Bioactivity Potential of EndoSequence BC RRM Putty

• EndoSequence root repair material putty did not encourage the formation of apatite on the material surface in vivo.
• Although tricalcium silicate–based materials are hydraulic, the material properties improve in the presence of water when not in contact with other solutions.
• The environmental conditions affect the hydration of the EndoSequence RMM putty and consequentially the material interaction with the environment.
• In vitro material assessment may not be representative of the clinical situation.

IntroductionThe aim of this study was to characterize and assess the interaction of EndoSequence BC RRM putty (Brasseler USA, Savannah, GA) in contact with blood and simulated body fluid. Tricalcium silicate–based materials are in contact with blood and tissue fluids during and after their setting. These materials are hydraulic; thus, their properties improve in moist conditions. However, specific environmental conditions may modify the material setting.MethodsEndoSequence BC RRM putty was characterized by scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction analysis. This was done before setting and after contact with water, Hank's balanced salt solution, and heparinized whole blood. Furthermore, characterization of an explanted material from a failed root-end surgery was performed.ResultsThe EndoSequence BC RRM putty was composed of tricalcium silicate, tantalum oxide, and zirconium oxide. The tricalcium silicate reaction led to the formation of calcium hydroxide, and this was evident over the putty in contact with water and Hank's balanced salt solution. In the latter case, there was also the formation of globular crystals synonymous with hydroxyapatite formation. The material in contact with blood exhibited a poorly crystalline surface with additional peaks for calcium, phosphorus, and chlorine, whereas the material retrieved from the failed root-end surgery had deposition of calcium carbonate on its surface.ConclusionsThe environmental conditions affect the hydration of the EndoSequence RMM putty and consequentially the material interaction with the environment. However, in vitro material assessment may not be representative of the clinical situation because carbon dioxide present in vivo leads to the formation of calcium carbonate rather than the hydroxyapatite reported in in vitro studies.