Background and Objective: Bruxism is involuntary, excessive grinding, clenching, or rubbing of teeth during nonfunctional movements of the masticatory system, and bruxism can occur during the day or night. Teeth grinding is present in about five to eight percent of adults, although some authors have even reported higher figures. The etiology is multifactoral and has been reported to include central factors such as emotional stress, parasomnias, traumatic brain injury, neurologic disabilities, and morphologic factors such as malocclusion, muscle recruitment. In the previous studies, it has been examined the association between bruxism and TMD symptoms, but the results are not conclusive and their inter-relationship is still far from being explained. The objective of this study was to compare signs and symptoms of TMD in subjects with and without bruxism.

Patients and Methods: The sample comprised 99 subjects with TMD, and the subjects were divided into 2 groups: 58 samples with bruxism and 41 samples without bruxism. The symptoms of TMD were evaluated according to the Craniomandibular Index [CMI]. In addition, Craniomandibular pain complaints of subjects were evaluated.

Results: It was determined there was a statistically significant difference in Mandibular Movement, Extra-Oral Palpation of Jaw, Neck Muscles, Palpation Index and Craniomandibular Index between both groups. There was a significant difference between with and without bruxism groups in cheek, teeth and shoulder pain.  However, it was determined there was a statistically significant difference in Craniomandibular Total Pain Score between both groups.

Conclusions: Within the limitations of this study it can be concluded that there was an important association between signs and/or symptoms [limits in range of motion, pain during mandibular movement, tenderness in extra-oral jaw muscles and neck muscle] of TMD, craniomandibular pain and bruxism.