Abstract: PURPOSE: To evaluate the preclinical teaching effects of digital virtual simulation system applied in window-type veneer tooth preparation of undergraduate dental students. METHODS: In the early clinical exposure of five-year undergraduate students from School of Stomatology, Fudan University, Simodont virtual simulation system and conventional phantom-simulator system were alternatively used in the preclinical teaching of veneer tooth preparation. First, after theoretical training and tests of veneer tooth preparation, twenty-three students were randomly divided into two groups. Students in group of virtual simulation priority were trained using Simodont virtual simulation system, while those in group of phantom priority were trained using traditional phantom head to complete the window-type veneer tooth preparation within the specified time, followed by theoretical test again for all students. Then, the two groups of students exchanged training systems and completed the window-type veneer tooth preparation and assessment in the same time. All students were asked to fill up a teaching questionnaire for the evaluation of two training methods. The data were collected and analyzed using SPSS 21.0 software package. RESULTS: The scores of veneer preparations in labial surface cutting volume, labial surface form, cervical margin design, proximal margin design using traditional phantom head training system were significantly higher than those using Simodont virtual simulation system(P<0.05). Statistical results showed that the scores of labial surface cutting volume of phantom priority group were significantly higher than those of virtual simulation priority group(P<0.05), while the scores of incisal length of virtual simulation priority group were significantly higher than those of phantom priority group(P<0.05). The results of the questionnaire showed that the majority of students believed that the traditional phantom head was more helpful than Simodont virtual simulation in identification of labial surface cutting volume, margin form, depth of indicator groove, cutting force, while Simodont virtual simulation was superior to traditional phantom head in safety and future development tendency. CONCLUSIONS: It is necessary to give full consideration of the advantages and limitations of digital virtual simulation system and design reasonable teaching plans. Combined application of digital virtual simulation system and traditional phantom head should be used to improve the preclinical teaching effects of veneer tooth preparation skills for undergraduate dental students.

Key words: Tooth preparation, Virtual simulation, Veneer, Evaluation of teaching effects