# 3D‐Printed Multi‐Coloured Teeth Comprising Material Gradients for Dental Education—A Pilot Study

## TL;DR

This pilot study shows that 3D-printed teeth with material gradients can realistically simulate dental procedures and are preferred by students over traditional models.

## Contribution

The study introduces 3D-printed teeth with multi-material gradients for dental education, offering realistic simulation of clinical scenarios.

## Key findings

- Printed teeth were rated higher than standard model teeth for haptic impression and realism.
- Students found printed teeth more realistic for caries removal and restoration tasks compared to extracted teeth.
- Multi-material 3D-printed teeth showed good to very good ratings for simulating dental structures and restorations.

## Abstract

To develop realistic training teeth composed of multi‐material colours and gradients and evaluate them in comparison with the standard model and extracted teeth with a group of students.

Three different teeth were virtually designed by use of multiple STL‐compartments and additively manufactured with different material gradients like colour, hardness and functional properties in a single printing process using MultiJet technology. The teeth included simulated hard‐/softissues and restorative materials like enamel, dentin, pulp, carious dentin, composite, amalgam, and gutta‐percha. The selected teeth were tested by a group of 25 clinical students in a volunteer hands‐on course. They had experience in caries removal, post insertion and preparation on real patients. Study procedures included the removal of a faulty direct and indirect restoration, of gutta‐percha as well as of carious dentin. The properties of the printed teeth for each task were assessed by the students using grades (1 = very good, 2 = good, 3 = satisfactory, 4 = sufficient, 5 = poor). Conventional model teeth and extracted real teeth served as reference.

In comparison to standard model teeth, printed teeth were rated 1.1 ± 0.7, with a grade of 2.4 ± 1.2 for haptic impression and 1.2 ± 0.8 for realistic perception of the exercise. In comparison to extracted teeth, the colour of the enamel(2.1 ± 1.4), the dentin(1.8 ± 1.3) and the carious lesion(1.2 ± 0.8) were evaluated with overall good or very good values. The new features were rated with 1.2 ± 0.7 for the Amalgam filling, 1.0 ± 0.3 for the caries lesion, 1.4 ± 1.5 for the crown, and 2.0 ± 1.0 for the gutta‐percha.

The results of the pilot study confirm the potential of multi‐material additive manufacturing for educational purposes. Students preferred printed teeth in comparison with conventional acrylic and extracted teeth, considering the simulation of a training scenario close to clinical reality.