Summary
Maturation ameloblasts of developing molar teeth of the rat were studied by both scanning and transmission electron microscopy. After fixation, teeth were frozen and split. One face of the fractured tooth was used for SEM, the other for TEM.
It was found that in some regions proximal junctional complexes separate the interameloblast space from the intercellular space of the papillary layer. Thereby an intercellular ameloblastic compartment is delineated which in some specimens contains a substance interpreted to be colloidal. Elsewhere the proximal junctions of ameloblasts are not present and free communication between the extracellular spaces is evident. The apical pole of ameloblasts varies in structure. Over some areas there is a distinct distal border zone with membranous infoldings which in some regions resembles a striated or ruffled border, but in other regions the membranes show whorl configurations. The distal border zone also contains granules with flocculent material. Elsewhere the ameloblasts display no distal border zone and the cells show a smooth membrane (except for pinocytotic vesicles and hemidesmosomes) facing the enamel surface. The lateral surface of ameloblasts exhibits a variety of surface configurations similar to but not as pronounced as those reported previously in rat incisor maturation ameloblasts.
Similar content being viewed by others
References
Boyde, A., Bailey, E., Jones, S.J., Tamarin, A.: Dimensional changes during specimen preparation for scanning electron microscopy, pp. 507–518 In: Scanning Electron Microscopy/1977. O. Johari and R. Becker (eds.) Chicago: Illinois Institute of Technology Research Institute, 1977
Boyde, A., Reith, E.J.: Scanning electron microscopy of the lateral surfaces of rat incisor ameloblasts. J. Anat. 122, 603–610 (1976)
Boyde, A., Reith, E.J.: Scanning electron microscopy of rat maturation ameloblasts. Cell Tissue Res. 178, 221–228 (1977)
Josephsen, K., Fejerskov, O.: Ameloblast modulation in the maturation zone of the rat incisor enamel organ. A light and electron microscopic study. J. Anat. 124, 45–70 (1977)
Kurahashi, Y., Nagai, N., Watanabe, K., Watanabe, H., Yama, K.: Chronological observation of the odontogenesis of rat molars. Bull. Tokyo Dent. Coll. 9, 147–159 (1968)
Marsland, E.A.: A histological investigation of amelogenesis in rats. I. Matrix formation. Brit. Dent. J. 91, 251–261 (1951)
Marsland, E.A.: A histological investigation of amelogenesis in rats. II. Maturation. Brit. Dent. J. 92, 109–119 (1952)
Reith, E.J.: The stages of amelogenesis as observed in molar teeth of young rats. J. Ultrastruct. Res. 30, 111–151 (1970)
Author information
Authors and Affiliations
Additional information
The authors wish to thank Pauletta Sanders and Helen Ruane for technical assistance. This project was supported in part by USPHS NIH Grant DE04059-03 and by the Medical Research Council of Great Britain
Rights and permissions
About this article
Cite this article
Reith, E.J., Boyde, A. A correlated scanning and transmission electron microscopic study of maturation ameloblasts in developing molar teeth of rats. Cell Tissue Res. 197, 421–431 (1979). https://doi.org/10.1007/BF00233567
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00233567