Effects of Balancing Side Interferences on Tooth Mobility and Temporomandibular-Disorders

OBJECTIVES: Occlusal interferences are the premature contacts between the opposing teeth that are inhibiting or altering the movements of the mandible. In natural dentitions while there is contact between the opposing teeth on the working side, there is no contact on the balancing side. During construction of fixed prosthesis, this condition has to be maintained. An undesirable balancing tooth contact may be effective not only on the TMD but on the tooth mobility as well. The purpose of this study is to evaluate the effects of balancing side interferences on the tooth mobility with periotest and the effects on TMD with clinical examination and questionnaire. METHODS: In this study, 20 patients having fixed prosthesis with balancing side interferences for at least four years were evaluated. TMJ and muscle clinical examinations were performed and a questionnaire were given to the patient for the evaluation of TMD and tooth mobility tests were done with periotest, and the contralateral sound molar teeth without balancing interferences were tested as a control group. Balancing side interferences were eliminated by placing renewed restorations and, two months later mobility tests were repeated. The pre and posttreatment data were statistically compared with Student-t test and Paired-t test. RESULTS: No clinically correlation was observed between balancing side interference and TMD, and the tooth mobility values were in the normal range. Although the posttreatment values were less then pretreatment values numerically, there was no statistical difference found among pre and postreatment data and control group (p>0.05). CONCLUSION: In the limitations of this study, it can be said that, balancing side interferences do not affect the tooth mobility values and cause no clinical TMD symptoms, however, during the planning of a new restoration, the other parameters such as masticatory muscle activities, TMJ vibrations, mandibular movements etc. must be taken into consideration.