In vitro comparison between the effect of Glutaraldehyde-containing Desensitizersand one-step self-etching Adhesiveson dentin permeability in teeth prepared for full-coverage restorations

Objective: The aim of this study was to evaluate and compare in vitro the effectiveness of one-step self-etching adhesive and two glutaraldehyde-containing desensitizers in reducing dentin permeability in extracted human premolar teeth prepared for full-coverage restorations using a dye penetration test. Materials and Methods: Thirty -six intact human premolars were prepared in a standardized manner for full coverage restorations. The exposed coronal dentin was completely covered by nail varnish except for a finish line and a ring area of 2mm coronal dentin. Afterward the specimens were randomized into 4 groups(n=9) according to dentin treatment: group 1, non-treatment samples; group 2, dentin treated with Gluma®; group 3, treated with Systemp®;Group 4, treated with Tetric® N-Bond Self-Etch. After treatment, they were placed in freshly prepared 2% aqueous methylene blue dye for 12 hours and then sectioned in the buccolingual and mesiodistal direction to assess the dye penetration under a stereomicroscope. Dye penetration was recorded according to the ratio of the maximum linear dye penetration length in millimeters to the total dentin thickness. The results were statistically analyzed using one way ANOVA. The Tukey's post hoc test was used to compute multiple pairwise comparisons that identified differences among groups at p<0.05. Results: All dentin treatment agents significantly reduced dentinal permeability versus control. There were significant differences in permeability among dentin treatment agents (p<0.001). The self-etching adhesive group showed the lowest permeability—this was statistically different from both desensitizers. There were no significant differences in permeability among desensitizers (p=0.98). Conclusions: Within the limitations of this study, the dentin treatments revealed different sealing abilities. The one step self-etch adhesive Tetric®N-Bond Self-Etch exhibited the most favorable dentin sealing properties against dye penetration versus both glutaraldehyde-containing desensitizers Gluma® and Systemp®.