The participants in this study were sixth-year dental students between 2010 and 2012. The practical models were plaster models in 2010, silicone models in 2011, and silicone models mounted in mannequins in 2012. All students were asked to complete an anonymous questionnaire immediately after completion of their clinical training. The questionnaire was composed of 21 items: 10 of these items related to their clinical comprehension of border molding, and the remaining 11 related to evaluations of the overall practical training. All items were rated on a five-point Likert scale (Additional file 1).