The role of the disk in sheep temporomandibular joint ankylosis

• Published in: Oral surgery, oral medicine, oral pathology, oral radiology and endodontics oral medicine, oral pathology, oral radiology and endodontics, 1999-08, Vol.88 (2), p.151-158
• Main Authors: Miyamoto, Hizuru, Kurita, Kenichi, Ogi, Nobumi, Ishimaru, Jun-Ichi, Goss, Alastair N.
• Format: Article
• Language: English
• Subjects: Animals; Ankylosis - diagnostic imaging; Ankylosis - etiology; Ankylosis - pathology; Biological and medical sciences; Body Weight; Calcinosis - diagnostic imaging; Calcinosis - etiology; Calcinosis - pathology; Cartilage, Articular - diagnostic imaging; Cartilage, Articular - pathology; Cartilage, Articular - physiology; Cartilage, Articular - surgery; Dentistry; Fibrosis; Follow-Up Studies; Head and neck surgery. Maxillofacial surgery. Dental surgery. Orthodontics; Mandibular Condyle - pathology; Mandibular Condyle - physiopathology; Maxillofacial surgery. Dental surgery. Orthodontics; Medical sciences; Radiography; Range of Motion, Articular - physiology; Regeneration; Sheep; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Temporomandibular Joint - diagnostic imaging; Temporomandibular Joint - pathology; Temporomandibular Joint - surgery; Temporomandibular Joint Disc - diagnostic imaging; Temporomandibular Joint Disc - pathology; Temporomandibular Joint Disc - physiology; Temporomandibular Joint Disc - surgery; Temporomandibular Joint Disorders - diagnostic imaging; Temporomandibular Joint Disorders - etiology; Temporomandibular Joint Disorders - pathology; Wound Healing
• ISSN: 1079-2104; 1528-395X
• DOI: 10.1016/S1079-2104(99)70109-5

Objective. The purpose of this study was to determine the role of the disk in intraarticular ankylosis of the temporomandibular joint. Study design. Twelve adult sheep were divided into 2 groups. In group 1, removal of the temporal and condylar articular surfaces was performed on the right temporomandibular joint and the disk was maintained; in group 2, removal of the articular surfaces and diskectomy were performed on the right temporomandibular joint. One sheep from each group was killed just after surgery and 5 sheep from each group were killed at 3 months. The joints were examined radiologically, macroscopically, and histologically. The range of jaw movements was recorded preoperatively and at sacrifice. Results. Each of 2 sheep in group 2 had lost 4% of their body weight by 3 months; all of the other sheep maintained or increased their weight. The range of jaw motion to the right was significantly lower in group 2 than in group 1 ( P < .01). In group 1, fibrous repair of the articular surface and regeneration of the condylar head was seen. In group 2, each of the joints showed a total fibrous ankylosis with some calcification. There was a statistically significant difference in radiologic score between the groups ( P < .0001). Histologic scores for group 1 demonstrated significantly lower scores on the degree of ankylosis scale and degree of calcification scale ( P < .0001). Conclusions. This study showed that the presence of the disk prevented the development of fibrous intraarticular ankylosis of the temporomandibular joint. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88:151-8)