A primary study for measurement on the occlusal contact of the teeth during the final phase of the mandibular movement

1999 Fiscal Year Final Research Report Summary

• Project/Area Number: 10470454
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 矯正・小児・社会系歯学
• Research Institution: Tsurumi University
• Principal Investigator: TSURUTA Masahiko Tsurumi University, School of Dental Medicine, Lecturer, 歯学部, 講師 (80089458)
• Co-Investigator(Kenkyū-buntansha): TOKIWA Hajime Tsurumi University, School of Dental Medicine, Assistant, 歯学部, 助手 (90298266) ; WAKIMOTO Yasuo Tsurumi University, School of Dental Medicine, Assistant, 歯学部, 助手 (00201153) ; KUWAHARA Yosuke Tsurumi University, School of Dental Medicine, Professor, 歯学部, 教授 (30064348)
• Project Period (FY): 1998 – 1999
• Keywords: Jaw movement recording system / 3-D measurement with six degrees of freedom / optoelectoronics / mandibular movement / final phase of the jaw closing

Research Abstract

The purpose of the first year of study was to develop an instrumentation system for recording and analyzing the mandibular movement with six degrees of freedom. It provided high accuracy for recording a slight movement of the contact between upper and lower teeth during final phase of the jaw movement. The out line of the system was as follows : It was consisted with a 3-D image processor, two set of stereo CCD cameras, upper and lower face bows with LED lights, a LED pointer and a personal computer with soft wear. The system was operated with Windows 3.1 and 98.
The purpose of the second year of study was to investigate the accuracy of the recording system and to study the clinical advantages for diagnosis of the patients with TMJ dysfunction. The measurement accuracy of linearity was indicated with 99.99%. The average measurement accuracy in three dimensions was 0.06mm. The mechanical and electrical stability of the system was 0.055mm in three dimension. The accuracy to detect the LED movement was confirmed by analyzing the pattern of paths of LED. Series of jaw movement of the subjects with healthy normal oral function were recorded and analyzed with this system. The results indicated that the paths of the jaw movement were clearly recorded and confirmed the usefulness to observe the details of jaw movement.