Simulation of interactive cutting tool for craniofacial osteotomy planning

Engineers and scientists from many fields are using three-dimensional reconstruction for visualization and analysis of physical data. Recent advances in medical imaging and surgical techniques have made possible the correction of severe facial deformities and fractures. Surgical correction techniques often involve the direct manipulation-both relocation and surgical fracture-of the underlying facial bone. Craniofacial surgeons now a days use 3D models of human face to diagnose and analyze abnormalities and hence to plan their basic surgery procedures. To work with these 3D models, it is desirable to develop methods that allow one to interactively manipulate and alter the geometry in an intuitive and efficient manner. In the case of medical/craniofacial data, a baseline interactive task would be to simulate cutting, removal and realignment of tissue. In this paper, we propose a method to simulate a cutting tool using an oriented cube that allows the simulation of tool thickness as well as performing the desired cutting operations on three-dimensional models. This method can be employed interactively, allowing the user to perform the task in an intuitive and easy manner. The tool can be used for osteotomy planning and has been tested on models up to 500, 000 polygons in size and the time for cutting varies from 15 ms for small objects (mandible) to 875 ms for large models (complete skull).