Effectiveness of a 3D Printed Training Kit for the Preparation of Access Cavities in Calcified Teeth: A Pilot Study

Abstract

Objective: This study aimed to evaluate the effectiveness of a 3D printed training kit for the preparation of endodontic access cavities in calcified teeth. Methods: The root canal system of a micro-CT scanned premolar was digitally processed to create an endodontic training kit containing 10 teeth with ten different progressive degrees of pulp canal calcification. A tooth variant with a medium calcification degree (5/10) was printed in three copies using opaque resin. Additionally, a set of 10 transparent training teeth with red-colored pulp was produced using PolyJet 3D printing technology, which was used to train the access cavity preparation in a controlled manner due to the transparency of the teeth. Undergraduate students (n=27) and dentists (n=10) each prepared a total of 13 (one pre-training, two post-training) access cavities. Substance loss was quantified by CBCT, and user satisfaction was evaluated by questionnaire. Paired t-tests were used to compare the means for substance loss and procedure time for pre- and post-training conditions. Unpaired t-tests were used to compare differences between students and dentists. The level of significance was set at α=0.05. Results: Mean substance loss before and after training decreased for both students (71.4 versus 54.68 mm3; p=0.069) and dentists (67.3 versus 51.1 mm3; p=0.633), but the difference was not statistically significant. The average preparation time decreased with training for students (420 versus 275 seconds; p=0.100) and dentists (336 versus 158 seconds; p=0.054), but not significantly. Root perforation rates also decreased (students: 6/27 versus 4/27; dentists: 1/10 versus 0/10) . Participants rated the training model as very realistic and useful, despite the difference in material texture. Conclusion: The proposed 3D printed training kit appears to be a suitable tool for undergraduate dental students, which could expand their opportunities to practice the preparation of endodontic access cavities in calcified teeth.