IntroductionThe incidence of temporomandibular joint (TMJ) involvement in inflammatory arthritis is often underestimated, and experience in treatment among rheumatologists is limited. Three conditions have an affinity toward the TMJ: Rheumatoid arthritis (RA), psoriatic arthritis (PA), and ankylosing spondylitis (AS). The prevalence is the highest in RA, followed by PA (1-5).The disease processes differ from those seen in osteoarthritis or following trauma, which are characterized by degeneration or ankylosis, respectively, as joint destruction occurs. Furthermore, inflammatory arthropathies are systemic diseases that can lead to a relapse in symptoms, despite initially successful treatment, as TMJ inflammation continues. Immunosuppressive therapies used to ameliorate systemic inflammation may also complicate treatment responses, particularly if surgical management is required, as there is a theoretical increased risk of infection. In contrast, osteoarthritis symptoms may stabilize, previous joint trauma tends not to deteriorate unless TMJ ankylosis ensues, and immunosuppression is not required. Therefore, a different management approach is required in patients with inflammatory arthropathy that addresses both the systemic illness and localized TMJ disease.Pain, reduced mouth opening, joint noises, locking, and difficulty eating are the predominant symptoms and can be debilitating if left untreated. Pain originates from the TMJ itself, the associated masticatory muscles, or from both these areas, and it is manifested by tenderness on palpation of the respective anatomical area. Mouth opening is measured as the gap between the tips of the upper and lower incisors at maximal opening (interincisal distance) with less than 35 mm considered abnormal (6). Joint noises and locking result from the internal derangement of the joint mechanism, which consists of the mandibular condyle, intra-articular disc, and glenoid fossa, or from inflammatory debris deposited as part of the disease process. Combined with pain and restricted opening, these contribute toward problems in eating.
151Many conditions may affect the temporomandibular joint (TMJ), but its incidence in individual joint diseases is low. However, inflammatory arthropathies, particularly rheumatoid and psoriatic arthritis and ankylosing spondylitis, appear to have a propensity for affecting the joint. Symptoms include pain, restriction in mouth opening, locking, and noises, which together can lead to significant impairment. Jaw rest, a soft diet, a bite splint, and medical therapy, including disease-modifying antirheumatic drugs (DMARDs) and simple analgesia, are the bedrock of initial treatment and will improve most symptoms in most patients. Symptom deterioration does not necessarily follow disease progression, but when it does, TMJ arthroscopy and arthrocentesis can help modulate pain, increase mouth opening, and relieve locking. These minimally invasive procedures have few complications and can be repeated. Operations to repair or remove a damaged in...