Primary Maxillary Deficiency Dentofacial Deformities: Occlusion and Facial Aesthetic Surgical Outcomes

Publication date: Available online 1 March 2018
Source:Journal of Oral and Maxillofacial Surgery
Author(s): Jeffrey C. Posnick, Sirish Makan, Daniel Bostock, Timothy J. Tremont
PurposeThe purpose of this study is to document the malocclusion and facial dysmorphology in primary maxillary deficiency (PMD) subjects with chronic obstructive nasal breathing prior to treatment and the outcomes after bimaxillary orthognathic, genioplasty, and intranasal surgery.MethodsA retrospective cohort study of PMD subjects undergoing bimaxillary orthognathic, chin, and intranasal surgery was implemented. The predictor variables were grouped into demographic, anatomic, operative, and longitudinal follow-up categories. The primary outcome variables were the initial post-operative occlusion achieved (T2, 5 weeks postoperative) and that maintained long-term (T3 or T4, > 2 years after surgery). Six occlusion parameters were assessed: overjet, overbite, coincidence of dental midlines, Angle classification, and molar vertical and transverse positions. A second outcome variable was the facial aesthetic results. Photographs were analyzed to document 7 facial contour characteristics.ResultsSixty-six subjects met the inclusion criteria. Age at operation averaged 22 years (15-55). The study included 18 females (27%). A majority of subjects (57/66, 86%) achieved and maintained a favorable occlusion for each parameter studied long-term (mean 5 years). The need for a 3 segment Le Fort I was significantly associated with long-term posterior malocclusion. Facial dysmorphology prior to surgery included the appearance of a: prominent chin (56%); flat labio-mental fold (61%); prominent lower lip (88%); prominent nose (77%); sunken midface (100%); flat cheekbones (82%); and recessed upper lip (73%). Prior to surgery, 82% of subjects exhibited at least 5 of the 7 key facial contour deformities. Correction of all 7 facial contour deformities was confirmed in 92% of subjects long term. In 8% of subjects, an overly prominent appearing chin persisted.ConclusionUsing orthognathic techniques, the majority of PMD subjects achieved and maintained a corrected occlusion long-term. In unoperated subjects, a "facial aesthetic type" was identified. Bimaxillary orthognathic and chin surgery proved effective in correcting associated facial dysmorphology in the majority.



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