[Complications occurred in root canal mechanical preparation: the reason, prevention and management]

Root canal preparation is one of the important procedures in root canal treatment as well as one of the key factors to the success of root canal treatment. It consists root canal cleaning and shaping, and further provides a favourable condition for root canal obturation. Because of the complexity and irregularity of root canal system, complications may occur during the root canal mechanical preparation, such as root canal ledges, transportations, perforations, instruments separating and flare ups. Understanding the reason and management of root canal mechanical preparation complications is helpful to prevent its occurrence and to reduce the unfavourable prognosis as well. This article discusses and systematically analyzes the reason, prevention and management of the complications in root canal mechanical preparation, in order to enhance the awareness of clinicians on these complications.