Analysis of the Abnormal Characteristics of Alveolar Sounds in Postoperative Palatoplasty Patients and Rehabilitation Methods.

Abstract

The aim of this study was to analyze and compare the error types of alveolar sounds /s/, /ts'/, and /ts/ (ie, fricative and affricate sounds) in different ethnic groups (Han, Uyghur, Kazakh) after palatoplasty. The goal was to provide a basis for clinical assessment and effective intervention. A total of 68 patients who had undergone palatoplasty in our hospital's maxillofacial surgery department were retrospectively selected; all presented with alveolar sound abnormalities. These patients were divided into 3 age groups: 3.5 to 6 years, 7 to 13 years, and 14 years and above. Among them were 39 Han, 18 Uyghur, and 11 Kazakh patients. All had a good velopharyngeal function, normal speech organs, and occlusion, and no hearing or cognitive impairments (ie, no cognition disorders). Assessment employed the Chinese Standard Mandarin speech intelligibility scale, an alveolar sound (/s/, /ts'/, /ts/) clarity scale, the PRAAT speech workstation, and a soundproof booth equipped with a professional noise-shielding sound card and microphone. Three experienced speech therapists independently evaluated error rates and error types for each alveolar sound (/s/, /ts'/, /ts/) by different ethnic groups and ages, and they also recorded intervention duration. Error articulation patterns included omission (deletion), weakening, and various compensatory articulations. The highest error rate was found in /ts/, predominantly omission (67.65%, 46/68). Next, /s/ showed mainly omission and lateralization errors, whereas /ts'/ was primarily characterized by weakening. There was no significant difference (P>0.05) in the incidence of alveolar sound articulation errors among different ethnic groups. Spectrogram analysis objectively confirmed whether the error type involved omission, weakening, or substitution. During treatment, three types of visual biofeedback were used as intervention methods, achieving favorable therapeutic outcomes. All patients were treated for 4 to 6 weeks, resulting in complete recovery in 63 cases and improvement in 5 cases; 0 cases showed no improvement. Among postoperative palatoplasty patients with good velopharyngeal function, alveolar affricates (/ts/) show the highest error rates in both Han and ethnic minority patients. Providing targeted foundational training before inducing the target sound and utilizing three visual biofeedback interventions in rotation yields optimal results. The third biofeedback approach showed particularly high acceptance among patients, making it especially suitable for remote therapy.