3D Printed Teeth with Enamel and Dentin Layer for Educating Dental Students in Crown Preparation

Commonly used model teeth are so far uniform in color and hardness. There is no discrimination between enamel and dentin part of a tooth. This condition makes it difficult to train a preparation technique, which is adapted to real tooth substance. The aim of this study was to design and establish a 3D printed tooth with different layers for enamel and dentin for education in crown preparation. A printable tooth with different layers for enamel and dentin was designed, and all 38 fourth-year dental students in the first clinical course in prosthodontics and 30 experienced dentists were trained during a voluntary hands-on course in 2019. Prior to the study, the students had used standard model teeth and real-teeth models in their preclinical education. They had experience in caries removal and preparation on real patients. The perceived benefits of the 3D printed tooth were evaluated by a questionnaire. All individuals in both groups completed the questionnaire, for a 100% response rate. The results showed that the printed tooth was given an overall mean grade of 2.3 (students) and 2.0 (experts) on a scale from 1=excellent to 5=poor. The difference in hardness between the dentin and enamel layer was given a mean of 2.4 (students and experts) and the difference in color a 1.7 (students) and 1.8 (experts). The tooth model with the prepared tooth illustrating an ideal preparation was graded 1.6 (students and experts). In this study, the students had the opportunity to learn a correct crown preparation on a printed tooth with different material properties for enamel and dentin. The learning effect with this tooth model was rated as good on the questionnaire by both students and expert dentists.