Impact of moderate to heavy occlusal forces and tooth wear on interproximal caries prevalence in posterior teeth.

This cross sectional analytical study evaluated whether clinical indicators of occlusal forces are associated with the prevalence of interproximal caries in posterior teeth. A total of 403 posterior teeth from 109 patients (12-70 years) attending Mashhad Dental School were examined. Dental facets, non carious cervical lesions, occlusion type, and contact position were recorded as clinical indicators of occlusal forces, and interproximal caries was assessed clinically and radiographically using ICDAS II criteria. Caries risk status was determined using the CAMBRA system. The association between dental facets and interproximal caries was analyzed using bivariate and multivariable logistic regression, and multilevel logistic regression with teeth nested within subjects to account for clustering. Models were adjusted for gender, plaque presence, occlusion type, and contact position. Dental facets were present in 72.5% of examined teeth, and interproximal caries in 32.5%. Teeth with facets showed a higher prevalence of interproximal caries than teeth without facets (38.7% vs. 16.2%). The presence of facets was strongly associated with interproximal caries in both standard and multilevel models (adjusted odds ratio approximately 3.0; 95% confidence interval roughly 1.7-5.6; p < 0.001). This association persisted across subgroups defined by plaque presence and occlusion type, whereas plaque, occlusion type, contact position, and gender were not independently associated with caries. Teeth with facets were also found in patients with a greater number of extracted teeth. Within the limitations of this cross sectional study, clinical indicators of increased occlusal forces, particularly dental facets, were significantly associated with a higher prevalence of interproximal caries in posterior teeth. These findings support the hypothesis that biomechanical factors may contribute to the development of interproximal caries in addition to traditional biological and behavioral risk factors, but they do not establish a causal relationship. Assessment of occlusal indicators such as wear facets may help identify patients at increased risk of interproximal caries and could be incorporated into caries risk evaluation and preventive planning.