Bruxism, temporomandibular disorders, and pressure pain thresholds during fixed orthodontic treatment in adults: A prospective controlled cohort study

OBJECTIVE: To investigate whether fixed orthodontic treatment affects sleep and awake bruxism activities, temporomandibular disorder (TMD) prevalence, and pressure pain thresholds (PPTs) of masticatory muscles in healthy adults. METHODS: In this prospective controlled cohort study, 10 orthodontically treated adults and 10 age- and sex-matched untreated controls were assessed at baseline, 14 days, 1 month, and 6 months using 24-h electromyographic recordings of the masseter muscle, diagnostic criteria for TMD, and PPTs of masticatory muscles. RESULTS: No significant intra- or inter-group differences emerged in sleep or awake bruxism indices or TMD prevalence. However, orthodontic patients showed greater jaw functional limitation at 1 and 6 months, together with reduced masseter, occipital, and sternocleidomastoid PPTs between 1 and 6 months. CONCLUSIONS: Fixed multibracket therapy did not affect bruxism indices or TMD prevalence over 6 months, but was associated with transient jaw functional limitation and a modest reduction in cranio-cervical PPTs.