In vitro evaluation of the physical characteristics and push-out bond strength of new experimental nano-MTA

This research assessed two materials to be used as endodontic sealing material. The setting time, pH change, calcium ions release, microhardness and push-out bond strength were compared.

In this in vitro experimental study, comparison was done between: one commercial perforation repair material MTA Angelus and experimental Nano-MTA. For each material, testing for setting time was done using Vicat apparatus, measurement of pH values was established by pH meter, the discharged calcium ions were measured at 1 day, 1 week and 4 weeks post setting via Spectro-photo-meter, three diagonal indentations were created at each specimen surface using Vickers hardness machine. Two groups (n = 10) of maxillary central incisors were used according to the type of root-end filling material. To determine the bond strength, the universal testing apparatus was used. The de-bonded specimens were examined under the stereo-microscope to assess fracture mode.

Nano-MTA and MTA angelus were similar in pH change, setting time and push-out strength records. The nano-MTA group showed significantly higher microhardness and Ca ion release.

Under the parameters of the current investigation, we can conclude that the physical properties of Nano-MTA and commercially available MTA cement (MTA-Angelus) are comparable. Nano-MTA showed higher hardness properties and higher Ca ions release than MTA-Angelus, which could be considered as a potential property to be used as a dentin repair and root-end filling material.