True eminectomy for internal derangement of the temporomandibular joint

We carried out a prospective study to assess the short- and long-term outco mes of true eminectomy in 20 consecutive patients with type III or IV anter iorly displaced discs in whom conventional conservative treatment had faile d to resolve the symptoms. Maximum opening was measured preoperatively, 3-6 months postoperatively and at one year postoperatively, Each patient fille d out a Mandibular Functional Impairment Questionnaire [MFIQ] and Clinical Dysfunctional Index both preoperatively and one year postoperatively, Imagi ng records included preoperative and one year postoperative orthopantomogra ph (OPG) and magnetic resonance imaging (MRI). Maximum mouth opening one ye ar postoperatively had increased in 95% of patients (range 5-20 mm, mean 12 mm), There was an improvement in symptoms, using the MFIQ, in 85% of patie nts. The Clinical Dysfunctional Index was reduced to Type I in most patient s. MRI showed increase in rotation and translatory movement of the condylar head. We conclude that true eminectomy may be used to successfully treat t ype III and type IV anteriorly displaced discs in patients who have failed to respond to conventional conservative treatment. (C) 2000 The British Ass ociation of Oral and Maxillofacial Surgeons.