Evaluation of voice commands for mode change in virtual reality implant planning procedure.

PURPOSE: In dental implantology, the optimal placement of dental implants is important to meet functional and aesthetic requirements. Planning dental implants in virtual three-dimensional (3D) environment is possible using virtual reality (VR) technologies. The three-dimensional stereoscopic virtual reality environment offers advantages over three-dimensional projection on a two-dimensional display. The use of voice commands in virtual reality environment to replace button presses and other simple actions frees the user's hands and eyes for other tasks. METHODS: Six dentomaxillofacial radiologists experimented using a prototype version of a three-dimensional virtual reality implant planning tool, and used two different tool selection methods, using either only button presses or also voice commands. We collected objective measurements of the results and subjective data of the participant experience to compare the two conditions. RESULTS: The tool was approved by the experts and they were able to do the multiple-implant planning satisfactorily. The radiologists liked the possibility to use the voice commands. Most of the radiologists were willing to use the tool as part of their daily work routines. CONCLUSION: The voice commands were useful, natural, and accurate for mode change, and they could be expanded to other tasks. Button presses and the voice commands should be both available and used in parallel. The input methods can be further improved based on the expert comments.

Evaluation of virtual handles for dental implant manipulation in virtual reality implant planning procedure.

PURPOSE: Many surgical complications can be prevented by careful operation planning and preoperative evaluation of the anatomical features. Virtual dental implant planning in three-dimensional stereoscopic virtual reality environment has advantages over three-dimensional projections on two-dimensional screens. In the virtual environment, the anatomical areas of the body can be assessed and interacted with in six degrees-of-freedom. Our aim was to make a preliminary evaluation of how professional users perceive the use of the virtual environment on their field. METHODS: We prepared a novel implementation of a virtual dental implant planning system and conducted a small-scale user study with four dentomaxillofacial radiologists to evaluate the usability of direct and indirect interaction in a planning task. RESULTS: We found that all four participants ranked direct interaction, planning the implant placement without handles, to be better than the indirect condition where the implant model had handles. CONCLUSION: The radiologists valued the three-dimensional environment for three-dimensional object manipulation even if usability issues of the handles affected the feel of use and the evaluation results. Direct interaction was seen as easy, accurate, and natural.