2Dodson TB, Richardson DT. Risk of periodontal defects after third mo- lar surgery: an exercise in evidence-based clinical decision-making [ J]. Dral MaxiUefac Surg Clin North Am,2007,19 (1) :93-98.
3Fickl S, Zuhr O, Wachel H, et al. Tissue alterations after tooh extrac- tion with and without surgical trauma:A volumentric study in the bea- gle dog[J]. J Clin Perioddntol,2008,35(4) :356-363.