Jaw pain can be caused by a temporomandibular joint disorder, or it can be caused by periapical inflammation of the teeth. TMJ disorder is not a single disorder, but a group of disorders that manifest as pain in opening the mouth or soreness in the chewing muscles. It may be associated with trauma, stress, cold irritation, and nocturnal teeth grinding. Pain can also be aggravated by large mouth opening movements, such as biting off half an apple in one mouthful, sudden biting of hard objects, etc. leading to elongation or tearing of ligaments in the joint area and jaw pain. Periapical inflammation of the teeth can also trigger swelling of the lymph nodes in the jaw and jaw pain. Sliding lymph nodes can be palpated in the jaw and improve after root canal treatment of the tooth. Therefore, jaw pain is associated with TMJ disorders and apical inflammation, and it is recommended to visit a dentist.