Morphological, chemical and antimicrobial analysis of glass ionomer cements used for ART in posterior primary teethGlass ionomer cements (GICs) have been gaining prominence as material for atraumatic restorative treatment (ART) due to their acceptable ph

Resumo

Glass ionomer cements (GICs) have been gaining prominence as material for atraumatic restorative treatment (ART) due to their acceptable physicochemical and biological properties. Objective: To analyze the surface morphology, chemical constitution, and antimicrobial action of GICs used for ART in posterior primary teeth. Material and methods: The tested materials were Vitro Molar®, Ketac Cem Easymix® and Riva Self Cure®. For the structural and chemical analysis, polyethylene tubes with an internal diameter of 3 mm and 3 mm in length were prepared, filled, and then transferred to a chamber with 95% relative humidity and a temperature of 37oC. The surface morphology of the tested materials was examined by scanning electron microscopy (SEM) and main components were investigated by energy-dispersive X-ray microanalysis. For the antimicrobial efficacy analyses, strains of Streptococcus mutans (ATCC 27853) were used. Petri dishes with brain heart infusion agar (BHIA) were inoculated with the microbial suspensions and three cavities were made in each agar plate and filled with one of the GICs. The plates were pre-incubated for 1 hour at room temperature and then incubated at 37oC for 24 to 48 hours. The inhibition zone around each well was recorded in mm. Results: SEM revealed irregular and rough external surface. Cracking was not observed. The main constituents were found to be aluminum, silicon, sodium, and fluoride. Barium was only observed in Vitro Molar®, while lanthanum was only observed in Ketac Cem Easymix®. Elemental mapping of the outer surface revealed high concentration of aluminum and silicon. Inhibition halos were only observed in Riva Self Cure®. Conclusion: The GICs presented irregular outer surfaces and similar chemical elements. Only Riva Self Cure® showed antibacterial action against the S. mutans.