Dental Abscess: This is often the most common cause of jaw swelling, particularly if it's localized to one side. A dental abscess is a collection of pus that can cause pain, swelling, and tenderness, usually as a result of a bacterial infection.

Periodontal Abscess: Similar to a dental abscess but involves the tissues surrounding the tooth, including the periodontal ligament and bone.
Cellulitis: A bacterial infection of the skin and subcutaneous tissues that can cause swelling, redness, and warmth of the affected area.
Salivary Gland Infection or Blockage: Infections or blockages of the salivary glands (like the parotid or submandibular gland) can cause swelling in the jaw area.
Trauma: A blow to the jaw can cause swelling due to hematoma formation or fracture.

Necrotizing Fasciitis: A severe bacterial infection that destroys tissue under the skin, including fat and the tissue covering the muscles (fascia). It's rare but can be life-threatening if not treated promptly.
Ludwig's Angina: A severe infection of the tissues in the neck, which can cause swelling of the jaw and neck and can lead to airway obstruction if not treated.
Osteomyelitis: An infection of the bone, which can cause swelling, pain, and redness over the affected bone.
Malignancy: Although less common, jaw swelling can be a sign of a tumor, either benign or malignant, affecting the jawbone, salivary glands, or surrounding tissues.

Actinomycosis: A rare bacterial infection that can cause abscesses or masses in the jaw area.
Sarcoidosis: A condition that can cause inflammation in various parts of the body, including the salivary glands, leading to swelling.
Tuberculosis or Other Granulomatous Diseases: Rarely, these conditions can affect the jaw and cause swelling.
Giant Cell Tumor or Other Benign Bone Tumors: These are rare and can cause swelling and destruction of the jawbone.