Temporomandibular Joint Dysfunction

Abstract

Temporomandibular joint (TMJ) dysfunction is a chronic pain condition characterized by pain in the joint that can also radiate into surrounding anatomical structures such as the ear, mandible, or neck. The TMJ is a true joint that contains an upper and lower synovial cavity with an articular disk located between the two cavities. The pain associated with TMJ dysfunction is usually related to inflammation or instability of the intracapsular disk, but may also be related to the muscles surrounding the joint, including the temporalis, internal and external pterygoids, and the masseter. Other muscles that may be involved include the trapezius and sternocleidomastoid. TMJ dysfunction should be carefully distinguished from other possible etiologies of pain with similar facial patterns, such as giant cell arteritis, trigeminal neuralgia, otitis, and complex regional pain syndrome. Diagnostic work-up of TMJ dysfunction can involve imaging modalities such as dental X-rays, panoramic radiographs, CT, MRI, and scintigraphy, as well as more invasive options such as arthroscopy of the TMJ. Treatment for TMJ dysfunction starts with conservative therapies including patient education, physical therapy, behavior modification, and oral orthotic devices. Oral pharmacologic agents such as Ibuprofen, Cyclobenzaprine, Gabapentin, and Amitriptyline have also been shown to help relieve symptoms. If conservative management is not effective, intra-articular injection of the joint with a combination of local anesthetic and steroid can be performed. Other injections such as intra-articular hyaluronate and injection of botulinum toxin into the temporalis and masseter muscles have been studied. Surgeries are performed on the TMJ itself to correct structural etiologies of dysfunction and are considered if more conservative therapies are not effective.