Jiang-Ming Li1, Jin-Gang An1, Xiao Wang2, Ying-Bin Yan3, E Xiao1, Yang He1, Yi Zhang4. 1. Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Peking University, Beijing, China. 2. Department of Stomatology, Peking University Third Hospital, Beijing, China. 3. Department of Oral and Maxillofacial Surgery, Tianjin Stomatological Hospital, Tianjin, China. 4. Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Peking University, Beijing, China. Electronic address: zhangyi2000@263.net.
Abstract
OBJECTIVE: We aimed to study the pathology underlying traumatic temporomandibular joint ankylosis (TMJA). STUDY DESIGN: Specimens from 10 patients with traumatic TMJA were categorized using the Sawhney classification and were decalcified and stained with hematoxylin-eosin, alcian blue/periodic acid-Schiff, alizarin red, and Masson stains. Immunostaining with anti-CD34 antibody was performed. Computed tomography and pathologic findings were compared. RESULTS: Ankylosed areas consisted of fibrocartilaginous tissues. Bone formation occurred by osteophyte extension from the osteochondral surface toward the mass center. Endochondral ossification and osteophyte proliferation, alone or simultaneously, participated in bony ankylosis. Sequestra in the cartilaginous ankylosis preferentially formed bony bridges. Newly formed capillaries participated in ossification from the bony surface of the bone-cartilage junction; bone formed around the capillaries. Osteoclasts were present at the capillary tips. CONCLUSIONS: Types II and III were cartilaginous-bony ankylosis, with similar components. Bony traumatic TMJA was formed by osteophyte proliferation and endochondral ossification.
OBJECTIVE: We aimed to study the pathology underlying traumatic temporomandibular joint ankylosis (TMJA). STUDY DESIGN: Specimens from 10 patients with traumatic TMJA were categorized using the Sawhney classification and were decalcified and stained with hematoxylin-eosin, alcian blue/periodic acid-Schiff, alizarin red, and Masson stains. Immunostaining with anti-CD34 antibody was performed. Computed tomography and pathologic findings were compared. RESULTS: Ankylosed areas consisted of fibrocartilaginous tissues. Bone formation occurred by osteophyte extension from the osteochondral surface toward the mass center. Endochondral ossification and osteophyte proliferation, alone or simultaneously, participated in bony ankylosis. Sequestra in the cartilaginous ankylosis preferentially formed bony bridges. Newly formed capillaries participated in ossification from the bony surface of the bone-cartilage junction; bone formed around the capillaries. Osteoclasts were present at the capillary tips. CONCLUSIONS: Types II and III were cartilaginous-bony ankylosis, with similar components. Bony traumatic TMJA was formed by osteophyte proliferation and endochondral ossification.