Intracapsular condylar fracture of the mandible: our classification and open treatment experience.

PURPOSE

We studied the classification of intracapsular condylar fracture (ICF) of the mandible based on coronal computed tomography (CT) scans and present our open treatment experience at the temporomandibular joint (TMJ) division of Shanghai's Ninth People's Hospital (Shanghai, China).

MATERIALS AND METHODS

From 1999 to 2008, 229 patients with 312 ICFs were treated in our division. Among them, 195 patients (269 joints) had CT scans for classification. We modified the classification of Neff et al, adding a new fracture type according to our experience: type A, fracture line through lateral third of condylar head with reduction of ramus height; type B, fracture line through middle third of condylar head; type C, fracture line through medial third of condylar head; and type M, comminuted fracture of condylar head. There was no ramus height reduction in fracture types B and C. Our treatment protocol is open reduction for a fracture in which the superolaterally dislocated ramus stump is out of the glenoid fossa or any type of fracture with displaced or dislocated fragments that may cause TMJ dysfunction later.

RESULT

Among the 269 joints, 116 had type A fractures (43.1%), 81 had type B fractures (30.1%), 11 had type C fractures (4.1%), and 58 had type M fractures (21.6%); 3 joints (1.1%) had fractures that were not displaced. Of the joints, 173 had open reduction-internal fixation; postoperative CT scans showed that 95.6% of these had absolute anatomic or nearly anatomic reduction. In all of them normal mouth opening and occlusion were restored. No or little deviation was found during mouth opening. Complications were pain in the joint (n = 1), crepitations (n = 2), and facial nerve (temporal branch) paralysis (n = 1). Two patients had the plate removed because of these complications.

CONCLUSION

Our new classification based on CT scans can better guide clinical treatment. Open reduction for ICF can restore the anatomic position for both the condyle and TMJ soft tissues with few complications, which can yield better functional and radiologic results.