Does Augmented Visual Feedback from Novel, Multicolored, Three-Dimensional-Printed Teeth Affect Dental Students' Acquisition of Manual Skills?

Although three-dimensional (3D) printing technology is increasingly used in dental education, its application regarding the provision of online visual augmented feedback has not been tested. Thus, this study aimed to: (1) develop two generations of multicolored 3D-printed teeth that provide visual augmented feedback for students conducting the cavity preparation process, (2) assess students' clinical performance after training on the 3D models, and (3) acquire student feedback. For the first-generation model, augmented feedback was obtained from five 3D-printed teeth models for five cavity preparation procedures. Each model comprised three layers printed in green, yellow, and red indicating whether preparation was acceptable, limited, or unacceptable, respectively. The study used a crossover design in which the experimental group trained on five multicolored models and 10 standard plastic teeth, and the control group trained on 15 standard plastic teeth. Students gave positive feedback of the methodology but complained about the printed material's hardness. Therefore, a second-generation model was developed: the model's occlusal plane was replaced with a harder printed acrylic material, and the experiment was repeated. During training, instructors provided external terminal feedback only for performance on standard plastic teeth. Manual grades for cavity preparations on standard plastic teeth were compared. No significant differences were found between the control and experimental groups in both generations' models. However, less instructor time was needed, and similar clinical results were obtained after training with both generations. Thus, multicolored 3D-printed teeth models promote self-learning during the process of acquiring manual skills and reduce student dependency on instructors.