Design and Development of an Innovative Orthognathic Surgery Simulator Integrating Haptic Feedback for Piezoelectric Cutting

This thesis focuses on the development of a haptic interface to realistically simulate maxillofacial bone cutting using a piezoelectric cutter. Implemented in Unity with the Touch haptic pen (model by 3D Systems), the system replicates the forces and resistances of real surgical procedures, offering a training platform for surgeons and residents to interact in real time with a 3D mandible virtual bone.To accurately simulate bone cutting, a first approach was implemented using a dynamic mesh editing system for real-time geometry modifications. A second approach involved subdividing the bone mesh into cuboid-shaped elements, adding volume and density to improve the precision of the cutting process while maintaining computational efficiency. Despite these advancements, the simulation remains less precise than real piezoelectric cutters, requiring refinements in collision handling and mesh updates to enhance realism and accuracy. Validation of the system demonstrated its reliability in providing realistic haptic feedback during the cutting simulation. The validation process involved two distinct steps. The resoults of these tests confirmed the consistency between the forces measured by the haptic device and the forces needed to cut a PLA phantom using a piezoelectric cutter. Subsequently, three maxillofacial residents evaluated the system, highlighting strengths such as ease of use and visual clarity, while suggesting improvements in haptic feedback and cutting precision. Future work should refine tactile feedback, enhance bone structure representation, and integrate advanced algorithms for more realistic tool interactions. Compatibility with VR devices, such as Meta Quest, could further improve immersion and usability. Despite current limitations, the system demonstrates the feasibility of a haptic simulation platform for maxillofacial surgery, providing a safe and effective training environment that bridges the gap between traditional methods and clinical practice.