Influence of Crystallinity and Porosity on the Features of Endodontic Cement and Natural Hydroxyapatite Based Biomaterial Qualities.

Abstract

Resorption time is essential for bone substitution composite materials. In the best case, it has to coincide with the time of new bone formation. In this work, biphasic biomaterial consisting of natural hydroxyapatite (NHAp) and endodontic cement MTA Angelus (EC) is explored. In our experiment we have used three concentrations of the new composite material: first, EC40/NHAp60 volume %, second, EC50/NHAp50 volume %, and third, EC60/NHAp40 volume %. The main task was porosity exploration of each material and also determination of NHAp crystallite size in the material, both mentioned parameters are essential for the resorption process. Results indicate that the composite material EC40/NHAp60 has the highest porosity, at nearly 8%. We consider that such result is due to the higher content of NHAp in the specimens. In contrast, the lowest level of porosity is in the material EC60/NHAp40, at 5.2%. Porosity of the third material is between the two first mentioned composites. The size of NHAp crystallites in the biomaterial is approximately 20 nm. Consequently, it is possible to assert that the size of the crystallites is nearly the same as hydroxyapatite crystallites in natural bone, which is a prerequisite for biomaterial resorption. The study shows that material with the mentioned porosity and size of crystallites has potential to be used as bone substitute material.