Antibacterial effectiveness of dentin bonding systems

This study examined the antibacterial activities of several commercially available glass ionomer cements, dentin bonding systems and luting agents by employing both agar plate diffusion (APD) and growth inhibition (GI) methods. Amalgam and resin composites were also tested as control materials. In both methods (APD and GI), cylindrical specimens were used. Four bacteria strains were tested: Streptococcus mutans, S. salivarius, S. mitis and S. sanguis. These studies were performed using standardized innoculums with selective media, and the assayed materials were directly applied on the assay cultures and plates. The results of agar plate assay were in accordance with the results of growth inhibition method. The glass ionomer cements showed marked antibacterial activity. On the contrary, amalgam, composites, luting agents and dentinal bonding systems did not affect bacterial growth. The sensitivity of the growth method showed that all the strains were inhibited in the same way by each inhibitory material. The data suggest that the use of glass ionomer cements as cavity liners/bases may reduce the consequences of microleakage due to its antibacterial properties.