2Fiorelli G, Melsen B, Modica C. The design of custom orthodontic mechanics[ J]. Clin Orthodontics Res,2000,3 (4) :210 - 219.
3Miller RJ, Duong TT, Derakhshan M. Lower incisor extraction treat- ment with the Invisalign system [ J]. J Clin Orthod, 2002,36 ( 2 ) : 95 - 102.
4All SA, Miethke HR. Invisalign,an innovative invisible orthodontic appliance to correctmaloeclusions : advantages and limitations [ J ]. Dent update ,2012,39 (4) :254 - 256,258 - 260.
5Germane N, Lindauer SJ, Rubenstein LK, et al. increase in arch perimeter due to orthodontic expansion[ J]. Am J Orthod Dentofa- cial Orthop, 1991,100 ( 5 ) :421 - 427.
6Pavooi C, Lione R, Lagana G, et al. Self-ligating versus Invisalign : analysis of dento-alveolar effects [ J ]. Ann Stomatol, 2011,2 ( 1/ 2) :23 -30.
