The purpose of this study was to evaluate the effect of dicalcium phosphate dihydrate (DCPD) on the biocompatibility of mineral trioxide aggregate (MTA). DCPD was added to MTA (OrthoMTA) to suppress the increase in pH of MTA during hardening, and the change of pH, cytotoxicity, and subcutaneous inflammation reactions in mouse model were observed. The pH of OrthoMTA and DCPD-OrthoMTA at 1st day in phosphate-buffered saline was 12.5 and 12.8, respectively. At 19th day, the pH was 11.6 (OrthoMTA) and 8.8 (DCPD-OrthoMTA). Cytotoxicity of DCPD-OrthoMTA extract was lesser than that of OrthoMTA at high concentration (above 50%) (p<0.05). No significant differences appeared in subcutaneous inflammatory reactions among ProRoot MTA, OrthoMTA and DCPD-OrthoMTA. Therefore, it is likely that there is no apparent relationship between the cytotoxicity and subcutaneous inflammation in our experimental conditions.

The purpose of this study was to evaluate the effect of dicalcium phosphate dihydrate (DCPD) on the biocompatibility of mineral trioxide aggregate (MTA). DCPD was added to MTA (OrthoMTA) to suppress the increase in pH of MTA during hardening, and the change of pH, cytotoxicity, and subcutaneous inflammation reactions in mouse model were observed. The pH of OrthoMTA and DCPD-OrthoMTA at 1st day in phosphate-buffered saline was 12.5 and 12.8, respectively. At 19th day, the pH was 11.6 (OrthoMTA) and 8.8 (DCPD-OrthoMTA). Cytotoxicity of DCPD-OrthoMTA extract was lesser than that of OrthoMTA at high concentration (above 50%) (p<0.05). No significant differences appeared in subcutaneous inflammatory reactions among ProRoot MTA, OrthoMTA and DCPD-OrthoMTA. Therefore, it is likely that there is no apparent relationship between the cytotoxicity and subcutaneous inflammation in our experimental conditions.

Phosphatidylserine (PS) mimics the anti-inflammatory effect of apoptotic cells by binding to the PS receptor of macrophages. In this study, the effect of PS-modified polylactide-co-glycolide (PLGA) nanoparticles on macrophage polarization was investigated.PLGA nanoparticles (PLGAnPs) containing phosphatidylcholine (PC) and PS were prepared using the emulsificationsolvent-evaporation (ESE) technique and classified as follows: 1) PC 100% (PCnP); 2) PS:PC = 50:50 (PSPCnP); and 3) PS 100% (PSnP). PS-grafted PLGAnPs tended to inhibit LPS-induced morphological change into M1 macrophages and mRNA expression of the M1 markers (TNF-α, IL-1β, IL-6, IL-12p40, CD86, and iNOS). In particular, the expressions of TNF-α, IL-6, and IL-12p40 were significantly decreased in the PSPCnP group, as compared to those of the positive control and and PLGAnP groups (p<0.05). Therefore, the study results demonstrate the potential of PS-grafted PLGAnPs in attenuating inflammation and modulating the drug delivery system.