Antimicrobial and Anti-Caries Effect of New Glass Ionomer Cement on Enamel Under Microcosm Biofilm Model.

The occurrence of caries lesions adjacent to restorations is a serious problem in Dentistry. Therefore, new antimicrobial restorative materials could help to prevent recurrent carious lesions. This study evaluated the effect of a new glass ionomer cement (Ion Z) on the viability of a microcosm biofilm and on the development of enamel demineralization. Enamel samples were filled with the following materials (n=9): A) Ion-Z (FGM Ltda); B) Maxxion R (FGM Ltda); C) Ketac Fil Plus (3M ESPE) and D) no restoration (control). The samples were then exposed to human saliva mixed with McBain saliva (1:50) containing 0.2% sucrose for 14 days. The live and dead bacteria were quantified by fluorescence using a confocal laser-scanning microscope. The enamel demineralization was analyzed using transverse microradiography (TMR). The data were submitted to ANOVA/Tukey or Kruskal-Wallis/Dunn test (p<0.05). Ion Z induced a higher percentage of dead bacteria (60.96+/-12.0%) compared to the other groups (Maxxion R: 39.8+/-6.7%, Ketac Fil Plus: 43.7+/-9.71% and control 46.3+/-9.5%). All materials significantly reduced the average mineral loss compared to control (Ion-Z 25.0+/-4.2%vol, Maxxion R 23.4+/-8.0%vol, Ketac Fil Plus 30.7+/-7.7 and control 41.2+/-6.6%vol). Ion-Z was the only material able to significantly improve the mineral content at the surface layer (Zmax: 63.5+/-18.2%vol) compared to control (38.9+/-11.3%vol). Ion-Z shows antimicrobial potential, but its anti-caries effect was similar to the other materials, under this model.