Understanding Temporomandibular Joint Disorders and Treatments

Disorders of the temporomandibular joints Dr.Mohammed Alaraji

The temporomandibular joint (TMJ) is composed of the temporal bone and the mandible, as well as a specialized dense fibrous structure, the articular disk, several ligaments, and numerous associated muscles.

classification

1-Developmental Aplasia/ hypoplasia of the joint/ condyle Condylar hyperplasia. 2- Traumatic: a-condylar # either intra & extra articular b-tearing of disck c-sulaxation&dislocation, 3- infective condition 4-functional disturbance Disturbance of function like MFPDS Loss of function :ankylosis 5- degenerative disease a-OA & b-RA 6-neoplastic Bengin T fibrochondroma. Malignant:

Condylar hyperplasia is a rare, usually unilateral, overgrowth of the mandibular condyle. It causes facial asymmetry, deviation of the jaw to the unaffected side on opening and a crossbite The mandible grows down and forward, tilting the occlusal plane and allowing the maxillary alveolus and teeth to grow down into the space. . If the condition is still active an intracapsular condylectomy should be performed to remove the active growth centre in the condylar surface. If the disease has stabilised usually at the end of puberty or shortly afterward corrective osteotomies may be needed to restore the occlusion and facial symmetry.

Condylar hypoplasia: either occur unilateral or bilateral,in severe cases of condylar hypoplasia such as hemifacial microsomia Treatment:reconstruction of glenoid fossa & condyle

B-Subluxation &dislocation of(T.M.J Subluxation is defined as an excessive abnormal excursion of the condyle secondary to flaccidity and laxity of the capsule, or a condition where the condylar head moves anterior to the eminence on wide opening, while the mouth can be closed again quite easily. Radiographically, the glenoid fossa often shows flatness, with atrophy of the articular eminence. of the TMJ is a condition where the Acute dislocation condyle moves suddenly ventral to the articular eminence and becomes locked in front of it.

Chronic recurrent dislocation is characterized by a condyle that slides over the articular eminence catches briefly beyond the eminence and then returns to the fossa. Most patients find that they can reduce their condyle to the normal position.

The pathogenesis of chronic recurrent subluxation or dislocation of the TMJ has been attributed to trauma and abnormal chewing movements. It is found more frequently in people with general joint laxity and in patients with internal derangement of the TMJ or with occlusal disturbance. Patients often complain of difficulty in mastication and speech

Management isolated acute dislocation events: stimulation of the gag reflex may be successful in some situations; manipulation via sustained pressure on the posterior teeth to overcome masseteric spasm; post-reduction management: facial bandage, non- steroidal anti-inflammatory drugs (NSAIDs), muscle relaxant, patient to support chin when yawning.

Minor procedures O ften successful for recurrent dislocation: autologous blood injection to the joint space; sclerosant injection to the joint space; botulinum toxin injection to the pterygoid muscles, these can be combined with a period of IMF.

Open surgical/ arthroscopic For recurrent dislocation &sublaxation : augment eminence, e.g. downfracture zygomatic arch remove eminence, e.g. eminectomy capsulorrhaphy. For chronic dislocation myotomies/ coronoidectomy; condylectomy

tearing of disc the meniscuos is torn free at one margin & crumpled up with in the cavity,so the movement of condyle is then restricted. Treatment is menisectomy.

Ankylosis is the most severe insult to (TMJ) structures and to mandibular growth and function in children. Trauma to the joint during the growth period always ends with ankylosis due to the destruction and the damages to the cartilaginous layer of the joint with fragmentation of the disk and damages to the specialized mesechymal layer that is mediated for adapting, remodeling, and repair of the condyle.

Important causes of ankylosis ( true or intracapsular ankylosis) 1. 2. 3. 4. Trauma Infection Arthritides Neoplasms of the joint

Clinical Presentation 1. Patients with fibrous or bony ankylosis present with restricted mandibular motion . Unilateral pathology in children may result in significant problems with lower facial symmetry. A shortened ramus on the affected side is usually accompanied by a prominent antegonial notch noted on radiographs. Such unilateral mandibular growth disturbances have secondary effects on the maxillary occlusal plane and midfacial structures 2. 3. Ankylosis in adults is characterized by limited jaw opening, but the morphologic characteristics found in the growing patient are frequently absent. An associated anterior open bite is frequently noted with the loss of ramus/condyle height .

Treatment 1-Reconstruction With a Chondro-Osseous Graft in Children 2. Reconstruction with a 2-part chrome-cobalt prosthesis. 3. Reconstruction with a Silastic dimethyl- polycyloxaine (rubber silicone) implant. 4. Reconstruction by the use of temporalis muscle interposition Arthroplasty

Temporomandibular pain dysfunction syndrome Temporomandibular joint (TMJ) pain dysfunction syndrome refers to a common triad of jaw clicking, jaw locking (or limitation of opening) and/or pain This afflicts young people mainly, typically teenagers or young adults, especially females Trauma and stress appear to predispose Management is variously by rest, exercise or other therapies

Septic arthritis (of a native joint) Three routes of entry: haematogenous (most common); spread of local infection; direct inoculation (e.g. penetrating trauma). Most common organisms: S. aureus; Neisseria spp.; Haemophilus spp.; Streptococcus spp.

clinically present as a jaw deviation, limited opening, and pain investigation joint aspirate for microscopy and culture and sensitivity Treatment is with IV antibiotics but aspirational drainage or open debridement may be required

Rheumatoid arthritis is an autoimmune disease of unknown cause. The disease target is the synovial membrane, which is infiltrated by inflammatory cells, enlarges and grows across the joint surface causing resorption and joint destruction. The main features are chronic inflammation of many joints, pain and progressive limitation of movement of small joints. Radiography shows flattening of the condyles with loss of contour and irregularity of the articular surface as typical findings. The joint space may be widened by exudate in the acute phases but later narrowed. and the margins of the condyles become irregular.

Management Patients may be taking a range of medications including non-steroidal anti-inflammatory drugs, and colloidal gold injections, methotrexate, azathioprine, If joint symptoms are severe, a corticosteroid injection into the joint space may reduce pain and swelling. There is no effect of steroids on disease progression and no evidence that they can allow normal condylar growth.

Osteoarthritis is a disorder of cartilaginous repair. Alterations in cartilage matrix appear to be the cause and are linked to several gene defects. Erosion of cartilage causes resorption of the underlying bone, which distorts, collapses and becomes sclerotic in response. New bone grows at the edge of the joint (osteophytes), limiting movement, and the capsule and ligaments are thickened. Inflammation is mild. Trauma and diabetes also predispose. Treatment is symptomatic, and anti-inflammatory analgesics are the main line of treatment. Corticosteroid injections have been tried, in late stage do high shave operation

Neoplastic Diseases Tumors affecting the TMJ area are exceedingly rare. The tissues from which a neoplasm may arise include the synovium, bone, cartilage, and associated musculature.