Method: Three adhesives containing antibacterial components (Gluma 2 Bond (glutaraldehyde)/G2B, Clearfil SE Protect (MDPB)/CSP and Peak Universal Bond (PUB)/chlorhexidine) were compared to same adhesive versions without antibacterial properties (Gluma Comfort Bond/GCB, Clearfil SE Bond/CSB and Peak LC Bond/PLB). The adhesives were applied according to manufacturers' recommendations. Restored teeth (10/group) were sectioned to obtain specimens with cross sectional area of 1.0 mm2 and then tested in a universal testing machine at 0.5 mm/min after artificial saliva storage for one week and one year. The AA of adhesives was evaluated by agar diffusion method and tested against three anaerobe microorganisms (Porphyromonas gingivalis, Prevotella intermedia and Prevotella nigreecens) and four aerobes and facultative (Staphylococcus aureus, Enterococcus faecalis, Lactobacillus casei and Streptococcus mutans). Physiological saline solution (PSS) was used as negative control and 2% chlorhexidine solution as positive control. Adhesives and control groups were inserted in sterilized plastic cylinders and positioned on inoculated agar plate (n=3). After incubation, the inhibition zones (IZ) were measured. µTBS and AA data were evaluated using two-way ANOVA and Tukey post-hoc test (α=0.05).
Result: CSP, CSB and positive control produced IZ against all oral pathogens with G2B against anaerobe microorganisms only. GCB, PLB and PSS did not form IZ. PUB and GCB showed higher µTBS than CSP after one week, while no significant difference was found among adhesives after the storage for one year. Storage for one year reduced the µTBS for GCB.
Conclusion: The AA was not dependant on the presence of an antibacterial component. No significant differences on µTBS were observed among the adhesives. The µTBS of most adhesives did not reduce after storage for one year.