Fig. 4: Additional investigation of depth deviation.
a, b The relationship between drilling time in seconds (x-axis) and depth deviation in mm (y-axis); the blue line represents the LOESS (locally estimated scatterplot smoothing) function, while the dots indicate individual measurements. The vertical dashed line marks the drilling time of 5 seconds, while the horizontal dashed line marks the depth deviation of 1 mm and the solid line marks the depth deviation of 0 mm. a ARNS (left) and CNS (right), individual measurement points are shown in blue (ARNS) and yellow (CNS). b Surgeons (left), Students (middle), and Engineers (right), individual measurement points are shown in green (Surgeons), purple (Students), gray (Engineers). c Relationship between participants' age in years (x-axis) and their drilling depth deviation in mm (y-axis); the blue line represents the linear model (LM) function, and the dots indicate individual measurements. d Visualization showing the calculation of the accuracy metrics used. The planned drill hole (25 mm long) is shown in red, the conducted drill hole is shown in gray. Angular deviation was calculated as the angle between the two vectors (dashed lines). Projected translational deviation at entry (red line, C1 to planned vector) and end (red line, C2 to C3/planned vector) as orthogonal distance. The maximum projected translational deviation (primary endpoints) is the larger value of the two projected translational errors. Euclidean deviation (red line, C1 to P1) on the surface and depth deviation (red curly brackets, P2 to C3).
