Transverse maxillary arch changes with the use of preoperative orthopedics in unilateral cleft palate infants.

A retrospective clinical study, using a reflex microscope, measured arch widths, palatal shelf widths, cleft widths, and palatal shelf angulation from 26 sets of plaster models of infants' maxillary arches at birth, and at 3 and 6 months. All infants had unilateral clefts of the lip and palate. They were treated with active preoperative orthopedics until lip repair at 3 months and with a passive plate until palate repair. Cleft width significantly decreased during these periods, due to transverse growth, along with relative flattening of the palatal shelves. Arch width contracted slightly anteriorly, but remained stable posteriorly. Preoperative orthopedics may have helped these changes by removing the effects of the tongue action and allowing unrestricted growth of the palatal shelves.