Mandibular condyle remodeling and joint space after open reduction and internal fixation of mandibular parasymphysis and angle fractures: a retrospective study.

OBJECTIVES

Mandibular fractures, especially at the parasymphysis and angle, significantly affect the temporomandibular joint (TMJ) due to remodeling. This study assesses changes in condyle volume, morphology, and position after open reduction and internal fixation (ORIF) using 3D analysis methods.

MATERIALS AND METHODS

A retrospective study evaluated 16 patients (11 males, 5 females; mean age: 33.63 years) with parasymphysis fractures, categorized into isolated (PS-type) and those with angle involvement (A-type). Preoperative and postoperative CBCT scans (minimum 6-month follow-up) were analyzed. Volumetric, linear, and angular changes in the condyle were assessed on the fractured and non-fractured sides.

RESULTS

Significant postoperative condylar volume increase was observed on both fractured (p = 0.0081) and non-fractured sides (p = 0.0453). In PS-type fractures, condylar volume (p = 0.0156) and height (p = 0.0352) significantly increased on the fractured side, with a marked inter-side volumetric difference (p = 0.0232). A-type fractures showed a significant increase in sagittal condylar position on the non-fractured side (p = 0.0078). No other parameters showed significant change across or within groups. Correlation analyses revealed no significant association between condylar volume change and patient age or follow-up time.

CONCLUSION

TMJ remodeling after ORIF varies by fracture type. Isolated parasymphysis fractures caused significant increases in condylar volume and height. Angle fractures involvement showed greater sagittal positional. These results highlight the impact of fracture location and mechanical force distribution on adaptive remodeling.