Condylar morphology after temporomandibular joint discectomy with interpositional abdominal dermis-fat graft.

PURPOSE: The purpose of this study was to look at the morphology of the condylar head after temporomandibular joint (TMJ) discectomy with interpositional abdominal dermis-fat grafts by using the orthopantograph (OPG) as the basis for investigation.

PATIENTS AND METHODS: This retrospective study involved 28 patients (1 male patient) who had undergone TMJ discectomy with an interpositional abdominal dermis-fat graft for the management of severe internal derangement. The age range of the patients was 15 to 68 years, with a mean age of 51.5 years at the time of their TMJ surgery. A total of 33 operated joints were examined, including 5 cases of bilateral TMJ discectomy with dermis-fat grafts. Sixteen joints underwent additional surgery to the condylar head, whereas the remaining 17 joints had no condylar surgery. OPG radiographs were taken from 12 months up to 7 years after surgery, with a mean follow-up period of 32 months. The condyles of the operated joints were visually assessed on OPG and graded according to the condylar morphology scale (CMS), where 0 indicates normal, 1 indicates remodeling, and 2 indicates resorption of the condylar head.

RESULTS: By use of the CMS grading system, 9 of 33 joints (27.3%) were found to be normal (CMS = 0). Remodeling (CMS = 1) was found in 14 joints (42.4%) after TMJ discectomy with dermis-fat graft. Radiologic evidence of resorption was present in 10 joints (30.3%) with a CMS score of 2. Remodeling (CMS = 1) was found in 3 joints (17.6%) where no condylar surgery was performed compared with 11 joints (68.8%) where condylar surgery was undertaken. Resorption (CMS = 2) was measured in equal numbers of 5 joints in each group regardless of whether condylar surgery was undertaken (31.2%) or not (29.4%).

CONCLUSIONS: The findings of this study suggest that in cases where additional condylar surgery was undertaken, over two thirds of the joints (68.8%) showed evidence of remodeling on postoperative OPGs. The interpositional dermis-fat graft failed to prevent significant condylar changes (CMS = 2) in about one third of patients who underwent TMJ discectomy, with the youngest (mean, 30.2 years) and the oldest (mean, 55.6 years) patients being most susceptible to condylar resorption.