title: Developing a new appliance to dissipate mechanical load on teeth and improve limitation of vertical mouth.
abstract: OBJECTIVE
  The principle of leverage to superpose the convex surfaces of two shells was applied to develop a device for treating limitation of mouth opening and called it the "shell-shaped mouth opener" and analyzed pressure on the teeth with the TheraBite(®) appliance and the shell-shaped mouth opening appliance.
  
  
  METHODS
  To compare the TheraBite(®) appliance and the shell-shaped mouth opening appliance, pressure on the teeth in the dentition model with both devices was analyzed using the Inastomer(®) flexible conductive sensor.
  
  
  RESULTS
  The load was better dispersed to each tooth in the shell-shaped mouth opening appliance in the all quadrants compared to the TheraBite(®) appliance.
  
  
  CONCLUSIONS
  The present study revealed that the shell-shaped mouth opening appliance which was originally invented in our lab, dissipated the mechanical load on teeth more evenly than the TheraBite(®) appliance.
authors.affiliation: Department of Dentistry, Oral and Maxillofacial Plastic and Reconstructive Surgery, Yamagata Japan. ; The first two authors contributed equally to this work.
authors.forename: Takashi
authors.initials: T
authors.lastname: Satomi
authors.affiliation: Department of Dentistry, Oral and Maxillofacial Plastic and Reconstructive Surgery, Yamagata Japan. ; Department of Anatomy and Cell biology, School of Medicine, Faculty of Medicine, Yamagata University, Yamagata Department of Anatomy and Cell biology, School of Medicine, Faculty of Medicine, Yamagata University, Yamagata Japan. ; The first two authors contributed equally to this work.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Department of Dentistry, Oral and Maxillofacial Plastic and Reconstructive Surgery, School of Medicine, Faculty of Medicine, Yamagata University, Yamagata Japan.
authors.forename: Takehito
authors.initials: T
authors.lastname: Kobayashi
authors.affiliation: Department of Dentistry, Oral and Maxillofacial Plastic and Reconstructive Surgery, School of Medicine, Faculty of Medicine, Yamagata University, Yamagata Japan.
authors.forename: Mituyoshi
authors.initials: M
authors.lastname: Iino
keywords: dental stress analysis.; mouth rehabilitation