Are Vowels Normalized After Maxillary Osteotomy? An Acoustic Study in Cleft Lip and Palate

BACKGROUND Maxillary hypoplasia is a common skeletal condition in cleft lip and palate (CLP). Maxillary osteotomy is typically used to reposition the maxilla in CLP with maxillary hypoplasia. Previous studies have suggested that vowel articulations are adjusted postsurgically due to altered vocal tract configuration and articulatory reorganization. This acoustic study aims to investigate whether vowels are normalized postoperatively and to explore the nature of articulatory reorganization. METHODS AND PROCEDURES A prospective study was conducted to examine the vowel production of a group of individuals with CLP (N = 17) undergoing maxillary osteotomy and a group of normal controls (N = 20), using speech acoustic data. The data were collected at 0 to 3 months presurgery (T1), 3-months (T2), and 12-months (T3) postsurgery. General linear model repeated measures and independent t-tests were undertaken on F1, F2, and vowel space area. RESULTS General linear model repeated measures revealed no main effects of time for F1 (F [2, 22] = 1.094, P = 0.352), F2 (F [2, 22] = 1.269, P = 0.301), and vowel space area (F [2, 28] = 0.059, P = 0.943). Independent t-tests showed statistically significant differences (P