IADR Abstract Archives
Development of Apatite-Ionomer Cement - Influence of differences in mixture ratio of GIC-glass, liquid and hydroxyapatite -
Objectives: We have developed a novel material, apatite-ionomer cement (AIC) blended glass-ionomer cement (GIC) and hydroxyapatite (HAp) powder. In order to elucidate how porous spherical HAp reacts in AIC, we examined the influence of differences in compounding conditions of GIC powder, liquid and HAp on mechanical strength and chemical properties.
Methods: Conventional GIC for pit and fissure sealing (Fuji III, GC Co., Tokyo, Japan) were used as the control and base material for AIC. AIC powder were made by mixing Fuji III powder and porous spherical shaped HAp (Taihei Chemical Industrial Co., Osaka, Japan). Three GIC and two AIC groups were made according to Table 1. The compressive strength of specimens were measured by a universal testing machine (Autograph AGS-X, Shimadzu Co., Kyoto, Japan) at a crosshead speed of 1.0 mm/min. In addition, specimens were immersed into deionized water for five days and then analyzed the concentration of fluoride ion immersed from specimens by a fluoride electrode (6561-10C, HORIBA Ltd., Kyoto, Japan) connected to an ion analyzer (D-53, HORIBA Ltd.).
Results: Between three GIC groups, the compressive strength increased according to Powder and Liquid ratio (P/L), and significant differences were observed between each groups (GIC-L: 73.12±9.19 MPa, GIC: 109.22±5.43 MPa, GIC-H: 131.07±14.39 MPa). There was no significant difference in compressive strength between the AIC and the AIC-H (AIC: 119.36±7.19 MPa, AIC-H: 127.26±10.38 MPa), and there were no significant differences in the compressive strength of the AIC and GIC-H. In addition, the concentration of fluoride ion released from the AIC and AIC-H groups were not significantly difference from that from the GIC-L group (p>0.05).
Conclusions: Regardless of the amounts of GIC glass powder, AIC get the superior mechanical strength comparable to that of GIC with larger amount of glass powder, and the fluoride ion release property comparable to GIC with smaller amount of liquid.
Methods: Conventional GIC for pit and fissure sealing (Fuji III, GC Co., Tokyo, Japan) were used as the control and base material for AIC. AIC powder were made by mixing Fuji III powder and porous spherical shaped HAp (Taihei Chemical Industrial Co., Osaka, Japan). Three GIC and two AIC groups were made according to Table 1. The compressive strength of specimens were measured by a universal testing machine (Autograph AGS-X, Shimadzu Co., Kyoto, Japan) at a crosshead speed of 1.0 mm/min. In addition, specimens were immersed into deionized water for five days and then analyzed the concentration of fluoride ion immersed from specimens by a fluoride electrode (6561-10C, HORIBA Ltd., Kyoto, Japan) connected to an ion analyzer (D-53, HORIBA Ltd.).
Results: Between three GIC groups, the compressive strength increased according to Powder and Liquid ratio (P/L), and significant differences were observed between each groups (GIC-L: 73.12±9.19 MPa, GIC: 109.22±5.43 MPa, GIC-H: 131.07±14.39 MPa). There was no significant difference in compressive strength between the AIC and the AIC-H (AIC: 119.36±7.19 MPa, AIC-H: 127.26±10.38 MPa), and there were no significant differences in the compressive strength of the AIC and GIC-H. In addition, the concentration of fluoride ion released from the AIC and AIC-H groups were not significantly difference from that from the GIC-L group (p>0.05).
Conclusions: Regardless of the amounts of GIC glass powder, AIC get the superior mechanical strength comparable to that of GIC with larger amount of glass powder, and the fluoride ion release property comparable to GIC with smaller amount of liquid.