How does apicitis occur?

The most common infection comes from dental pulp disease, followed by periodontal disease secondary through apical foramen attached root canal and dentin tubule, blood-borne infection is relatively rare, at present, it is considered that the main pathogen of periapical disease infection is mixed infection with anaerobic bacteria as the main body, melanobacterium is the main pathogen of acute apical radicitis. Bite hard objects such as sand biting into rice, walnut biting, bottle cap biting, traumatic occlusion can cause periapical damage, dental factors, excessive dental pulp and root canal sealing, root canal instruments penetrating the apex, improper orthodontic force, rapid tooth separation, careless tooth extraction and adjacent teeth can cause periapical damage.