Stability between single and segmental maxillary osteotomies in bimaxillary surgery for cleft-associated class III deformity: a CBCT study.

OBJECTIVE: Segmental Le Fort I osteotomy through the cleft is a common strategy to narrow the alveolar cleft in adults. This study compared skeletal stability between single and segmental Le Fort I osteotomies in patients with unilateral cleft lip and palate (UCLP). MATERIALS AND METHODS: This retrospective analysis examined 45 adults with complete UCLP-associated class III deformities who underwent bimaxillary surgery with either single (n = 30) or segmental (n = 15) Le Fort I advancement. Cone beam computed tomography (CBCT) scans of the facial skeleton were acquired before surgery, 1-week postsurgery, and at follow-up. Measures of landmarks from the CBCT images for the two treatment groups were compared for translation (left/right, posterior/anterior, superior/inferior) and rotation (yaw, roll, pitch). RESULTS: Postsurgery, the downward movement of the maxilla was larger in the segmental group than the single group. At follow-up, the maxilla moved backward in both groups, and upward in the segmental group. The mandible moved forward and upward and rotated upward in both groups. The amount of upward movement and rotation was larger in the segmental group than the single group. CONCLUSIONS: Two years after bimaxillary surgery in patients with UCLP-associated class III deformity, greater relapse was found after segmental Le Fort I osteotomies in vertical translation of the maxilla and mandible, and pitch rotation of the mandible compared with single Le Fort I osteotomies. CLINICAL RELEVANCE: The vertical relapse of the maxilla was larger after segmental Le Fort I advancement compared with single Le Fort I advancement in clefts.