Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 6 4 2020 05 16 138 142 Mahbube Sadat Hasheminasab Department of Oral & Maxillofacial Surgery, Craniomaxillofacial Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran. Mahsa Mortazavi Department of Orthodontics, University of the Pacific, Arthur A, Dugoni School of Dentisry. Reza Sharifi Oral and Maxillofacial Surgery Department, Craniomaxillofacial Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran. Farzaneh Bolandparva Department of Oral & Maxillofacial Surgery, Craniomaxillofacial Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran. 2020 01 12 2020 04 11 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 counter clockwise 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.  Keywords: Maxillomandibular complex (MMC); Orthognathic surgery; Consequences of maxillomandibular complex rotation. https://jcr.tums.ac.ir/index.php/jcr/article/view/306 https://jcr.tums.ac.ir/index.php/jcr/article/download/306/275