Abstract
PURPOSE: This study aimed to evaluate the accuracy of the ultrasonic jaw tracking system by comparing with the conventional electronic system in recording condylar movements. MATERIALS AND METHODS: Twenty-six subjects with normal occlusion participated in the study. The CADIAX(®) 4 and Jaw Motion Analyzer (JMA) systems were used to record condylar movement trajectories during mandibular border movements (protrusive/retrusive, lateral, and wide mouth opening), with each movement repeated three times. Both systems used facebows and sensors to locate the condylar axis points and capture movement trajectory data. Paired t-tests were used for normally distributed data, while the Wilcoxon rank-sum test was applied to non-normally distributed data. The level of significance was set at α = .05. RESULTS: The maximum condylar displacement in the sagittal plane during mandibular border movements and the sagittal condylar inclination (SCI) values on both the left and right sides showed no significant difference between the two systems (P > .05). The Bennett angle (BA) values on both the left and right sides measured by the JMA system were significantly higher than those measured by the CADIAX(®) 4 system (P < .05). The comfort levels of the JMA system were significantly higher than the CADIAX(®) 4 system (P < .05). CONCLUSION: Through this study, it was found that the accuracy of the ultrasonic jaw tracking system was comparable with the conventional electronic system, except for the Bennett angle measurement. In terms of comfort and ease of use, the ultrasonic jaw tracking system is more favored.