Principle of Lag-Screw Fixation in Mandibular Trauma

The aim of the study is to assess the effectiveness of lag screw fixation in mandibular fractures with respect to parameters such as stability of the occlusion, functional stability, infection rates, neurosensory deficit, ease of technique, and maximum interincisal opening.

Our study was carried out on 13 patients with mandibular fractures. Selected cases were treated with lag screw technique and 2.7 mm titanium screws were used. Postoperative complications such as wound dehiscence, infection, neurosensory disturbance, nonunion, malocclusion, postoperative mouth opening, and occlusal discrepancies were assessed.

All the patients were male, aged between 17 and 50 years. The cause of the injury was road traffic accidents in all, except for two assaults. Our study of 13 cases of fractured mandible included five symphyses, five parasymphyses, two angle, and one body fracture cases. Our observation with open reduction and rigid internal fixation with 1-2 lag screws revealed close approximation of fractured fragments in all the cases, except in three patients who had mild discrepancy of occlusion.

Lag screw technique provides good interfragmentary compression and restoration of premorbid anatomic alignment of fracture fragments. In displaced mandibular fractures, especially in oblique fractures, the use of lag screw has proven to be ideal. The complications were found to be low. It was concluded that the lag screw provided excellent stability and occlusion.