This study was performed to diagnose the existence and the degree of TMJ dysfunction using Pantronic-PRI and to investgate the degreeof dysfunction under treatment and to evaluate the period until dysfunction were disappeikared. For this study, 12 patients who had visited at the TMJ Clinic of Dankook University were investgated with Pan-PRI. 8 exper imental group patients were treated with occlusal splint therapy and 4 control group patients were not altered of occlusion during this study. The results were as follows. 1. Occlusal splint therapy was effective on treatment of TMJ dysfunction. 2. in the slight dysfunction group, dysfunction was disappeared after 4-5 weeks since occlusal splint therapy was started. 3. Pan-PRI is useful to evaluate the existence of TMJ dysfunction, the degree of dysfunction results of treatment with occlusal splint therapy and to decide other occlusal treatment modalies.