Acoustic Measurements of Speech and Voice in Men with Angle Class II, Division 1, Malocclusion.

 The acoustic analysis of speech (measurements of the fundamental frequency and formant frequencies) of different vowels produced by speakers with the Angle class II, division 1, malocclusion can provide information about the relationship between articulatory and phonatory mechanisms in this type of maxillomandibular disproportion.  To investigate acoustic measurements related to the fundamental frequency (F0) and formant frequencies (F1 and F2) of the oral vowels of Brazilian Portuguese (BP) produced by male speakers with Angle class II, division 1, malocclusion (study group) and compare with men with Angle class I malocclusion (control group).  In total, 60 men (20 with class II, 40 with class I) aged between 18 and 40 years were included in the study.

Acoustic Analysis of Voice and Speech in Men with Skeletal Class III Malocclusion: A Pilot Study.

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.

Frequency measurement of vowel formants produced by Brazilian children aged between 4 and 8 years.

Objective: To investigate frequency measurement of the first three formants of the seven oral Brazilian Portuguese vowels of healthy children aged 4-8 years.

Methods: Two hundred seven children of both genders were selected by oral expression screening and perceptive-auditory analysis. They were separated into four age groups (G1, G2, G3, and G4) and by gender.