Objective: To prospectively investigate the signs and symptoms of TMJ in patients undergoing different orthognathic operations with rigid or non-rigid internal fixation.
Methods: The Helkimo index was used to analyze the anamnestic (Ai) and clinical (Di) data of 46 one-year postoperative cases being performed mandibular ramus osteotomies combined with other operations, and compared with preoperative data to analysis the changes of TMJ symptoms.
Results: The changes of the Ai and Di data were not significant. Postoperative in the four clinical indices, only the joint tenderness indice was significantly different from preoperative. Despite there were decreases of maximal opening of mouth, maximal protrusion, they were only 1% lower than preoperative data and had no clinical significance. The percentage of TMJ to develop after bimaxillary operation was not different from only mandibular operation. There was no significant difference as compared between different operations and fixation methods.
Conclusions: The change of TMJ symptoms and signs after orthognathic surgery was not significant. Compared with each other the various surgical procedures (bimaxillary or only mandibular, BSSRO or BIVRO, RF or NRF) were not found any difference about the effect on the TMJ.