The effect of an interfragmentary gap on the clinical outcome after mandibular angle fracture surgery

Abstract

The mandibular angle fracture occasionally widens at the lower border after surgery using a single miniplate. However, the effects of an interfragmentary gap have not been fully investigated. The aim of this study was to determine the effects of gaps caused by mandibular angle fracture surgery using a single superior border miniplate technique. In this prospective study, the interfragmentary gap was measured by panoramic radiography and cone-beam computed tomography (CBCT) postoperatively. The width of the gap measured by panoramic radiography and CBCT scans was compared. The patients were divided into two groups based on the gap width (more or less than 1.5 mm). In CBCT scans, bucco-lingual displacement of the proximal segment was evaluated. Clinical results and complication rates were investigated according to the gap and displacement. The findings were statistically analyzed. Thirty-two patients were included in the study. The mean interfragmentary gap widths were 1.56 ± 0.83 mm by panoramic radiography and 2.12 ± 0.87 mm by CBCT scans. CBCT measured a gap width of approximately 0.5 mm wider than panoramic radiography (P = 0.001). Twenty-two patients (68.8%) had an interfragmentary gap width of >1.5 mm, and ten patients (31.2%) had a gap width of <1.5 mm. All patients had favorable occlusion at the last clinical examination. There were no statistically significant differences in intermaxillary fixation periods and complication rates (P > 0.05). One patient in the wider gap group experienced pain in the temporomandibular joint when opening the mouth. Six patients (18.8%) had lingual displacement of the proximal fragment. Displacement did not significantly influence the complication rate (P > 0.05). The presence of an interfragmentary gap after mandibular angle fracture surgery did not affect the clinical outcome.