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164 THE MICRO-ORGANISMS OF THE HUMAN MOUTH.
parative losses of the organic and inorganic constituents of the
dentine.
A large number of analyses were made by myself, as well as
by Dr. Jeserich, Prof. Liebreich, and others, in which decayed
dentine was compared with dentine softened in a fermenting
mixture of saliva and bread and in various acids. The results
obtained showed the process to be identical in all cases. (See
Dental Cosmos, 1883, p. 337.) In order to obtain results which
would show at the same time the amount of loss suffered by the
organic constituents of the dentine, I proceeded in the following
manner
I procured three perfectly fresh teeth which contained large
quantities of carious dentine. These teeth were washed in a
gentle stream of water to remove all remains of food, and the
softened dentine removed in one piece with a spoon-shaped exca-
vator. The joint volume of the pieces was then determined by
an instrument specially constructed for the purpose, which gave
the volume at once in cubic millimeters, and also by the ordi-
nary picnometer. Then (from the same teeth) pieces of sound
dentine were procured whose volume was determined in the
same manner. The pieces were then dried for thirty hours at
105° C, and analyzed.
I give the result of one analysis
187.2 cubic millimeters of sound dentine weighed 0.3600
" " " " carious " " 0.0821
Loss, 0.2779
The sound dentine gave on analysis 72.1 per cent.
lime-salts = 0.2595
The carious dentine gave on analysis 26.3 per cent.
lime-salts = 0.0192
Loss, 0.2403
The sound dentine contained 27.9 organic matter ;= 0.1004
" carious " " 73.7 " " =0.0605
Loss, 0.0399
:
164 THE MICRO-ORGANISMS OF THE HUMAN MOUTH.
parative losses of the organic and inorganic constituents of the
dentine.
A large number of analyses were made by myself, as well as
by Dr. Jeserich, Prof. Liebreich, and others, in which decayed
dentine was compared with dentine softened in a fermenting
mixture of saliva and bread and in various acids. The results
obtained showed the process to be identical in all cases. (See
Dental Cosmos, 1883, p. 337.) In order to obtain results which
would show at the same time the amount of loss suffered by the
organic constituents of the dentine, I proceeded in the following
manner
I procured three perfectly fresh teeth which contained large
quantities of carious dentine. These teeth were washed in a
gentle stream of water to remove all remains of food, and the
softened dentine removed in one piece with a spoon-shaped exca-
vator. The joint volume of the pieces was then determined by
an instrument specially constructed for the purpose, which gave
the volume at once in cubic millimeters, and also by the ordi-
nary picnometer. Then (from the same teeth) pieces of sound
dentine were procured whose volume was determined in the
same manner. The pieces were then dried for thirty hours at
105° C, and analyzed.
I give the result of one analysis
187.2 cubic millimeters of sound dentine weighed 0.3600
" " " " carious " " 0.0821
Loss, 0.2779
The sound dentine gave on analysis 72.1 per cent.
lime-salts = 0.2595
The carious dentine gave on analysis 26.3 per cent.
lime-salts = 0.0192
Loss, 0.2403
The sound dentine contained 27.9 organic matter ;= 0.1004
" carious " " 73.7 " " =0.0605
Loss, 0.0399
