Effect on mechanical and microbiological properties of adding calcium glycerophosphate and xylitol to glass ionomer cement

This study aimed to evaluate the effect on the mechanical and microbiological properties of incorporating calcium glycerophosphate (CaGP) and/or xylitol into resin modified glass ionomer cement (RMGIC). Six experimental cements were tested: i) RMGIC without additions; and RMGIC with ii) 5% xylitol; iii) 10% xylitol; iv) 3% CaGP; v) 3% CaGP and 5% xylitol, or vi) 3% CaGP and 10% xylitol. The compressive strength, diametral tensile strength and surface hardness were determined (24 h and 7 days). Antimicrobial/antibiofilm activity was evaluated. Compressive strength values after 24 h for +3% CaGP & 5% xylitol were higher and similar to RMGIC. After 7 days, +3% CaGP & 5% xylitol presented the highest compressive strength values. The +3% CaGP & 10% xylitol showed the lowest values of diametral tensile strength values (24 h). The RMGIC with +3% CaGP & 5% xylitol showed the highest diametral tensile strength (7 days). The surface hardness (24 h) were highest for the RMGIC and +10% xylitol. After 7 days, +3% CaGP & 5% xylitol showed the highest value. The +3% CaGP & 5% xylitol or +3% CaGP & 10% xylitol showed the lowest levels of microbial/biofilm formation. The addition of CaGP/xylitol promoted improved the mechanical and antibacterial properties of RMGIC.