Evaluation of separating media for autopolymerizing acrylic resin fabricated on 3D-printed acrylate-based resin dental casts

Abstract

Statement of problem: Limited data are available regarding the most suitable separating medium for fabricating dental acrylic resin prostheses or appliances on 3-dimensional (3D)-printed resin casts.

Purpose: The purpose of this in vitro study was to investigate and evaluate different separating media in terms of the ease of removal and detail reproduction of an autopolymerizing acrylic resin fabricated on acrylate-based 3D-printed resin casts.

Material and methods: A cube-shaped cast was designed with a built-in truncated cone-shaped hole and a V-shaped groove at the base. Seventy-five casts were 3D-printed using acrylate-based resin and assigned to 5 groups according to the applied separating media: Siliform BEA (silicone-based), IMPRIMO 3D (alginate-based), 3D Modellisolierung (wax-based), TECHNOSIL (alginate-based), and none (control). After the application of the separating media, the truncated cone-shaped holes in the specimens were filled with autopolymerizing acrylic resin. The efficacy of the separating media was evaluated according to the ease of removal on a scale of 1 to 3 and accurate detail reproduction of the V-shaped groove on a scale of 1 to 3 under ×6 magnification. The nonparametric Kruskal-Wallis rank test was used to identify significant differences among the separating media (α=.05).

Results: Significant differences were found among the groups (P<.001). Siliform BEA and 3D Modellisolierung had the best mean rank in both the ease of removal and detail reproduction scores, which were significantly different from those of the alginate-based separating media (IMPRIMO 3D and TECHNOSIL) and the control group (P<.01).

Conclusions: The dedicated silicone- and wax-based separating media for 3D-printed casts exhibited the most favorable performance in terms of ease of removal and detail reproduction.