Page 105 - Demo

6Analysis of movements in tooth removal procedures using robot technology103Fig 5. Axis dominance. Presented per ‘mirrored’ group of teeth and their standard deviation. The axis dominance was defined as the percentage of rotation that takes place around each specific axis relative to the other 2. X-ratio = rotation around the bucco-palatal or lingual axis. Y-ratio = rotation around the mesiodistal axis. Z-ratio = rotation around the longitudinal axis. L = lower. U = upper. Range of motion and angular velocityFor each ‘mirrored’ group of teeth (i.e. the 14 and 24) maximum rotations as well as maximum angular velocities were calculated for all 6 directions separately. The averages of maximum rotations in both directions can be interpreted as a ‘range of motion’ along that axis and are presented in Fig. 6. The largest range of motion can be seen in rotations around the longitudinal axis of the tooth, more so in the frontal region. Lowest range of motion was found in the direction of mesial and distal angulation, especially in the upper jaw. The averages of the maximum angular velocity measured in each experiment per group of teeth are presented in Fig 7. Both in upper and lower jaw, highest angular velocities were seen in rotation around the longitudinal axis of the tooth, being more prominent in the upper jaw. This effect was less pronounced in the dorsal region of the upper jaw. A more constant angular velocity was detected across groups in the lower jaw. Tom van Riet.indd 103 26-10-2023 11:59