Influence of 2% chlorhexidine on pH, calcium release and setting time of a resinous MTA-based root-end filling material

Abstract

The addition of chlorhexidine (CHX) to a resinousexperimental Mineral Trioxide Aggregate (E-MTA) based root-endfilling material is an alternative to boost its antimicrobial activity.However, the influence of chlorhexidine on the properties of thismaterial is unclear. The aim of this study was to evaluate the influenceof 2% chlorhexidine on the pH, calcium ion release and setting time ofa Bisphenol A Ethoxylate Dimethacrylate/Mineral Trioxide Aggregate(Bis-EMA/MTA) based dual-cure experimental root-end filling material(E-MTA), in comparison with E-MTA without the addition of CHX andwith conventional white MTA (W-MTA). The materials were placed inpolyethylene tubes, and immersed in deionized water to determinepH (digital pH meter) and calcium ion release (atomic absorptionspectrometry technique). The setting time of each material wasanalyzed using Gilmore needles. The data were statistically analyzedat a significance level of 5%. E-MTA + CHX showed an alkaline pHin the 3 h period of evaluation, the alkalinity of which decreased butremained as such for 15 days. The pH of E-MTA + CHX was higher thanthe other two materials after 7 days, and lower after 30 days (p < 0.05).All of the materials were found to release calcium ions throughoutthe 30 days of the study. The addition of CHX increased the calciumion release of E-MTA to levels statistically similar to W-MTA. E-MTAshowed shorter initial and final setting time, compared with W-MTA(p < 0.05). The addition of 2% CHX to MTA prevented setting of thematerial. The addition of CHX to E-MTA increased its pH and calciumion release. However, it also prevented setting of the material