In Vitro Evaluation of Calcium Ions Diffusion and ph Changes of the Periradicular Environment with Conventional Calcium Hydroxide and Synthetic Nanoparticle Calcium Hydroxide as an Intra-Canal Medicament

Background and Aim: Therapeutic effects of calcium hydroxide as an intra-canal medicament depend on its decomposition into hydroxyl and calcium ions. The aim of this study was to determine the diffusion amount of calcium ion and ph changes around the tooth root in the application of conventional calcium hydroxide and Nano particle calcium hydroxide at different times. Material and Methods: In this in vitro experimental study, 50 human single rooted and single canal teeth were divided into two experimental groups of 20 (conventional calcium hydroxide and Nano particle calcium hydroxide with a size of 23±5 nm after confirmation by X-ray Powder Diffraction) and a control group of ten (distilled water). After applying these materials using a K file ISO # 55, seal the coronal part of the canals and transfer to normal saline, the concentration of calcium ions and the ph of normal saline in all groups was measured After 3, 24, 96, 360 and 720 hours. Data were analyzed by one-way ANOVA, Tukey Post Hoc, Bonferroni Post Hoc statistical tests and SPSS 22 software. Results: There was a significant difference between the three groups at different times and in total in comparing the mean ph and mean concentration of calcium ions around the tooth roots (P <0.001). These values for both parameters, in the group of nanoparticle calcium hydroxide were significantly higher than conventional calcium hydroxide and in the group of conventional calcium hydroxide, higher than the control group (P <0.05). Also, the mean concentration of calcium ions in the group of normal calcium hydroxide and nanoparticle calcium hydroxide incresaed. Conclusion: Nanoparticle calcium hydroxide can be a suitable alternative to achieve the desired therapeutic goals due to its ability to emit more calcium ions and higher ph than the conventional type.