GLYCOGEN AND CARBOHYDRATE—PROTEIN COMPLEX IN DEVELOPING TEETH OF THE RAT

¹ Department of Orthodontia, College of Dentistry, and Department of Pathology, College of Medicine, University of Illinois, Chicago, Ill.

1. Glycogen was found to occur in the Malpighian layer of the oral epithelium, in the dental lamina, and at varying times in the outer enamel epithelium, stellate reticulum, and stratum intermedium of the developing rat tooth. The ameloblasts and odontoblasts and pulp of the incisor contained this substance in the early stages. In a few instances, glycogen was found in the odontoblasts and pulp of the molar.

2. The cement substances between the ameloblasts contains a glycoprotein.

3. Glycoprotein material was observed in the cells of the outer enamel epithelium, stellate reticulum, stratum intermedium, and in the processes of the connective tissue pulp cells.

4. Glycoprotein granules were observed to appear in the cytoplasm of the odontoblasts and the ameloblasts in the stages preliminary to the formation of dentin and enamel.

5. The dentin was shown to contain a carbohydrate-protein complex.

6. The demonstration of an acid-soluble carbohydrate-protein complex as one of the components of developing enamel matrix is regarded as particularly significant for the understanding of the pathogenesis of dental caries.