Maxillary changes with bone-borne surgically assisted rapid palatal expansion: A prospective study.

•The effect of bone-borne transpalatal distraction on the maxilla was investigated prospectively.•Measurements were performed on study casts and posteroanterior cephalograms.•Nonparallel expansion was observed, with more expansion anteriorly.•The maxillary halves tipped slightly buccally.•Arch perimeter increased upon transpalatal distraction.