dental disorders
Overview of Temporomandibular Disorders (TMDs)
Diagnosis of Temporomandibular Disorders
Clinical evaluation Disorders of the temporomandibular joint (TMJ) must be distinguished from the many conditions that mimic them (see table). Pain exacerbated by finger pressure on the joint when the mouth is opened implicates the TMJ. Patients are asked to describe the pain and designate painful areas. Typically, muscles of mastication (temporalis, masseter, and medial pterygoids) and the cervical and occipital muscles are palpated for general tenderness and trigger points (spots that radiate pain to another area). The lateral pterygoids cannot be directly palpated. Patients are observed opening the mouth as wide as is comfortable. When patients open their mouth, the mandible typically deviates toward the painful side. Palpation and auscultation of the joint during opening and closing may reveal tenderness and catching and intracapsular sounds such as clicking/popping or crepitus. Condylar motion can best be palpated by bilaterally placing the middle fingers on the preauricular areas (lateral poles of the condyle) and exerting gentle medial pressure or by placing the 5th fingers into the external ear canals and exerting very gentle forward pressure as patients move their jaw. The average-sized patient can open the mouth at least 40 mm (measured between the incisal edges of the upper and lower central incisors). To account for differences in patient size, a patient should typically be able to fit 3 fingers (index, middle, ring) into the mouth up to the distal interphalangeal joints. 