Fluoride Concentration and Dental Caries in Two Ancient Populations

Objective: The purpose of this research is to determine the caries prevalence of two separate ancient cultures within present-day Chile and to compare those analyses with the enamel fluoride concentration of these same two populations. Method: Using the results from the Nuclear Reaction Analysis (NRA) technique in determining enamel fluoride concentration, it had previously been determined that the Chinchorro (5860-1720 B.C.) had approximately two times the fluoride concentration in enamel than the Maitas-Chiribaya (850-1000 A.D.). With caries data recorded from the mummies whose teeth were analyzed for fluoride concentration, it was possible to determine the relationship between enamel fluoride concentration and dental caries in these two ancient populations. Results: Of the 772 teeth examined from the Chinchorro mummies, only 14 teeth (15 surfaces) were found to be carious (75% affecting pit and fissures and 25% involving smooth surfaces). From the Maitas-Chiribaya population, 860 teeth were examined resulting in 132 carious teeth or 384 surfaces. Thirty percent of the carious surfaces involved occlusal surfaces, while 70% affected smooth surfaces. While < 2% of Chinchorro teeth exhibited caries, over 15% of Maitas-Chiribaya teeth were carious (p<.05). Furthermore, the proportion of pit and fissure vs smooth surface caries was as expected with Chinchorro mummies having predominately pit and fissure caries and the teeth of Maitas-Chiribaya exhibiting predominantly smooth surface caries (p < .05). Conclusion: The teeth of these two ancient populations with differing enamel fluoride concentration reinforce the importance of fluoride in preventing caries in an environment devoid of other factors. The study was funded by Case Western Reserve University School of Dentistry, Cleveland, OH.