Technical note: antimicrobial action of glass-ionomer lining cement on S. sanguis and S. mutans

There are a number of glass-ionomer lining cements available to the profession. It is generally agreed that the glass-ionomer cements demonstrate reasonably good biocompatibility. The purpose of this study was to evaluate the antimicrobial activity of six glass-ionomer cements on S. sanguis and S. mutans. Forty-eight plates of TSA-SRBC (10%), each with 3.0-mm-diam. wells, were divided into two groups (1 and 2) of 24 each. Group 1 was inoculated with S. sanguis (10558) and Group 2 with S. mutans (6715-13 w.t.). Each well was filled with 4.0 mg of one of the following liners: Glassic (A), Shofu lining cement (B), GC lining cement (C), Ever Bond (D), Gingiva Seal (E), and Ketac Bond (F); the empty wells served as control. Plates were incubated under microaerophilic conditions at 37 degrees C, and checked daily over seven days for inhibition zones. Average inhibition zones (mm) at 7 days were as follows: Group 1-1A = 10.00, 1B = 7.83, 1C = 18.50, 1D = 13.00, 1E = 8.67, and 1F = 9.33; Group 2-2A = 3.08, 2B = 10.25, 2C = 12.75, 2D = 15.58, 2E = 8.83, and 2F = 3.20. All control wells were 0.0 GC liner and Ever Bond showed significantly greater overall inhibition of microbial growth than did other tested liners (p less than 0.5). A one-way ANOVA and SNK test showed that all tested liners were significantly more toxic toward S. sanguis than toward S. mutans (p less than 0.05).