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T
MICROSCOPICAL PHENOMENA OF DECAY. 165
The carious dentine had accordingly lost on the whole seven-
ninths of its original mass, the lime-salts had lost twelve-thir-
teenths, and the organic matter two-fifths.
In plain words, the carious dentine had suftered an almost
complete decalcification, onlv one-thirteenth of the original
amount of lime-salts being still present. The organic matter
had suffered the comparatively small loss of two-fifths of its
original amount. This loss is no doubt attrilmtable, for the
most part, to the direct action of the micro-organisms upon the
more completely decalcified portions of the carious dentine.
The results of these experiments are too plain to require fur-
ther explanation. They show an almost complete decalcification
of the carious dentine, and a comparatively small reduction of
the oro-anic matter, also that the oro;anic matter vields last to the
destroying agents.
microscopical phenomena of decay.
1. Decay of the Enamel-Cuticle.
If we subject a piece of Nasmyth's membrane perforated by
decay to a microscopic examination, we will find, in addition to
its discoloration and clefts,
an enormous number of
round and oblong densely
crowded bodies, which are
easily recognized as bacte-
ria, especially after staining
(Plate, Fig. 6). They are
sometimes so closely packed
that the membrane itself is
entirely lost to sight (Fig.
Small piece of Es-AMEL-CrTicLE
62). iVedl calls these cor-
^ Converted into a mass of bacteria by decay. 300:1.
^ - • r-
puscles " the matrix oi Lep-
tothrix buccalis." They have, however, most probably no ne-
cessary genetic connection with thread-forming mouth-bacteria,
but represent various kinds of bacteria, both monomorph and
pleomorph. They exert the same destructive influence upon the
enamel-cuticle as upon every organic substance ; it loses its
transparency, ap[»ears thickened and cleft in all directions, and
MICROSCOPICAL PHENOMENA OF DECAY. 165
The carious dentine had accordingly lost on the whole seven-
ninths of its original mass, the lime-salts had lost twelve-thir-
teenths, and the organic matter two-fifths.
In plain words, the carious dentine had suftered an almost
complete decalcification, onlv one-thirteenth of the original
amount of lime-salts being still present. The organic matter
had suffered the comparatively small loss of two-fifths of its
original amount. This loss is no doubt attrilmtable, for the
most part, to the direct action of the micro-organisms upon the
more completely decalcified portions of the carious dentine.
The results of these experiments are too plain to require fur-
ther explanation. They show an almost complete decalcification
of the carious dentine, and a comparatively small reduction of
the oro-anic matter, also that the oro;anic matter vields last to the
destroying agents.
microscopical phenomena of decay.
1. Decay of the Enamel-Cuticle.
If we subject a piece of Nasmyth's membrane perforated by
decay to a microscopic examination, we will find, in addition to
its discoloration and clefts,
an enormous number of
round and oblong densely
crowded bodies, which are
easily recognized as bacte-
ria, especially after staining
(Plate, Fig. 6). They are
sometimes so closely packed
that the membrane itself is
entirely lost to sight (Fig.
Small piece of Es-AMEL-CrTicLE
62). iVedl calls these cor-
^ Converted into a mass of bacteria by decay. 300:1.
^ - • r-
puscles " the matrix oi Lep-
tothrix buccalis." They have, however, most probably no ne-
cessary genetic connection with thread-forming mouth-bacteria,
but represent various kinds of bacteria, both monomorph and
pleomorph. They exert the same destructive influence upon the
enamel-cuticle as upon every organic substance ; it loses its
transparency, ap[»ears thickened and cleft in all directions, and
