Association Between Occlusal Interferences, Temporomandibular Joint Dysfunction, and Bruxism in Romanian Adults

Background: Bruxism is a common parafunctional activity involving repetitive jaw muscle movements during wakefulness (awake bruxism) or sleep (sleep bruxism). While its multifactorial etiology is widely accepted, the roles of occlusal interferences, temporomandibular joint (TMJ) dysfunction, stress, and sleep-related breathing disturbances remain under investigation. Objectives: This cross-sectional study evaluated associations between bruxism and occlusal discrepancies, TMJ symptoms, stress, and sleep-related variables (snoring and obstructive sleep apnea, OSA) in Romanian adults. Methods: Ninety-eight adults (mean age: 30.4 ± 8.9 years) completed a structured questionnaire reviewed for content validity and pilot-tested for clarity but not formally validated. Participants were categorized into bruxism (n = 51) and control (n = 47) groups. Variables assessed included bruxism type, TMJ symptoms, occlusal interferences, stress, snoring, OSA, and parafunctional habits. Bivariate and multivariate logistic regression analyses were conducted. Results: Sleep bruxism was predominant (88%), with 59% classified as sleep-only bruxers. Occlusal discrepancies (46% vs. 14%, p < 0.001), TMJ symptoms (joint pain: 38% vs. 8%; fatigue: 44% vs. 10%), and habitual snoring (60% vs. 22%, p < 0.001) were significantly more common among bruxers. No significant difference was observed in OSA prevalence. Independent predictors of bruxism included occlusal interferences (adjusted OR = 4.7, p = 0.009), TMJ symptoms (adjusted OR = 6.5, p = 0.002), and habitual snoring (adjusted OR = 4.1, p = 0.016). Conclusions: Bruxism was significantly associated with occlusal interferences, TMJ dysfunction, and habitual snoring, supporting the need for multifactorial assessment and integrated clinical management. Limitations: This study relied on self-reported bruxism classification and a non-validated questionnaire instrument, which may limit generalizability and diagnostic accuracy.