Influence of vat polymerization methods on surface and bonding behavior of additive manufactured dental resins

To investigate the surface roughness (Ra), shear bond strength (SBS), and Vickers hardness number (VHN) of additive manufactured interim resins manufactured through different vat polymerization techniques.

Samples were divided into four groups; additive manufacturing technology (Stereolithography:S-FL; Digital light processing:D-AS; Liquid crystal display:L-PH) and subtractive manufacturing technology (Polymethylmethacrylate: MP) (n = 10). After polishing, the Ra values were measured and resin material was then applied. Following thermocycling, SBS tests and VHN tests were carried out. The obtained data were evaluated using one-way analysis of variance (ANOVA) (a = 0.05).

Significant differences were observed between the groups for SBS (P = 0.02) and VHN (P < 0.001), whereas the Ra values were not statistically significant (P = 0.148). D-AS and L-PH had higher and similar SBS (P = 1.000) while MP had statistically lower SBS. D-AS demonstrated higher VHN than all groups (P < 0.001) with the exception of S-FL (P = 0.831). MP had lower VHN than all groups (P < 0.01) other than L-PH (P = 0.143).

All fabrication methods had clinically acceptable SBS values, L-PH and D-AS had higher results. D-AS demonstrated superiority in terms of VHN, all groups exhibited comparable Ra values.