Learning effects of different training models for border molding from the perspective of dental students

BACKGROUND The aim of this study was to investigate the effects of different practical training models on the comprehension and evaluation of practical training among dental students. METHODS The study subjects were all sixth-year dental students at our institute, and the study took place over three consecutive years (n = 58, 63, and 65, respectively). In practical training, all students learned border molding, and practical models were modified each year from plaster models to silicone models and then to silicone models mounted in mannequins. Immediately after completing clinical training, all students were asked to complete questionnaires consisting of 21 items regarding their overall practical training and their clinical comprehension of border molding. All items were rated on a five-point Likert scale, and in order to reduce the large number of interrelated questions, exploratory factor analysis was carried out using maximum likelihood estimation with promax rotation (κ = 4) and Kaiser normalization. The number of factors was chosen using the Kaiser-Guttman rule, which states that the eigenvalue should be larger than 1, and the scree plot criteria. Items that scored less than 0.25 in communality and exhibited factor loading greater than 0.35 for more than one item were excluded. 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. RESULTS Exploratory factor analysis identified the following three factors: "knowledge of border molding"; "contents of practical training"; and "personal learning attitude". The students who used silicone models and mannequins gave significantly better evaluations on the "knowledge of border molding" (p < 0.001, both) and "contents of practical training" (p = 0.046, p < 0.001, respectively) subscales than those who used plaster models. No significant differences were observed between those who used silicone models and those who used mannequins. Moreover, no significant differences were found on the "personal learning attitude" subscale among students for any model. CONCLUSIONS The change in practical training models from plaster to silicone improved student evaluations of border molding training.