Zhao's training in micro-root canal therapy was a complete success. From May 4th to 6th, 2002/KLOC-0, the training office of microscopic root canal therapy and apical surgery sponsored by Kean Dental Training Management Center was successfully held in Jinan Kean Dental Harmony Square Branch. At present, root canal therapy is the most effective and predictable treatment for pulp diseases and periapical diseases. Due to the improvement and rapid development of new equipment, new technology, new instruments, new materials and new ideas, new techniques and methods of root canal therapy have been widely and well applied.