TEMPOROMANDIBULAR-JOINT SYMPTOMS IN AN ORTHOGNATHIC SURGERY POPULATION

The records of 317 consecutive patients who underwent orthognathic sur gery in the Division of Maxillo-Facial Surgery of the General Hospital St. John, Bruges, Belgium, between 1.10.90 and 1.10.92 were evaluated for pre- and postoperative temporomandibular joint (TMJ) symptoms. On ly 143 patients, with a normal/low angle mandibular deficiency deformi ty, treated by mandibular advancement, and 53 high angle absolute mand ibular retrognathism patients having bimaxillary operations, were sele cted. Fewer TMJ symptoms were found postoperatively, than preoperative ly in the total group (17.8% vs 26.5% p = 0.025, Mc Nemar). In the nor mal/low angle group, there was a decrease in TMJ symptoms after surger y from 30.0% to 14.6% (p = 0.0001, Me Nemar). In the high angle group, however, more TMJ symptoms are seen postoperatively 26.4% versus 16.8 % (p = 0.228, Mc Nemar). Possible hypothetical explanations are given.