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Zhou C, Duan P, He H, Song J, Hu M, Liu Y, Liu Y, Guo J, Jin F, Cao Y, Jiang L, Ye Q, Zhu M, Jiang B, Ruan W, Yuan X, Li H, Zou R, Tian Y, Gao L, Shu R, Chen J, Liu R, Zou S, Li X. Expert consensus on pediatric orthodontic therapies of malocclusions in children. Int J Oral Sci 2024; 16:32. [PMID: 38627388 PMCID: PMC11021504 DOI: 10.1038/s41368-024-00299-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/08/2024] [Accepted: 04/03/2024] [Indexed: 04/19/2024] Open
Abstract
Malocclusion, identified by the World Health Organization (WHO) as one of three major oral diseases, profoundly impacts the dental-maxillofacial functions, facial esthetics, and long-term development of ~260 million children in China. Beyond its physical manifestations, malocclusion also significantly influences the psycho-social well-being of these children. Timely intervention in malocclusion can foster an environment conducive to dental-maxillofacial development and substantially decrease the incidence of malocclusion or reduce the severity and complexity of malocclusion in the permanent dentition, by mitigating the negative impact of abnormal environmental influences on the growth. Early orthodontic treatment encompasses accurate identification and treatment of dental and maxillofacial morphological and functional abnormalities during various stages of dental-maxillofacial development, ranging from fetal stages to the early permanent dentition phase. From an economic and societal standpoint, the urgency for effective early orthodontic treatments for malocclusions in childhood cannot be overstated, underlining its profound practical and social importance. This consensus paper discusses the characteristics and the detrimental effects of malocclusion in children, emphasizing critical need for early treatment. It elaborates on corresponding core principles and fundamental approaches in early orthodontics, proposing comprehensive guidance for preventive and interceptive orthodontic treatment, serving as a reference for clinicians engaged in early orthodontic treatment.
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Affiliation(s)
- Chenchen Zhou
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Peipei Duan
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Hong He
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration & Key Laboratory of Oral Biomedicine Ministry of Education & Hubei Key Laboratory of Stomatology & Department of Orthodontics & Center for Dentofacial Development and Sleep Medicine, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Jinlin Song
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences & Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Stomatological Hospital of Chongqing Medical University, Chongqing Medical University & College of Stomatology, Chongqing Medical University, Chongqing, China
| | - Min Hu
- Department of Orthodontics, Hospital of Stomatology, Jilin University, Changchun, China
| | - Yuehua Liu
- Department of Orthodontic & Oral Biomedical Engineering Laboratory, Shanghai Stomatological Hospital, Fudan University, Shanghai, China
| | - Yan Liu
- Department of Orthodontics, Central Laboratory, Peking University School and Hospital for Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology & Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health & NMPA Key Laboratory for Dental Materials & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
| | - Jie Guo
- Department of Orthodontics, School and Hospital of Stomatology, College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration & Shandong Provincial Clinical Research Center for Oral Diseases, Shandong University, Jinan, China
| | - Fang Jin
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, Air Force Medical University, Xi'an, China
| | - Yang Cao
- Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, China
| | - Lingyong Jiang
- Center of Craniofacial Orthodontics, Department of Oral and Cranio-Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine & College of Stomatology, Shanghai Jiao Tong University & National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai Research Institute of Stomatology, Shanghai, China
| | - Qingsong Ye
- Center of Regenerative Medicine, Department of Stomatology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Min Zhu
- Department of Oral and Cranio-maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine & National Clinical Research Center for Oral Diseases & Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, China
| | - Beizhan Jiang
- Department of Pediatric Dentistry, School and Hospital of Stomatology, Tongji University & Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, China
| | - Wenhua Ruan
- Department of Stomatology, The Children's Hospital, Zhejiang University School of Medicine & National Clinic Research Center for Child Health, Hangzhou, China
| | - Xiao Yuan
- Department of Orthodontics, The Affiliated Hospital of & School of Stomatology, Qingdao University, Qingdao, China
| | - Huang Li
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
| | - Rui Zou
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases & College of Stomatology, Xi'an Jiaotong University & Department of Orthodontics, Xi'an Jiaotong University, Xi'an, China
| | - Yulou Tian
- Department of Orthodontics, School and Hospital of Stomatology, China Medical University & Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China
| | - Li Gao
- Department of Pediatric Dentistry, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Rui Shu
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jianwei Chen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Renkai Liu
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Shujuan Zou
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
| | - Xiaobing Li
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
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Vorperian HK, Kent RD, Lee Y, Buhr KA. Vowel Production in Children and Adults With Down Syndrome: Fundamental and Formant Frequencies of the Corner Vowels. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2023; 66:1208-1239. [PMID: 37015000 PMCID: PMC10187968 DOI: 10.1044/2022_jslhr-22-00510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 12/01/2022] [Accepted: 12/21/2022] [Indexed: 05/18/2023]
Abstract
PURPOSE Atypical vowel production contributes to reduced speech intelligibility in children and adults with Down syndrome (DS). This study compares the acoustic data of the corner vowels /i/, /u/, /æ/, and /ɑ/ from speakers with DS against typically developing/developed (TD) speakers. METHOD Measurements of the fundamental frequency (f o) and first four formant frequencies (F1-F4) were obtained from single word recordings containing the target vowels from 81 participants with DS (ages 3-54 years) and 293 TD speakers (ages 4-92 years), all native speakers of English. The data were used to construct developmental trajectories and to determine interspeaker and intraspeaker variability. RESULTS Trajectories for DS differed from TD based on age and sex, but the groups were similar with the striking change in f o and F1-F4 frequencies around age 10 years. Findings confirm higher f o in DS, and vowel-specific differences between DS and TD in F1 and F2 frequencies, but not F3 and F4. The measure of F2 differences of front-versus-back vowels was more sensitive of compression than reduced vowel space area/centralization across age and sex. Low vowels had more pronounced F2 compression as related to reduced speech intelligibility. Intraspeaker variability was significantly greater for DS than TD for nearly all frequency values across age. DISCUSSION Vowel production differences between DS and TD are age- and sex-specific, which helps explain contradictory results in previous studies. Increased intraspeaker variability across age in DS confirms the presence of a persisting motor speech disorder. Atypical vowel production in DS is common and related to dysmorphology, delayed development, and disordered motor control.
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Affiliation(s)
- Houri K. Vorperian
- Vocal Tract Development Lab, Waisman Center, University of Wisconsin–Madison
| | - Raymond D. Kent
- Vocal Tract Development Lab, Waisman Center, University of Wisconsin–Madison
| | - Yen Lee
- Department of Educational Leadership, Edgewood College, Madison, Wisconsin
| | - Kevin A. Buhr
- Department of Biostatistics and Medical Informatics, University of Wisconsin–Madison
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Pravitharangul N, Miyamoto JJ, Yoshizawa H, Matsumoto T, Suzuki S, Chantarawaratit PO, Moriyama K. Vowel sound production and its association with cephalometric characteristics in skeletal Class III subjects. Eur J Orthod 2023; 45:20-28. [PMID: 35731636 DOI: 10.1093/ejo/cjac031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND This study aimed to evaluate differences in vowel production using acoustic analysis in skeletal Class III and Class I Japanese participants and to identify the correlation between vowel sounds and cephalometric variables in skeletal Class III subjects. MATERIALS AND METHODS Japanese males with skeletal Class III (ANB < 0°) and Class I skeletal anatomy (0.62° < ANB < 5.94°) were recruited (n = 18/group). Acoustic analysis of vowel sounds and cephalometric analysis of lateral cephalograms were performed. For sound analysis, an isolated Japanese vowel (/a/,/i/,/u/,/e/,/o/) pattern was recorded. Praat software was used to extract acoustic parameters such as fundamental frequency (F0) and the first four formants (F1, F2, F3, and F4). The formant graph area was calculated. Cephalometric values were obtained using ImageJ. Correlations between acoustic and cephalometric variables in skeletal Class III subjects were then investigated. RESULTS Skeletal Class III subjects exhibited significantly higher/o/F2 and lower/o/F4 values. Mandibular length, SNB, and overjet of Class III subjects were moderately negatively correlated with acoustic variables. LIMITATIONS This study did not take into account vertical skeletal patterns and tissue movements during sound production. CONCLUSION Skeletal Class III males produced different /o/ (back and rounded vowel), possibly owing to their anatomical positions or adaptive changes. Vowel production was moderately associated with cephalometric characteristics of Class III subjects. Thus, changes in speech after orthognathic surgery may be expected. A multidisciplinary team approach that included the input of a speech pathologist would be useful.
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Affiliation(s)
- Natthaporn Pravitharangul
- Department of Maxillofacial Orthognathics, Division of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Japan.,Department of Orthodontics, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.,Tokyo Medical and Dental University and Chulalongkorn University International Joint Degree Doctor of Philosophy Program in Orthodontics
| | - Jun J Miyamoto
- Department of Maxillofacial Orthognathics, Division of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Japan
| | - Hideyuki Yoshizawa
- Department of Maxillofacial Orthognathics, Division of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Japan
| | - Tsutomu Matsumoto
- Department of Maxillofacial Orthognathics, Division of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Japan
| | - Shoichi Suzuki
- Department of Maxillofacial Orthognathics, Division of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Japan
| | | | - Keiji Moriyama
- Department of Maxillofacial Orthognathics, Division of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Japan
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Kent RD, Rountrey C. What Acoustic Studies Tell Us About Vowels in Developing and Disordered Speech. AMERICAN JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2020; 29:1749-1778. [PMID: 32631070 PMCID: PMC7893529 DOI: 10.1044/2020_ajslp-19-00178] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 11/04/2019] [Accepted: 04/19/2020] [Indexed: 05/05/2023]
Abstract
Purpose Literature was reviewed on the development of vowels in children's speech and on vowel disorders in children and adults, with an emphasis on studies using acoustic methods. Method Searches were conducted with PubMed/MEDLINE, Google Scholar, CINAHL, HighWire Press, and legacy sources in retrieved articles. The primary search items included, but were not limited to, vowels, vowel development, vowel disorders, vowel formants, vowel therapy, vowel inherent spectral change, speech rhythm, and prosody. Results/Discussion The main conclusions reached in this review are that vowels are (a) important to speech intelligibility; (b) intrinsically dynamic; (c) refined in both perceptual and productive aspects beyond the age typically given for their phonetic mastery; (d) produced to compensate for articulatory and auditory perturbations; (e) influenced by language and dialect even in early childhood; (f) affected by a variety of speech, language, and hearing disorders in children and adults; (g) inadequately assessed by standardized articulation tests; and (h) characterized by at least three factors-articulatory configuration, extrinsic and intrinsic regulation of duration, and role in speech rhythm and prosody. Also discussed are stages in typical vowel ontogeny, acoustic characterization of rhotic vowels, a sensory-motor perspective on vowel production, and implications for clinical assessment of vowels.
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Affiliation(s)
- Ray D. Kent
- Waisman Center, University of Wisconsin–Madison
| | - Carrie Rountrey
- Department of Communication Sciences and Disorders, University of Cincinnati, OH
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Viegas F, Viegas D, Serra Guimarães G, Ritto F, Simões-Zenari M, Nemr K. Acoustic Analysis of Voice and Speech in Men with Skeletal Class III Malocclusion: A Pilot Study. Folia Phoniatr Logop 2020; 73:117-125. [PMID: 32036357 DOI: 10.1159/000505186] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 12/01/2019] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES To assess the fundamental (f0) and first third formant (F1, F2, F3) frequencies of the 7 oral vowels of Brazilian Portuguese in men with skeletal class III malocclusion and to compare these measures with a control group of individuals with Angle's class I. METHODS Sixty men aged 18-40 years, 20 with Angle's class III skeletal malocclusion and 40 with Angle's class I malocclusion were selected by speech therapists and dentists. The speech signals were obtained from sustained vowels, and the values of f0 and frequencies of F1, F2 and F3 were estimated. The differences were verified through Student's t test, and the effect size calculation was performed. RESULTS In the class III group, more acute f0 values were observed in all vowels, higher values of F1 in the vowels [a] and [ε] and in F2 in the vowels [a], [e] and [i] and lower F1 and F3 values of the vowel [u]. CONCLUSION More acute f0 values were found in all vowels investigated in the class III group, which showed a higher laryngeal position in the production of these sounds. The frequencies of the first 3 formants showed punctual differences, with higher values of F1 in the vowels [a] and [ε] and of F2 in [a], [e] and [i], and lower values of F1 and F3 in the vowel [u] in the experimental group. Thus, it is concluded that the fundamental frequency of the voice was the main parameter that differentiated the studied group from the control.
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Affiliation(s)
- Flávia Viegas
- Department of Physical Therapy, Speech and Hearing Therapy and Occupational Therapy, University of São Paulo, São Paulo, Brazil, .,Department of Specific Training in Speech and Hearing Pathology, Federal Fluminense University, Rio de Janeiro, Brazil,
| | | | - Glaucio Serra Guimarães
- Department of Specific Training (Dentistry), Federal Fluminense University, Rio de Janeiro, Brazil
| | - Fabio Ritto
- Pedro Ernesto University Hospital, Rio de Janeiro State University, Rio de Janeiro, Brazil
| | - Marcia Simões-Zenari
- Department of Physical Therapy, Speech and Hearing Therapy and Occupational Therapy, University of São Paulo, São Paulo, Brazil
| | - Katia Nemr
- Department of Physical Therapy, Speech and Hearing Therapy and Occupational Therapy, University of São Paulo, São Paulo, Brazil
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Kent RD, Vorperian HK. Static measurements of vowel formant frequencies and bandwidths: A review. JOURNAL OF COMMUNICATION DISORDERS 2018; 74:74-97. [PMID: 29891085 PMCID: PMC6002811 DOI: 10.1016/j.jcomdis.2018.05.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 04/23/2018] [Accepted: 05/27/2018] [Indexed: 05/05/2023]
Abstract
PURPOSE Data on vowel formants have been derived primarily from static measures representing an assumed steady state. This review summarizes data on formant frequencies and bandwidths for American English and also addresses (a) sources of variability (focusing on speech sample and time sampling point), and (b) methods of data reduction such as vowel area and dispersion. METHOD Searches were conducted with CINAHL, Google Scholar, MEDLINE/PubMed, SCOPUS, and other online sources including legacy articles and references. The primary search items were vowels, vowel space area, vowel dispersion, formants, formant frequency, and formant bandwidth. RESULTS Data on formant frequencies and bandwidths are available for both sexes over the lifespan, but considerable variability in results across studies affects even features of the basic vowel quadrilateral. Origins of variability likely include differences in speech sample and time sampling point. The data reveal the emergence of sex differences by 4 years of age, maturational reductions in formant bandwidth, and decreased formant frequencies with advancing age in some persons. It appears that a combination of methods of data reduction provide for optimal data interpretation. CONCLUSION The lifespan database on vowel formants shows considerable variability within specific age-sex groups, pointing to the need for standardized procedures.
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Affiliation(s)
- Raymond D Kent
- Waisman Center, University of Wisconsin-Madison, United States.
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Abstract
PURPOSE To analyze the speech articulatory characteristics of individuals with dentofacial deformities (DFD) and assess differences compared to individuals with dentofacial balance. METHODS Sixty individuals participated, being 30 presenting DFD (19 with class III and 11 class II skeletal malocclusion, 18 women and 12 men, age group 18-40 years) and 30 individuals from a control group matched for gender and age. The assessment of the diadochokinesis (DDK) was evaluated using the emissions /pa/, /ta/, /ka/, /pataka/, and /i/. RESULTS The individuals with DFD produced fewer emissions per second: at syllable "ka" and sequence "pataka" for the total of individuals; syllable "pa" and sequence "pataka" for women, individuals with class II and class III malocclusion. The parameters related to the irregularity of the cycles were higher for the group with DFD than for the control, as well as emission of the syllable "pa" for the total of individuals, group of class III malocclusion and women, during production of the syllables "ta" and "ka" for all individuals and group of class III and during emission of the vowel "ï" for women. CONCLUSIONS Differences regarding speed and stability of oral and laryngeal DDK were found among individuals with DFD compared with the control group.
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Yan N, Ng ML, Man MK, To TH. Vocal tract dimensional characteristics of professional male and female singers with different types of singing voices. INTERNATIONAL JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2013; 15:484-491. [PMID: 23391478 DOI: 10.3109/17549507.2012.744429] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The present study examined the possible relationship between classification of professional singing voices and their vocal tract parameters including vocal tract length and volume, and vowel formant frequencies. Acoustic reflection technology (ART) was used to measure vocal tract length and volume of 107 professional singers: 32 tenors, 25 baritones, 27 sopranos, and 23 mezzo-sopranos. The first three formant frequencies (F1-F3) of the English vowels /a, æ, i/ produced by the professional singers were also obtained. Results indicated significantly shorter oral and vocal tract length, and smaller oral and vocal tract volume associated with sopranos when compared with mezzo-sopranos. Acoustically, sopranos had higher F1, F2, and F3 values than mezzo-sopranos. The present findings suggest that, in addition to vocal tract length, vocal tract volume may also affect formant frequencies, implying the possibility that classifying professional singing voices is based on both vocal tract length and volume information.
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Affiliation(s)
- Nan Yan
- Ambient Intelligence and Multimodal Systems Lab, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences , Shenzhen , PR China
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Flipsen P, Lee S. Reference data for the American English acoustic vowel space. CLINICAL LINGUISTICS & PHONETICS 2012; 26:926-33. [PMID: 23057793 DOI: 10.3109/02699206.2012.720634] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Reference data for the acoustic vowel space area (VSA) in children and adolescents do not currently appear to be available in a form suitable for normative comparisons. In the current study, individual speaker formant data for the four corner vowels of American English (/i, u, æ, ɑ/) were used to compute individual speaker VSAs. The sample included 300 children aged 5-18 years and 38 adults aged 25-50 years. Age trends and sex differences were examined and reference data for clinical application were developed. Findings indicated significant declines in VSA with age; sex differences were not fully apparent until late adolescence and adulthood. Implications are discussed.
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Affiliation(s)
- Peter Flipsen
- Department of Communication Sciences and Disorders, Idaho State University, ID 83642, USA.
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