Abstract: Objective To observe clinic effects on replacing teeth of serious periodontal disease by teeth of auto-transplantation instantly after treating two years. Methods To substitute teeth that suffer from serious periodontal disease for auto- transplantation teeth through guided tissue regeneration technique after basic therapy, clinic effects were observed by investigating periodontal index after therapy 6, 12 months and two years. Results Clinic effects on replacing teeth which suffer from serious periodontal disease by 9 teeth of auto- transplantation were very satisfied excepted for 3 teeth that lost after treating 6, 12 months and two years. Conclusion Teeth with serious periodontal disease can be substituted by the third molar teeth that no functions of auto- transplantation in this clinic study.