Biomechanical simulation of segmented intrusion of a mandibular canine using Robot Orthodontic Measurement & Simulation System (ROSS)

Aim of this study was to investigate the forces and moments during segmented intrusion of a mandibular canine using Cantilever-Intrusion-Springs (CIS). Three different CIS modifications were investigated using a robotic biomechanical simulation system: unmodified CIS (#1, control), CIS with a lingual directed 6° toe-in bend (#2), and CIS with an additional 20° twist bend (#3). Tooth movement was simulated by the apparative robotic stand, controlled by a force-control algorithm, recording the acting forces and moments with a force-torque sensor. Statistical analysis was performed using Shapiro-Wilk, Kolmogorov-Smirnov, Kruskal-Wallis ANOVA and post hoc tests with Bonferroni correction (α = 0.05). The initial intrusive force, which was uniformly generated by a 35° Tip-Back bend, decreased significantly (p