TMJ, or temporomandibular joint, connects the lower jaw to the skull and controls jaw functions like chewing. Temporomandibular disorder (TMD) can cause pain in the joint or chewing muscles and is caused by stress, clenching, or teeth grinding. Symptoms of TMD include jaw pain, trouble chewing, clicking sounds, and headaches. Teeth grinding in particular can lead to enamel wear, dentin exposure, and tooth sensitivity. If you suspect TMD, see a medical professional for diagnosis and treatment options like pain relievers, night guards, behavioral changes, or in severe cases, surgery.