The 5mm length of the upper and lower teeth may be dental or bony. Because it is impossible to judge whether it is dental or bony by the length of the upper and lower teeth, it needs to be analyzed in combination with the etiology, clinical manifestations and facial shape, etc. The details are analyzed as follows: 1. Etiology: dental parietal is mostly seen in children in the period of tooth replacement, which is due to the abnormal positional relationship between upper and lower jaws caused by the process of tooth replacement. Bony pericoronitis is caused by unbalanced growth and development of jaws, and has family genetic history. 2. Clinical manifestations: Dental is only anterior anticuspension, while bony is not only anterior anticuspension, but also overdevelopment of the lower jaw and underdevelopment of the upper jaw. 3. Facial shape: Dental paronychia usually does not affect the facial shape, while osseous paronychia will affect the appearance and make the face concave. To summarize, there are many points to judge between dental and bony paronychia, which need to be viewed comprehensively, and it is recommended to consult a doctor for clarification.