Incorporation of CPP-ACP into Fuji VII Glass Ionomer Cement

Objectives: Incorporation of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) into glass ionomer cement (GIC) restorative materials has been shown to increase release of fluoride, calcium and phosphate ions under neutral and acidic conditions. Aim of this study was to assess fluoride, calcium and phosphate ion release from Fuji VII™ (GC Corp, Japan) with and without CPP-ACP (3% w/w) alongside surface hardness and mass loss under neutral and acidic conditions. Methods: Eighty blocks of Fuji VII™ with and without CPP-ACP were subjected to four different solution (5 mL) over a three day period - hydrochloric acid (pH 2.0), citric acid (pH 5.0), lactic acid (pH 5.0) and MilliQ water (pH 6.7). Fluoride, calcium and phosphate ion release, surface hardness and mass loss measurements were carried out every 24 hours. Results: Higher calcium release from Fuji VII™ with CPP-ACP was observed under all acidic conditions. Moderate increase in inorganic phosphate release was observed for Fuji VII™ with CPP-ACP in hydrochloric and citric acids. No significant difference could be measured in fluoride release between Fuji VII™ with CPP-ACP and without, although fluoride release in citric and hydrochloric acids was higher than in lactic acid, which in turn was higher than MilliQ water (control). Initial surface hardness was lower for Fuji VII™ with CPP-ACP, at the end of three days of storage no significant difference in surface hardness could be measured between Fuji VII™ with and without CPP-ACP under all conditions. Similar mass loss profiles were observed for Fuji VII™ with and without CPP-ACP. Conclusion: Incorporation of CPP-ACP into Fuji VII™ has enhanced calcium and phosphate release, while maintaining the materials' fluoride release profile. Increase in ion release for minimal mass loss suggests recharge of material with calcium, phosphate and fluoride may be possible, providing a sustainable release of ions over extended period of time.