EVALUATION OF CALCIUM AND HYDROXYL ION RELEASE WHEN CALCIUM HYDROXIDE IS COMBINED WITH GRAPHENE OXIDE AS A VECHICLE -AN IN- VITRO STUDY

Abstract

Background: Calcium hydroxide is widely used as an intracanal medicament because its dissociation releases calcium and hydroxyl ions that contribute to antimicrobial activity and hard-tissue formation. Graphene oxide has been proposed as a vehicle, but its influence on ion release requires evaluation. Aim: To compare the in vitro release of calcium and hydroxyl ions from calcium hydroxide mixed with distilled water and calcium hydroxide mixed with graphene oxide. Materials and Methods: Calcium hydroxide preparations were divided into two groups (n = 5): calcium hydroxide with distilled water and calcium hydroxide with graphene oxide solution. The preparations were placed in polyethylene tubes and immersed individually in 20 mL of deionized water. Calcium ion release was quantified by the o-cresolphthalein complexone colorimetric method at 570 nm at predetermined intervals from 5 minutes to 7 days. Hydroxyl ion release was calculated from the measured calcium ion release, and the groups were compared statistically. Results: Calcium hydroxide mixed with distilled water demonstrated greater calcium and hydroxyl ion release than the graphene oxide-containing preparation throughout the observation period. Significant between-group differences were observed at 20 minutes and on days 6 and 7. The graphene oxide group showed a gradual increase in ion release but remained lower than the distilled-water group. Conclusion: Under the conditions of this study, distilled water promoted greater release of calcium and hydroxyl ions from calcium hydroxide than graphene oxide when used as a vehicle.