CALCIUM, PHOSPHORUS AND CARBON DIOXIDE DETERMINATIONS ON ALL THE DENTIN FROM SOUND AND CARIOUS TEETH

¹ Department of Chemistry, College of Arts and Sciences and the Department of Biochemistry and Pharmacology, School of Medicine and Dentistry, University of Rochester, Rochester, New York

1. All the dentin from each of 60 teeth (taken from 3 patients), analyzed for Ca, P and CO₂, gave the following averages plus or minus the standard deviations: Ca—35.34 ± 0.74, P—17.09 ± 0.44, and CO₂—3.98 ± 0.38 (based on inorganic weights).

2. When the values for the teeth of the 4 caries classes were analyzed and compared, it was evident that Ca and P values exhibited a "remarkable constancy," showing no tendency to change with increasing degree of caries. The CO₂ values tended to increase from caries class 0 to class 2, but the differences are not statistically significant.

3. Evidence is brought out to show that the principal inorganic component of dentin is probably hydroxylapatite, the carbonates presumably being adsorbed, occluded or interstitially crystallized.