Overgrowth of costochondral graft in temporomandibular joint ankylosis reconstruction: A retrospective study.

Background: Temporomandibular joint (TMJ) ankylosis is a situation in which the mandibular condyle is fused to the glenoid fossa by bone or fibrous tissue. The management of TMJ ankylosis has a complicated chore, and it is challenging for the maxillofacial surgeon because of technical hitches and high rate of reankylosis. Costochondral graft (CCG) is a common treatment modality for TMJ ankylosis. One of disadvantages of CCG is unpredictability of growth pattern and risk of overgrowth. This report illustrates the fate of CCG used in the TMJ reconstruction and also the management of patients with CCG overgrowth.
Materials and Methods: A retrospective evaluation of 14 patients presented with unilateral TMJ ankylosis reconstructed using CCG treated in our hospital from 2000 to 2013 was done. Only patients with unilateral ankylosis treated by CCG with at least 2-year follow-up and complete case records with clinical and radiographic details were included in the study. Patients with bilateral ankylosis, reankylosis, missing details, and the patients with <2-year follow-up were excluded from the study. The patients were selected based on the specified inclusion/exclusion criteria. All the patients were analyzed clinically and radiographically. Facial appearance, jaw motion, occlusion, contour, and linear growth changes were documented preoperatively, immediately postoperatively, and long term (>2 years).
Results: Totally 14 unilateral temporomandibular ankylosis cases were reconstructed using CCG from the period of 2000-2013. The mean age of the patients is 5.2 years with the standard deviation of 1.48 ranging from 3 to 9 years. Follow-up of the patients ranges from 2 to 6 years with mean follow-up of 3 years. Out of 14 patients, 2 patients had normal growth of CCG after the mean follow-up of 3 years, whereas 5 patients presented with moderate growth, 4 patients with CCG overgrowth, and 3 patients presented with no growth of CCG following surgery. Overgrown CCG was treated with condylar shaving, and orthodontic elastic was maintained to stabilize the occlusion. Moderately grown and nongrowing CCG was treated by internal distractor for the management of facial symmetry. Facial asymmetry and malocclusion were successfully corrected in all patients with altered growth pattern.
Conclusion: The growth pattern of the CCG is extremely unpredictable, which can be in the form of no growth at all or excessive growth, and mandibular overgrowth on the grafted site can actually be more troublesome than the lack of growth. Care should also be taken to ensure proper postoperative functional therapy and to examine the role of cartilage thickness on future growth in young patients.