Age estimation from dental attrition and state of dental treatment--by application of the theory of quantification type I.

Purpose : Estimation of age from dental attrition and the state of dental treatment. Method: The condition of the oral cavities of 1,000 men and women above the age of 20 years was investigated. For teeth with observable attrition, the extent of attrition was recorded. For other teeth, the extent of decay or the state of dental treatment was recorded. Then the condition of the teeth was classified into five categories in consideration of the distribution of frequency and the like. Applying HAYASHI'S theory of quantification type 1, numerical values were calculated and assigned to the condition of each of the 28 teeth, excluding the wisdom teeth, for the purpose of age estimation. Finally, a calculation table for estimating the age from dental attrition and the state of treatment was prepared. Result : The multiple correlation coefficient between the estimated age derived from the "estimated age calculation table" proposed by the author and the real age was 0.814. The rate of correct estimation was high for samples in their twenties and thirties, but for people 60 years and above it was not good. The tooth that could be used most effectively was the upper second left molar. Conclusion : The method of age estimation proposed herewith is considered adequate for practical application.