Dental haptic simulator to train hand skill of student - calibration method to realize visual haptic environment.

In prior work, we have developed dental training simulator to train hand skill of student (HHDTS). In the present study, we performed calibration between haptic device coordinate system and half-mirror coordinate system for our system to realize real clinical situation. As a result, the user can overlay the CG (turbine) onto the stylus of haptic device and intract to the CG (tooth) directly.

Virtual reality simulation training for dental surgery.

In dentistry the exquisite hand skill is required for daily treatments, However, dental students have little chance to treat patients in the clinical training So, present study constructed a process simulation to train the hand skill for tooth extraction, especially impacted wisdom tooth that was an example of the difficult case by using virtual reality haptic device.

A potential function-based scalpel navigation method that avoids blood vessel groups during excision of cancerous tissue.

This study developed support software for liver surgeons; the software can apply potential functions to blood vessels and cancerous tissue and can adjust repulsion and attraction accordingly. Thus, the scalpel can be directly provided with the power to operate on cancerous cells only from a fixed distance, and accidental cutting of blood vessels can be avoided. The direct support provided by this force navigation allows physicians to safely and reliably navigate past blood vessel groups in order to precisely perform excision surgery for liver cancer.

The usefulness of a haptic virtual reality simulator with repetitive training to teach caries removal and periodontal pocket probing skills.

Our aim was to evaluate haptic virtual reality (VR) simulation with repetitive training as a tool in teaching caries removal (CR) and periodontal pocket probing (PPP) skills. For the CR simulation, multilayered virtual models composed of tooth substance, caries, and pulp were developed. Seven students completed three training sessions each, which were scored based on the volume of the cut region, the number of instances of handpiece overload, and total cutting time. For the PPP task, we developed a virtual periodontal disease model and 26 students received training in measuring pocket depth. Pocket probing force was measured and proficiency was evaluated. In the CR task, scores for the second and third training sessions were significantly higher than for the first training session. We likewise obtained effective repetitive training results for the PPP task. Our simulator was effective at teaching hand skills for both tasks within short-term evaluation.

Development of three-dimensional patient face model that enables real-time collision detection and cutting operation for a dental simulator.

The virtual reality (VR) simulator is a useful tool to develop dental hand skill. However, VR simulations with reactions of patients have limited computational time to reproduce a face model. Our aim was to develop a patient face model that enables real-time collision detection and cutting operation by using stereolithography (STL) and deterministic finite automaton (DFA) data files. We evaluated dependence of computational cost and constructed the patient face model using the optimum condition for combining STL and DFA data files, and assessed the computational costs for operation in do-nothing, collision, cutting, and combination of collision and cutting. The face model was successfully constructed with low computational costs of 11.3, 18.3, 30.3, and 33.5 ms for do-nothing, collision, cutting, and collision and cutting, respectively. The patient face model could be useful for developing dental hand skill with VR.

Development of a multi-layered virtual tooth model for the haptic dental training system.

A virtual reality (VR) haptic dental training system could be a promising tool for future dental education. One major challenge is to develop a virtual tooth model which similarly reflected a real tooth having multiple layers with different mechanical hardness in each layer. The multi-layered virtual tooth model was successfully constructed in our virtual system. The constructed model allows us to feel tooth cutting which is similar to that with a real tooth. Through a cutting experiment by using the real tooth, a spring coefficient and a damping coefficient of a dental hard tissue were determined 0.8 N/mm and 1.79 Nsec/mm respectively. The feedback force smoothly altered when crossing the border of regions having different mechanical hardnesses. The constructed model introduced in this study could be a promising tool for acquiring dental hand skills in a virtual learning system.