Biocompatibility of mineral trioxide aggregate and three new endodontic cements: An animal study

Abstract

Background: Introducing new endodontic cements should await comprehensive investigations
and new formulations have to be tested in vivo before applying in human beings. So, the purpose
of this study was to compare the biocompatibility of new endodontic cements, calcium aluminate
α-aluminate cement (CAAC), calcium aluminate α-aluminate plus cement (CAAC plus), and a
mixture of wollastonite and CAAC cement (WOLCA) and mineral trioxide aggregate (MTA), in
subcutaneous connective tissue of rats.
Materials and Methods: Twenty-seven Wistar rats were divided into three groups of 7, 14, and
30 experimental days. Sterile polyethylene tubes were filled with MTA, CAAC, CAAC Plus, and
WOLCA cement and implanted subcutaneously. Empty tubes were implanted as negative control.
After the experimental periods, animals were sacrificed by anesthetic overdosing. The occurrence
of inflammatory responses was scored according to the previously established scores. Data were
statistically analyzed using Friedman, Wilcoxon, Kruskal-Wallis, and Mann-Whitney tests. The level
of significance was 5% (P<0.05).
Results: There was a statistically significant difference between experimental and negative control
sites in each group (P<0.05). CAAC Plus showed the highest mean scores of inflammation, compared
with MTA, CAAC, and WOLCA cement sits at the end of all periods (P<0.05). There were no
statistically significant differences between inflammatory scores of each site in different experimental
groups, except CAAC plus sites, in which inflammation increased significantly with time (P<0.05).
Conclusion: According to the results of the current study, biocompatibility of CAAC and WOLCA
cement were comparable with that of MTA, but CAAC Plus induced an inflammatory response
higher than MTA, therefore is not biocompatible.
Key Words: Biocompatibility, mineral trioxide aggregate, new endodontic cement, sodium
hexametaphosphate