성견에서 편측성 하악 과두돌기의 탈구성 골절시 체외적출을 이용한 관혈적 정복술과 보존적 치료의 비교 실험적 연구

The experimental comparative study of the surgical and conservative treatment of unilateral dislocated fractured mandibular condyles in the mature dog

This study is to evaluate the results of surgical and conservative treatment of the unilateral disolocated fractured mandibular condyles in mature dog. The conservative treatment of the fractured condyle in its dislocated position outside the glenoid fossa is grouped as A . In group A, no functional treatment was performed, but immediate postoperative active jaw movement was performed by chewing the solid food. The surgical treatment by completely detaching the condyle, then replacing it as free graft and its subsequent fixation with interosseous wring is grouped as B . Immediate postoperative mandibular function was performed in both groups. In both groups, we performed simulated retrodiscal injury and discal displacement by incision. Radiologic, and histologic examinaions were conducted on all animals. We got the following results. 1. The radiographic examination showed the good union of fractured line. In conservative treatment group(Group A), double condylar appearance was observed at 12 weeks. In open reduction group(Group B), the condylar overgrowth was noted at 8 weeks irregular condylar surface was observed at 12 weeks. 2. The initial inflammatory reaction was disappeared gradually. In both groups, favorable condylar remodeling change was observed. In conservative treatment group, the chondroid tissue was growing from the fractured margin and was replaced by new bone. But complete condylar reformation was not observed at 12 weeks and fractured segment was remained without complete resorption. In open reduction group, nearly normal joint structure was observed at 8 weeks. But the condylar surface was irregular and exophytic bony change was observed partly. None of the condyles were lost as result of necrosis in open reduction group.