Temporomandibular ankylosis in the cat: a review of seven cases

Abstract

Ankylosis of the temporomandibular joint (TMJ) in the cat is an unusual complication of traumatic lesions involving articular (true ankylosis) or periarticular structures (false ankylosis). Seven cats with true ankylosis of the TMJ (four cases unilateral and three cases bilateral), of which previous trauma had been documented in five cases, were referred to the authors' clinic between September 1991 and October 1996. Radiographic assessment was performed in all cases, using dorsoventral and oblique projections. Five subjects underwent arthroplastic excision of the TMJ and, in the remaining two cases, stretching of the jaws was performed under general anaesthesia. The surgical outcome was satisfactory in all but one case, where partially decreased joint mobility was observed (follow-up time one to five years), but in the two cases where non-surgical treatment was carried out, recurrence of TMJ ankylosis was observed (follow-up time two to five months). In the authors' experience, surgery represents the treatment of choice for TMJ ankylosis in cats. Additional mandibular symphysiotomy can confirm the radiological findings in unilateral cases.

Temporomandibular joint ankylosis and salivary mucocele in a cat: case report

“…Some complications may occur after excision arthroplasty of temporomandibular joint, especially in bilateral cases. In general, however, acceptable cosmetic and functional results have been observed in experimental and clinical cases reported in dogs and cats (Lantz et al, 1982;Tomlinson and Presnell, 1983;Meomartino et al, 1999). In this case, unilateral removal of the lateral aspect of the condyloid process was effective in reestablishing normal function.…”

“…In general, chronic ankylosis makes the detection of the primary lesion difficult (Meomartino et al, 1999). It was hypothesized that the cat of this report, initially, suffered a trauma resulting in temporomandibular luxation that was responsible for the malocclusion.…”

“…Because the cat was not properly treated, false temporomandibular ankylosis developed. Traumatic episodes reported to have resulted in ankylosis include luxation of the condylar process and fractures of zygomatic arc, condyloid process, retroarticular process, and coronoid process ( Van EE and Pechman, 1987;Lantz, 1991;Meomartino et al, 1999). The length of left mandible body was smaller than the right, probably, because the ankylosis developed during skeletal growth.…”

“…Because conservative treatment is always unsuccessful (Sullivan, 1989;Meomartino et al, 1999), surgical treatment is considered the best option. The surgical procedure should restore jaw motion and avoid the recurrence by removing the ankylosed tissue and, if necessary, the mandibular condyle (Sullivan, 1989;Lantz, 1991;Okumura et al, 1999).…”

“…In cats, most reports are associated with trauma ( Van EE and Pechman, 1987;Sullivan, 1989;Okumura et al, 1999). Conservative treatment using corticosteroids and forced stretching of the jaw is generally ineffective (Sullivan, 1989), and may result in relapse one month after the procedure (Meomartino et al, 1999). The best results are obtained with procedures such as condylectomy, partial zygomatic arch resection, coronoidectomy and resection of proliferative bone (Van EE and Pechman, 1987;Sullivan, 1989;Meomartino et al;Okumura et al, 1999).…”