Maxillary expansion: a retrospective study of three methods of expansion and their long-term sequelae.

This study is retrospective, comparing and contrasting the effects of expansion of the maxillary arch, and its long-term stability, with the use of either a rapid maxillary expansion appliance, quadhelix, or removable appliance. Transverse alteration in the intercanine and intermolar widths were studied, as were the alteration in the inclination of the canine and molar teeth during this period.