Octree-based Virtual Dental Training System with a Haptic Device

The virtual dental training system using a haptic device is becoming a very important training tool for dental education. We propose a new approach that utilizes the so-called EP (Edge Proportion) value, local material stiffness and implicit function to develop a novel dental training system which has useful characteristics such as efficient collision detection, stable haptic interaction and accurate sculpting simulation. In the efficient collision detection approach, the oriented bounding box tree and EP value can be quickly updated for collision detection. The EP value is very important in our approach, because it can also be used to compute haptic force and update the tooth model. In the stable haptic interaction approach, we use the spring-damper force model and a simple force filter to obtain stable force feedback. Finally, in the precision sculpting simulation, an implicit function is employed to exactly represent various kinds of dental tools so that accurate calculation of cutter- surface intersection can be realized. The proposed system is highly applicable to virtual dental training and practices. Examples of tooth preparations such as inlay and bridge preparation are demonstrated.