A comparative evaluation of osteosynthesis with lag screws, miniplates, or Kirschner wires for mandibular condylar process fractures

Abstract

Purpose: This study compared the clinical and radiologic outcomes of open treatment of mandibular condylar process fractures using lag screws, miniplates, or Kirschner wires.

Patients and methods: Open reduction and internal fixation was performed for severely displaced or dislocated mandibular condylar process fractures in 23 patients (26 fractures) using Eckelt lag screws, in 10 patients (10 fractures) using Kirschner wires, and in 21 patients (22 fractures) using miniplates. Clinical and radiologic evaluations were made 6 months postoperatively and at final follow-up (mean, 18.4 months; range, 7 to 106 months). Radiologic evaluation included accuracy of reduction of the fractured condylar processes and changes in ramus height.

Results: Most fractured condylar processes (approximately 90%) were repositioned precisely in all groups. A shortening of the ramus of more than 5 mm was observed significantly more frequently (P <.05) in the miniplate group than in the lag screw group at 6 months. The condyles were severely resorbed in 2 or 3 patients in each group. All of these patients were associated with malunion, and partial bone resorption of the condyles was seen during the first 6 months. The relation between reduction or screw position and bone healing in patients treated with lag screws indicated that correct reduction and screw insertion allowed normal bone healing. The patients in all groups showed satisfactory clinical results. No significant intergroup differences were noted in maximum mouth opening and laterotrusion. However, deviation during mouth opening was significantly greater (P <.05) in cases treated with miniplates than with lag screws.

Conclusion: Lag screw osteosynthesis may be more advantageous for restoration of ramus height than miniplates or Kirschner wires.