3Ferrazzini G. Uprighting of a deeply impacted mandibular second molar. Am J Orthod Dentofacial Orthop, 1989,96(2): 168-171.
4Shapira Y,Borell G,Nahlieli O, et al. Uprighting mesially impacted mandibular permanent second molars. Angle Orthod,1998,68(2):173-178.
5Alessandri Bonetti G,Pelliccioni GA,Checchi L. Managementof bilaterally impacted mandibular second and third molars.J Am Dent Assoc,1999,130(8) : 1190-1194.
6Sawicka M, Racka-Pilszak B,Rosnowska-Mazurkiewicz A. Uprighting partially impacted permanent second molars. Angle Orthod,2007,77(1) : 148-154.
7Miao YQ,Zhong H. An uprighting appliance for impacted mandibular second and third molars. J Clin Orthod, 2006,40(2):110-116.
8Slodov I, Behrents RG, Dobrowski DP. Clinical experience with third molar orthodontics. Am J Orthod DentofacialOrthop,1989,96(6):453-461.