Temperature changes in 2% chlorhexidine gluconate using two activation methods with different intensity levels

Abstract

Background: Chlorhexidine is an irrigant solution widely used in root canal treatment because of its good antimicrobial properties. However, its mixture with sodium hypochlorite results in the appearance of substance called p-chloroaniline, a cytotoxic substance. This is also found when chlorhexidine is heated. The use of passive ultrasonic irrigation is related to an irrigant thermal increase, which can cause the appearance of p-chloroaniline. Thus, the objective is to establish the influence of ultrasonic and sonic activation, with the use of different intensities, upon the temperature of chlorhexidine gluconate (CHX). Material and Methods: The following groups were established: control (without activation), ultrasonic activation and sonic activation. A 0.5-ml volume of CHX was placed in an Eppendorf tube in a thermo-static bath at 37°C. Both methods resulted in immediate CHX activation. The temperature was recorded every 30 seconds between 60 and 180 seconds. The statistical analysis was performed based on the Mann-Whitney U-test. Results: Both groups subjected to activation showed higher temperatures than the control group, and increased activation intensity was associated to greater temperature increments in both activated groups. Conclusions: Both ultrasonic and sonic activation are correlated to temperature increase in CHX.