Educational advantage of crown-shaped prototype plaster model in complete denture practical training

– Analysis of occlusal facet –

Abstract

Purpose: This study aimed to examine whether the newly-developed crown-shaped plaster models are effective for education on the occlusal facet in complete denture practical training.
Methods: Three types of plaster models representing the bimaxillary first molar were employed for both subjective and objective assessments. One type was characterized by the natural tooth crown form (N), and the others by shapes similar to the artificial teeth of Veracia NC (NC) and Veracia SA (SA). One hundred and twenty-nine subjects (68 fourth-year students and 61 fifth-year students) attempted occlusal reshaping and answered a questionnaire to assess the validity of the prototype plaster models. The reproducibility of the relative interocclusal positional relationship in both intercuspal and eccentric positions was evaluated by measuring the distances between reference points from four directions. The efficiency of occlusal reshaping for each plaster model was evaluated by calculating the increase in the area of the occlusal facet per total weight loss in occlusal reshaping. The questionnaire results were analyzed to examine the subjective assessments of the prototype plaster models.
Results: The efficiency of occlusal reshaping for SA was significantly higher than that for NC among fifth-year students. The efficiency of occlusal reshaping for NC was significantly higher than that for SA among fourth-year students pre-reshaped SA (p<0.001). In the questionnaire, several students answered that SA was easier than NC for undergraduate students attempting occlusal reshaping.
Conclusions: These results suggest that the newly-developed crown-shaped plaster models are useful for education on the occlusal facet in comparison with conventional models using a natural crown form.