DENTAL, HARD TISSUE DESTRUCTION 149 



Remineralization 



The theoretical concept of redeposition of minerals in partially 

 demineralized enamel has been reappraised on the basis of recent 

 observations on radioisotope exchange reactions between enamel 

 and saliva in primate teeth. Experimental application of acid to the 

 enamel surface of teeth in vivo resulted in demineralization in depth 

 beyond what can be detected by gross inspection or by surface rep- 

 lica techniques. In the living animal the demineralization has a 

 definite preferential pattern along the incremental lines of Retzius 

 before grossly visible loss of surface contour. In the normal animal 

 these areas of demineralization appear to be prone to redeposition 

 of minerals, demonstrable within a week or two. However, despite 

 the regained high microdensity, these remineralized areas appear to 

 contain an organic substance which has a greater dye-binding ca- 

 pacity than intact mature enamel. It is believed that enamel in 

 which minerals are redeposited following experimental demineraliza- 

 tion is not completely reconstituted to its original form, and that it 

 would be inappropriate to label this mechanism as a "genuine healing 

 process." 



Acknowledgments. This research was supported by a general Institu- 

 tional Research Grant from the National Institutes of Health, and by a 

 Project Research Grant (D-1413) from the National Institute of Dental 

 Research for "Further Studies on Hard Tissue Destruction." 



References 



Andresen, V. 1926. TJie Physiological and Artificial Mineralization of the 



Enamel. Einar Dancke, Oslo. 

 Badanes, B. B. 1930. Sources and clinical manifestations of the oxalates 



as related to dental caries and erosion. Dental Cosmos, 72, 477-490. 

 Bargen, J. A., and Austin, L. T. 1936. Obstipation with long continued 



vomiting: Effect on the teeth. Am. J. Digest. Diseases, 3, 198. 

 Barnicoat, C. R. 1957. Wear in sheep's teeth. New Zealand J. Sci. and 



Technol, 38A, 583-632. 

 Barnicoat, C. R. 1960. Attrition of incisors of grazing sheep. Nature, 185, 



179. 

 Bird, C. K. 1931. Erosion and abrasion of natural teeth: The remedy or 



correlation of these conditions. Dental Cosmos, 73, 1204-1208. 



