Odontoblastic Cell Quantification and Apoptosis within Pulp of Deciduous Teeth Versus Pulp of Permanent Teeth

While the odontoblast ability to respond to injury in permanent teeth (PT) is well established, there is a lack of knowledge about deciduous teeth (DT). Aim of this study was to compare the odontoblasts activity within the pulp of DT versus the pulp of PT. Study design :Dental pulp was obtained from forty-two DT and twenty-seven PT extracted from sixty-five patients (aged 6-16 years). Histomorphometry was carried out and the quantification of odontoblastic layer was assessed. Dental pulps of DT and PT were stained for anti-ssDNA, BCL-2, BCL-x, BAX, caspase3. Results : Pulps from DT were characterized by reduction of odontoblastic layer and greater occurrence of apoptotic odontoblasts. Pro-apoptotic BAX phenotype expression on odontoblasts correlated with the occurrence of numerous activated caspase3 odontoblasts in DT. The number of BAX positive cells was significantly higher compared to BCL-2 positive cells in the odontoblastic layer of the DT (p=0.03). Since BAX and BCL-2 proteins have an inverse role in the regulation of the apoptosis, this finding suggests that odontoblasts have a predominant pro-apoptotic phenotype in DT. Conclusion: According to our results, the odontoblasts of DT can be assumed to have a lower reparative activity if compared to odontoblasts of PT.

apoptosis; deciduous tooth; permanent tooth; odontoblast; pulp.

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