Temporomandibular Joint (TMJ) Disorder: This is the most likely diagnosis given the symptom of jaw pain. TMJ disorders are common and can cause pain in the jaw, face, and surrounding areas due to issues with the joint that connects the jawbone to the skull.

Bruxism: Grinding or clenching of the teeth can lead to jaw pain and is a common issue that may be related to stress, anxiety, or sleep disorders.
Dental Problems: Issues such as cavities, abscesses, or gum disease can cause pain that may be perceived as jaw pain.
Sinusitis: Inflammation of the sinuses can cause pain in the face, including the jaw area, especially if the maxillary sinuses are involved.

Myocardial Infarction (Heart Attack): Although less common, jaw pain can be a symptom of a heart attack, especially in women. It's crucial to consider cardiac causes, especially if accompanied by other symptoms like chest pain or shortness of breath.
Trigeminal Neuralgia: A chronic pain condition that affects the trigeminal nerve, which can cause intense pain in the face, including the jaw area.
Giant Cell Arteritis: An inflammation of the arteries that can cause jaw pain, especially when chewing, along with other symptoms like headache and visual disturbances.

Osteonecrosis of the Jaw: A rare condition characterized by the death of jawbone tissue, often associated with long-term use of bisphosphonates or other medications.
Jaw Tumors: Benign or malignant tumors in the jaw can cause pain and should be considered in the differential diagnosis, especially if there are other symptoms like swelling or difficulty moving the jaw.
Eagle Syndrome: A rare condition where an elongated styloid process or calcified stylohyoid ligament causes pain in the jaw and face, often mimicking other conditions.