Acoustic Comparison of Vowel Sounds Produced Before and After Orthognathic Surgery for Mandibular Advancement

Acoustic analysis of vowel sounds before and after orthognathic surgery

“…No significant changes were found in the mandibular advancement study 30 weeks after the surgery (Niemi et al, 2006). The advancement of the mandible only stretched the vocal tract, which caused temporary changes in articulation, as it did not interfere with the movement of the tongue.…”

“…Other researchers, such as Niemi et al (2006), considered this phenomenon to reflect individual changes in the motionadjustment stage, arguing that the operation itself does not influence the resonance of the vocal cords. Instead, as the patients themselves recognise the changes in the vocal tract, they compensate in their articulation so that any pre-existing phonetic articulation is modified or replaced after surgery.…”

“…Their study also did not provide guidelines regarding how to actually perform orthognathic surgery (Bowers et al, 1985). Using formant analysis, Niemi et al analysed vowel changes by measuring F0, F1, and F2 values and studied samples of five class II malocclusion patients (one of whom also simultaneously underwent a Le Fort I osteotomy) who underwent BSSRO (Niemi et al, 2006). Each of these five patients showed visible changes in a formant graph.…”

Recording Speech Sound and Articulation in Mri

“…When soft tissue and muscle models are incorporated, we expect that such a simulator is useful for studying speech production from a wider phonetics point of view, and planning and evaluating oral and maxillofacial surgery (Dedouch, Horáček, Vampola, &Černý, 2002;Nishimoto, Akagi, Kitamura, & Suzuki, 2004;Švancara & Horáček, 2006). See also Vahatalo, Laaksonen, Tamminen, Aaltonen, and Happonen (2005) and Niemi, Laaksonen, Peltomaki, Kurimo, Aaltonen, and Happonen (2006) for background.…”

Standardization of Thresholding for Binary Conversion of Vocal Tract Modeling in Computed Tomography

“…1 Because the patients' quality of life depends heavily on the recovery of speech ability, 2 it is important for medical practitioners to investigate methods of reproducing the detailed shapes and acoustic characteristics of their vocal tracts. 3 Modern imaging techniques are now being used to acquire three-dimensional (3-D) shape information about the vocal tract volume and associated airways. One technique is magnetic resonance imaging (MRI) and the other is X-ray computed tomography (CT).…”