# In vitro Accuracy of Dental 3D Printers for the Fabrication of Laminate Veneers with Different Preparation Designs

## TL;DR

This study compares the accuracy of dental 3D printers in making models for laminate veneers, finding that the Asiga printer performs best and certain tooth preparation designs affect precision.

## Contribution

The study introduces a comparison of dental 3D printer accuracy for different incisal edge preparation designs in laminate veneer fabrication.

## Key findings

- The Asiga printer demonstrated significantly higher trueness and precision compared to other printers.
- The window preparation design had significantly lower precision than butt-joint and palatal extension designs.
- No significant differences in trueness were found among the preparation designs.

## Abstract

The adoption of three-dimensional (3D) printing in dentistry for prosthetic workflows is increasing. A crucial step in the indirect fabrication of laminate veneers involves creating accurate master casts
from digital impressions. However, there is limited information available regarding the accuracy of dental 3D printers in fabricating these master casts when different tooth preparation designs for laminate veneers are employed.

This study aimed to assess and compare the accuracy (trueness and precision) of dental 3D printers in fabricating master casts for laminate veneers featuring three different incisal edge preparation
designs (butt-joint, window, and palatal extension).

This in vitro, experimental study was conducted on three dental models made of polyether ether ketone (PEEK) with central incisor and canine teeth with three incisal preparation designs of window,
butt-joint, and palatal extension for fabrication of laminate veneers. The models were scanned by the same laboratory scanner, and the standard tessellation language (STL) files were printed by
four printers: Prodent (material jetting [MJ]), Asiga (digital light processing [DLP]), Hunter (DLP), and Luminous (light-emitting diode [LED]), 30 times. A total of 120 printed models were scanned
again, and their scan files in STL format were compared with the reference model file to assess the trueness and precision of the printers. Data were analyzed using paired and independent t-tests,
one-way analysis of variance (ANOVA), and Tukey test (α= 0.05).

Asiga printer showed significantly higher trueness and precision than other printers (p< 0.05). No significant difference was found among other printers in trueness or precision
(p> 0.05). The precision of window preparation design was significantly lower than other preparation designs (p< 0.05). No significant difference was found among other preparation
designs in precision (p> 0.05). The difference in trueness was not significant among the preparation designs (p> 0.05).

Asiga printer showed significantly higher trueness and precision than other tested printers for fabrication of laminate veneers. Also, window preparation of the incisal edge resulted in significantly lower precision than butt-joint and palatal extension designs.