Old pain in one side of the jaw after tooth extraction may be related to osteomyelitis of the jaw, periapical inflammation, jaw fracture and other causes, which need to be differentiated and diagnosed by the doctor. 1. Osteomyelitis of the jaw: if the wound is infected by bacteria and other pathogens after tooth extraction, osteomyelitis of the jaw may be caused, and the symptom of constant pain on one side of the jaw may appear. 2. Apical inflammation: If the periapical inflammation is not cured when the tooth is extracted, the inflammation may spread after the tooth is extracted, which may lead to the symptom of pain on one side of the jaw. 3. Jawbone fracture: If the jawbone is fractured due to violence during tooth extraction, it may also cause constant jawbone pain. It is recommended to go to the regular hospital in time after the extraction of one side of the jaw bone pain, to clarify the cause of the disease, under the guidance of the doctor for standardized treatment, so as to avoid the delay in the condition of the body to bring adverse effects.