title: Accuracy of a Real-Time, Computerized, Binocular, Three-Dimensional Trajectory-Tracking Device for Recording Functional Mandibular Movements.
abstract: OBJECTIVE
  Developments in digital technology have permitted researchers to study mandibular movements. Here, the accuracy of a real-time, computerized, binocular, three-dimensional (3D) trajectory-tracking device for recording functional mandibular movements was evaluated.
  
  
  METHODS
  An occlusal splint without the occlusal region was created based on a plaster cast of the lower dentition. The splint was rigidly connected with a target on its labial side and seated on the cast. The cast was then rigidly attached to the stage of a high-precision triaxial electronic translator, which was used to move the target-cast-stage complex. Half-circular movements (5.00-mm radius) in three planes (XOY, XOZ, YOZ) and linear movements along the x-axis were performed at 5.00 mm/s. All trajectory points were recorded with the binocular 3D trajectory-tracking device and fitted to arcs or lines, respectively, with the Imageware software. To analyze the accuracy of the trajectory-tracking device, the mean distances between the trajectory points and the fitted arcs or lines were measured, and the mean differences between the lengths of the fitted arcs' radii and a set value (5.00 mm) were then calculated. A one-way analysis of variance was used to evaluate the spatial consistency of the recording accuracy in three different planes.
  
  
  RESULTS
  The mean distances between the trajectory points and fitted arcs or lines were 0.076 ± 0.033 mm or 0.089 ± 0.014 mm. The mean difference between the lengths of the fitted arcs' radii and the set value (5.00 mm) was 0.025 ± 0.071 mm. A one-way ANOVA showed that the recording errors in three different planes were not statistically significant.
  
  
  CONCLUSIONS
  These results suggest that the device can record certain movements at 5.00 mm/s, which is similar to the speed of functional mandibular movements. In addition, the recordings had an error of <0.1 mm and good spatial consistency. Thus, the device meets some of the requirements necessary for recording human mandibular movements.
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.|Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.|Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, Beijing, China.|Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Zhao
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.|Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.|Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, Beijing, China.|Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors.forename: Huifang
authors.initials: H
authors.lastname: Yang
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.|Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.|Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, Beijing, China.|Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors.forename: Huaxin
authors.initials: H
authors.lastname: Sui
authors.affiliation: Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, Beijing, China.
authors.forename: Satyajeet Sudhir
authors.initials: SS
authors.lastname: Salvi
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.|Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.|Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, Beijing, China.|Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.|Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.|Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, Beijing, China.|Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors.forename: Yuchun
authors.initials: Y
authors.lastname: Sun
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D008334:Mandible / Q000502:physiology*; D009068:Movement; D014584:User-Computer Interface