Changes of some functional speech disorders after surgical correction of skeletal anterior open bite

Impact of orthognathic surgery on voice and speech: a systematic review and meta-analysis

BACKGROUND

Orthognathic surgical procedures, whether in one or both jaws, can affect structures regarding the articulation and resonance of voice and speech.

OBJECTIVE

Evaluating the impact of orthognathic surgery on voice and speech performance in individuals with skeletal dentofacial disharmony.

SEARCH METHODS

Word combinations and truncations were adapted for the following electronic databases: EMBASE, PubMed/Medline, Scopus, Web of Science, Cochrane Library, and Latin American and Caribbean Literature in Health Sciences (LILACS), and grey literature.

SELECTION CRITERIA

The research included studies on nonsyndromic adults with skeletal dentofacial disharmony undergoing orthognathic surgery. These studies assessed patients before and after surgery or compared them with individuals with good facial harmony using voice and speech parameters through validated protocols.

DATA COLLECTION AND ANALYSIS

Two independent reviewers performed all stages of the review. The Joanna Briggs Institute tool was used to assess risk of bias in the cohort studies, and ROBINS-I was used for nonrandomized clinical trials. The authors also performed a meta-analysis of random effects.

RESULTS

A total of 1163 articles were retrieved after the last search, of which 23 were read in full. Of these, four were excluded, totalling 19 articles for quantitative synthesis. When comparing the pre- and postoperative periods, both for fundamental frequency, formants, and jitter and shimmer perturbation measures, orthognathic surgery did not affect vowel production. According to the articles, the main articulatory errors associated with skeletal dentofacial disharmonies prior to surgery were distortions of fricative sounds, mainly/s/ and/z/.

CONCLUSIONS

Orthognathic surgery may have little or no impact on vocal characteristics during vowel production. However, due to the confounding factors involved, estimates are inconclusive. The most prevalent articulatory disorders in the preoperative period were distortion of the fricative phonemes/s/ and/z/. However, further studies must be carried out to ensure greater robustness to these findings.

REGISTRATION

PROSPERO (CRD42022291113).

Impacts of Development, Dentofacial Disharmony, and Its Surgical Correction on Speech: A Narrative Review for Dental Professionals

Speech is a communication method found only in humans that relies on precisely articulated sounds to encode and express thoughts. Anatomical differences in the maxilla, mandible, tooth position, and vocal tract affect tongue placement and broadly influence the patterns of airflow and resonance during speech production. Alterations in these structures can create perceptual distortions in speech known as speech sound disorders (SSDs). As craniofacial development occurs, the vocal tract, jaws, and teeth change in parallel with stages of speech development, from babbling to adult phonation. Alterations from a normal Class 1 dental and skeletal relationship can impact speech. Dentofacial disharmony (DFD) patients have jaw disproportions, with a high prevalence of SSDs, where the severity of malocclusion correlates with the degree of speech distortion. DFD patients often seek orthodontic and orthognathic surgical treatment, but there is limited familiarity among dental providers on the impacts of malocclusion and its correction on speech. We sought to review the interplay between craniofacial and speech development and the impacts of orthodontic and surgical treatment on speech. Shared knowledge can facilitate collaborations between dental specialists and speech pathologists for the proper diagnosis, referral, and treatment of DFD patients with speech pathologies.

Vowel sound production and its association with cephalometric characteristics in skeletal Class III subjects

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.

Relationship Between Oropharyngeal Geometry and Acoustic Parameters in Singers: A Preliminary Study

OBJECTIVE

To verify possible correlations between formant and cepstral parameters and oropharyngeal geometry in singers, stratified by sex.

METHOD

Voice records and oropharyngeal measures of 31 singers - 13 females and 18 males, mean age of 28 (±5.0) years - were retrieved from a database and analyzed. The oropharyngeal geometry measures were collected with acoustic pharyngometry, and the voice records consisted of sustained vowel /Ԑ/ phonation, which were exported to Praat software and edited to obtain the formant and cepstral parameters, stratified by sex. The Pearson linear correlation test was applied to relate voice parameters to oropharyngeal geometry, at the 5% significance level; the linear regression test was used to justify the variable related to the second formant.

RESULTS

Differences between the sexes were identified only in the oral cavity length (greater in males) and pharyngeal cavity length (greater in females). There was a linear correlation between the third formant and the cepstrum in the female group. In the male group, there was a linear correlation between the cepstrum and the third and fourth formants. A positive linear correlation with up to 95% confidence was also identified between the pharyngeal cavity volume and the second formant in the female group, making it possible to estimate a regression model for the second formant (R2 = 0.70).

CONCLUSION

There are correlations between the oropharyngeal geometry and formant and cepstral parameters in relation to sex. The pharyngeal cavity volume showed the greatest correlation between females and the second formant.

Análise das medidas eletroglotográficas da voz: padrões de normalidade para cantores por meio do programa CSL da Kay Pentax®

RESUMO Objetivo: Analisar as medidas de frequência fundamental, jitter eletroglotográfico, quociente de contato e periodicidade das ondas eletroglotográficas da voz de cantores em registro modal. Método: Estudo observacional de corte transversal que selecionou indivíduos de escolas de canto da região central do município de Belo Horizonte-MG. A amostra foi não probabilística, por conveniência, composta por 60 indivíduos cantores com faixa etária entre 18 e 55 anos, sendo 30 homens e 30 mulheres. Para a coleta do registro eletroglotográfico, foi utilizado o programa CSL da Kay Pentax™, model 6103, módulo Electroglottography. Os participantes foram posicionados sentados e, após a higienização da pele do pescoço com álcool 70 %, dois eletrodos foram colocados nas alas da cartilagem tireóidea no nível das pregas vocais. Posteriormente, os participantes foram orientados a emitir a vogal /a/ sustentada de forma habitual. Foram analisadas as medidas de frequência fundamental (f0), quociente de contato (QC), jitter eletroglotográfico e periodicidade da onda eletroglotográfica. Os dados foram analisados estatisticamente utilizando o Minitab 17. Resultados: Os parâmetros analisados foram estatisticamente significantes. A frequência fundamental (f0) foi maior nas mulheres (226,91 Hz) quando comparada com a dos homens (166,54 Hz). As medidas de quociente de contato e de periodicidade também foram maiores nas mulheres (40,46 % e 15,51 %, respectivamente) se comparadas às dos homens (27,45 % e 7,82, respectivamente). O parâmetro de jitter foi maior nos homens, quando comparado ao das mulheres. Conclusão: Os valores de frequência fundamental (f0), quociente de contato (QC) e periodicidade da onda foram maiores nas mulheres. O valor de jitter foi maior nos homens.

Using Innovative Acoustic Analysis to Predict the Postoperative Outcomes of Unilateral Vocal Fold Paralysis

Objective. Autologous fat injection laryngoplasty is ineffective for some patients with iatrogenic vocal fold paralysis, and additional laryngeal framework surgery is often required. An acoustically measurable outcome predictor for lipoinjection laryngoplasty would assist phonosurgeons in formulating treatment strategies. Methods. Seventeen thyroid surgery patients with unilateral vocal fold paralysis participated in this study. All subjects underwent lipoinjection laryngoplasty to treat postsurgery vocal hoarseness. After treatment, patients were assigned to success and failure groups on the basis of voice improvement. Linear prediction analysis was used to construct a new voice quality indicator, the number of irregular peaks (NIrrP). It compared with the measures used in the Multi-Dimensional Voice Program (MDVP), such as jitter (frequency perturbation) and shimmer (perturbation of amplitude). Results. By comparing the [i] vowel produced by patients before the lipoinjection laryngoplasty (AUC = 0.98, 95% CI = 0.78–0.99), NIrrP was shown to be a more accurate predictor of long-term surgical outcomes than jitter (AUC = 0.73, 95% CI = 0.47–0.91) and shimmer (AUC = 0.63, 95% CI = 0.37–0.85), as identified by the receiver operating characteristic curve. Conclusions. NIrrP measured using the LP model could be a more accurate outcome predictor than the parameters used in the MDVP.