Ultrasonic bone-cutting surgery has been recently introduced as a feasible alternative to the conventional tools of cranio-maxillo-facial surgery, due to its technical characteristics of precision and safety. The device used is unique in that the cutting action occurs when the tool is employed on mineralized tissues, but stops on soft tissues. This technical note illustrates the use of Piezosurgery for all osteotomies of surgically assisted rapid maxillary expansion (SARME). The procedure, including pterygo-maxillary detachment, can be completed under local anaesthesia. Other advantages include minimal risk of jeopardizing critical anatomic structures (e.g. palatine artery), minimal intraoperative bleeding and postoperative swelling, and minimal thermal damage to bone surfaces. Narrow and rectilinear osteotomies can be easily performed with varying vibrating scalpels, at the cost of a longer operative time.