Purpose: The long-term outcome of bilateral and unilateral ramus osteotomies used for the treatment of unilateral condylar hyperplasia of the mandible are evaluated and compared.
Materials and methods: Thirteen cases of unilateral condylar hyperplasia of the mandible were surgically treated during a 10-year period from 1985 to 1995. Seven of the patients were treated by bilateral ramus osteotomies alone; six were treated by unilateral ramus osteotomies of the affected side. Unilateral ramus osteotomy was combined with a maxillary Le Fort I procedure in two of the six cases. Preoperative analysis of patients, indications for case selection, and postoperative results relating to facial symmetry, temporomandibular joint (TMJ) pain, occlusion, and stability were compared in the two groups.
Results: The postoperative findings and long-term results in both groups of patients were favorable. Symmetry, arch coordination, and occlusion remained stable. TMJ pain and dysfunction were invariably cured postoperatively. Unilateral ramus osteotomies alone, or in combination with maxillary surgery when deemed feasible and applicable by preoperative clinical analysis, was sufficient to restore symmetry and occlusion in dentally compensated cases.
Conclusions: This study shows that patients with unilateral condylar hyperplasia of the mandible and deviation can be treated favorably by unilateral ramus osteotomy of the affected side; bilateral ramus osteotomy did not have any advantage in such cases. In addition, this procedure, combined with a Le Fort I osteotomy of the maxilla, was also effective in restoring occlusal canting and facial symmetry in dentally compensated cases. However, bilateral ramus osteotomy was required in prognathic cases and in cases in which a unilateral procedure would cause excessive rotation of the contralateral condyle.