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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adolescent, Adult, Analysis of Variance, Bone Plates, Bone Screws, Cephalometry, Equipment Design, Humans, Maxilla, Middle Aged, Nasal Bone, Orthodontics, Corrective, Osteotomy, Le Fort, Retrospective Studies, Statistics as Topic, Zygoma.
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Do comparison of the postsurgical stability of the Le Fort I osteotomy using 2- and 4-plate fixation? Context: This study was conducted to evaluate the postoperative stability of Le Fort I osteotomies accomplished with 2-plate versus 4-plate fixation. This is a retrospective study involving 32 patients who underwent Le Fort I 1-piece osteotomy concurrent with orthodontic therapy. All patients were treated by 1 attending surgeon during an 18-month period. Sixteen patients were treated by plate and screw fixation consisting of 4 miniplates (group I), and an additional 16 patients were treated using 2 miniplates (group II). In group I, fixation was accomplished with 2.0-mm low-profile Lorenz (Walter Lorenz Surgical Inc, Jacksonville, FL) plates and screws placed at the piriform aperture and at the maxillary buttress. Four screws were placed in each of the plates. In group II, fixation was accomplished with 2.0-mm low-profile Lorenz plates and screws placed at the piriform aperture. Again, 4 screws were placed in each of the plates. Serial cephalometric evaluation at arbitrary anterior nasal spine and posterior nasal spine for both groups showed that postoperative skeletal changes in the direction of the surgical movement were seen in approximately 20% of cases; these changes averaged less than 1 mm. Postoperative skeletal changes opposite to the direction of the surgical movement were seen in approximately 30% of cases; these changes also averaged less than 1 mm. No postoperative skeletal changes were seen in approximately 50% of cases. For all measured changes about arbitrary anterior nasal spine and posterior nasal spine, there was no significant difference between groups I and II.
assistant
This study suggested that postoperative skeletal changes associated with the use of 2-plate fixation do not appear to differ significantly from those seen with 4-plate fixation. Final Decision: yes