Arthrosis deformans of the temporomandibular joint – colloquially called temporomandibular joint arthrosis – (synonyms: osteoarthritis; osteoarthritis of the temporomandibular joint) is a chronic degenerative joint disease that can affect the temporomandibular joint, but also other joints. It results from many years of incorrect or excessive stress, for example as a result of persistent dysfunction. The disease also occurs as a result of trauma.
Symptoms – complaints
The main symptom of the disease is pain, which occurs functionally. Crepitation (bone rubbing) occurs in the affected joint, mouth opening is often restricted in the course, and lateral deviations develop.
The disease can be divided into two different courses:
- Type I occurs in older age. Initially, only one joint is affected; in the course, both joints are affected. After a phase of up to 18 months, spontaneous remission occurs, which means that the symptoms decrease on their own or with the help of conservative functional therapy. The patients have a sliding joint after the symptoms subside, which often lacks the discus (cartilaginous buffer between the temporomandibular joint head and socket).
- Type II, on the other hand, takes a different course. After dysfunction or trauma (injury), it comes to the typical symptoms. The complaints increase in the course, conservative therapy does not lead to improvement of symptoms.
Pathogenesis (disease development) – etiology (causes)
Often, long-standing dysfunctions or parafunctions (hyperfunctions that deviate from the norm, such as teeth grinding and tongue or teeth clenching) are the cause of the development of the disease.
Continuous malfunctioning or overloading can also lead to the development of the disease. Likewise, it is possible for arthrosis deformans to occur after trauma or even without an identifiable cause.
- Trauma – for example, fractures (fracture) of the joint head.
- Arthritis of the temporomandibular joints
- Lack of lateral support zones
- Habitual dislocation (dislocation; complete or incomplete loss of contact (subluxation) of joint-forming bone ends) of the temporomandibular joint.
Consequential diseases
As a result of arthrosis deformans, there is often the development of a discoid slip joint.
Diagnostics
Radiologically, osteolysis of the capitulum (joint head) is apparent, and destruction of the articular surfaces occurs as the disease progresses.
Radiographs show marginal jaggedness of the condyle surface and narrowing of the joint space, but it is not possible to determine whether the disease is type I or II. Therefore, a period of 18 months should be waited and conservatively treated before, if necessary, the indication for surgical therapy.
Arthroscopy (joint endoscopy) can be used to assess the extent of joint destruction. At the same time, diagnostics can be combined with treatment such as lavage (French lavage, “washing,” “washing,” “cleaning”).
Therapy
All osteoarthritis deformans is initially treated conservatively by functional therapy, usually with splints, for 18 months, because only then is it possible to distinguish between types I and II.
If the therapy remains unsuccessful, arthroscopic lysis (dissolution) and lavage are often first performed as part of an arthroscopy. This results in a significant reduction in symptoms in up to 40 percent of patients.
Intra-articular hydrocortisone injections can be performed under local anesthetic (local anesthesia) and help relieve symptoms.
If there is no improvement, surgical therapy is indicated. In the course of arthroplasty, the residual disc is removed and the irregular joint surface is smoothed.
Only in very severe cases or recurrences does a condylectomy (removal of the joint head) with subsequent autogenous replacement (usually a constochondral graft) sometimes have to be performed.
