Effects of iRoot BP and white mineral trioxide aggregate on cell viability and the expression of genes associated with mineralization.

Aim: To evaluate the cytotoxicity and mineralization effects of iRoot BP in human dental pulp cells (hDPCs) and to compare them with those of white mineral trioxide aggregate (WMTA).
Methodology: hDPCs were exposed to prepared dilutions (1 : 1-1 : 10) of the test materials. Cell viability was evaluated using the XTT assay after incubation periods of 24, 48 or 72 h. The expression of mineralization-related genes (bone morphogenic protein, osteonectin, bone sialoprotein, osteopontin, dentine sialophosphoprotein and collagen type 1) and heme oxygenase 1 was measured by quantitative real-time polymerase chain reaction (qRT-PCR) at 24 and 72 h. Statistical differences between test materials were analysed with the Mann-Whitney test.
Results: The 1 : 1 and 1 : 2 dilutions of iRoot BP were associated with higher cell viability after 24 h (P < 0.05). Only the 1 : 1 dilution of iRoot BP had higher cell viability after 48 h (P < 0.05), and there was no difference between iRoot BP and WMTA after 72 h (P > 0.05). Although somewhat variable, according to the gene expression results, iRoot BP had a mineralization potential similar to that of WMTA. WMTA revealed a higher heme oxygenase 1 (HO-1) mRNA level than iRoot BP (P < 0.001).
Conclusions: iRoot BP and WMTA were biocompatible and facilitated odontoblastic differentiation of hDPCs.
(© 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.)