Effects of rapid maxillary expansion on the midpalatal suture: a systematic review

To identify and qualify the scientific evidence on the immediate and long-term effects of rapid maxillary expansion on the midpalatal suture in growing teenage or young adults, the related articles were selected. Literatures were searched in the electronic databases, including Medline, Embase, Web of Science, and Cochrane Library. A methodologic-quality scoring (13-point) scale was used to evaluate the quality of the studies. Twelve relevant articles were identified. Midpalatal suture opening during orthodontic treatment with rapid maxillary expansion (RME) amounted to 12-52.5 percent of the total screw expansion. After the treatment of RME, the midpalatal suture seemed to be recalcificated, so the expansion of the midpalatal suture was stable, but there was no consistent evidence on whether the midpalatal sutural opening was parallel or triangular. The methodologic quality of the included studies was assessed rigorously and many deficiencies were found. The majority of the articles were judged to be of low quality. Therefore, we could not draw any accurate conclusion on the basis of evidence in this systematic review.