Diagnostic Strategies for Restorations Management: A 70-Month RCT.

We aimed to evaluate the impact of 2 visual diagnostic strategies for assessing secondary caries and managing permanent posterior restorations on long-term survival. We conducted a diagnostic cluster-randomized clinical trial with 2 parallel groups using different diagnostic strategies: (C+AS) based on caries assessment, marginal adaptation, and marginal staining aspects of the FDI (World Dental Federation) criteria and (C) based on caries assessment using the Caries Associated with Restorations or Sealants (CARS) criteria described by the International Caries Detection and Assessment System (ICDAS). The treatment for the restoration was conducted based on the decision made following the allocated diagnostic strategy. The restorations were then clinically reevaluated for up to 71 mo. The primary outcome was restoration failure (including tooth-level failure: pain, endodontic treatment, and extraction). Cox regression analyses with shared frailty were conducted in the intention-to-treat population, and hazard ratios (HRs) and 95% confidence intervals (95% CIs) were derived. We included 727 restorations from 185 participants and reassessed 502 (69.1%) restorations during follow-up. The evaluations occurred between 6 and 71 mo. At baseline, C led to almost 4 times fewer interventions compared with the C+AS strategy. A total of 371 restorations were assessed in the C group, from which 31 (8.4%) were repaired or replaced. In contrast, the C+AS group had 356 restorations assessed, from which 113 (31.7%) were repaired or replaced. During follow-up, 34 (9.2%) failures were detected in the restorations allocated to the C group and 30 (8.4%) allocated to the C+AS group in the intention-to-treat population, with no significant difference between the groups (HR = 0.83; 95% CI = 0.51 to 1.38; P = 0.435, C+AS as reference). In conclusion, a diagnostic strategy focusing on marginal defects results in more initial interventions but does not improve longevity over the caries-focused strategy, suggesting the need for more conservative approaches.

Challenges in conducting clinical research in primary care dentistry.

The integration of dentistry into primary health care is crucial for promoting patient well-being. However, clinical studies in dentistry face challenges, including issues with study design, transparency, and relevance to primary care. Clinical trials in dentistry often focus on specific issues with strict eligibility criteria, limiting the generalizability of findings. Randomized clinical trials (RCTs) face challenges in reflecting real-world conditions and using clinically relevant outcomes. The need for more pragmatic approaches and the inclusion of clinically relevant outcomes (CROs) is discussed, such as tooth loss or implant success. Solutions proposed include well-controlled observational studies, optimized data collection tools, and the integration of artificial intelligence (AI) for predictive modelling, computer-aided diagnostics and automated diagnosis. In this position paper advocates for more efficient trials with a focus on patient-centred outcomes, as well as the adoption of pragmatic study designs reflecting real-world conditions. Collaborative research networks, increased funding, enhanced data retrieval, and open science practices are also recommended. Technology, including intraoral scanners and AI, is highlighted for improving efficiency in dental research. AI is seen as a key tool for participant recruitment, predictive modelling, and outcome evaluation. However, ethical considerations and ongoing validation are emphasized to ensure the reliability and trustworthiness of AI-driven solutions in dental research. In conclusion, the efficient conduct of clinical research in primary care dentistry requires a comprehensive approach, including changes in study design, data collection, and analytical methods. The integration of AI is seen as pivotal in achieving these objectives in a meaningful and efficient way.

NaOCl Application after Acid Etching and Retention of Cervical Restorations: A 3-Year Randomized Clinical Trial.

This study evaluated the retention of composite resin restorations in noncarious cervical lesions (NCCLs) performed with or without pretreatment with 10% NaOCl solution (deproteinization). A randomized, controlled, split-mouth, double-blinded trial was carried out. Thirty patients with at least two NCCLs were included in the study. The NCCLs were randomly allocated into two treatment groups: control (acid etching with 37% phosphoric acid + placebo solution + Adper Single Bond 2/3M Oral Care + Filtek Z350/3M Oral Care) or experimental group (acid etching with 37% phosphoric acid + 10% NaOCl solution + Adper Single Bond 2 + Filtek Z350). A calibrated examiner evaluated the restorations at baseline (1 week) and recalls (6, 12, 24, and 36 months) using the FDI criteria. The primary outcome evaluated was retention of the restorations. Data were analyzed by the Kaplan-Meier method and the log-rank test (α=0.05). After 3 years, 64 restorations were evaluated in 23 patients. The annual failure rate was 9% for the control group and 17.8% for the experimental group (deproteinization technique). Considering the failures and their distribution among the characteristics of the patients and NCCLs, no statistically significant differences were observed for the control and experimental treatment groups (p=0.077) or the number of teeth in the mouth (p=0.320). Restorations in the mandible (p=0.039) and premolars (p=0.013) showed significantly lower clinical survival rates. The deproteinization pretreatment with a 10% NaOCl solution did not promote additional retention of restorations in NCCLs. (clinicaltrials. gov: NCT03086720).

Trajectories of Sugar Consumption and Dental Caries in Early Childhood.

This study verifies the association between the trajectory of sugar consumption and dental caries in the 2015 Pelotas Birth Cohort in Pelotas, Brazil. It was conducted with data from the follow-ups at 3, 12, 24, and 48 mo from the 2015 Birth Cohort, which included 4,275 children born alive in hospitals in Pelotas. Data collection included standardized questionnaires for first caregivers applied by trained interviewers at all follow-ups. Exposure was the trajectory of sugar consumption from 3 to 48 mo (always low, always intermediate, increasing, and always high), obtained by group-based trajectory modeling. The outcome of this study was dental caries, obtained through clinical examination performed by calibrated dentists at 48 mo of age. Socioeconomic conditions and oral health instruction from a health professional during the first 4 y of life were included in the analysis as potential confounders. Prevalence ratios and their 95% confidence intervals were provided from generalized estimating equations with a log-Poisson with robust variance specification. In total, 3,654 (91.1%) children participated in the survey at 48 mo, and 2,806 children had complete data for the analyzes performed. Of these, 1,012 (36.1%; 95% confidence interval [CI], 34.3-37.8) experienced caries, and 723 (25.8%; 95% CI, 24.2-27.4) had cavitated caries. Regarding cavitated caries, the prevalence was 1.48 times higher in the group with increasing sugar consumption than children with always low consumption. There is an association between the trajectory of sugar consumption and dental caries at 48 mo. Children with increasing and always high sugar consumption have the highest prevalence of caries.

The Effect of a Charcoal-based Powder for Enamel Dental Bleaching.

CLINICAL RELEVANCE: Charcoal based-powders are not effective for dental bleaching. SUMMARY: Charcoal-based dentifrices for dental whitening are a novelty in the market. Manufacturers claim that such charcoal-based products have whitening, remineralization, antimicrobial, and antifungal properties of charcoal in such products. However, there is no substantial scientific evidence for these claims. This laboratory randomized study was designed to evaluate the whitening properties of a charcoal-based toothpowder. A total of 45 bovine dental enamel discs were randomly distributed into three groups (n=15): group 1, mechanical brushing with a 1450-ppm F toothpaste (control group); group 2, mechanical brushing with an activated charcoal-based powder; group 3, bleaching per the standard protocol using 10% carbamide peroxide. The surface roughness and color of each specimen were analyzed at baseline and after 14 days of experiment. The surface of one randomly selected specimen from each group was examined using a scanning electron microscope (SEM). The Kruskal-Wallis test was used to compare groups at a significance level of 5%. Only group 3 promoted a statistically significant effect on ΔE compared with groups 1 and 2 (p<0.001 and p=0.003, respectively). No statistically significant difference was found between groups for surface roughness (p>0.05). SEM revealed a more irregular surface in group 1 specimens compared with group 2 and 3 specimens. The charcoal-based powder did not seem to have any bleaching effect.

Occlusal and Esthetic Enhancement: A Noninvasive Approach to an Old Dilemma.

This article describes an indirect composite restoration technique for diastema closure and tooth lengthening with a noninvasive approach using regularly available materials such as silicone, composite resin, and an adhesive system. The procedure resulted in occlusal and functional improvement, with diastema closure, protrusive guide adjustment, and an increase in central incisor length. The procedure provided an adequate proportion of the central incisors with an esthetically natural appearance. It also resulted in simple, fast, and accurate manufacturing with a noninvasive esthetic indirect rehabilitation compared with more invasive preparation of ceramic veneers.

A threshold gap size for in situ secondary caries lesion development.

OBJECTIVES: This study investigated the influence of very small gaps in secondary caries (SC) development and additionally linked the threshold gap size with the caries activity level from volunteers. METHODS: For 21 days, 15 volunteers wore a modified occlusal splint loaded with dentin-composite samples restored with different interfaces: bonded (B = samples restored with complete adhesive procedure), no-bonded (NB = restored with composite resin without adhesive procedure), and 30, 60 and 90 µm (no adhesive procedure and with intentional gap). The splint was dipped in a 20% sucrose solution (10 min) 8 x per day. Samples were imaged with transversal wavelength independent microradiography (T-WIM) and lesion depth and mineral loss were calculated. Average wall lesion depth from each volunteer was determined and according to the values the volunteers were grouped as high, mid and low caries activity levels. RESULTS: No wall lesion formation was observed in B and NB groups. In general, intentional gaps led to SC lesion depth progression independent of caries activity level of volunteers. No substantial wall lesions were found for two volunteers. A trend for deeper lesion in larger gaps was observed for the high activity group. CONCLUSION: Very small gaps around or wider than 30 µm develop SC independent of the caries activity level of the patient and SC wall lesion progression seemed to be related to individual factors even in this standardized in situ model. SIGNIFICANCE: Independently of caries activity level of the patient, the threshold gap size for secondary caries wall lesion seems to be 30 µm at most.

A Multicenter Randomized Double-blind Controlled Clinical Trial of Fiber Post Cementation Strategies.

OBJECTIVES: The aim of this prospective randomized multicenter clinical trial was to evaluate the survival rate of glass fiber-reinforced posts cemented with self-adhesive or regular resin cements. METHODS: The sample was comprised of 152 teeth randomized within two centers and in accordance with the adhesive strategies for RelyX U100/U200 (3M ESPE) or Single Bond and RelyX ARC (3M ESPE). The cementation procedures were standardized and performed by previously trained operators. The primary outcome evaluated was post debonding. A trained evaluator, one for each center, assessed all subjects at intervals of 12 months for up to 6 years. Statistical analysis was performed using the Kaplan-Meier method. RESULTS: There was no statistically significant difference in survival rates between the two strategies assessed ( p=0.991), with a 92.7% survival rate for the self-adhesive cement and 93.8% for the regular cement. CONCLUSION: Both the self-adhesive and the regular resin cements are good alternatives for glass fiber post cementation.

Secondary caries development and the role of a matrix metalloproteinase inhibitor: A clinical in situ study.

OBJECTIVES: This in situ study aimed to investigate whether the dentin treatment with MMPs inhibitor (CHX 2%) could influence the development of secondary caries wall lesions in different dentin-composite interfaces. MATERIAL AND METHODS: For 21 days, 15 volunteers wore a modified-occlusal splint loaded with dentin-composite samples treated or not with CHX and restored according 4 different interface conditions: Bonding (B = samples restored with complete adhesive procedure), no bonding (NB = restored with composite resin without adhesive procedure), 100 µm (no adhesive procedure and with intentional gap) and 100 µm + B (adhesive material on composite side and intentional gap). Eight times per day, the splint with samples was dipped in a 20% sucrose solution for 10 min. Before and after caries development, samples were imaged with T-WIM and lesion depth (LD) and mineral loss (ML) were calculated. RESULTS: Linear mixed effect analysis showed that dentin treatment with CHX did not significantly affect the caries lesion progression (LD and ML; p ≤ 0.797). Dentin wall lesions were observed in the 100 µm and 100 µm + B groups independently of MMP inhibitor treatment. CONCLUSION: The treatment of dentin with MMP inhibitor was not able to slow down the secondary caries wall lesion development in this in situ study. SIGNIFICANCE: The dentin treatment with 2% CHX did not prevent secondary caries wall lesion initiation.

Clinical studies in restorative dentistry: New directions and new demands.

Clinical research of restorative materials is confounded by problems of study designs, length of trials, type of information collected, and costs for trials, despite increasing numbers and considerable development of trials during the past 50 years. This opinion paper aims to discuss advantages and disadvantages of different study designs and outcomes for evaluating survival of dental restorations and to make recommendations for future study designs. Advantages and disadvantages of randomized trials, prospective and retrospective longitudinal studies, practice-based, pragmatic and cohort studies are addressed and discussed. The recommendations of the paper are that clinical trials should have rational control groups, include confounders such as patient risk factors in the data and analysis and should use outcome parameters relevant for profession and patients.

In vitro biofilm models to study dental caries: a systematic review.

The aim of this systematic review is to characterize and discuss key methodological aspects of in vitro biofilm models for caries-related research and to verify the reproducibility and dose-response of models considering the response to anti-caries and/or antimicrobial substances. Inclusion criteria were divided into Part I (PI): an in vitro biofilm model that produces a cariogenic biofilm and/or caries-like lesions and allows pH fluctuations; and Part II (PII): models showing an effect of anti-caries and/or antimicrobial substances. Within PI, 72.9% consisted of dynamic biofilm models, while 27.1% consisted of batch models. Within PII, 75.5% corresponded to dynamic models, whereas 24.5% corresponded to batch models. Respectively, 20.4 and 14.3% of the studies reported dose-response validations and reproducibility, and 32.7% were classified as having a high risk of bias. Several in vitro biofilm models are available for caries-related research; however, most models lack validation by dose-response and reproducibility experiments for each proposed protocol.

Restoration Survival: Revisiting Patients' Risk Factors Through a Systematic Literature Review.

A literature review was conducted to investigate the influence of patient-related factors on restoration survival in posterior permanent teeth as well as to report the methods used to collect these factors. The selection of articles on longitudinal clinical studies investigating the survival of posterior restorations (except full crowns and temporary fillings) and including patient-related factors was performed by applying predefined criteria. The review was organized into two parts, the first describing how patient factors were assessed in the studies (n=45) and the second presenting the statistical significance (n=27) and size of the effect (n=11) of these factors on restoration survival. Patient-related factors mentioned in the studies included age; gender; caries risk; caries activity/severity; decayed, missing, filled teeth; number of restorations; oral hygiene; and bruxism, among others. Sixteen studies included the patient age or age range in the analysis, which was found to be significant in 47% of the studies. Regarding gender, four of 17 reports found a significant effect on survival, showing more failures for men in three studies. The caries risk profile or related variables were included in the analysis of 15 studies, and a significant effect on survival was reported for high-caries-risk individuals (or related variables) in 67% of these studies. Bruxism was also found to influence restoration survival in three of six studies where this variable was investigated. Some issues were found regarding the reporting of methods used to classify patients according to risk and were thoroughly discussed. In view of the information gathered in this review, the assessment of patient factors along with other variables should become part of clinical studies investigating restoration survival, since several of these factors were shown to influence the failure of restorations, regardless of the material type.

An in vitro dynamic microcosm biofilm model for caries lesion development and antimicrobial dose-response studies.

Some dynamic biofilm models for dental caries development are limited as they require multiple experiments and do not allow independent biofilm growth units, making them expensive and time-consuming. This study aimed to develop and test an in vitro dynamic microcosm biofilm model for caries lesion development and for dose-response to chlorhexidine. Microcosm biofilms were grown under two different protocols from saliva on bovine enamel discs for up to 21 days. The study outcomes were as follows: the percentage of enamel surface hardness change, integrated hardness loss, and the CFU counts from the biofilms formed. The measured outcomes, mineral loss and CFU counts showed dose-response effects as a result of the treatment with chlorhexidine. Overall, the findings suggest that biofilm growth for seven days with 0.06 ml min(-1) salivary flow under exposure to 5% sucrose (3 × daily, 0.25 ml min(-1), 6 min) was suitable as a pre-clinical model for enamel demineralization and antimicrobial studies.

Can Silanization Increase the Retention of Glass-fiber posts? A Systematic Review and Meta-analysis of In Vitro Studies.

The role of silanes in the bonding of resin luting agents to glass-fiber posts (GFPs) is a controversial topic, and the question still remains whether post silanization is able to improve the retention of GFPs luted into root canals. Thus, this study was designed to determine whether evidence exists to justify silanization of GFPs before cementation to increase their retention into root canals. In vitro studies that evaluated the retention of GFPs cemented into root canals or artificial substrates and that used silane coupling agents for pretreatment of the post were selected. Searches were carried out in PubMed and Scopus databases with no publication year or language limits. The last search was carried out in August 2014. Two distinct data analyses were carried out: 1) control group (no post pretreatment) vs silane only and 2) post pretreatment + silane vs silane only. Pooled-effect estimates were obtained by comparing the difference between each bond strength mean value and were expressed as the weighted mean difference between groups (p≤0.05). A total of 178 articles were found, and 23 were included in the review. The results were affected by the substrate into which the GFPs were luted (teeth or artificial devices). The analysis between control group and silane only for studies that used artificial devices favored the use of silane (p<0.0001), but considering studies that used teeth as substrate, no significant difference was observed (p=0.35). The analysis between silane only and pretreatment + silane did not show a significant difference between groups when artificial devices were used (p=0.71), whereas the analysis favored the use of post pretreatment + silane over silane (p<0.00001) only when the GFPs were luted into teeth. In conclusion, this review indicates that silanization improves the retention of GFPs luted into root canals provided that selective surface pretreatments are applied to the post before silanization.

Maternal attitudes towards tooth decay in children aged 12-18 months in Pelotas, Brazil.

AIM: This was to assess mothers' attitudes towards dental caries in children aged 12-18 months. METHODS: This study targeted mothers of children aged 12-18 months. Data about demographic and socioeconomic status were collected by interviews with each mother. In addition, the mother was asked about her attitudes regarding caries in her child's primary teeth. A dental examination of each child was also conducted. Chi-square, bivariate, and multiple logistic regression analyses were performed. RESULTS: A total of 262 mother-child pairs were included, and 18.7 % of the children had dental caries. If a child presented with dental caries in their primary teeth, 93.5 % of the mothers reported that they would take the child to a dentist. Mothers who had only one child and those who had children with dental caries were more likely to report that they did not expect primary dental caries treatment by the dentist. CONCLUSION: Most mothers reported that they would take their children to a dentist when they presented with dental caries. Despite this positive result, educational measures should continue to be emphasised, especially among mothers of children at a higher risk of caries and among first-time mothers.

Contamination of Composite Resin by Glove Powder and Saliva Contaminants: Impact on Mechanical Properties and Incremental Layer Debonding.

This study investigated the influence of digital manipulation of a composite resin (Z250; 3M ESPE, St Paul, MN, USA) with gloves contaminated with powder and/or human stimulated saliva on the mechanical properties and incremental layer debonding of the restorative. The six groups tested were powdered gloves with or without saliva, powder-free gloves with or without saliva, powdered gloves with saliva cleaned with 70% ethanol, and no digital manipulation or contamination (control). Diametral tensile strength, flexural strength, flexural modulus, and incremental layer shear bond strength were evaluated. Each composite increment was digitally manipulated for 10 seconds. Data from each test were separately analyzed using analysis of variance and the Student-Newman-Keuls test (α=0.05). No significant differences for diametral tensile strength were observed. Manipulation of the composite using powder-free gloves with saliva or using gloves cleaned with ethanol generated higher flexural strength and modulus compared to the other groups. The control group and the group manipulated using powdered gloves with saliva generally showed lower mechanical performances. Lower incremental layer bond strength was observed for the group manipulated with powdered gloves without saliva. The control group and the groups manipulated with powdered gloves with saliva or cleaned with ethanol showed higher shear bond strengths. Most of the failures were cohesive. In conclusion, digital manipulation might be important for the composite resin to achieve better mechanical performance and incremental layer bond strength, provided that the gloves are not contaminated. Cleaning the gloves with ethanol might avoid the negative effects of digital manipulation using contaminated gloves.

Bonding of Adhesive Luting Agents to Caries-affected Dentin Induced by a Microcosm Biofilm Model.

OBJECTIVES: To evaluate the bond strength of adhesive luting agents applied to caries-affected dentin (CAD). METHODS: Thirty-six noncarious human third molars were abraded to expose an occlusal dentin surface. Caries lesions were induced in half of the samples using a microcosm biofilm model. Biofilm was cultivated under an anaerobic atmosphere for 14 days in a medium enriched with mucin. The same medium containing 1% sucrose was alternated for 4 hours per day. Cylinders of resin cement (RelyX ARC, RelyX U200, or BisCem) were built up over the dentin substrate and submitted to shear bond load. The samples were then longitudinally sectioned. The hardness and elastic modulus of dentin were measured at different depths from the occlusal surface. A three-dimensional finite element simulation was performed to analyze the residual stress distribution during the shear bond strength test. Bond strength data were analyzed by two-way analysis of variance (ANOVA) and hardness and elastic modulus by split-plot ANOVA. Multiple comparisons were performed with the SNK test (α=0.05). RESULTS: For all cements, the highest bond strengths were observed in sound dentin. Relyx ARC bond strength was similar to that of RelyX U200 for both substrates; BisCem had the lowest values. CAD had lower hardness (above a depth of 100 µm) and elastic modulus (above a depth of 150 µm) values than sound dentin. Stress distribution during the bond strength test was similar under all experimental conditions. CONCLUSION: Impairment of the mechanical properties of dentin promoted by carious lesions reduced the bond strength of adhesive luting agents.

Restoration materials and secondary caries using an in vitro biofilm model.

This in vitro study investigated whether restoration materials and adhesives influence secondary caries formation in gaps using a short-term in vitro biofilm model. Sixty enamel-dentin blocks were restored with 6 different restoration materials with or without adhesives (n = 10 per group) with a gap: 1) Clearfil AP-X composite, 2) Clearfil AP-X composite + SE Bond, 3) Clearfil AP-X composite + ProtectBond, 4) Filtek Silorane composite, 5) Filtek Silorane composite + Silorane System adhesive, or 6) Tytin amalgam. Specimens were subjected to an intermittent 1% sucrose biofilm model for 20 days to create artificial caries lesions. Lesion progression in the enamel-dentin next to the different materials was measured in lesion depth (LD) and mineral loss (ML) using transversal wavelength independent microradiography (T-WIM). A regression analysis was used to compare the LD and ML of the different restoration materials at 4 measurement locations: 1 location at the surface of the enamel, 1 location at the wall of the enamel, and 2 locations at the wall of the dentin. A statistically significant effect of AP-X composite with Protect Bond was found for LD and ML at the WallDentin1 location, leading to less advanced wall lesions. An additional finding was that gap size was also statistically significant at the 2 wall locations in dentin, leading to increasing lesion progression with wider gaps. In conclusion, adhesives can influence wall lesion development in gaps. Protect Bond showed significantly less caries progression compared to bare restoration materials or other adhesives in this short-term in vitro biofilm model.

Correlation between the cariogenic response in biofilms generated from saliva of mother/child pairs.

This study aimed to correlate the cariogenic responsiveness of biofilms generated from the saliva of mothers and children. The mother-child pairs were classified according to the children's caries levels: caries-free, early childhood caries (ECC) or severe ECC. Microcosm biofilms were grown on enamel discs for 10 days. Factors under evaluation were caries experience levels, inoculum source (mothers and children) and growth conditions including cariogenic challenge (growth medium provided with and without sucrose) and no cariogenic challenge (growth medium sucrose-free). Statistical analysis was performed with ANOVA and Tukey's test, and the Spearman correlation test. Regular sucrose exposure resulted in a higher surface hardness change (%SHC). The correlation between biofilms formed from saliva of mother-child pairs was significant regarding pH, total aciduric microorganisms and lactobacilli counts under cariogenic challenge. Biofilm growth originating from mother-child pairs under regular sucrose exposure promoted the same cariogenic response independently of caries experience and the microbiological profile of the donors.

Longevity of posterior composite restorations: a systematic review and meta-analysis.

The aim of this meta-analysis, based on individual participant data from several studies, was to investigate the influence of patient-, materials-, and tooth-related variables on the survival of posterior resin composite restorations. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a search resulting in 12 longitudinal studies of direct posterior resin composite restorations with at least 5 years' follow-up. Original datasets were still available, including placement/failure/censoring of restorations, restored surfaces, materials used, reasons for clinical failure, and caries-risk status. A database including all restorations was constructed, and a multivariate Cox regression method was used to analyze variables of interest [patient (age; gender; caries-risk status), jaw (upper; lower), number of restored surfaces, resin composite and adhesive materials, and use of glass-ionomer cement as base/liner (present or absent)]. The hazard ratios with respective 95% confidence intervals were determined, and annual failure rates were calculated for subgroups. Of all restorations, 2,816 (2,585 Class II and 231 Class I) were included in the analysis, of which 569 failed during the observation period. Main reasons for failure were caries and fracture. The regression analyses showed a significantly higher risk of failure for restorations in high-caries-risk individuals and those with a higher number of restored surfaces.