Applications of the Novel Midpalatal Piezocorticotomy Guide for MARPE Midfacial Skeletal Expansion.

: MARPE expansion is known to produce maxillary skeletal expansion and cause subsequent increase in velopharyngeal, oropharyngeal, and nasal volume. While MARPE designs vary and may include combinations of traditional bands, traditional jackscrews, or milled/3D printed frameworks with other screw designs, there is no agreement on the techniques of MARPE expansion in adult patients. The aim of this case series is to describe a novel 3D-printed and 3D-designed midpalatal piezocorticotomy guide and its benefits for MARPE-assisted midfacial skeletal expansion. : This case series showcases the results of successful MARPE expansion in adults and introduces the novel 3D-printed midpalatal piezocorticotomy guide. It compares the outcome of non-guided piezocorticotomy-assisted maxillary skeletal expansion and outlines the benefits of pre-planned 3D-guided midpalatal piezocorticotomy. : The MARPE expansion outcomes when combined with 3D-designed and 3D-printed midpalatal piezocorticotomy guides are shown to be predictable and capable of preventing asymmetric expansion along with asymmetric suture opening. The technique, in particular, allows for one to preserve the position of the nasal septum and prevents asymmetrical nasal septum dislodgement following maxillary skeletal expansion. : The described novel midpalatal piezocorticotomy guide presents a significant improvement to adult midfacial techniques using MARPE expansion appliances.