Computer analysis of acoustic features of consonants before and after restoration with complete denture
- VernacularTitle:计算机语音分析系统对全口义齿初戴前后辅音的声学分析
- Author:
Jun LI
;
Fuqiang ZHANG
;
Yang CHEN
;
Guomin WANG
- Publication Type:Journal Article
- From:
Chinese Journal of Tissue Engineering Research
2005;9(46):173-175
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND: Traditional acoustic examination is to make subjective descriptions of abnormal acoustic features, or carry out quantitative analysis of vowels with sensitive consonant utterance only subjected to qualitative analysis.OBJECTIVE: To make quantitative analysis of the acoustic features of sensitive consonants before and after restoration with complete denture. DESIGN: Randomized controlled experiment.SETTING: Department of Prosthodontics; Department of Oral & Maxillofacial Surgery, Ninth People's Hospital of Shanghai Second Medical University.PARTICIPANTS: Totally 30 edentulous patients who received treatment in the Department of Prosthodontics, Ninth People's Hospital of Shanghai Second Medical University, between November 2001 and March 2003-03were enrolled in this study. They were divided into plastic base group and metal base group with 15 patients in each group according to the denture base; the two groups of patients were matched in baseline data such as sex and age. Inclusion criteria: had no history of denture repairing, aged 45-75years, had received certain years of education, could speak Mandarin with out obvious dialect, had no obvious dysaudia (≤ 20dB), and had not received acoustic therapeutic training.METHODS: Plastic base group: the plastic base was 2.0-2.5 mm thick,with smooth anterior palate polished surface. Metal base group: the metal base was 1.0-1.5 mm thick, covering entire palate and forming palatal rugae, which transformed to net base at alveolar ridge side, and cheek base was plastic. The scope of base, the posterior bank of denture, overbite of anterior teeth, coverage degree, occlusal surface and 1/3 vertical range beneath surface were designed conventionally. Utterance of/zi/ and/ji/ by edentulous patients was detected before restoration, at the beginning and after restoration 1, 2, 4, 8 weeks respectively, with the results analyzed with the assistance of computer acoustic analysis system, the linear forecast technology and fast Fourier transformation were used to record the 1st and 3rdformants, the computer acoustic analytic sampling frequency was 10 000 Hz and he step number of linear forecast technology was 12.MAIN OUTCOME MEASURES: The differences in acoustic parameters between the detected utterances/zi/and/ji/.RESULTS: According to the intention-to-treat analysis, 30 patients were enrolled in this experiment and all of them entered the result analysis. ①When utterance/zi/was detected, most of 1st formants were found gradually reduced in plastic base group and metal base group after restoration compared to that before restoration, most obviously at week 8 [(353.67±35.65),(322.60±44.03); (332.27±37.10), (302.20±40.39); P ＜ 0.05]. However,the 3rd formant variance was different between the two groups, presented by gradually ascending in plastic base group and gradually descending in metal base group. ② When the detected utterance was/ci/, changes of the 1st formants in two groups were basically the same as /zi/; moreover the changes of the 3rd formants also displayed different tendency in the two groups.CONCLUSION: Reducing the basal thickness of complete denture and reconstructing palatal rugae will be helpful for the acoustic functional restoration in patients with dentition defects. The computer acoustic analysis system can be used for quantitative analysis of acoustic features of patients before and after restoration with complete denture.
