[Effect of digital virtual simulation system for preclinical teaching of access and coronal cavity preparation]

Objective: To investigate the effectiveness of a digital virtual simulation training system applied in the preclinical teaching of access and coronal cavity preparation. Methods: Twenty dental undergraduate students from Peking University School and Hospital of Stomatology were recruited and divided randomly and equally into two groups according to the random number method after being unified with theory training, including access and coronal cavity preparation skills assessment form and Simodont system operation manual. Tests for access and coronal cavity preparation skills by using standard simulation plastic teeth were performed and the scores were recorded as baseline for each student. Students in group of virtual simulation priority were trained using Simodont virtual simulation system, while those in group of phantom-simulator priority were trained using conventional phantom-simulator system. Access and coronal cavity preparation skills of standard simulation plastic teeth were assessed once again and recorded as the second scores for the two groups. Furthermore, the two groups of students exchanged training systems and were assessed and graded once more as the third scores. Finally, all students were asked to fill up a Teaching Questionnaire after the training. The data were then collected and analyzed. Results: For the group of virtual simulation priority, after the training by using Simodont virtual simulation system and conventional phantom-simulator system, the mean score of access and coronal cavity preparation (16.00±1.49) was significantly higher than the baseline score (13.30±1.41) (P<0.05). For the group of phantom-simulator priority, after the training by using conventional phantom-simulator system and Simodont virtual simulation system, the mean score of access and coronal cavity preparation (15.60±1.26) was also significantly higher than the baseline score (13.00±1.89) (P<0.05). Furthermore, in the group of virtual simulation priority, of which the students were trained by using Simodont virtual simulation system first and then conventional phantom-simulator system, the score of access and coronal cavity preparation was significantly higher than the score of training by using conventional phantom-simulator system only (14.30±1.77) (P<0.05). In the group of phantom-simulator priority, of which the students were trained by using conventional phantom-simulator system first and then Simodont virtual simulation system, the score of access and coronal cavity preparation was significantly higher than the score of training by using Simodont virtual simulation system only (14.10±1.45) (P<0.05). Moreover, in the group of virtual simulation priority, the score of training by using conventional phantom-simulator system after using Simodont virtual simulation system was significantly higher than that of training by using Simodont virtual simulation system only (P<0.05). The results of the questionnaire showed that the students fully agreed that "the Simodont virtual simulation system has the characteristics of repeatability, multi-dimension and multiple practice, and provides me with more attention to details" [80% (16/20)], however "it needs to be improved and upgraded to be close to the conventiaonl phantom-simulator system" [90% (18/20)]. Conclusions: Compared with using the conventional phantom-simulator system only, the preclinical teaching effectiveness of access and coronal cavity preparation could be effectively improved by using Simodont virtual simulation system combined with the phantom-simulator training system and might influenced by the training sequence.