Objective: To compare speech outcome and velopharyngeal (VP) status of subjects with repaired cleft palate who underwent either conventional Le Fort I osteotomy or maxillary distraction osteogenesis to correct maxillary hypoplasia.
Design: Prospective randomized study with blind assessment of speech outcome and VP status.
Subjects: Twenty-two subjects were randomized into conventional Le Fort I osteotomy and Le Fort I distraction groups. All were native Chinese (Cantonese) speakers.
Method: Perceptual judgment of resonance and nasal emission, study of VP structures by nasoendoscopy, and instrumental measurement by nasometry. Assessments were performed preoperatively and at 3 months postoperatively.
Main outcome measures: Assessment of VP closure, perceptual rating of hypernasality and nasal emission, nasalance, and amount of maxillary advancement.
Results: There was no statistical difference in any of the outcome measures between the 10 subjects with conventional Le Fort I osteotomy and the 12 subjects with maxillary distraction: hypernasality (chi-square = 3.850, p = 0.221), nasal emission (chi-square = 0.687, p = 0.774), VP gap size (chi-square = 1.527, p = 0.635, and nasalance (t = -0.145, p = 0.886). There was no correlation between amount of maxillary advancement and any of the outcome measures (p = .05 for all). Changes in VP gap size and resonance are described.
Conclusion: Results need to be interpreted with caution because of the small sample size and early follow-up. However, this study utilized an assessment protocol involving a variety of outcome measures and careful consideration of reliability factors, which can be a model for further and follow-up studies.