Experimental composites containing quaternary ammonium methacrylates reduce demineralization at enamel-restoration margins after cariogenic challenge.

Objective: This study evaluated the influence of experimental composites containing quaternary ammonium monomers (QAM) at different concentrations and alkyl chains on demineralization at enamel-composite margins after cariogenic challenge.

Methods: Standardized 4×4mm cavities were cut into 35 bovine enamel blocks, which were randomly divided into seven groups (n=5) and restored with the following experimental composites and commercial materials: (G12.5) - 5% dimethylaminododecyl methacrylate (DMADDM) with a 12-carbon alkyl chain (G12.