Effects of surface glazing on the mechanical and biological properties of 3D printed permanent dental resin materials

Abstract

This study aimed to determine the surface glazing effect on the mechanical and biological properties of threedimensional printed dental permanent resins. Methods: Specimens were prepared using Formlabs, Graphy Tera Harz permanent, and NextDent C&B temporary crown resins. Specimens were divided into three groups: samples with untreated surfaces, glazed surfaces, and sand-glazed surfaces. The flexural strength, Vickers hardness, color stability, and surface roughness of the samples were analyzed to identify their mechanical properties. Their cell viability and protein adsorption were analyzed to identify their biological properties. Results:The flexural strength and Vickers hardness of the samples with sand glazed and glazed surfaces were significantly increased. The color change was higher for surface untreated samples than that for the samples with sand-glazed and glazed surfaces. The surface roughness of the samples with sand-glazed and glazed surfaces was low. The samples with sand-glazed and glazed surfaces have low protein adsorption ability and high cell viability. Conclusions: Surface glazing increased the mechanical strength, color stability, and cell compatibility, while reducing the Ra and protein adsorption of 3D-printed dental resins. Thus, a glazed surface exhibited a positive effect on the mechanical and biological properties of 3D-printed resins.

3D Printed Materials for Permanent Restorations in Indirect Restorative and Prosthetic Dentistry: A Critical Review of the Literature

“…Despite the importance of the subject, only one study investigated the biocompatibility of 3D printable resins [ 56 ]. In that study, Nam et al reported that surface glazing increased cell compatibility while reducing the protein adsorption of 3D printed dental resins.…”

“…To enhance the microhardness of printed resins, a possible improvement seems to be surface glazing. Nam et al [ 56 ] found that the Vickers hardness of the samples with glazed surfaces was higher than that of the samples with untreated surfaces.…”

“…Even if biocompatibility testing is performed by the companies and revised by the competent national and supranational administrations, the biological properties of 3D printed materials for permanent restorations, despite the obvious clinical relevance, are almost completely unexplored in the scientific literature. Only one study was found investigating the biological properties of 3D printed resin materials [ 56 ]. In this study, the effect of surface glazing on cell viability was investigated.…”

“…To remove it, specimens were washed in alcohol for 15 min before post-curing, but the authors reported difficulties in completely removing this unpolymerized monomer layer. The presence of these monomers affected cell viability [ 56 ]. By glazing, the leaching of residual monomers is reduced, and hence, the cell cytotoxicity is also reduced.…”