Abstract: It’s a common practice for orthodontists to extract first premolar and move canine distally to relieve crowding for patients with dental crowding. The biggest resistance for distal movement of canine is the interdental septum distal to canine after extraction of first premolar. Periodontal ligament distraction osteogenesis(PLDO) can decrease the resistance effectively and achieve the goal of rapid distal movement of canine. The histological changes of tooth movement after PLDO are similar to those of traditional tooth movement. The main difference lies in the remodeling speed. It has been confirmed that PLDO can move canine rapidly without complications in a short period.

Key words: periodontal ligament distraction osteogenesis, rapid orthodontic tooth movement, accelerate tooth movement