Shear bond strength, microleakage and antimicrobial properties of AElitebond

To evaluate the shear bond strength (SBS) and microleakage (ML) to dentin as well as the antimicrobial action against five strains of oral bacteria of AElitebond single primer restorative system.

Fifteen molars were tested to failure for each of the four time periods: 15 minutes, 24 hours, 7 days and 30 days, after final cure. The test specimens were prepared on the dentin surfaces of the extracted molars ground on 600 grit SiC paper. The bonded cylinders were removed from the assembly apparatus after cure, stored in physiological saline at 37 degrees C for the four different time periods and subjected to a shear bond load at 0.5 mm/minute until fractured. For the microleakage determination, Class V cavity preparations were done on the facial surfaces of the roots of 15 canines below the cemento-enamel junction and the specimens thermocycled (500x) between 8 degrees C and 15 degrees C in 2% methylene blue. The teeth were cut into 6 mm thick sections and the sections which included the restorations were separately dissolved in acid. The color intensities of the dissolved sections were measured at a wavelength of 590 nm against a standard curve which was constructed from the dye. The modified model cavity method of Meryon & Johnson (1989) was used to assess the antimicrobial properties of the restorative system.

The mean SBS values (in MPa) were found to be 10.3, 9.8, 11.47 and 9.9 after 15 minutes, 24 hours, 7 days, and 30 days, respectively. There was no significant increase (P < 5%) in the SBS after 15 minutes. The ML of 0.76 micrograms dye/ restoration was relatively low in comparison to the SBS values. The restorative system significantly (P < 5%) inhibited the growth of Actinomyces naeslundii with 88%, Streptococcus mutans with 42%, Streptococcus sanguis with 39% and Streptococcus oralis with 9%. However, the growth of Veillonella parvula was stimulated with 49%.