Rotation of the maxillomandibular complex in orthognathic surgery; A Review

Abstract

Introduction: In orthognathic surgery, maxillomandibular complex (MMC) refers to a three-dimensional dento-osseous structure consisting of the surgically-mobilized part of the maxilla together with the distal segment (i.e., tooth bearing segment) of the mandible (either surgically mobilized or not). In fact, MMC is the skeletal part of the lower face. The size, shape And position of MMC play a major role in soft tissue esthetics of the lower face. Materials and methods: A comprehensive review of the current data regarding effects of maxillomandibular complex rotation in sagittal plane, on “occlusal plane, TMJ, sleep apnea, paranasal soft tissues, upper lip, chin, cervicomental soft tissues” was conducted. Results: MMC rotation and translation could take place in any of the three planes of reference including sagittal, coronal, and horizontal. Any kind of changes in the position of MMC could have its own functional and esthetic consequences. In general, patients with convex facial profiles require counterclockwise rotation while patients with concave profiles require clockwise rotation. Conclusion: MMC not only has great impacts on facial esthetics, but also has significant functional effects, for example in breathing and mastication. Alteration in the position of MMC is possible by orthognathic surgery.