Cytokines as diagnostic markers of pulpal inflammation

AIM: To measure and compare the levels of the cytokines IL-2, IL-6, IL-8, IL-10, TNF-α and IFN-γ in pulpal blood from irreversible pulpitis, asymptomatic caries exposure and normal pulps. METHODOLOGY: Blood was obtained from pulp exposure sites using cotton pellets. Twenty-five samples were obtained from normal teeth, 40 from asymptomatic caries-exposed pulps and 43 from irreversible pulpitis teeth. Cytokine levels were determined by high-sensitivity ELISA. Data were statistically analysed using Kruskal-Wallis and Mann-Whitney U-tests. RESULTS: Significantly higher levels (P < 0.05) of IL-6, IL-8, IL-10, TNF-α and IFN-γ were detected in caries-exposed pulps and irreversible pulpitis as compared to normal teeth. IL-2 and IL-10 levels were significantly higher (P < 0.05) in caries-exposed pulps as compared to irreversible pulpitis, whilst IL-8 was significantly higher (P < 0.001) in irreversible pulpitis as compared to caries-exposed teeth. Most interestingly, IL-6/IL-10 and IL-8/IL-10 ratios were significantly higher (P < 0.001) in irreversible pulpitis compared with both caries-exposed and normal teeth. CONCLUSION: Levels of IL-8 and the ratios of IL-6/IL-10 and IL-8/IL-10 have the potential to be indicators of pulpal inflammation in caries exposure cases. Cytokine estimation in pulpal blood may help in the diagnosis of pulpal inflammation.