Experimental Sealers Containing Metal Methacrylates: Physical and Biological Properties

The aim of this study was to evaluate the physical properties, the antimicrobial effect, and the biocompatibility of dual polymerization experimental sealers after the incorporation of dibutyltin (ET) or calcium (EC) methacrylate at concentrations of 0.5%, 1%, 2%, and 5%.

RealSeal (RS; SybronEndo, Glendora, CA) was used as a commercial control. Materials were evaluated regarding film thickness, degree of conversion, radiopacity, antimicrobial effect against Enterococcus faecalis using the modified direct contact test, and cell viability. Data were analyzed using analysis of variance followed by the Tukey test or the Student-Newman-Keuls test in SigmaPlot 12.0 (Systat Software, Inc, Point Richmond, CA) (P = .05).

The film thickness of the dibutyltin and calcium were greater than experimental sealers following the standards given by ISO 6876:2012. For degree of conversion, dual polymerization was not influenced by the addition of metal methacrylate. Regarding the modified direct contact test, calcium and dibutyltin at all concentrations showed antimicrobial activity when compared with the positive control after 48 hours of contact (P < .05). In cell viability, ET at all concentrations showed high cytotoxicity similar to RS, and EC at concentrations of 0.5%, 1%, and 2% showed moderate cytotoxicity that was less than 5% of calcium and RS.

It was concluded that calcium and dibutyltin methacrylate incorporation in experimental sealers promoted the antimicrobial effect. The incorporation of calcium methacrylate at 0.5%, 1%, and 2% seemed to be a good treatment option to provide antimicrobial activity associated with moderate cytotoxicity and adequate physical properties.