Abstract
The reduced enamel epithelium transforms into a stratified squamous epithelium, i.e. a junctional epithelium, as the tooth erupts. In this study, we observed apoptosis in the reduced enamel epithelia of rats just after tooth eruption and before complete junctional epithelium formation, by the TUNEL method and electron microscopy. TUNEL-positive reactions were scattered in the reduced ameloblasts and in the external cells of the reduced enamel epithelium. Electron microscopic observation confirmed features of apoptosis, such as nuclei with chromatin condensation, cell shrinkage, and phagocytosis of apoptotic bodies by macro-phage-like cells and epithelial cells. These results suggest that apoptotic cell death is involved in the disappearance of reduced ameloblasts and the external cells of the reduced enamel epithelium during the formation of the junctional epithelium.
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References
Schroeder, H.E. andListgarten, M.A.: Fine structure of the developing epithelial attachment of human teeth.In: Monographs in Developmental Biology Vol. 2 (Wolsky, A. andTarrytown, N.Y. ed.), p. 15–81, Karger Verlag, Basal, 1977.
Abiko, Y., Kanno, H., Arai, J., Nishimura, M., Saito, M. andKaku, T.: Apoptotic cell death at tooth eruption in rat molar observed byin situ labeling of nuclear DNA fragmentation.Jpn. J. Oral. Biol. 37, 488–492 (1995).
Gavrieli, Y., Sherman, Y. andBen-Sassa, S.A.: Identification of programmed cell deathin situ via specific labeling of nuclear DNA fragmentation.J. Cell Biol. 119, 493–501 (1992).
Majino, G. andJoris, I.: Apoptosis, oncosis, and necrosis. An overview of cell death.Am. J. Pathol. 146, 3–15 (1995).
Shibata, S., Suzuki, S., Tengan, T. andYamashita, Y.: A histochemical study of apoptosis in the reduced ameloblasts of erupting mouse molars.Arch. Oral Biol. 40: 677–680 (1995).
Lange, D. andSchroeder, H.E.: Cytochemistry and ultrastructure of gingival sulcus cells.Helv. Odotol. Acta,15, 65–86 (1971).
Ghadially, F.N.: Diagnostic Electron Microscopy of Tumours. 2nd ed., p. 326–333 Butterworth, London, 1985.
Hume, W.J.: Perspectives on Mammalian Cell Death (Potten, C.S. ed.), p. 73–79. Oxford University Press, Oxford, 1987.
Glaso, M., Sandiv, K.U. andHaaskjold, E.: Apoptosis in the rat corneal epithelium during regeneration.APMIS,101, 914–922 (1993).
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Abiko, Y., Nishimura, M., Arai, J. et al. Apoptosis in the reduced enamel epithelium just after tooth emergence in rats. Med Electron Microsc 29, 84–89 (1996). https://doi.org/10.1007/BF02349044
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DOI: https://doi.org/10.1007/BF02349044