The effect of temperature on the tissue dissolution capacity of 10% calcium hypochlorite solution

Abstract

BACKGROUND: The cytotoxicity of Sodium hypochlorite has always been a concern when used as an endodontic irrigant. Quest for an equally effective, but less toxic substitute has led to researches on Calcium hypochlorite (Ca(ClO)2 ) solutions. But it has been proven that 10% Calcium hypochlorite solution at room temperature (250 C) demonstrated slower rate of tissue dissolution than Sodium hypochlorite. Aim: This study was performed to assess if preheating enhanced the tissue dissolution capacity of 10% Ca(ClO)2 . MATERIALS AND METHODS: Human pulp tissue was obtained from freshly extracted single rooted mandibular premolars. The tissue weight was standardized to 9.5mg. The test groups consisted of freshly prepared Ca(ClO)2 solutions at room temperature (250 C), 450 C and 600 C. Ten specimens were assigned to each group with each specimen immersed in 2ml of the test solution. Five specimens immersed in normal saline made the control group. Every five minutes the tissue was retrieved, blotted dry, weighed and immersed back in fresh 2 ml of solution. This was continued for 60 minutes or till complete dissolution. The percentage difference in weight at each interval was calculated. The values obtained were statistically analyzed using one –way ANOVA. Intergroup comparison at different time intervals was done using Bonferroni test. RESULTS: Ca(ClO)2 solution at 600 C dissolved the tissue significantly faster than other solutions. The tissue dissolution rate of solution at 450 C was greater than that at 250 C. (P< 0.05) CONCLUSION: Within the limitations of this study, it can be concluded that preheating 10% Ca(ClO)2 solution significantly enhanced its tissue dissolution capacity.