Chlorhexidine, ethanol, lipopolysaccharide and nicotine do not enhance the cytotoxicity of a calcium hydroxide pulp capping material
Article first published online: 23 APR 2012
© 2012 International Endodontic Journal
International Endodontic Journal
Volume 45, Issue 11, pages 989–995, November 2012
How to Cite
Wheater, M. A., Falvo, J., Ruiz, F. and Byars, M. (2012), Chlorhexidine, ethanol, lipopolysaccharide and nicotine do not enhance the cytotoxicity of a calcium hydroxide pulp capping material. International Endodontic Journal, 45: 989–995. doi: 10.1111/j.1365-2591.2012.02057.x
- Issue published online: 8 OCT 2012
- Article first published online: 23 APR 2012
- Accepted manuscript online: 29 MAR 2012 07:31PM EST
- Received 16 December 2011; accepted 13 March 2012
- pulp capping
Wheater MA, Falvo J, Ruiz F, Byars M. Chlorhexidine, ethanol, lipopolysaccharide and nicotine do not enhance the cytotoxicity of a calcium hydroxide pulp capping material. International Endodontic Journal, 45, 989–995, 2012.
Aim To determine whether cells pre-stressed by known cytotoxic or inflammatory agents are more susceptible to the deleterious effects of a calcium hydroxide formulation used in pulp capping.
Methodology Adult human dermal fibroblasts were treated for 48 h with 0.001% chlorhexidine, 0.2% ethanol, 5 μg mL−1Escherichia coli lipopolysaccharide (LPS) or 0.05 mmol L−1 nicotine. Cells were subsequently treated with the soluble materials extracted from Dycal pellets for an additional 24 h. Controls included cells cultured in medium only and cells exposed to Dycal only. Cytotoxicity was measured using colorimetric MTT, WST and secreted lactate dehydrogenase assays. In addition, mitotic activity was evaluated using a colorimetric histone H3 phosphorylation assay. Data were statistically analysed using anova with Tukey’s multiple comparison post-test and significance at P ≤ 0.05.
Results For all assays, measured values for cells treated with chlorhexidine, ethanol, LPS or nicotine plus the soluble materials extracted from Dycal pellets were significantly lower compared to control (P < 0.05) for all comparisons between experimental conditions. However, between treatments and for comparisons of treatments with Dycal, there were no differences observed for any assay.
Conclusions Calcium hydroxide in a formulation used in dental clinical procedures is highly cytotoxic to cultured cells, as evidenced by several cellular assays. However, other known toxic agents, including chlorhexidine, ethanol, bacterial LPS and nicotine, do not appear to function synergistically to increase the deleterious cellular effects of the calcium hydroxide in an in vitro model of cytotoxicity.