Relevance of the Implementation of Teeth in Three-Dimensional Vocal Tract Models Purpose Recently, efforts have been made to investigate the vocal tract using magnetic resonance imaging (MRI). Due to technical limitations, teeth were omitted in many previous studies on vocal tract acoustics. However, the knowledge of how teeth influence vocal tract acoustics might be important in order to estimate the necessity ... Research Article
Research Article  |   September 18, 2017
Relevance of the Implementation of Teeth in Three-Dimensional Vocal Tract Models
 
Author Affiliations & Notes
  • Louisa Traser
    Institute of Musicians' Medicine, Freiburg University Medical Center, Germany
    Department of Otolaryngology, Freiburg University Medical Center, Germany
    Faculty of Medicine, University of Freiburg, Germany
  • Peter Birkholz
    Institute of Acoustics and Speech Communication, Technische Universität, Dresden, Germany
  • Tabea Viktoria Flügge
    Faculty of Medicine, University of Freiburg, Germany
    Department of Craniomaxillofacial Surgery, Freiburg University Medical Center, Germany
  • Robert Kamberger
    Laboratory of Simulation, Department of Microsystems Engineering–IMTEK, University of Freiburg, Germany
  • Michael Burdumy
    Faculty of Medicine, University of Freiburg, Germany
    Department of Medical Physics, Radiology, Freiburg University Medical Center, Germany
  • Bernhard Richter
    Institute of Musicians' Medicine, Freiburg University Medical Center, Germany
    Faculty of Medicine, University of Freiburg, Germany
  • Jan Gerrit Korvink
    Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
  • Matthias Echternach
    Institute of Musicians' Medicine, Freiburg University Medical Center, Germany
    Faculty of Medicine, University of Freiburg, Germany
  • Disclosure: The authors have declared that no competing interests existed at the time of publication.
    Disclosure: The authors have declared that no competing interests existed at the time of publication. ×
  • Correspondence to Louisa Traser: louisa.traser@uniklinik-freiburg.de
  • Editor: Julie Liss
    Editor: Julie Liss×
  • Associate Editor: Jack Jiang
    Associate Editor: Jack Jiang×
Article Information
Speech, Voice & Prosody / Speech / Research Articles
Research Article   |   September 18, 2017
Relevance of the Implementation of Teeth in Three-Dimensional Vocal Tract Models
Journal of Speech, Language, and Hearing Research, September 2017, Vol. 60, 2379-2393. doi:10.1044/2017_JSLHR-S-16-0395
History: Received October 10, 2016 , Revised February 14, 2017 , Accepted February 23, 2017
 
Journal of Speech, Language, and Hearing Research, September 2017, Vol. 60, 2379-2393. doi:10.1044/2017_JSLHR-S-16-0395
History: Received October 10, 2016; Revised February 14, 2017; Accepted February 23, 2017

Purpose Recently, efforts have been made to investigate the vocal tract using magnetic resonance imaging (MRI). Due to technical limitations, teeth were omitted in many previous studies on vocal tract acoustics. However, the knowledge of how teeth influence vocal tract acoustics might be important in order to estimate the necessity of implementing teeth in vocal tract models. The aim of this study was therefore to estimate the effect of teeth on vocal tract acoustics.

Method The acoustic properties of 18 solid (3-dimensional printed) vocal tract models without teeth were compared to the same 18 models including teeth in terms of resonance frequencies (f Rn). The f Rn were obtained from the transfer functions of these models excited by white noise at the glottis level. The models were derived from MRI data of 2 trained singers performing 3 different vowel conditions (/i/, /a/, and /u/) in speech and low-pitched and high-pitched singing.

Results Depending on the oral configuration, models exhibiting side cavities or side branches were characterized by major changes in the transfer function when teeth were implemented via the introduction of pole-zero pairs.

Conclusions To avoid errors in modeling, teeth should be included in 3-dimensional vocal tract models for acoustic evaluation.

Supplemental Material https://doi.org/10.23641/asha.5386771

Acknowledgments
The authors thank Horst Urbach and Hansjörg Mast for assistance in MRI measurements, Marc Metzger for his help in the implementation of teeth, Manfred Nusseck for his help in statistical evaluation, Stefan Zirn and Thomas Wesarg for their help in the experimental setup and the provision of the sound-treated room, and Jude Brereton for native corrections. Matthias Echternach's and Bernhard Richter's work is supported by the Deutsche Forschungsgemeinschaft (DFG), Grant EC 409/1-2 and RI 1050/4-3. Part of the material was presented at the 9th International Conference on Voice Physiology and Biomechanics on April 10, 2014 in Salt Lake City, UT.
Order a Subscription
Pay Per View
Entire Journal of Speech, Language, and Hearing Research content & archive
24-hour access
This Article
24-hour access