The common causes of a swollen palate are: 1. The jaw roots of the maxillary first or second molars are thicker, and inflammatory secretions from the apical region can damage the alveolar bone when periapical inflammation occurs, forming an abscess in the upper jaw, which needs to be drained by opening the pulp under local anesthesia and placing a medicinal twist to drain the pus into the mouth. If the x-ray shows a large area of alveolar bone loss around the root of the jaw, apicoectomy or root amputation is required. 2.If you eat too hot food or dry hard food, swelling and masses will form when the mucosa of the upper jaw is damaged, you need to pay attention to oral hygiene and cleanliness, local disinfection, and the fluid in the packet will gradually absorb and heal. 3.A mass will form in the upper jaw when you eat seafood or take certain drugs that cause allergic reactions, you need to Take anti-allergy drugs.