Evaluation of fracture toughness and bioactive properties of conventional glass ionomer cement using different materials

Glass ionomer cements have found high interest and are oftenly used in dentistry. However, low mechanical strength of these materials limits their usage. The purpose of this study is to evaluate the strength and bioactivitiy of conventional glass ionomer cement by incorporating hydroxyapatite and wollastonite in certain ratios.In the present study 4, 6, 8, 10 % hydroxyapatite and 5, 10, 15, 20 % wollastonite by weight were incorporated into the powder of conventional glass ionomer cement and then the fracture toughness values were calculated. The data obtained from the experiments were analysed with the one way analyses of variance (ANOVA) technique (p<0.05). Differences between groups were determined by Post-Hoc HSD method. The groups that have the highest fracture toughness values were incubated in simulated body fluid (SBF) at certain intervals. The surface analyses of samples was performed by x-ray difractometer (XRD), scanning electron microscope (SEM) and energy dispersive x-ray spectrometer (EDS).It was observed that the incorporation of hydroxyapatite and wollastonite to glass ionomer cement significantly increased the fracture toughness. (p?0.05). After the analyses of XRD and SEM, neither groups showed bioactive properties.