Corticotomy-assisted rapid maxillary expansion: A novel approach with a 3-year follow-up

•Treatment duration was 5 months, with stable results at 3-year follow-up.•Piezo-bone perforation induces sufficient bone apposition without bone graft.•The thin periodontal biotype was transformed.

This case report introduces a new approach of corticotomy-assisted rapid maxillary expansion for treating a severe maxillary transverse discrepancy in a skeletally mature patient. This approach uses piezo-bone perforation in conjunction with a fixed appliance and an expander. This report describes the treatment of a 14-year-old girl with a severe maxillary transverse discrepancy. She had a straight profile, severe maxillary crowding, a maxillomandibular transverse differential index of 9 mm, and a Class I skeletal relationship. The treatment protocol consisted of surgical intervention with piezo-bone perforation and active orthodontic therapy. Immediately after the piezo-bone perforation on the lateral buccal side of the maxilla, active orthodontic therapy was started with activation of an expander. The expander was reactivated weekly. Treatment duration was 5 months 2 weeks. Proper overbite and overjet, facial balance, and occlusion were achieved. The treatment outcome was stable at the 3-year follow up. This treatment approach considerably reduced the treatment time and gained bony volume. Additionally, it transformed the periodontal biotype in contrast to conventional therapy. This approach is a good alternative for treating a severe maxillary transverse discrepancy in a skeletally mature patient, especially for a patient who does not want surgical rapid palatal expansion.