Enlarged jaw can be caused by trauma, tonsillitis, enlarged submandibular lymph nodes, acute periapical inflammation and so on. 1. Trauma: Trauma to the jaw due to collision, fall, etc. causes inflammatory edema in the soft tissues, resulting in jaw enlargement. 2. Tonsillitis: severe tonsillitis may cause lymph node hyperplasia, resulting in jaw enlargement. 3. Enlarged submandibular lymph nodes: due to inflammation in the throat, infection in the mouth, etc., the submandibular lymph nodes are enlarged, resulting in the above symptoms. 4. Acute periapical inflammation: acute periapical inflammation is caused by trauma, pulp necrosis, etc., which leads to periapical abscess, tooth pain, weakness, etc., and therefore the jaw is swollen. You should go to the hospital in time and treat the symptoms.