In Vivo Dissolution Rate of Enamel in Acid and R.I.D. Index in School Children

Abstract

The present study was undertaken to determine the relationship between the in vivo acid dissolution rate and the Relative Increment of Decay Index (R.I.D. Index) in school children. The dissolution rates on the upper left central incisor and the lower left first molar were determined in vivo in 1981 and in 1983. Then dental caries was examined by the same examiner every six months from the ages of 7 (1981) to 11 (1985).
The R.I.D. Indices of the upper central incisors and the upper and lower first molars were calculated by comparing each examination with the base lines at 7 or 9 years of age. The results were analysed using the sum of sensitivity and specificity.
The results obtained were as follows:
1) The value of the mean-1/2SD was the most effective threshold for the dissolution rate of enamel.
2) In general, the rate of the central incisor was insignificant, but the rate of the lower first molar was meaningful.
3) The increment of dental caries is an important factor when it comes to evaluate a method such as that used to determine the dissolution rate of enamel in acid.