The non-occluded digital models of 20 pre-treatment individuals were chosen from the database of Faculty of Dentistry, The University of Hong Kong. Following minimal training with the haptic device (Geomagic® Touch™), the upper model was occluded with the lower model until a stable occlusion was achieved. Seven landmarks were placed on each of the corners of the original and haptically aligned upper model bases. The absolute distance between the landmarks was calculated. Intra- and inter-operator errors were assessed.
The absolute distance between the 7 landmarks for each original and corresponding haptically aligned model was 0.54 ± 0.40 mm in the x-direction (lateral), 0.73 ± 0.63 mm in the y-direction (anterior–posterior) and 0.55 ± 0.48 mm in the z-direction (inferior–superior).
Based on initial collision detection to prevent interpenetration of the upper and lower digital model surfaces, and contact form resistance during contact, it is possible to use a haptic device to occlude digital study models.
The use of 3D digital study models is routine, but new problems arise, such as the lack of “touch” in a virtual environment. Occluding study models requires the sense of touch. For the first time, using haptic technology, it is possible to occlude digital study models in a virtual environment.