Salivary Antioxidant Levels in Chronic Temporomandibular Disorders Patients

Objectives: Temporomandibular disorders (TMD) are most common orofacial pain disorders of non-dental origin. Etiology and pathophysiology of TMD are multifactorial and not clarified, but patients often relate aggravation of symptoms to increased levels of stress. Psychological or mechanical stressors can generate free radicals that can exacerbate tissue damage and pain. The aim of this study was to investigate the relationship between antioxidant parameters and TMD.

Methods: Twelve subjects with chronic TMD and 15 healthy subjects were included in the study. The DC/TMD questionnaire was used to determine the presence of TMD, and the visual analogue scale was used to measure pain caused by TMD.
Five milliliters of whole unstimulated saliva were collected twice daily (7:00 AM and 5:00 PM). Saliva aliquots, (1 ml), were stored at −80°C until analyzed. Saliva samples were thawed and centrifuged prior to analysis (1000xg, 5 min). Superoxide dismutase (SOD), total antioxidant capacity (TAC) and uric acid (UA) were analyzed using spectrophotometric methods. Mann–Whitney test was used to compare salivary antioxidant levels between patients with TMD and the control group.

Results: There were significant differences in the mean salivary levels of TAC (? < 0.001) between the groups, whereas the mean salivary levels of SOD and UA were higher in the TMD group but without statistical significance.

Conclusions: Higher levels of antioxidants are more frequently observed in the healthy group, which would indicate that oxidation-related stress in the body is effectively balanced by antioxidants. However, the higher levels of antioxidants in TMD patients, as compared to healthy controls obtained in our study, probably reflects an effort of antioxidant system to counteract the excessive oxidant stress present in TMD (, i.e. it rather is a result of a compensatory increase of antioxidants to the oxidant stress in diseased states).