6Kavadia-Tsatala S, Tsalikis L, Kaklamanos EG, et al. Orthodontic and periodontal considerations in managing teeth exhibiting significant delay in eruption[J]. World J Orthod, 2004, 5 (3):224- 229.
7Sarver DM, Yanosky M. Principles of cosmetic dentistry in orthodontics: Part 3. Laser treatments for tooth eruption and soft tissue problems[J]. Am J Orthod Dentofacial Orthop, 2005, 127 (2) : 262-264.
8Grover PS,Lorton L.The incidence of unerupted permanent teeth and related clinical cases[J].Oral Surg Oral Med Oral Pathol,1985,59(4):420-425.
9Becker A.The orthodontic treatment of impacted teeth[M].London:Martin Dunitz Limited,1998:1-40.
