Effects of water aging on the mechanical and anti-biofilm properties of glass-ionomer cement containing dimethylaminododecyl methacrylate

The aims of this study were to investigate the effects of water aging for up to 6months on the mechanical and anti-biofilm properties of a novel antibacterial glass ionomer cement (GIC) containing dimethylaminododecyl methacrylate (DMADDM).GIC specimens (n=180) which contained DMADDM (0wt.%, 1.1wt.% or 2.2wt.%) were prepared. The mechanical properties surface roughness, microhardness and the surface charge density of ammonium groups were measured before and after water aging for 3 and 6months at 37°C. Further six months aged specimens (n=216) were worn by 6 volunteers in their oral cavities for 24h and 72h. Biofilm formation was analyzed and rated by fluorescence microscopy (FM) and by scanning electron microscopy (SEM). Biofilm viability was analyzed by FM.Water aging did not show any adverse effects on the surface roughness and hardness of the material. The surface charge density of the GIC samples containing DMADDM decreased due to the aging procedure, however, was still higher than that of the GIC without DMADDM. In situ biofilm formation was significantly reduced after 24h on DMADDM containing GIC (p0.05). FM results showed a higher ratio of red/green fluorescence on GIC-DMADDM samples.Incorporating DMADDM into GIC affected the material properties in a tolerable manner even after 6months of storage in water. The new GIC is a promising material to affect the biofilm formation on the surface of restorations.