Effect of Disinfectants on Bond Strength of All-Ceramics to Dentin

Objective: The purpose of this study was to investigate the effect of dentin disinfectants on the shear bond strength of all-ceramic restorations luted with two different dual-polymerizing systems to dentin. Materials and Methods: Dentin disinfectants; chlorhexidine gluconate-based Concepsis (C) and benzalkonium chloride-based Tubulicid Red (TR) were applied in combination with Variolink 2 (V) and Resilute (R). The buccal surfaces of non-carious extracted human premolars were flattened to expose dentin and subsequently polished with 600-grit wet silicon carbide paper. Each dual-polymerizing luting system had two test groups and a control group. The test groups had the dentin first treated with the dentin disinfectants, and then the all-ceramic restorations were luted with dual polymerizing systems. The dentin without disinfectant application was used as a control. After the all-ceramic samples were luted to all treated surfaces, specimens were thermocycled and tested for shear bond strength until failure. The analysis of the fractured dentin surfaces were performed using Optical Microscope-Nikon ECLIPSE ME 600 (Nikon Co., Japan) at between X10 and X1000 magnifications and the images were analyzed with Image Analyzer LUCIA 4.21 (Nikon Co., Japan). Data were analyzed with one-way ANOVA and Duncan test at a significance level of p<0.05. Results: Mean shear bond strengths in Mpa are as follows; V/Control: 20.57, V/C: 24.24, V/TR: 26.91, R/Control: 15.08, R/C: 17.16, R/TR: 20.36. Application of the two dentin disinfectants increased the shear bond strengths of both Variolink 2 and Resilute systems, but this increase was statistically significant only in Tubulicid Red treated specimens (p<0.05). Surface analysis showed that all of the specimens showed the adhesive failure mode between the dentin and composite luting agent interface. Conclusion: Both Consepsis and Tubulicid Red can be safely used to prevent the potential risk of complications resulting from bacterial activity in clinical luting procedures of IPS Empress 2 restorations.