Magnetic resonance imaging findings in patients with sleep bruxism: A cross-sectional study of TMJ morphology

Objective: To evaluate the relationship between self-reported sleep bruxism and temporomandibular joint (TMJ) alterations on MRI, focusing on disc morphology, disc position, and condylar changes. Methods: A total of 162 patients (135 females, 27 males; mean age 37.6 ± 13.9 years) were categorized into bruxism (n=100) and non-bruxism (n=62) groups. MRI examinations were assessed for disc morphology, disc displacement, and condylar bone changes. Logistic regression analyses were performed, adjusting for age and gender. Results: Sleep bruxism was independently associated with anterior disc displacement without reduction (ADDwoR). No significant associations were found between bruxism and disc morphology or condylar degenerative changes, including erosion, sclerosis, flattening, or osteophytes. Conclusion:.Sleep bruxism appears specifically associated with ADDwoR, rather than with morphological or degenerative TMJ alterations. These findings indicate that bruxism may primarily influence joint dysfunction through functional loading of the disc, whereas osseous remodeling likely reflects multifactorial processes. Further longitudinal studies are needed.