TMJ

The temporomandibular joint (TMJ) is the paired articulation between the mandible and the temporal bone, located in front of each ear. It is a complex synovial joint that includes the mandibular condyle, the articular disc, the joint capsule, and surrounding ligaments. The TMJ enables both hinge movements for opening and closing and translational movements for protrusion, retrusion, and lateral jaw motion.

The articular disc divides the joint into superior and inferior compartments and helps cushion movement. The joint is supported by ligaments, including the temporomandibular ligaments and surrounding muscular attachments. Movement is produced by the masticatory muscles, notably the lateral pterygoid, masseter, temporalis, and medial pterygoid.

Temporomandibular disorders (TMD) describe a group of conditions that affect the TMJ and/or associated muscles. Symptoms commonly include jaw pain or tenderness, restricted movement, jaw locking, clicking or popping sounds, headaches, ear fullness, or facial pain. Risk factors include bruxism (teeth grinding), malocclusion, trauma, arthritis, stress, and female sex; many cases are self-limiting or persistent.

Diagnosis relies on history and examination, with imaging used as needed (panoramic radiographs, CT for bone, MRI for disc position and soft tissues). Differential diagnoses include dental disease, sinus or ear disorders, and neuropathic pain.

Initial management emphasizes noninvasive measures: patient education, soft or bland diet, heat or cold, nonsteroidal anti-inflammatory drugs, physical therapy, and occlusal splints if indicated. Address contributing factors and refer to a specialist for persistent symptoms. In selected cases, procedures such as arthrocentesis, arthroscopy, or open joint surgery may be considered.