Ultrastructure of the Natal and Primary Teeth

Abstract

Abstract Aim: The teeth present in the oral cavity at birth are known as natal teeth and their etiology is still unknown. In this study, we aimed to compare the morphologic structures of natal and primary teeth at the ultra structural level using transmission electron microscope (TEM). Material and Methods: We investigated a natal tooth of a fourteen-day-old newborn baby. It was extracted due to the hypermobility with a risk of aspiration. As a control, a healthy primary incisor tooth was extracted from another child due to the physiologic root resorption. Immediately after extraction, both teeth were fixed in 10% formalin solution and decalcified by immersion in ethylenediaminetetraacetic acid (EDTA) solution. Following routine TEM preparation process, teeth were embedded in Epon 812. Results: Histologically, structures of enamel prism and dentin tubules were different in the natal tooth compared to the primary tooth. Light microscopic (LM) and TEM investigations of the primary tooth showed prominent crystal structures in the enamel prism and regular organization in both enamel and dentin. LM and TEM investigations of the natal tooth revealed an irregular enamel prism in the hypoplastic enamel, vacuolization in the interprismatic enamel and an irregular organization in the dentin tubules. Conclusion: We conclude that the structural differences of the enamel and dentin in the natal tooth might be a result of incomplete maturation.