Fractures of the maxilla are clinically divided into low horizontal fractures, high horizontal fractures, sagittal fractures, and alveolar fractures, as follows: 1. low horizontal fractures: the main clinical manifestation is the disorder of the occlusal relationship, and the principle of treatment is to restore the normal occlusal relationship. 2. high horizontal fractures: the manifestation is the disorder of the occlusal relationship and facial deformity, and the main principle of treatment is to restore the occlusal relationship, and also to correct the facial deformity. The main treatment principle is to restore the occlusal relationship and also to correct the facial deformity. 3. sagittal fracture: a vertical fracture of the maxilla, the fracture line is often located in the middle, manifesting as a widening of the dental arch, which may appear as a disorder of the occlusal relationship, and the fracture may injure the skull base. 4. alveolar eminence fracture: this fracture often requires surgical treatment.