Objective:Ibuprofen – a non-steroidal anti-inflammatory drug (NSAID)- and glucosamine sulfate – a natural compound and a food supplement- are two therapeutic agents which have been widely used for treatment of patients with temporomandibular joint (TMJ) disorders. This study was aimed to compare the effectiveness and safety of these two medications in the treatment of patients suffering from TMJ disorders.Methods:After obtaining informed consent, 60 patients were randomly allocated to two groups. Patients with painful TMJ, TMJ crepitation or limitation of mouth opening entered the study. Exclusion criteria were history of depressive disorders, cardiovascular disease, musculoskeletal disorders, asthma, gastrointestinal problems, kidney or liver dysfunction or diabetes mellitus, dental diseases needing ongoing treatment; taking aspirin or warfarin, or concomitant treatment of TMJ disorder with other agents or methods. Thirty patients were treated with ibuprofen 400 mg twice a day, (mean age 27.12 ± 10.83 years) and 30 patients (mean age 26.60 ± 10) were treated with glucosamine sulfate 1500 mg daily. Patients were visited 30, 60 and 90 days after starting the treatment, pain and mandibular opening were checked and compared within and between two groups.Findings:Comparing with baseline measures, both groups had significantly improved post-treatment pain (P < 0.0001 for both groups) and mandibular opening (P value: 0.001 for glucosamine sulfate and 0.03 for ibuprofen). Post treatment pain and mandibular opening showed significantly more improvement in the glucosamine treated patients (P < 0.0001 and 0.01 respectively). Rate of adverse events was significantly lower in the P value glucosamine sulfate group (P < 0.0001).Conclusion:This investigation demonstrated that comparing with a commonly prescribed NSAID – ibuprofen-, glucosamine sulfate is a more effective and safer therapeutic agent for treatment of patients with TMJ degenerative join disorder.