Simultaneous detection of dental caries and fissure sealant in intraoral photos by deep learning: a pilot study.

BACKGROUND: Deep learning, as an artificial intelligence method has been proved to be powerful in analyzing images. The purpose of this study is to construct a deep learning-based model (ToothNet) for the simultaneous detection of dental caries and fissure sealants in intraoral photos. METHODS: A total of 1020 intraoral photos were collected from 762 volunteers. Teeth, caries and sealants were annotated by two endodontists using the LabelMe tool. ToothNet was developed by modifying the YOLOX framework for simultaneous detection of caries and fissure sealants. The area under curve (AUC) in the receiver operating characteristic curve (ROC) and free-response ROC (FROC) curves were used to evaluate model performance in the following aspects: (i) classification accuracy of detecting dental caries and fissure sealants from a photograph (image-level); and (ii) localization accuracy of the locations of predicted dental caries and fissure sealants (tooth-level). The performance of ToothNet and dentist with 1year of experience (1-year dentist) were compared at tooth-level and image-level using Wilcoxon test and DeLong test. RESULTS: At the image level, ToothNet achieved an AUC of 0.925 (95% CI, 0.880-0.958) for caries detection and 0.902 (95% CI, 0.853-0.940) for sealant detection. At the tooth level, with a confidence threshold of 0.5, the sensitivity, precision, and F1-score for caries detection were 0.807, 0.814, and 0.810, respectively. For fissure sealant detection, the values were 0.714, 0.750, and 0.731. Compared with ToothNet, the 1-year dentist had a lower F1 value (0.599, p < 0.0001) and AUC (0.749, p < 0.0001) in caries detection, and a lower F1 value (0.727, p = 0.023) and similar AUC (0.829, p = 0.154) in sealant detection. CONCLUSIONS: The proposed deep learning model achieved multi-task simultaneous detection in intraoral photos and showed good performance in the detection of dental caries and fissure sealants. Compared with 1-year dentist, the model has advantages in caries detection and is equivalent in fissure sealants detection.

Vitamin D deficiency and chronological hypoplasia with hypomineralisation: a case report.

Patients being reported for vitamin D deficiency (VDD) are increasing, particularly among the children and adolescents. This study aims to manifest the clinical and dental evaluations of a child with VDD, referred to the dental office. A 10-year-old British Asian boy was referred to the paediatric specialist dentistry clinic by the general dentist for dental management. The medical history depicted that the patient was diagnosed with VDD, secondary hyperparathyroidism and delayed growth. Moreover, his mother had the VDD during pregnancy. The patient was breast fed and had rickets in infancy. He was prescribed vitamin D supplements at the age of 16 months. He had received multiple dental treatments under local anaesthesia but with limited cooperation. Clinical examination revealed that the patient had chronological enamel hypoplasia shown as bands at the occlusal third on specific teeth. Suboptimal hygiene with general plaque induced gingivitis, dental caries in permanent and primary teeth, and delayed the teeth eruption. Preventions included appropriate oral hygiene and dietary advice, fluoride varnish application and fissure sealant placement. The treatments included anterior direct composite restoration, posterior composite restoration, stainless steel crowns and extractions. Thorough medical history is essential to understand the underlying causes of dental defects. Early dental intervention can restore the patient appearance and function and prevent further dental damage.

Research interest on dental sealant in dentistry based on the 100 most cited articles: bibliometric analysis.

The aim of this study was to identify and analyze the characteristics of the 100 most cited articles about dental sealants (DS) in dentistry. In September 2023, a search was performed in the Web of Science Core Collection (WoS-CC) database. The following information was extracted from each article: number and density of citations, year of publication, authorship, journal, impact factor, keywords, study design, theme, continent, country, and institution. The citations of the WoS-CC were compared with those of the Scopus and Google Scholar databases. The VOSviewer software was used to generate collaborative networks. The number of citations ranged from 33 to 205. The articles were published between 1961 and 2016. Buonocore MG (7%) was the most prominent author among the most cited. The Journal of the American Dental Association was the most frequent journal (25%) and Journal of Dental Research (7.6) had the highest impact factor. Most studies had interventional (41%) and laboratory (31%) designs, mainly addressing DS effectiveness in the prevention and control of dental caries (86%). There was a predominance of publications from North America (46%) and the USA was the country with the highest number of articles (44%). The most frequent institutions were the Centers for Disease Control and Prevention (USA) and the University of Rochester (USA) (6% each). "Retention" was the most frequent keyword. In conclusion, the 100 most cited articles were mostly interventional and laboratory studies, addressing the retention and efficacy of DS. Most of the articles were concentrated in North America and Europe, demonstrating a little collaboration from other continents.

Detection of pit and fissure sealant microleakage using quantitative light-induced fluorescence technology: an in vitro study.

This in vitro study aimed to evaluate the feasibility of quantitative light-induced fluorescence (QLF) technology for detecting the presence and severity of microleakage of pit and fissure sealants. The areas of interest (AOIs) were 160 pits and fissures of 40 extracted permanent teeth. Fluorescent images were acquired using a QLF device, and the maximum fluorescence loss ΔFmax of each AOI was analyzed. After staining and cross-sectioning of the teeth, histological dye penetration was scored on a scale of 0 to 3. The relationship between ΔFmax and microleakage depth was analyzed, and the areas under the curve (AUCs) were calculated. The │ΔFmax│ increased as microleakage depth increased. The ΔFmax values of microleakage areas showed a strong significant correlation with the histological scores of dye penetration (r = - 0.72, P = 0.001). AUC analysis showed a high diagnostic accuracy for microleakage depth (AUC = 0.83-0.91). The highest AUC of 0.91 was found when differentiating the outer half microleakage of the sealant (histological score 0 vs. 1-3). QLF technology is effective in assessing the presence and severity of microleakage, suggesting its potential for noninvasive detection and monitoring of sealant microleakage in clinical settings.

Improvements in appropriate placement of dental sealants after implementation of a clinical decision support system.

BACKGROUND: Dental sealants are effective for the prevention of caries in children at elevated risk levels, and increasing the proportion of children and adolescents who have dental sealants on 1 or more molars is a Healthy People 2030 objective. Electronic health record (EHR)-based clinical decision support systems (CDSSs) have the ability to improve patient care. A dental quality measure related to dental sealant placement for children at elevated risk of caries was targeted for improvement using a CDSS. METHODS: A validated dental quality measure was adapted to assess a patient's need for dental sealant placement. A CDSS was implemented to advise care team members whether a child was at elevated risk of developing caries and had sealant-eligible first or second molars. Data on dental sealant placement at examination visits during a 5-year period were analyzed, including 32 months before CDSS implementation and 28 months after CDSS implementation. RESULTS: From January 1, 2018, through December 31, 2022, the authors assessed 59,047 examination visits for children at elevated risk of developing caries and with sealant-eligible teeth. With the implementation of a CDSS and training to support the clinical care team members in September 2020, the appropriate placement of dental sealants at examination visits increased from 27% through 60% (P < .00001). CONCLUSIONS: Integration of a CDSS into the EHR as part of a quality improvement program was effective in increasing the delivery of sealants in eligible first and second molars of children aged 5 through 15 years and considered at high risk of developing caries. PRACTICAL IMPLICATIONS: An EHR-based CDSS can be implemented to improve standardization and provide timely and appropriate patient care in dental practices.

Associations between school-based fluoride mouth-rinse program, medical-dental expense subsidy policy, and children's oral health in Japan: an ecological study.

BACKGROUND: Dental caries are a common non-communicable disease among children. As a public health measure at the prefectural level, school-based fluoride mouth-rinse (S-FMR) program, medical/dental expense subsidy policies, and other factors may reduce the incidence of dental caries and tooth loss. Prefectures focusing on promoting oral health policies may promote both, but the interaction effect of implementing both subsidy policies and S-FMR at the prefectural level on caries prevention has not yet been examined. METHODS: We conducted an ecological study using two-wave panel data, prefecture-level aggregated data in Japan for 2016 and 2018. Coefficient and 95% confidence intervals (CI) were calculated for the dependent variables for oral health using mixed-effects linear regression analysis adjusted for possible confounders. Two dependent variables were used; the standardized claim ratio (SCR) of deciduous tooth extraction and 12-year-olds' decayed, missing, or filled permanent teeth (DMFT). Four independent variables were S-FMR, the SCR of dental sealants, prefectural income per person, and subsidy policy in three models: co-payment until children enter elementary school (n = 23), no co-payment until children enter elementary school (n = 7), and co-payment continuing beyond elementary school (n = 17). The effects of six interaction terms, each representing a unique pairing from the four independent variables, were individually calculated. RESULTS: S-FMR was negatively associated with the SCR of deciduous tooth extractions and DMFT (coefficient = -0.11, 95% CI -0.20; -0.01 and coefficient = -0.003, 95% CI -0.005; -0.001, respectively). No co-payment until children enter elementary school was positively associated with the SCR of deciduous tooth extraction compared to co-payment until children enter elementary school(coefficient = 11.42, 95% CI 3.29; 19.55). SCR of dental sealants was positively associated with the SCR of deciduous tooth extractions (coefficient = 0.12, 95% CI 0.06; 0.19) but negatively associated with DMFT (coefficient = -0.001, 95% CI -0.003; -0.0001). Per capita prefectural income was positively associated with the SCR of deciduous tooth extractions(coefficient = 0.01, 95% CI 0.001; 0.02). No interaction was found between S-FMR and the subsidy policy at both outcomes. CONCLUSION: High S-FMR utilization and no co-payment until children enter elementary school were associated with fewer deciduous tooth extractions. Also, S-FMR and dental sealant were associated with decreased DMFT.

Noninferiority of Silver Diamine Fluoride vs Sealants for Reducing Dental Caries Prevalence and Incidence: A Randomized Clinical Trial.

Importance: Dental caries is the world's most prevalent noncommunicable disease and a source of health inequity; school dental sealant programs are a common preventive measure. Silver diamine fluoride (SDF) may provide an alternative therapy to prevent and control caries if shown to be noninferior to sealant treatment. Objective: To determine whether school-based application of SDF is noninferior to dental sealants and atraumatic restorative treatment (ART) in the prevalence of dental caries. Design, Setting, and Participants: The Silver Diamine Fluoride Versus Therapeutic Sealants for the Arrest and Prevention of Dental Caries in Low-Income Minority Children (CariedAway) study was a pragmatic noninferiority cluster-randomized clinical trial conducted from February 2018 to June 2023 to compare silver diamine fluoride vs therapeutic sealants for the arrest and prevention of dental caries. Children at primary schools in New York, New York, with at least 50% of the student population reporting as Black or Hispanic and at least 80% receiving free or reduced lunch were included. This population was selected as they are at the highest risk of caries in New York. Students were randomized to receive either SDF or sealant with ART; those aged 5 to 13 years were included in the analysis. Treatment was provided at every visit based on need, and the number of visits varied by child. Schools with preexisting oral health programs were excluded, as were children who did not speak English. Of 17 741 students assessed for eligibility, 7418 were randomized, and 4100 completed follow-up and were included in the final analysis. Interventions: Participants were randomized at the school level to receive either a 38% concentration SDF solution or glass ionomer sealants and ART. Each participant also received fluoride varnish. Main Outcomes and Measures: Primary study outcomes were the prevalence and incidence of dental caries. Results: A total of 7418 children (mean [SD] age, 7.58 [1.90] years; 4006 [54.0%] female; 125 [1.7%] Asian, 1246 [16.8%] Black, 3648 [49.2%] Hispanic, 153 [2.1%] White, 114 [1.5%] multiple races or ethnicities, 90 [1.2%] other [unspecified], 2042 [27.5%] unreported) were enrolled and randomized to receive either SDF (n = 3739) or sealants with ART (n = 3679). After initial treatment, 4100 participants (55.0%) completed at least 1 follow-up observation. The overall baseline prevalence of dental caries was approximately 27.2% (95% CI, 25.7-28.6). The odds of decay prevalence decreased longitudinally (odds ratio [OR], 0.79; 95% CI, 0.75-0.83) and SDF was noninferior compared to sealants and ART (OR, 0.94; 95% CI, 0.80-1.11). The crude incidence of dental caries in children treated with SDF was 10.2 per 1000 tooth-years vs 9.8 per 1000 tooth-years in children treated with sealants and ART (rate ratio, 1.05; 95% CI, 0.97-1.12). Conclusions and Relevance: In this school-based pragmatic randomized clinical trial, application of SDF resulted in nearly identical caries incidence compared to dental sealants and ART and was noninferior in the longitudinal prevalence of caries. These findings suggest that SDF may provide an effective alternative for use in school caries prevention. Trial Registration: ClinicalTrials.gov Identifier: NCT03442309.

Comparing the effectiveness of caries arrest by micro-operative treatment to operative treatment: A 2-year randomized controlled clinical trial.

OBJECTIVES: To compare the effectiveness of caries arrest by micro-operative treatment (sealing) to operative treatment (flowable resin composite restoration) through a 2-year randomized controlled clinical trial. MATERIALS AND METHODS: A prospective randomized controlled trial was conducted among 7-9-year-old children. At baseline, 630 subjects were screened and 92 children who had at least one carious lesion classified as ICDAS 3 on the pit and fissure of first permanent molar were included. Then they were randomly assigned to the sealant group (73 lesions) and the flowable resin composite group (76 lesions) to receive the corresponding intervention. Lesions status in each group was evaluated every 6 months up to 24 months. Clinical progression of dental caries and materials retention were the outcomes used for group comparisons at p-value < 0.05. RESULTS: After 24 months, three lesions (4.1%) in the sealant group clinically progressed to dentin caries. No lesion in the flowable composite group was observed a progression. The results of Life-table survival analysis show that the cumulative caries arrest rate had no statistically significant difference between the two groups (p = 0.075). However, the cumulative retention rate was 57.5% in the sealant group and 92.1% in the flowable composite group, with significant differences (p < 0.001). The multilevel mixed model showed the sealant had higher risk of retention failure than the flowable composite (OR = 8.66, p < 0.001), while tooth position did not influence material retention (p = 0.083). In addition, the results of Fisher Exact test show that dentin lesions had more retention failure than enamel lesions in the sealant group (p = 0.026). CONCLUSION: Although sealing microcavitated carious lesions of the first permanent molar achieved lower retention rate than resin composite restoration, both sealing and restoration effectively arrested caries progression for two years. CLINICAL RELEVANCE: To preserving dental structure and delaying or eliminating the need for operative procedures, microcavitated carious lesion can be arrested by sealing. TRIAL REGISTRATION: Registered at http://www.chictr.org.cn ; Feb 15th, 2020; No. ChiCTR2000029862.

Evaluation of the amount of residual monomer released from different flowable composite resins.

Today, resin materials are used in the restoration of permanent and deciduous teeth or as fissure sealants. The materials can contain different types of monomers (Bis-GMA, UDMA, TEGDMA). These monomers can be released into the oral cavity after polymerization. Residual monomers released from resin-containing restorative materials after polymerization have been reported to have negative effects on mechanical properties. The aim of our study is to evaluate the amount of residual monomers released after polymerization of different flowable composite resin materials using two different modes of LED light source. Composite disc samples (8 mm diameter/2 mm depth) prepared for each material group were polymerized using two different modes of the LED light device (Standard mode and extra power mode). HPLC (High Performance Liquid Chromatography) device was used to measure the amount of residual monomer release at 1 h, 1 day, 3 days and 7 days periods. Pairwise comparison of the differences between the materials was performed by Post-hoc test. For each residual monomer, the Kruskal Wallis test was used to analyze the difference between the materials in standard mode and the difference between the materials in extra power mode. According to the results of the study; Grandio flow flowable composite showed the highest release of TEGDMA and Bis-GMA while SDR® Flow flowable composite showed the lowest release of TEGDMA, Bis-GMA and UDMA. For all materials, the extra power mode resulted in more residual monomer release. TEGDMA and Bis-GMA release was detected in all tested flowable composites at all time periods.

Exploring Recent Decreases in First Molar Sealants among US Children.

Analyses of National Health and Nutrition Examination Survey (NHANES) data suggested a significant decrease in sealant prevalence among children between 2011 to 2014 and 2015 to 2018. We explore whether this decrease could be associated with possible changes in 1) clinical sealant delivery, 2) dental materials (i.e., increased use of glass ionomer [GI] sealants resulting in an inability to detect sealant fragments that still provide preventive benefits or increased use of composite restorations leading to misclassifying sealants as restorations), and 3) examination sensitivity and specificity. We used NHANES data to estimate the prevalences of sealants, untreated caries, and restorations in ≥1 first permanent molar among children aged 7 to 10 y and used Medical Expenditure Panel Survey data to estimate the annual clinical delivery of sealants and fluoride treatments. We examined changes in outcomes between 2 periods (P < 0.05) controlling for selected sociodemographic characteristics. NHANES sealant examination quality was based on the reference examiner's replicate examinations. The adjusted prevalence of sealants decreased relatively by 27.5% (46.6% vs. 33.8%). Overall, untreated caries decreased. Untreated caries and restoration decreased among children without sealants. Annual clinical sealant delivery did not change, whereas fluoride treatment delivery increased. The decrease in sealant prevalence held when assessed for various age ranges and NHANES cycle combinations. While sealant examination specificity remained similar between the periods, sensitivity (weighted by the proportion of exams by each examiner) decreased relatively by 17.4% (0.92 vs. 0.76). These findings suggest that decreased sealant prevalence was not supported by decreased clinical sealant delivery nor increased use of composite restorations. Decreased examination sensitivity, which could be due to an increased use of GI sealants, could contribute to the decrease in sealant prevalence. The decrease in caries among children without sealants could suggest the increased use of GI sealants. However, we could not rule out that the decrease in caries could be attributable to increased fluoride treatment delivery.

Dental Hygiene Students' Knowledge, Understanding and Intended Use of Caries Preventive Regimens and Community Water Fluoridation.

Purpose The purpose of this study was to determine dental hygiene students' perspectives regarding their knowledge and understanding about caries prevention strategies and their intention to use these regimens in clinical practice. Dental hygienists' knowledge and understanding of caries prevention is critical because they are the primary providers of these regimens and the relevant education.Methods This 2019 national cross-sectional online survey was designed by the University of Maryland (UMD), structured by the ADA staff for online administration, distributed and collected by the American Dental Hygienists' Association (ADHA) to 9533 email addresses, and de-identified response data were analyzed by UMD. The survey included questions on three caries preventive regimens: fluoride varnish, dental sealants, and silver diamine fluoride (SDF), and items on community water fluoridation (CWF), respondent's demographics and intent to use the regimens. Statistical analyses included descriptive statistics and analysis of variance. Significance was set at p<0.05.Results Of the 235 surveys returned (response rate 2.5%) the majority were female, White and born in the United States. Over half were in associate degree programs; nearly a third were in baccalaureate programs. Respondents reported greater knowledge/understanding and intention to use fluoride varnish and dental sealants than SDF. Less than half (44.7%) reported knowledge/understanding of SDF and only 22.6% had a high level of confidence regarding applying it. Additionally, only 31.1% indicated they were extremely likely to use SDF upon graduation.Conclusions To reduce the prevalence of caries, dental hygiene graduates must be well-versed with the latest science-based preventive procedures, including non-invasive caries prevention and control therapies. The results of this survey, albeit non representative of the general population of dental hygiene students, suggest a need for a more extensive review of the caries preventive regimen content, especially for silver diamine fluoride, of dental hygiene curricular programs.

In vitro evaluation of wear resistance, microhardness and superficial roughness of different fissure sealants after aging.

The aim of this study was to compare the aging effects on wear, surface roughness and microhardness of fissure sealants having varying contents. Four fissure sealant types were used in the study: Aegis (Bosworth, USA) (Group A), Beautisealant (Shofu, Japan) (Group B), Clinpro (3M, USA) (Group C), and Ultraseal XT/Hydro (Ultradent, USA) (Group U). Hundred disc-shaped specimens (5 mm diameter/3 mm width) were designed according to the manufacturer's instructions and assigned for microhardness/Vickers Hardness (VHN), surface roughness, and wear tests. Thermocycling (10,000 times/5-55 °C ± 2 °C/20 s) and chewing simulator (75,000 times/49 N) were applied as the aging procedures. Measurements were made before and after the aging procedures. The specimens were examined by Scanning Electrone Microscopy (SEM). Data was statistically analyzed through Kruskal Wallis, Wilcoxon and Welch tests. The highest and the lowest changes in mean microhardness values were obtained for Group U (9.88 ± 1.46) and Group A (4.40 ± 0.46), respectively; and a significant difference (p < 0.001) was found between the mean changes in microhardness numbers (U > B > C > A). The median roughness values had no significant difference; the surface roughness had the highest mean differences in Groups U and C (U = C > A > B). Significant difference was found between the mean changes in wear/weight values (p < 0.001); the highest and the lowest mean weight losses were recorded in Group U (0.0097 ± 0.0003 gr), and Group C (0.0041 ± 0.0006 gr), respectively (U > B > A > C). The highest physical changes were determined in Group U after the aging procedures. It is concluded that the aging procedures affect physical structures of all test materials with varying degrees, however Ultraseal XT/Hydro is the most affected. The individual treatment needs and material properties must be considered to select a fissure sealant material.

The effect of the use of the deproteinization agent hypochlorous acid and two different pit and fissure sealant self-adhesive flowable composites upon its bonding with the enamel.

This study evaluates the effect of the deproteinization agents hypochlorous acid and sodium hypochlorite upon the bonding of the two different pit and fissure sealant, self-adhesive flowable composites with the enamel. Thirty-six third molars were randomly divided into six different groups. The groups were formed as follows: Group 1: 37% phosphoric acid + VertiseTM Flow; Group 2: 200 ppm hypochlorous acid + 37% phosphoric acid VertiseTM Flow; Group 3: 5.25% sodium hypochlorite + 37% phosphoric acid + VertiseTM Flow; Group 4: 37% phosphoric acid + Constic; Group 5: 200 ppm hypochlorous acid + 37% phosphoric acid + Constic; Group 6: 5.25% sodium hypochlorite + 37% phosphoric acid + Constic. In each group, samples were obtained that were rectangular prisms in shape (n = 12). Groups to which a deproteinization agent was applied (Groups 2, 3 and 5, 6) showed statistically higher microtensile bonding strength than Group 1, Group 4. There was no statistically significant difference in terms of microtensile bonding strength values between the Groups 3 and the Group 6. The study found that the groups to which deproteinization agents were applied had statistically higher microtensile bonding strength values compared with those groups to which acid and fissure sealants were applied. In this study, it was concluded that the use of fissure-sealing self-adhesive flowable composites after acid application to permanent tooth enamel provides an acceptable bond strength given the limitations of in vitro studies. In line with the results obtained, it was observed that in addition to the removal of the inorganic structure with the application of acid, the removal of the organic structure with the use of deproteinization agent increased the bond strength to the enamel.

The Development and Implementation of a School-Based Dental Sealant Program for Hawaii Public Schools.

BACKGROUND: School-based dental sealant programs are noted to increase sealant uptake among children, especially those from low-income families and those living in rural and underserved areas. However, nationally school-based dental sealant programs are substantially underutilized. This paper describes a partnership approach to a school-based dental sealant program for Title 1 public schools in Hawaii. METHODS: The Hawaii Keiki: Healthy and Ready to Learn program partnered with the Hawaii Dental Service to develop and implement an interprofessional, school-based sealant program (SBSP). This article describes the development of key factors, such as partnerships, an interprofessional team, team roles, policies, and marketing tools to optimize program success. RESULTS: The SBSP has completed over 3 academic years of implementation in Hawaii public schools. In its initial year (school year [SY] 2019-2020), which presented challenges due to the COVID-19 pandemic, it served 6 schools (106 students screened) on 1 island. It expanded to 14 schools on 1 island (193 students screened) in its second year (SY 2020-2021), 28 schools on 3 islands (653 students screened) in its third year (SY 2021-2022), and during the Fall of the fourth year, the program reached 50 schools on 3 islands (1821 students screened) and is projected to reach over 70 schools by the end of SY 2022-2023. CONCLUSION: Taking advantage of strategic partnerships and key interprofessional team members, a school-based dental sealant program can help to improve the oral health of children in public schools by helping to decrease barriers to care.

Effect of sonic oscillation on penetration and marginal adaptation of filled-resin-based fissure sealants.

OBJECTIVES: To evaluate the effect of sonic oscillation on penetration depth and marginal adaptation of resin-based fissure sealants. METHOD AND MATERIALS: Thirty-six extracted human third molars were randomized into three groups: in the HF group, teeth were sealed with a filled-resin-based sealant (Helioseal F); in the Sonic-HF group, teeth were sealed with Helioseal F and subjected to sonic oscillation (Compothixo Device, 140 Hz vibration frequency and ± 150 µm amplitude) before curing; in the CO group, teeth were sealed with an unfilled-resin-based sealant (Clinpro). All teeth were thermocycled for 1,500 cycles at 5°C and 55°C, then sectioned buccolingually into four sections (mesial, two middle, and distal). Sections were evaluated under SEM for marginal adaptation and scored. For penetration depth, three independent measurements from each tooth were recorded under SEM, and data were subjected to statistical analysis. RESULTS: The group subjected to sonic oscillation (Sonic HF) resulted in significantly superior penetration depth and marginal adaptation compared with the HF group, but with no significant difference compared with the CO group. CONCLUSIONS: Sonic activation of resin-based sealant increased penetration depth into fissures and marginal adaptation to the enamel wall without decreasing filler load or compromising sealant mechanical properties.

Wear behavior of different materials used for pit and fissure sealing.

PURPOSE: To evaluate the wear of different materials used for pit and fissure sealing applied with non-invasive and invasive preparation techniques. METHODS: A total of 170 molar teeth were divided into two main preparation groups (non-invasive and invasive), each consisting of eight subgroups after a control group was separated for wear standardization. Eight subgroups included: nano-filled flowable composite (Filtek Ultimate Flow), nanohybrid flowable composite (GrandioSo Flow), micro-hybrid flowable composite (Majesty Flow), resin-based unfilled fissure sealant (ClinPro Sealant), resin-based filled fissure sealant (Fissurit FX), resin-based highly filled fissure sealant (GrandioSeal), giomer-based fissure sealant (BeautiSealant), and glass-ionomer-based fissure sealant (Fuji Triage) (n= 10). The materials were applied according to the manufacturers' instructions. The initial data were obtained for wear analysis. The specimens were subjected to 2-year thermocycling and brushing simulations. Final data were obtained, and the wear characteristics were evaluated digitally. Data were statistically analyzed (P< 0.05). RESULTS: There were no significant differences in wear between the non-invasive and invasive application groups (P< 0.05). In comparison of the materials, flowable composites presented the lowest wear (0.15 P± 0.13), and glass-ionomer-based fissure sealant presented the highest wear (0.66 P± 0.32). CLINICAL SIGNIFICANCE: The present study reported that the invasive preparation technique, which slightly abrades the enamel surfaces, did not adversely affect the wear of the sealant materials. Although the application of flowable composites as fissure sealants with a bonding agent is time-consuming and costly, it yielded better results in terms of wear.

A System Dynamics Model of Caries Preventive Interventions in Thailand's School-Aged Population.

PURPOSE: To compare the long-term effects of the Ministry of Public Health's (MOPH) caries preventive interventions for 6- to 12-year-olds (supervised toothbrushing [STB], dental sealant, and combined STB+sealant) to the base case (no intervention) using the System Dynamics Model. MATERIALS AND METHODS: The System Dynamics Model was used to evaluate the intervention scenarios of supervised toothbrushing (STB), sealant, and combined STB+sealant with the base-case scenario. The effectiveness data for the model's interventions were obtained from systematic reviews and meta-analyses. RESULTS: The model determined that the caries-free population increased by 36.2%, 25.5%, and 14.5%, while the caries-affected population decreased by 8.1%, 5.5%, and 3.1% in the combined STB+sealant, sealant, and supervised toothbrushing scenarios compared to the base case at 15 years of age. CONCLUSION: Combined STB+sealant is the most efficacious intervention among those administered to children between the ages of 6 and 12 with permanent teeth. In addition, the System Dynamics Model could be helpful in comparing interventions or policies to determine the optimal intervention for a given population.

Evaluation of the effect of high-intensity light-curing device on micro-leakage of pits and fissure sealants.

Reducing treatment time is one of the most important trends in modern dentistry. This study aimed to compare the micro-leakage around the resin sealants when using both high and conventional intensity light-curing systems. The study sample consisted of 30 extracted human maxillary premolar teeth that were divided into two equal groups according to the light-curing system used: Group 1, High-Intensity Light-Curing System and Group 2, Conventional Light-Curing System. Light-curing by Woodpecker I-LED device with two intensities (high and conventional) has been used. All teeth were subjected to 500 cycles of thermocycling. Then, a methylene blue dye microleakage test was performed, and the teeth were sectioned longitudinally and studied under a stereo microscope. The mean of micro-leakage in the high-intensity group (1.33 ± 1.29) was less than in the conventional intensity group (1.63 ± 1.29) without any statistically significant differences (p = 0.320). The high-intensity light-curing system mode may be a good and acceptable alternative to conventional intensity light-curing system mode in polymerization of pits and fissure sealants.

Evaluating the effect of three fissure preparation techniques on microleakage of a colored flowable composite used as a fissure sealant.

Pit and fissure sealants play an essential role in preventive dentistry. This study evaluates the microleakage levels of a new and colored flowable composite applied as a sealant after three preparation techniques. A total of 24 non-carious mandibular permanent molars with deep pits and fissures were included in the study. Pit and fissures were prepared with 37% phosphoric acid, tungsten carbide bur and fissurotomy burs (SS WHITE Dental, New Jersey, USA) using conventional, enameloplasty and fissurotomy techniques. All samples were thermocycled following the placement of Rainbow Flow (PPH CERKAMED Wojciech Pawlowski, Poland) as a sealant and sections were taken after immersion in methylene blue dye. The microleakage levels of the samples were examined under a stereomicroscope (Olympus SZX-7 Olympus SZ-61 Stereo Microscope) at 2.8× magnification to analyze the dye penetration of the flowable composite. The 144 sections were examined and scoring for microleakage was done by examining the dye penetration from the occlusal border to the base of the fissure. Considering all sections regardless of the preparation technique, it was found that 16.6% of the sections have no leakage. Regarding the microleakage scores, the mean score of the conventional group was 1.87 ± 0.98, the mean score of the enameloplasty group was 1.88 ± 1.14, and the mean score of the fissurotomy group was 1.81 ± 1.1. The median scores of the conventional, enameloplasty and fissurotomy groups were 2, 2 and 1.5, respectively. The present study reports no difference between the microleakage level of a colored flowable composite material used as a pit and fissure sealant following three fissure preparation techniques and supports the clinical use of this material.

Evaluation of flexural strength, degree of conversion, and demineralization-prevention properties in adjacent tooth structures of an experimental fissure sealant containing nano-calcium-phosphate compounds.

BACKGROUND: The present study aimed to evaluate the flexural strength, degree of conversion, and demineralization-prevention ability of an experimental fissure sealant containing nano-calcium-phosphate compounds. METHODS: An experimental sealant was formulated using silica and nano hydroxyapatite filler particles. The control group consisted of the DENU Seal (n = 10, each group). The flexural bond strength was evaluated by UTM. DC was evaluated by FTIR. To evaluate the demineralization-prevention ability, Cl V cavities in 10 third molar teeth restored with two sealant products, followed by an acid challenge then the Vickers microhardness test was carried out. RESULTS: The mean flexural strength in the commercial group was higher than the experimental group. However, the mean flexural modulus was not significantly different between the two groups. In the experimental group, DC was significantly higher than the commercial group. Adjacent to the interface, the decrease in microhardness in the experimental group was significantly less than the commercial group. However, on the tooth surface, there were no significant differences between the two groups. In the experimental group, the decrease in microhardness at the interface was less than at the tooth surface, however the situation was opposite in the commercial group. CONCLUSIONS: Incorporating hydroxyapatite into the sealant structure might prevent demineralization, without adverse effects on flexural modulus and degree of conversion.