Voxel-based interactive haptic simulation of dental drilling

Haptics is one of the most important sensations for dentists to prepare cavity in dental surgery, which is however not easy to simulate in a computer system because of the large drilling force and the small speed of movement and material removal. In this paper, we present a fully voxel-based approach to interactively simulate dental drilling. Different from those voxel/mesh hybrid models, the drilling forces are computed directly from the voxel-representation while considering the factors of teeth's material properties, the posture and forward speed of dentist's drill and the contact surface area. To overcome force discontinuity caused by removal of tooth material, we define two layers of voxels on drill, where the boundary voxels are only employed to compute force feedback and the interior voxels are adopted to remove materials from teeth. The experimental result shows that our force model can produce smooth and large force feedback at a slow movement on haptic devices. Other than haptic rendering, a real-time filtering method directly using voxel representation has also been developed to improve visual rendering in dental simulation.