The internal consistency of the subscales was assessed using Cronbach’s alpha coefficient. The defined factors were analyzed for the plaster models, the silicone models alone, and the silicone models with mannequins using the Kruskal-Wallis test and follow-up tests using Bonferroni-corrected Mann-Whitney U tests. The significance level was set at p < 0.05. All statistical analyses were performed using SPSS software (version 8.0; IBM SPSS PASW Statistics Base 17.0; IBM Japan, Tokyo, Japan).