CHANGES IN THE VOLUME PER CENT OF MOISTURE, ORGANIC AND INORGANIC MATERIAL IN DENTAL CARIES
RICHARD S. MANLY PH.D.1 and
MARTIN L. DEAKINS D.D.S., M.S.1
1 Department of Biochemistry and Pharmacology, School of Medicine and Dentistry, The University of Rochester, Rochester, New York
Microdeterminations of volume, water, organic and inorganic constituents have been carried out on normal dentin and certain parts of carious dentin lesions. When calculated on the volume percentage basis the results indicate that there are 3 physically and chemically distinct zones within the carious area, which are characterized by 1—normal hardness and a decrease in organic volume amounting to 
of the original; 2—softening and inorganic loss varying from 
to 
of the original with but slightly decreased and constant organic volume; and 3—sponginess and major losses of both organic and inorganic material. In all zones a gain in moisture compensated for the volume losses in the other 2 constituents.
