Evaluating the remodeling of condyles reconstructed by transport distraction osteogenesis in the treatment of temporomandibular joint ankylosis.

PURPOSE

This study aimed to evaluate the remodeling of condyles reconstructed by transport distraction osteogenesis (DO) in patients with temporomandibular joint (TMJ) ankylosis.

PATIENTS AND METHODS

Twenty-one patients with 26 affected joints were followed up for 34.1 ± 13.3 months. Patients who had undergone gap arthroplasty and TMJ reconstruction by DO were included. Maximal mouth opening (MMO) and occlusion were recorded. Computed tomography images were obtained preoperatively (T0), upon completing distraction (T1), upon removal of the distraction device (T2), and >2 years postoperatively (T3). The following were measured: mandibular ramus height, distance between gonion and Frankfurt plane (Go-FN), condylar width, and condyle-ramus angulation.

RESULTS

Of the 21 patients, one showed re-ankylosis, while five exhibited anterior open bite. From T1 to T3, the total amount of resorption of ramus height reached up to 8.2 ± 4.6 mm (p < 0.001), in comparison with a total distraction length of 13.8 ± 4.1 mm; the mean resorption rate was 59.4%. Similarly, Go-FN decreased by 6.2 ± 4.0 mm (p < 0.001).

CONCLUSION

Our findings indicated that DO combined with gap arthroplasty was an effective method for the treatment of TMJ ankylosis to improve MMO. The reconstructed condyle exhibited a high frequency of resorption in height.