A flow cytometric analysis of the biodefensive response of deciduous tooth pulp to carious stimuli during physiological root resorption.

The present study observed biodefensive responses of deciduous tooth pulp to advancing caries lesions and analysed the role of physiological root resorption on pulpal defense potential. For this purpose, immunocompetent cell content of deciduous tooth pulp was examined using flow cytometry. A total of 49 deciduous incisor and molar teeth at various stages of physiological root resorption (carious or non-carious) to be extracted for clinical reasons were used in this study. Teeth were classified according to carious lesion depth and root resorption stage. CD3+ lymphocytes were observed to be most prevalent in the pulp and to show remarkable increase along with increase in carious lesion depth. Numbers of CD8+ lymphocytes also increased significantly as carious lesions approached the pulp. However, increase in the number of CD3+ and CD8+ cells did not significantly alter CD4+/CD8+ ratios. The study also found that while B-lymphocytes increased significantly in association with root resorption, there were no significant differences in B/CD3+ lymphocyte ratios. Thus, there was no evidence of irreversible pulpal pathosis in any groups. It can be concluded that pulp maintains its healing and defense capacity against advancing carious lesion and progressive root resorption in deciduous teeth.