Ultrasructural observation of rat gingival epithelium.

Abstract

An ultrastructural study on rat gingival tissue was made, with particular attention to the junctional and sulcular epithelium. The animals used were 6 to 7 week-old male Wistar rats. The results were as follows: 1.The epithelium facing the tooth could be divided into 3 anatomical regions, i.e.,1)the sulcular region, 2)the junctional region, and 3)the transitional region between them. Furthermore, the junctional epithelium could be sub-divid into 3 areas, namely, the coronal side area, the apical side area, and the intermediate area between them.

2. The sulcular epithelium showed the histoarchitecture to be similar to that of the keratinized stratified squamous epithelium.

3.The junctional epithelium showed the structure of nonkeratinized stratified squamous epithelium, while the intercellar space contained many neutrophilic leukocytes, a few lymphocytes and Langerhans like cells. The coronal side area of the junctional epithelium showed partial degeneration, desqamation, and necrosis. The thickness of the junctional epithelial layer gradually decreased on the apical side area.

4.The basal cells of the transitional region between the sulcular and junctional epithelium were found to be tall and cylindrical in shape.

5.The histological significance of the above-mentioned findings are also discussed.