关键词: 根管显微镜, 超声技术, 根管弯曲度, 根管侧穿

Abstract: Clinical evaluation of the treatment for difficult root canal with dental operating microscope and ultrasonic instruments. LU Zhi-shan*， LIU Zhong-hao， LI Hong， JIANG Guang-shui， WANG Xiang-ai， ZHAO Jun-na.* Yantai Stomatological Hospital， Yantai 264001， China
Abstract: Objective To evaluate the use of dental operating microscope and ultrasonic instruments in treating difficult root canal. Methods This paper summarized 210 difficult root canals in 177 teeth which were treated with dental operating microscope and ultrasonic instruments. Result These difficult root canals caused by broken instruments， luting cement and resinifying agent in canals， root canal calcification and root canal perforation were managed with the success rate of 82.35%， 82.14％， 76.32％and 100.00％ respectively;the incidence of root canal perforation in severe curved root canals was 35.14％during the course of the treatment. Conclusion Most of difficult root canals can be treated perfectly by the combined technique using dental operating micro scope and ultrasonic instruments; the operator should pay attention to avoiding root canal perforation when treating severe root canals curvature obstruction resulted from various factors .

Key words: dental operating microscope, ultrasonic technique, root canal curvature, root canal perforation