Method: The following self-etch systems were tested: a water-acetone-ethanol self-etch adhesive (Optibond All-In-One, Kerr) and a a solvent free self-etch adhesive (Bond 1 SF, Pentron Clinical). Eighty human teeth were sectioned longitudinally and polished with 600 grit SiC paper. The adhesive area was isolated with a cylindrical Teflon mold 3-4 mm. Half of the specimens for each self-etch system were teated with 2% digluconate chlorexidine before self-etch systems were applied. All specimens were thermocycled and stressed at a rate of 0.5mm/min, half of them 24 hours after the application and half of them 3 months later. Failure patterns were analyzed using stereomicroscope and SEM. Statistic analysis was performed.
Result: Optibond All In One showed significantly higher shear bond strength than Bond 1 SF for both testing periods. Chlorexidine statistically significantly improved the shear bond strength of Optibond All In One tested 3 months after the application. Chlorexidine didn’t improve the shear bond strength of Bond 1 SF in any of the observation periods.
Conclusion: The present data indicate that 2% digluconate chlorexidine, as a Matrix Metaloproteinases’ inhibitor, can improve the shear bond strength of a common self-etch system as Optibond All In One.