Awake bruxism in TMD patients referred to tertiary care: a retrospective study on its assessment and TMD management

Background: Bruxism is defined as a repetitive jaw-muscle activity characterized by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. Bruxism can occur during sleep (sleep bruxism, SB) or during wakefulness (awake bruxism, AB). To date, the effect of AB on the purported negative consequences of bruxism has remained unclear. Objectives: The assessment of AB, its relation to TMD treatment modalities, and their possible outcome were investigated among TMD patients resistant to treatment in primary care and referred to a tertiary care clinic. Methods: The records of 115 patients were studied. Patients were referred to the Head and Neck Center, Department of Oral and Maxillofacial Diseases, Helsinki University Central Hospital, for TMD treatment between 2017 and 2020. The data derived from the eligible patients' records included the following: background data (age, sex), referral data (reason, previous treatment), medical background (somatic and psychiatric), clinical and possible radiological diagnoses at a tertiary care clinic, treatment modalities for masticatory muscle myalgia, bruxism assessment, its possible treatment modalities and their outcome, and overall management outcome. We analyzed the outcomes of single treatment modalities and combined groups of modalities. For the demographic data, the Chi square test and Fischer's Exact test were used to determine the associations between the categorical variables. A Sankey-diagram was used to describe the flow of treatment. Results: Temporomandibular joint-pain-dysfunction syndrome (K07.60) was the most frequent single reason to refer a patient to tertiary care (17.4%). At referral, men had myalgia (M79.1) significantly more often (p=0.034) than women. Similarly, men had depression (p=0.002) more often and other psychiatric diagnoses (p=0.034). At tertiary care, the presence of AB was assessed in 53.9%, and self-reported AB was recorded in 48.7%. In patients with possible AB, undergoing neuropathic pain medication showed significantly less improvement in symptoms (p=0.021) than splint therapy (p=0.009). Overall, half of the patients showed overall improvement in their TMD symptoms from the treatment combinations. Conclusion: Despite several treatment modalities, only half of the patients showed improvement in their symptoms in the present study. A standardized assessment method encompassing all factors contributing to bruxism behaviors and their consequences is suggested.