Posterior Maxillary Segmental Osteotomy–A Paradigm Shift From Orthognathic Surgery to Preprosthetic Surgery: A Case Report

Severe supraeruption of maxillary molars following loss of opposing mandibular teeth can critically reduce interarch space and compromise implant-prosthetic rehabilitation. When extrusion is extensive, orthodontic intrusion or prosthetic reduction may be impractical. Posterior maxillary segmental osteotomy (PMSO), classically indicated in orthognathic surgery, can be repurposed as a pre-prosthetic intervention to restore vertical dimension and occlusal harmony. Two patients presenting with missing mandibular posterior teeth and marked supraeruption of opposing maxillary molars exhibited interarch space of <5 mm. After clinical and radiographic evaluation, PMSO was planned to reposition the extruded maxillary posterior segment. Osteotomy lines were executed under local anesthesia, and the segment was repositioned using a prefabricated surgical stent for guidance and stabilization. Simultaneous placement of endosseous implants was performed in the mandibular posterior region. Patients were followed radiographically and clinically to assess bony union, implant osseointegration, pulpal vitality, and segment stability. Both cases demonstrated satisfactory repositioning of the maxillary segment with immediate restoration of interarch space adequate for prosthetic rehabilitation. Follow-up imaging confirmed successful bony union and implant osseointegration. No postoperative complications, including segmental necrosis, relapse, or pulpal injury, were observed. Definitive prosthetic rehabilitation was completed after three months with stable occlusal relationships and improved function. PMSO can serve as a predictable pre-prosthetic surgical option for immediate correction of severe dentoalveolar extrusion when conventional orthodontic or prosthetic methods are not feasible. This approach facilitates restoration of interarch space and enables successful implant-supported rehabilitation with favorable functional outcomes.