J Korean Soc Plast Reconstr Surg.  1999 Sep;26(5):890-897.

Compression osteosynthesis Of Dsplaced Subcondylar Fractures using Lag Screws

• Lee EH
• Kim NB

Abstract

Conservative or surgical methods have been used for the treatment of fracture of mandibular subcondyle, but consensus has not been reached in regard to the proper management of this injury. Several problems related to the surgical procedure have led many surgeons to avoid surgical management of condylar fractures in favor of closed reduction and intermaxillary fixations. However, luxation of the condyle may lead to various long-term complications such as open bite on the contralateral side, dysfunction, deviation in opening and closing movements, as well as bone apposition leading to ankylosis. As a consequence, open reduction is preferable when the condyle is displaced. Various methods-for example, direct wiring technique, simple bone plating, dynamic compression plating-have been advocated for the treatment of fracture of mandibular subcondyle. Of such methods, a functionally-stable osteosynthesis can be achieved by compression osteosynthesis methods. Lag screw osteosynthesis is essentially a form of compression osteosynthesis in which the bone fragments are bound to one another as a result of traction from the screw. An advantage of compression osteosynthesis is that the end of a fractured bone can be maintained in an opposed position under pressure, and then primary bone healing occurs by direct osteoblastic activity within the fracture. As well, it obviates or reduces the need for maxillomandibular fixation, as well as the morbidity associated with conventional treatment methods such as facial nerve injury and bone resorption due to wide dissection. We have treated 9 cases of displaced subcondylar fractures of the mandible with the lag screw fixation system which is marketed by the Martin corporation. Mobilization and guidance of the jaw was begun from 7 or 10 days postoperatively. The radiologic and clinical evaluations showed good repositioning of the fragments and good occlusion postoperatively The disadvantage is that surgical procedures are relatively compound, and an additional procedure - removal of lag screw - is necessary after complete bone union. Lag screw osteosynthesis can be added as a another valid armament for plastic surgeons in the management of mandibular subcondyle fractures.

MeSH Terms

Ankylosis
Bone Resorption
Consensus
Facial Nerve Injuries
Jaw
Jaw Fixation Techniques
Mandible
Open Bite
Osteoblasts
Traction