Page 168 - My FlipBook

166
experience has enabled me to judge, always attacks the
crown of the tooth, and never the neck or the root.
As the disease is more actively resisted by the greater
vascularity, and consequent activity of the internal bony
structure, than by the harder and less vital external parts of
the tooth, it never proceeds so far towards the cavity con-
taining the nerve, as to render this membrane altogether
unprotected by the bony structure, before it has penetrated
through the external osseous part including the enamel, and
has thus formed a natural outlet for the bony abscess.
Mr. Fox and other writers assert, that they have seen ca-
ries sometimes produce idiopathic inflammation in the living
membrane, and the death of the tooth, before the disease has
penetrated through the external surface of the crown ; but I
am perfectly assured of the contrary, because it is in oppo-
sition to the principles of that chemical action, to which the
tooth is exposed, when affected by this disease, and against
all accurate observation and experience. See Fox's Nat.
Hist. 6(-c. Part II. page 14.
The cases which have given rise to this opinion, have not
been considered with sufficient accuracy ; this has arisen
either from the difficulty of discovering the carious cavity,
or from erroneously attributing the death of the tooth to the
effect of caries, when it has been produced, perhaps by some
mechanical irritation, an accidental blow, clumsy operation,
or great irregularity in the situation of a tooth, &c. ; in con-
sequence of which, an inflammation and mortification of the
membrane has taken place before its extraction.
1 have already explained the great difference in the effect
produced by the chemical influence of dead or carious mat-
ter upon the living bony structure, and that upon a tooth
already destitute of life ; a fact, however, totally disregarded,