Environmental noise pollution and its association with temporomandibular joint disorders, malocclusion, and bruxism: A Comparative cross-sectional study of adults in high-traffic and low- traffic areas

Background Chronic environmental noise exposure is a recognized public health concern linked to stress-mediated physiological responses, yet its specific impact on temporomandibular disorders (TMD), bruxism, and malocclusion remains poorly investigated. Objectives To compare the prevalence of TMD, malocclusion, and bruxism between adults residing in high-traffic versus Low- traffic areas in New Delhi, India, and to identify independent predictors of TMD risk. Methods This comparative cross-sectional study enrolled 300 adults (150 per group) from high traffic and low traffic residential areas of New Delhi, India. Individual-level noise exposure (LAeq,24h) was objectively measured. TMD was diagnosed using Diagnostic Criteria for Temporomandibular Disorders (DC/TMD Axis I criteria). Bruxism, malocclusion, perceived stress scale −1= (PSS-10), and Pittsburgh sleep quality (PSQI) were assessed using validated instruments. Multivariable logistic regression and mediation analysis were performed. Results High-traffic residents had significantly higher TMD prevalence (61.3% vs. 25.3%), bruxism (42.7% vs. 14.0%), and malocclusion (52.0% vs. 26.0%; all p < 0.001). A significant dose-response relationship was confirmed (χ² for trend p < 0.001). High noise exposure was the strongest independent predictor of TMD (aOR = 3.10; 95% CI: 2.00–4.80). Bruxism and perceived stress accounted for 41.4% of this association in exploratory mediation analysis, a pattern compatible with mediation, though the cross sectional design precludes establishing temporal precedence. Conclusions Environmental noise exposure was independently and dose-dependently associated with TMD andbruxism. malocclusion was also prevalent in high traffic areas; however, this cross sectional association more likely reflects pre-existing skeletal or occlusal characteristics than a causal effect of noise, and should be interpreted with caution. These findings support noise abatement policies and targeted oral health screening in high traffic urban environments.