RESUMO
PURPOSE: To analyze, using 3-dimensional photogrammetric data, midfacial soft tissue and volumetric changes in the cleft maxilla after 1- or 2-piece Le Fort I (LF1) advancement. MATERIALS AND METHODS: This was a retrospective study of patients with cleft and maxillary hypoplasia who underwent LF1 advancement. The primary predictor variable was the type of advancement (1 piece vs 2 pieces). Outcome measurements were changes in soft tissue linear measurements (subnasale [Sn], labium superius [LS], and stomion [SO]) and midfacial volume after maxillary advancement. RESULTS: Eleven patients (7 male, 4 female) underwent LF1 advancements (4 underwent 2-piece advancement). The mean maxillary advancement was 6.2 ± 1.7 mm. Soft tissue changes at the Sn, LS, and SO were 5.2 ± 2.0, 5.8 ± 2.5, and 5.2 ± 1.8 mm, respectively. The average volume change was 12.2 ± 5.7 cm(3). The mean ratios of soft tissue change to the amount of maxillary advancement (millimeters per millimeter) at the Sn, LS, and SO were 0.89 ± 0.49, 0.97 ± 0.44, and 0.89 ± 0.34, respectively. Volume increased by 2.1 ± 1.3 cm(3)/mm. Patients undergoing 1-piece advancement had greater mean advancement and greater soft tissue changes at the LS and SO (P < .03). After controlling for the amount of advancement, 1-piece LF1 osteotomy showed significantly greater improvements at the LS and SO (P < .04). CONCLUSIONS: Midface advancement at the LF1 level in patients with cleft consistently expands upper lip soft tissue and midfacial volume. Greater changes at the LS and SO were seen with 1-piece than with 2-piece osteotomy.