Retromandibular Approach versus an Endoscope-assisted Transoral Approach to Treat Subcondylar Fractures of the Mandible

Kim, Dong Woo; Park, Dae Song; Lee, Sang Chil; Kim, Sung Yong; Lim, Ho Yong; Yeom, Hak Yeol; Kim, Hyeon Min

Abstract

PURPOSE
Patients who had a subcondylar fracture with a displaced or deviated condylar segment were treated with a retromandibular approach (RMA) or an endoscope-assisted transoral approach (EATA) in our department of oral and maxillofacial surgery. The clinical results of the approaches were compared. A comparative study of specific approaches for subcondylar fractures has not been published before in Korea.
METHODS
Twenty-one patients with subcondylar fractures of the mandible were included. Ten patients were treated with the retromandibular approach and 11 were treated with an endoscope-assisted transoral approach. We examined patient age, gender, fracture sites, classifications, period of maxillomandibular fixation, facial nerve (FN) or greater auricular nerve (GAN) injuries, maximal mouth opening, deflection, occlusal changes, number of plates, follow-up period, and other complications. Preoperative computed tomography and pre-operative, post-operative, and follow-up panoramic views were taken of each patient.
RESULTS
Mean maximal mouth openings were similar between the two approaches. FN and GAN injuries were more frequent in the RMA group but the deflective rate with mouth opening was higher in the EATA than that in RMA group. Two cases of post-operative infection occurred in the EATA group, and occlusal changes were observed in one case for both approaches.
CONCLUSION
The RMA offers more direct access and visualization of the surgical field but it can cause scars and retractive injuries of the FN and GAN. But, EATA did not result in consequent nerve injuries or scars postoperatively, but unfavorable fractures such as medial override condyles were more difficult to reduce endoscopically. Except cases of an expected difficult reduction, the treatment of choice for a displaced subcondylar fracture may be an EATA.