0026thinsp;\u0026plusmn;\u0026thinsp;239.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e233463.7\u0026thinsp;\u0026plusmn;\u0026thinsp;11142.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e769.4\u0026thinsp;\u0026plusmn;\u0026thinsp;41.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12881.9\u0026thinsp;\u0026plusmn;\u0026thinsp;1095.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e36.4\u0026thinsp;\u0026plusmn;\u0026thinsp;5.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2239.6\u0026thinsp;\u0026plusmn;\u0026thinsp;156.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-sterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.00000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSterilized\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.00000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003e*Statistically significant (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.05)\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\u003eAll samples of the SSC and SM bands exhibited a higher Ni release from the sterilized samples, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. However, on day 21, SSCs showed higher Ni leakage in the non-sterilized group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eTables\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and 4 provide a comparison of Ni release between non-sterilized and sterilized SSCs and SM bands. The highest nickel concentration in the non-sterilized group was observed on day 7 for both crowns and bands, with crowns consistently showing the highest concentrations across all days (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\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\u003eSample T-test table with Mean value and standard deviation of SM and SSC before sterilization:\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\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=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGroup\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBands\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1214.2\u0026thinsp;\u0026plusmn;\u0026thinsp;239.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ecrowns\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16685.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2792.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBands\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1214.2\u0026thinsp;\u0026plusmn;\u0026thinsp;239.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCrowns\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4985.7\u0026thinsp;\u0026plusmn;\u0026thinsp;617.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDay21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBands\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e36.4\u0026thinsp;\u0026plusmn;\u0026thinsp;5.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCrowns\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e243.9\u0026thinsp;\u0026plusmn;\u0026thinsp;80.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003e*Statistically significant (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.05)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"691\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"98.98550724637681%\" colspan=\"5\" style=\"width: 52.6579%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 4:\u003c/strong\u003e Sample T-test table with Mean value and standard deviation of SM and SSC after sterilization:\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"19.797687861271676%\" style=\"width: 9.786%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.797687861271676%\" style=\"width: 10.1743%;\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.797687861271676%\" style=\"width: 9.9413%;\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.85549132947977%\" style=\"width: 12.1936%;\"\u003e\n \u003cp\u003eMean\u0026nbsp;\u0026plusmn;\u0026nbsp;SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.739884393063583%\" style=\"width: 10.6403%;\"\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"19.797687861271676%\" rowspan=\"2\" style=\"width: 9.786%;\"\u003e\n \u003cp\u003eDay7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.797687861271676%\" style=\"width: 10.1743%;\"\u003e\n \u003cp\u003eBands\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.797687861271676%\" style=\"width: 9.9413%;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.85549132947977%\" style=\"width: 12.1936%;\"\u003e\n \u003cp\u003e233463.7\u0026nbsp;\u0026plusmn;\u0026nbsp;11142.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.739884393063583%\" rowspan=\"2\" style=\"width: 10.6403%;\"\u003e\n \u003cp\u003e.090\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"30.242825607064017%\" style=\"width: 10.1743%;\"\u003e\n \u003cp\u003ecrowns\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"30.242825607064017%\" style=\"width: 9.9413%;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"37.969094922737305%\" style=\"width: 12.1936%;\"\u003e\n \u003cp\u003e537811.3\u0026nbsp;\u0026plusmn;\u0026nbsp;27740.5\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"19.797687861271676%\" rowspan=\"2\" style=\"width: 9.786%;\"\u003e\n \u003cp\u003eDay14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.797687861271676%\" style=\"width: 10.1743%;\"\u003e\n \u003cp\u003eBands\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.797687861271676%\" style=\"width: 9.9413%;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.85549132947977%\" style=\"width: 12.1936%;\"\u003e\n \u003cp\u003e12881.9\u0026nbsp;\u0026plusmn;\u0026nbsp;1095.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.739884393063583%\" rowspan=\"2\" style=\"width: 10.6403%;\"\u003e\n \u003cp\u003e.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"30.242825607064017%\" style=\"width: 10.1743%;\"\u003e\n \u003cp\u003eCrowns\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"30.242825607064017%\" style=\"width: 9.9413%;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"37.969094922737305%\" style=\"width: 12.1936%;\"\u003e\n \u003cp\u003e44036.2\u0026nbsp;\u0026plusmn;\u0026nbsp;5768.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"19.797687861271676%\" rowspan=\"2\" style=\"width: 9.786%;\"\u003e\n \u003cp\u003eDay21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.797687861271676%\" style=\"width: 10.1743%;\"\u003e\n \u003cp\u003eBands\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.797687861271676%\" style=\"width: 9.9413%;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.85549132947977%\" style=\"width: 12.1936%;\"\u003e\n \u003cp\u003e2239.6\u0026nbsp;\u0026plusmn;\u0026nbsp;156.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.739884393063583%\" rowspan=\"2\" style=\"width: 10.6403%;\"\u003e\n \u003cp\u003e.002*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"30.242825607064017%\" style=\"width: 10.1743%;\"\u003e\n \u003cp\u003eCrowns\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"30.242825607064017%\" style=\"width: 9.9413%;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"37.969094922737305%\" style=\"width: 12.1936%;\"\u003e\n \u003cp\u003e177.8\u0026nbsp;\u0026plusmn;\u0026nbsp;43.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"98.98697539797395%\" colspan=\"5\" style=\"width: 53.5123%;\"\u003e\n \u003cp\u003e*Statistically significant (\u003cem\u003ep\u0026nbsp;\u003c/em\u003e\u0026lt;.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\u003cp\u003eAfter sterilization on Day 7, the crowns exhibited a higher amount of Ni release, although this was not statistically significant (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.090). On day 14, the crowns showed a significantly higher release of ions (4985.7, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), whereas on day 21, the bands showed a significantly higher release (2239.6 \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003eFor both groups of stainless steel crowns (SSCs) and space maintainer (SM) bands, no nickel ions were detected in the samples collected on day 42 (Tables\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e,\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe use of SSCs and SM bands in pediatric dentistry has revolutionized the treatment of primary dentition. However, these nickel-containing appliances are expected to corrode because the alloys are exposed to varying pH levels and temperatures in the oral cavity (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn the present study, a higher release of Ni ions from sterilized stainless steel crowns was observed on days 7 and 14 than from non-sterilized crowns. This phenomenon can be attributed to the combined effects of heat sterilization and corrosion on the sterilized SSCs. Sterilization processes can alter the surface chemistry of stainless steel (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e) because they often involve high temperatures and/or harsh chemicals. These conditions can lead to the formation of a new surface layer on stainless steel, which affects its susceptibility to corrosion and ion leaching (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). Additionally, high temperatures can alter the microstructure of stainless steels, creating new grain boundaries and other metal defects that serve as pathways for ion leaching (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe amount of Ni ions leached from stainless steel crowns after sterilization depends on several factors, such as the type of sterilization process used, sterilization temperature and duration, and the composition of the stainless steel (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). Similar findings regarding ion levels over time were reported by Tiwari et al., Kulkarni et al., and Amanna et al., who studied the release rates of ions and observed a decrease in Ni ion release from SSC as the study period progressed (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). This is consistent with the findings of the present study.\u003c/p\u003e \u003cp\u003eThe pH level plays a crucial role, as highlighted by Menek et al., who evaluated Ni release from SSCs immersed in artificial saliva for four weeks across various pH values. They noted a consistent increase in the Ni release over time under highly acidic conditions (pH\u0026thinsp;=\u0026thinsp;2.5). Conversely, in more neutral environments (pH 6.25), the Ni release steadily decreased over time. The highest amount of Ni was released on the first day and decreased by the end of the study period. Overall, they observed that lower pH levels correlated with increased Ni release (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis can be explained by the formation of a passivation layer. When a SSC is initially placed in the mouth, it comes into contact with various corrosive agents such as saliva, food, and drinks (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). These agents can dissolve the surface of stainless steel, resulting in the release of Ni ions into the surrounding environment (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e). However, over time, a passivation layer develops on the surface of the SSC. This passivation layer is a thin oxidized film that acts as a protective barrier, shielding the underlying stainless steel from further corrosion (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). As this passivation layer became thicker, it inhibited the release of Ni ions from the SSC. This phenomenon likely explains why the initial ion leaching activity was the highest and then decreased over time in the study samples.\u003c/p\u003e \u003cp\u003eIn addition, anodic inhibitors are substances known to decrease the corrosion rates of metals such as titanium (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e). These inhibitors play crucial roles in maintaining the stability of dental alloys. However, if a patient consumes a diet rich in acidic foods and beverages, the anodic inhibitors present in the saliva may become depleted. This depletion can accelerate the corrosion rate of metal alloys used in dental applications. Dietary habits and oral hygiene practices can significantly influence the longevity and performance of dental restorations.\u003c/p\u003e \u003cp\u003eFurthermore, several other factors can influence the ion leaching activity in SSCs over time, including the composition of the stainless steel, manufacturing process, patient\u0026rsquo;s diet, and oral hygiene habits (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e). The ion leaching activity of SSCs is a complex process that is influenced by multiple variables, including sterilization methods. These factors collectively determine the extent and rate of Ni ion release from SSCs in the oral environment.\u003c/p\u003e \u003cp\u003eOur study found that the levels of Ni released from the samples were generally low and remained below toxic levels. However, even small amounts of Ni can trigger allergic reactions in susceptible patients owing to the allergenic properties of nickel and its prolonged presence in the oral cavity (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). Therefore, monitoring the release of nickel ions from dental materials is important to minimize potential allergic responses in patients.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe results of the present study suggest that patients undergoing SSCs or SM band placement should be screened for Ni allergy prior to cementation. These findings can guide dentists and patients in making informed decisions regarding dental care. Dentists should be mindful of the increased release of Ni ions from SSCs and SM after sterilization, which may influence their choice for children prone to allergies.\u003c/p\u003e \u003cp\u003eThis study provides valuable information to dentists by minimizing the need for trial placement of these devices. When sterilization is necessary, dentists can take precautions to minimize the release of Ni ions, such as using lower sterilization temperatures or shorter cycles. Additionally, parents can contribute by promoting good oral hygiene practices, including regular brushing and flossing, and limiting their children\u0026rsquo;s consumption of acidic foods and beverages to reduce their exposure to Ni ions.\u003c/p\u003e \u003cp\u003eBy considering these factors, dental practitioners and parents can collaborate to reduce the risk of allergic reactions and promote optimal dental health in pediatric patients undergoing SSC and SM band placement.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eConflicts of interest statement:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere are no conflicts of interest to declare.\u003c/p\u003e\n\u003cp\u003eEthics approval and consent to participate: Not applicable\u003c/p\u003e\n\u003cp\u003eConsent for publication: Not applicable\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials: The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003eCompeting interests:\u0026nbsp;None\u003c/p\u003e\n\u003cp\u003eFunding:\u0026nbsp;None\u003c/p\u003e\n\u003cp\u003eAuthor\u0026rsquo;s contributions:\u0026nbsp;N.A.: conceptualization, investigation, methodology, writing original draft, writing-review, and editing. H.A.: methodology, investigation, writing the original draft. S.A.: methodology, investigation, writing the original draft. N.A.: methodology, investigation, writing the original draft. N.A.: methodology, investigation, writing the original draft. M.A.: supervision, writing review, and editing. L.A..: supervision, writing review, and editing. All authors have read and agreed to the published version of the manuscript\u003c/p\u003e\n\u003cp\u003eAcknowledgements: The authors would like to thank the College of Dentistry Research Center and Deanship of Scientific Research at King Saud University, Saudi Arabia for funding this research project\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSetia V, Pandit IK, Srivastava N, Gugnani N, Sekhon HK. Space Maintainers in Dentistry: Past to Present. 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Eur J Orthod. 2005;27(6):533\u0026ndash;40. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1093/ejo/cji047\u003c/span\u003e\u003cspan address=\"10.1093/ejo/cji047\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Nickle ion release, Auto-clave sterilization of stainless steel, Ion leaching of stainless steel crowns, space maintainer bands","lastPublishedDoi":"10.21203/rs.3.rs-4857451/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4857451/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eAim\u003c/h2\u003e \u003cp\u003eThis study aimed to investigate the effect of autoclave sterilization on the leaching of nickel ions from stainless steel crowns and space-maintainer bands used in pediatric dentistry.\u003c/p\u003e\u003ch2\u003eMaterials and Methods\u003c/h2\u003e \u003cp\u003eSixty space maintainer bands and 60 stainless steel crowns were divided into sterilized and non-sterilized groups. These samples were immersed in artificial saliva, placed in individual petri dishes, and then incubated at 37\u0026deg;C. The samples were analyzed for 42 d using a gas chromatography-mass spectrometry (GC-MS) machine to quantify the release of nickel ions.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eNickel release was higher in the sterilized samples than in the non-sterilized samples for both space maintainer bands and stainless steel crowns. This trend persisted throughout most days of the experiment, with a peak release observed on day 7. The sterilized group showed significantly higher levels of ion release than the non-sterilized group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThis study suggests that nickel allergy testing may be advisable before placing stainless steel crowns or space maintainers, particularly for patients at risk of allergies. Dentists should be mindful of the increased nickel release observed from sterilized crowns and bands, as this information could influence treatment decisions, especially in children who are predisposed to allergies.\u003c/p\u003e","manuscriptTitle":"Does Auto-clave Sterilization Affect Nickle Ion Release of Stainless Steel Crowns and Space Maintainer Bands?","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-10-15 10:52:43","doi":"10.21203/rs.3.rs-4857451/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ab2f83eb-413b-4cdd-a6f2-e4df1aedc833","owner":[],"postedDate":"October 15th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-11-07T19:53:29+00:00","versionOfRecord":[],"versionCreatedAt":"2024-10-15 10:52:43","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4857451","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4857451","identity":"rs-4857451","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}