Vertical ramus elongation and mandibular advancement by endobuccal approach: Presentation of a new osteotomy technique.

INTRODUCTION: Several surgical procedures have been proposed for the treatment of hyperdivergent dentoskeletal deformities. We propose a new osteotomy technique allowing for lengthening and advancement of the mandibular ramus by intra-oral approach.

SURGICAL PROCEDURE: This technique differs from the conventional sagittal split osteotomyin that which the anterior osteotomy line is not continued until the basilar edge but stopped 5-6mm above it. Cutting of the pterygomasseteric sling is systematically done allowing for the lowering of the mandibular angle. Osteosynthesis is performed by transjugal and intra-oral approaches, using two adjustable miniplates. Our supra-angular technique allows for both elongation of the ramus and advancement of the mandible. Unlike the vertical ramus osteotomy proposed by Caldwell-Letterman, external incision and intraoperative cervical hyperextension are not required.