The use of virtual reality (VR) training in dentistry is a recent innovation and little research has been conducted to evaluate its use. For each preclinical exercise carried out the VR software currently records a final mark for the procedure, the time taken to complete the procedure and the number of 'internal' assessments carried out by the student. The aims of this study were two fold; a critical appraisal of the software by the students using a structured feedback together with an assessment of any link between the preparation time, final mark and number of evaluations. Sixteen 2nd year undergraduate dental students spent 6 hours cutting an unlimited number of Class I cavities and Class II cavities. The final mark awarded by the VR software together with the overall preparation time and number of evaluations for each cavity were recorded. For the Class I cavity the mean mark obtained was 66.8, the mean preparation time was 12.5 mins and the mean number of evaluations was 6.7. For the Class II cavity the mean mark was 26.5, the mean preparation time was 18 mins and the mean number of evaluations was 7.0. Final marks were also stratified into quartiles (0-24, 25-49, 50- 74, 75-100). For the Class II cavity the time taken to complete the cavity and the number of evaluations made were greater for those cavities that gained a mark of 50 or more. In conclusion, this initial evaluation of the DentSim VR package was a generally positive undergraduate educational experience. The class II cavity was more difficult to cut than the class I which was reflected in the mean scores. There was also a trend towards higher marks being associated with longer preparation times and more evaluations during the preparation.