Temporomandibular Joint Dysplasia Research Articles

Temporomandibular joint injections in dogs with temporomandibular joint pain: 11 cases (2015-2019).

To describe and evaluate the clinical application of temporomandibular joint injections using betamethasone and ropivacaine in German Shepherd dogs suffering from non-odontogenic orofacial pain due to temporomandibular dysplasia and/or osteoarthritis. Outcomes in dogs presented with clinical signs of non-odontogenic orofacial pain associated to temporomandibular joint dysplasia and/or arthritis and treated with a temporomandibular joint injection were retrospectively-prospectively evaluated. The overall clinical signs free period ranged between 25 to 1579 days, with an average of 461 days. The clinical signs free period for temporomandibular joint osteoarthritis scores 1, 2 and 3 were on average 659 days (180-1579 days), 134 days (42-355 days) and 723 days (25-1377 days), respectively. Similarly the temporomandibular dysplasia scores 1, 2 and 3 were on average 306 days (26-1579 days), 1377 days and 669 days (25-1429 days) respectively. Those dogs in which only one side was injected the clinical signs free period average was 639 days (25-1578 days), compared with dogs in which both temporomandibular joints were injected showing a clinical signs free period average of 378 days (42-1377 days). The temporomandibular joint injection technique proved to be feasible with a decent outcome in dogs suffering from non-odontogenic orofacial pain associated with temporomandibular joint osteoarthritis and/or dysplasia. Further randomised studies are required to confirm the effectiveness of this intervention.

Progress of temporomandibular joint prosthesis

The anatomically and functionally complex nature of the temporomandibularjoint (TMJ) makes its reconstruction one of the most challenging tasks faced by surgeons who operate in the head and neck. TMJ prosthesis is one of the important techniques in the reconstruction of TMJ. The main indications for TMJ prosthesis include ankylosis, fractures of condylar that can't be fixed, trauma or tumor, end-stage TMJ disturbance, and TMJ dysplasia caused by Hallermann-Streiff syndrome. TMJ replacement aims to enhance the function of TMJ, alleviate pain, and prevent serious complications. TMJ prosthesis is advantageous in oral and maxillofacial surgery because it can imitate normal anatomic morphology and adhere to the host. Moreover, the use of other materials is no longer necessary and functional training can be started postoperatively at once, among others. Prosthetic materials have leading and promoting functions in the development of joint prosthesis. Good design, fit shape, and fixation are the necessary conditions for prosthesis to serve its function. Investigation of joint biomechanics is also necessary. With the rapid developments in material science, joint biomechanics, and other related subjects, TMJ prosthesis has been significantly improved in terms of its materials, design, fit shape, and fixation techniques. In addition, the development of TMJ prosthesis would expand its applications. This review intends to provide an overview about the progress and clinical application of TMJ prosthesis.

Overexpression of Shox2 leads to congenital dysplasia of the temporomandibular joint in mice.

Our previous study reported that inactivation of Shox2 led to dysplasia and ankylosis of the temporomandibular joint (TMJ), and that replacing Shox2 with human Shox partially rescued the phenotype with a prematurely worn out articular disc. However, the mechanisms of Shox2 activity in TMJ development remain to be elucidated. In this study, we investigated the molecular and cellular basis for the congenital dysplasia of TMJ in Wnt1-Cre; pMes-stop Shox2 mice. We found that condyle and glenoid fossa dysplasia occurs primarily in the second week after the birth. The dysplastic TMJ of Wnt1-Cre; pMes-stop Shox2 mice exhibits a loss of Collagen type I, Collagen type II, Ihh and Gli2. In situ zymography and immunohistochemistry further demonstrate an up-regulation of matrix metalloproteinases (MMPs), MMP9 and MMP13, accompanied by a significantly increased cell apoptosis. In addition, the cell proliferation and expressions of Sox9, Runx2 and Ihh are no different in the embryonic TMJ between the wild type and mutant mice. Our results show that overexpression of Shox2 leads to the loss of extracellular matrix and the increase of cell apoptosis in TMJ dysplasia by up-regulating MMPs and down-regulating the Ihh signaling pathway.

IMAGING DIAGNOSIS—TEMPOROMANDIBULAR JOINT DYSPLASIA IN A BASSET HOUND

A 5-month-old intact male Basset Hound presented for evaluation of pain and crepitation during manipulation of the temporomandibular joint, worse on the right side. A computed tomography (CT) scan of the head was performed. The CT images demonstrated the osseous features of temporomandibular joint dysplasia and facilitated a 3D reconstruction, which allowed better visualization of the dysplastic features. The patient responded to conservative management with a tape muzzle with no recurrence reported by the owner 6 months after presentation.

Temporomandibular joint morphology in Cavalier King Charles Spaniels.

Temporomandibular joint dysplasia has been reported in several breeds of dog. Three Cavalier King Charles Spaniel (CKCS) skulls were examined and radiographed during the course of a separate study and all demonstrated changes consistent with bilateral temporomandibular joint dysplasia. Subsequently, skull radiographs from all CKCS dogs examined at the University of Glasgow Veterinary School between 1991 and 2001 were reviewed (n = 26). Only two of these dogs were radiographed specifically for investigation of the temporomandibular joint, although varying degrees of dysplasia were identified in all dogs where the joints were adequately visualized (n = 20). The head of four CKCS cadavers was also radiographed, and similar changes were found. This finding suggests that temporomandibular joint dysplasia is a widespread asymptomatic condition in the CKCS and should be regarded as a normal morphologic variation rather than a pathologic anomaly. Subtle changes are best seen on lateral oblique radiographs, although marked changes are also visible on dorsoventral views. The rotational angle or angle of articulation of each of the dysplastic mandibular condyles was measured and was related to the severity of the dysplastic changes. However, there was overlap between the values calculated for these abnormal joints and normal ones in other breeds, suggesting this measurement was of limited significance and the shape of the components of the temporomandibular joint are more relevant when assessing this joint for the presence of dysplastic changes.

Bilateral Mandibular Condylectomy in a Cat

A six year old cat with a chronically luxating jaw was treated by bilateral condylectomy. The etiology of the chronic luxation was unilateral temporomandibular joint dysplasia.

Temporomandibular joint dysplasia in an Irish Setter

ABSTRACTDysplasia of the temporomandibular joints was diagnosed in an Irish Setter. The condyloid process was mis‐shapen and the glenoid fossa flattened, which allowed subluxation of the temporomandibular joints with recurrent locking of the coronoid process on the zygomatic arch with the mouth open. Permanent relief from open mouth jaw locking was given by partial zygomatic arch ostectomy.