Abstract
For the purpose of investigating morphological changes of the child gingival epithelium during resorption on the roots of deciduous teeth, a total of 52 clinically normal gingivae, obtained from subjects ranging in age from 3 to 7 years were examined. The subjects were devided into 4 groups depending on the stage of the root resorption. The sample gingivae were examined by the ultrathin section method. The following were the results of the present investigation.
1) The pedicles, present at the basal surface of the basal cells and extending toward the connective tissue, grew in size along with the root resorption. Because these changes were attended with an increase in the number of the hemi-desmosomes as well as the anchoring fibrils, the root resorption may have strengthened the cohesion between the basal cells and the connective tissue.
2) Many tonofilament bundles and melanosomes were observed in the cytoplasm of the basal cells in the later stages of the root resorption.
3) Less developed cytoplasmic projections were observed in the spinous cells of the child gingival epithelium, and the intercelluler space of the spinous layer was relatively narrower than those of adults. The intercelluler space, however, was enlarged in the later stages of the root resorption, and the intercelluler junctions were the least well defined in this stage.
4) Odland bodies of the granuler cells increased in number with the root resorption. Especially in the later stages of the root resorption, Odland bodies were observed in the cells of the lower cornified layer, and discharged the characteristic lamellated structures into the intercellular spaces of the lower cornified layer. It was suggested that the increase of the Odland bodies in the later stages of the root resorption correlated to the spread of the intercellular spaces of the basal and the lower spinous layer in this stage.
5) Dense homogeneous deposits were observed in the granular cells, but no morphological changes were seen with the root resorption.
