An evaluation by dental clinicians of cutting characteristics and haptic perceptions in 3D-printed typodont teeth: A pilot study

Abstract

Objectives: This study aimed to compare the haptic perception of clinicians to the cutting response of 3D-printed typodont teeth and commercial typodont teeth and human extracted teeth.

Methods: Twenty clinicians were asked to perform a Class I cavity preparation on commercial typodont teeth, 3D-printed typodont teeth, and human extracted teeth, while the forces were recorded via a three-axis load cell. The haptic perception of clinicians was also evaluated through a response questionnaire comparing commercial and 3D-printed typodont teeth.

Results: The study found that clinicians used similar forces (p = 0.53) to cut both the 3D-printed typodont teeth (1.37 N) and the human extracted teeth (1.44 N), but more force was needed to cut the commercial typodont teeth (3.71 N). The response questionnaire indicated that clinicians rated the 3D-printed typodont teeth highly compared to the commercial teeth. The 3D-printed dentine received favorable feedback from clinicians, and the 3D-printed enamel was rated higher compared to the commercial equivalents.

Conclusions: The results of the study suggest that 3D-printed typodont teeth offer a comparable haptic perception to human extracted teeth and can be used as an effective tool for preclinical dental learning. Moreover, the study highlights the advantages of 3D-printed typodont teeth over commercial typodont teeth in terms of haptic perception.

Keywords: 3D printing; dental education; haptic perception; operative; preclinical training; simulation‐based medical education.

FIGURE 1

Positions of the 3D‐printed typodont teeth within the Frasaco mandibular plate, including other Frasaco typodont teeth mounted within a phantom head.

FIGURE 2

(A) Images of the 3D‐printed mandibular first molar. (B) Reconstructed X‐ray microtomography (XMT) images of the 3D‐printed typodont tooth. (C) 3D renderings of the 3D‐printed typodont tooth. Reconstructed XMT images of 3D‐printed dentine from the mandibular first molar, showing (D) a fully formed pulp, complete with root canals, (E) a semi‐formed pulp, with limited root canals, and (F) no pulp cavity.

FIGURE 3

The geometry of the 3D‐printed typodont tooth was designed using the jaw mounting from a Frasaco typodont tooth and the crown of an extracted mandibular first molar. 3D renderings from reconstructed XMT images of (A) Frasaco typodont tooth, (B) extracted mandibular first molar, and (C) 3D‐printed typodont tooth developed in this study.

FIGURE 4

The experimental setup used in Study 1 for measuring the forces required to cut the specimens. (A) A schematic diagram of an embedded specimen mounted on a three‐axis load cell. (B) A photograph of the three‐axis load cell housed in a container to provide a drainage system. (C) A photograph of an embedded Frasaco typodont tooth mounted on a three‐axis load cell, before the addition of the rubber dam. (D) A photograph of a human extracted tooth being cut by a participant, with the three‐axis load cell positioned underneath the rubber dam to prevent damage from irrigation.

FIGURE 5

Mean force used by clinicians to cut the 3D‐printed typodont teeth, Study 1. Extracted mandibular molars and artificial mandibular molars from Frasaco were used as comparisons. Directions of cut were defined as; mesiodistal (X), buccolingual (Y), and occlusal (Z). Error bars are presented as the standard deviation (SD) of the sample (n = 20).

FIGURE 6

Dental educators’ response to the questions to the numerical response scale questions included in the questionnaire, rating the key features of the 3D‐printed typodont (i.e., occlusal surface, perception of cutting enamel, dentine and exposing the pulp). Mean values are given within the bow and whisker plot per question (marked “*”). Median values are given as a solid line within the plots.