Purpose: To compare the efficacy of low-dose laser therapy to that of conservative treatment using two different occlusal splints (stabilization and anterior repositioning splints) in patients with internal derangements of the temporomandibular joint (TMJ).
Materials and methods: The study population consisted of patients with disc displacement with reduction diagnosed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I and Axis II. In addition, disc displacement with reduction was confirmed in all patients using TMJ ultrasonography. These tests were conducted for 6 months with an interim control in the third month. The "clicking" sound from the joint on opening and closing the mouth and the extent to which the mouth opened vertically and laterally were assessed. In all, 20 patients received low-dose laser therapy, 20 were treated with a stabilization splint, and 20 were treated with an anterior repositioning splint. In addition, 10 untreated patients were included as a patient control group, and a further 10 healthy subjects were included as a healthy control group. Changes in the condition were assessed based on the results of the RDC/TMD Axis II and with the use of an algometer.
Results: The anterior repositioning splint group showed improvement in the "clicking" sound during mouth opening. Lateral movement improved significantly in patients who received laser therapy. In the patient control group, the click disappeared during mouth opening, the algometrically determined pain improved, and the lateral movement increased. There were no statistically significant differences between groups in the improvement of vertical mouth movement or in the clicking sound during mouth closing.
Conclusion: Each treatment modality applied in this study separately produced positive results for the clicking sound, restrictions in vertical and lateral movements, and reduction of the pressure pain threshold observed in cases of TMJ irregularity. The decision regarding which treatment modality should be employed can be made based on the patient's symptoms. However, this study also indicates that TMJ derangements can resolve spontaneously when left untreated.