การศึกษาเปรียบเทียบตำแหน่งของหลังส่วนบนขณะทำงานของนิสิตทันตแพทย์ที่ใช้และไม่ใช้ระบบวิเคราะห์แนวโน้มการเจ็บป่วยจากท่าทางการทำงานและปรับปรุงท่าทางการทำงานอัจฉริยะ A Comparative Study on Position of Upper Back among Dental Students with and without the Intel

Abstract

Objective: To compare position of upper back among dental students withand without the intelligent posture trainer system during work. Methods: Inthis 2x2 crossover experimental design, 16 dental students wererandomized to either of the two groups (with feedback = 8 and with nofeedback= 8) separated by a washout period of 7 days. Personalizednotification signal of working position was transmitted to the database whileworking (scaling with ultrasonic scaler). The intelligent posture trainersystem recorded measurement on 2 axis direction of the upper back inbend (flexion) and tilt (lateral flexion). Subjects were attached by anaccelerometer sensor at 4th thoracic spine. While the information wasdownloaded every 5 seconds, the system gave feedback to the user byvibrotactile signal as soon as an improper position with injury risk wasdetected. In no-feedback group, no vibrotactile signal notification wasprovided. Data were collected from the system until finishing the wholemouth, and compared for mean values of 10th, 50th, and 90 th percentiles ofupper back bend and tilt were compared between feedback and nofeedbackgroups. Results: The degree of bending upper back of 10 th, 50 th,and 90 th percentile in the feedback group were 11.31  7.89, 18.68  9.34,and 23.87  9.9, respectively. The degree of bending in no-feedback groupwere 19.20  8.9, 25.22  9.32, and 29.57  9.83 degree. The degree oftilting direction of the upper back of 10 th, 50 th, and 90 th percentile, in thefeedback group, were 2.84  2.77, 5.72  3.87, and, 8.17  3.89, respectively.In no-feedback group, they were 5.58  4.24, 10.39  6.58, and 15.01  8.44degree. Degree of movement the upper back of the bend and tilt directionin the 2 groups was significantly different (P < 0.05, paired t-test) at 10th,50th, and 90 th percentiles. Conclusion: The degrees of bending and tiltingin upper back of the feedback from the intelligent posture trainer groupwere significantly smaller when compared with no-feedback.Keywords: musculoskeletal disorders, Vibrotactile biofeedback, accelerometersensor, personalization