The physical properties and ion release of CPP-ACP-modified calcium silicate-based cements

Background: This study investigated the physical properties and ion release of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-modified calcium silicate-based cements (CSCs) and compared the properties of a trial mineral trioxide aggregate (MTA) with two commercially available CSCs, Biodentine (TM) and Angelus (R) MTA. Methods: The setting time, solubility, compressive strength and Vickers surface microhardness of the three CSCs incorporated with 0%, 0.5%, 1.0%, 2.0% and 3.0% (w/w) CPP-ACP were investigated. Release of calcium (Ca2+), phosphate ions (P-i) and pH of the test cements were measured after 24, 72, 168 and 336 h of storage. Results: The addition of up to 1.0% CPP-ACP into Biodentine (TM) and 0.5% into the other cements did not adversely affect their physical properties except for the setting time. The addition of 0.5% CPP-ACP increased Ca2+ released from Biodentine (TM) (after 168 and 336 h), Angelus (R) MTA (after 168 h) and the trial MTA (after 72 h). The addition of 1.0-3.0% CPP-ACP increased Ca2+ and Pi released from all the cements. Biodentine (TM) released more Ca2+ particularly in the early stages and showed shorter setting time and higher mechanical properties than the other cements. The mechanical properties of Angelus (R) MTA and the trial MTA were similar. All the cements produced highly alkaline storage solutions. Conclusions: Up to 1.0% CPP-ACP in Biodentine (TM) improves Ca2+ and Pi release and 0.5% CPP-ACP in Angelus (R) MTA and the trial MTA improves Ca2+ release without altering the mechanical properties and solubility. The addition of CPP-ACP into CSCs prolonged the setting time.