Bond strength of vinyl polysiloxane tray adhesive to 3D-printed tray materials: A comparison study.

Abstract

Purpose: To understand the effectiveness of traditional vinyl polysiloxane (VPS) tray adhesive on 3D-printed custom tray material.

Materials and methods: Custom tray specimens were designed using Meshmixer (Meshmixer, San Rafael, CA, USA) and made of urethane dimethacrylate (UDMA) Megatray (Select Dental, New York, USA), Formlabs Custom Tray Resin (Formlabs, Somerville, MA, USA), and Asiga DentaTRAY (Asiga, Sydney, Australia). Each tray was designed to have a flat 25 mm x 25 mm base, a wall of 6 mm height angled at 45 degrees to the base, and an attachment area for testing. The UDMA samples served as the study's control group. Printed trays were either unaltered or abraded with 100-µm aluminum oxide at 30 bar. VPS Tray Adhesive (Kerr, Michigan, USA) was placed on the trays and allowed to dry in accordance with the manufacturer's instructions for use. Aquasil Ultra + Smart Wetting Tray Impression Material (Charlotte, North Carolina, USA) was placed on the tray and allowed to set. A universal testing machine (Model E10000, Instron Corp, Massachusetts, USA) was used to place 1.4 kg of pressure on the tray specimen to mimic intraoral pressure. Then, it was pulled to conduct the peel test, separating the custom tray from the VPS. A one-way ANOVA was performed with tray group serving as the independent variable and maximum load to peel as the dependent variable. Two independent planned comparisons were performed to test impression material (Asiga vs. Formlabs) and effects of abrasion (Unaltered vs. Air-Particle Abrasion).

Results: The Asiga-Unaltered tray group exhibited the highest adhesive properties of all trays, with a mean force of adhesive failure of 76.94 ± 6.98 N. The lowest was the Asiga-Air-Particle Abrasion group with a mean value of 56.78 ± 6.07 N. The Asiga-Unaltered test group results reflect the most similar results to the UDMA control group with values of 76.94 ± 6.98 N and 75.12 ± 6.77 N, respectively.

Conclusions: The Asiga DentaTRAY Resin performed the best with the highest load to peel values when compared to the control and Formlabs Custom Tray Resin. It was also determined that air-particle abrading of the 3D-printed trays resulted in lower values of adhesion. Some 3D-printed resins could provide comparable, if not better retention of VPS when compared to traditional UDMA tray material.