INITIAL STUDY FOR CORRELATION BETWEEN CONDYLAR FRACTURES AND TEMPOROMANDIBULAR JOINT ANKYLOSIS

Objective To explore the correlation between condylar fractures and temporomandibular joint (TMJ) ankylosis. Methods 28 patients with TMJ ankylosis in this groups, 16 males, 12 females, age 5 to 34 years, 26 patients10 years, 26 unilateral and 2 bilateral, Histomy of trauma was documented in all cases. All patients were took the orthopanotomograms, cross sectional or coronal sectional CT (two dimensional and three dimensional reconstruction were performed in some patients). But these X ray were compared with past trauma. The high osteotomy of base of zygomatic and the exploration for condylar process and meniscus were performed in the reconstruction operation of the TMJ. Results The high position condylar intracapsular fractures, serious dislocation of condylar segment, and obvious ascending of mandibular ramus were observed in CT imaging of these patients with TMJ ankylosis. The condyle of replacement was found inside the masses of bony overgrowth. The bony overgrowth was developed from the ascending ramus and the zygomatic processes. At surgery, the condyle and the meniscus of the serious replacement was found in the 20 patients (22 joints), unilateral ankylosis was only observed in 8 bilateral condylar fractures. In non affected side, 2 patients were middle or low position fracture, 4 patients were high fracture, but the condylar segment dislocation was light. Conclusion The TMJ ankylosis can be caused if the serious dislocation of the condylar segment with meniscus and ascending of the ramus occurred. For this case, the operation of open reduction and fixation should be taken.