Development of Virtual Palpation System for Dental Education

There has been an increase in the number of dentist since the 1950s in Japan. This has been recognized as one of medical issues in Japan. The increase of dentists causes a reduction of diagnostic opportunity per dentist and becomes a factor which declines the quality of dental therapy. By the way the education contents implemented in dental college has not been changed, where dental students study the knowledge and technique for intraoral radiograph. In the dental examination room, dentist often touches a patient face to identify the causes of disease such as dental curies and/or tumors. This diagnostic method has been called as maxillofacial palpation. Because some of dental diseases can be found by maxillofacial palpation, this diagnostic method has been recognized as the important skill for dentist. However, no practical training of maxillofacial palpation against a patient has been included in the curriculum of dental education. A training system which enables dental students to practice maxillofacial palpation with a patient was requested from the dentists, and then this study aims to develop a virtual training system for maxillofacial palpation that provides dental students to touch a patient face virtually. The system consists of a personal computer and a haptic interface. The computer processes a virtual patient model which reacts graphically and dynamically against the haptic interface operated by a trainee. This study applies free mesh method to the dynamic model of virtual patient model in order to reduce the computation cost. This paper introduces a basic concept of free mesh method and discusses the validity of this method through the experimental results.