Page 205 - My FlipBook

eradication and cure, and with the view of prevention. After ;
decay has once begun in the substance of a tooth the only
treatment that has thus far been found effective in preventing
its progress or in curing the decay has been the complete
removal of all of the carious area and the filling of the cavity
with metal, or with some substance that is durable. Thus far
gold holds the first place for filling teeth; amalgam the second
place. There are a few persons who would place tin second
certainly I should not. Besides these two, there are in use
tin, gutta-percha and the cements, these latter more es-
pecially for temporary fillings. In the use of this treatment
we would seem to be violating some of the general principles
of physiology and pathology. Certainly we cannot place any
of these substances in the soft tissues without causing more
or less irritation ; there will be a reaction against the presence
of a foreign body, whether it be in the soft tissues or in the
bone. Any plug that we may place in a living bone will be
loosened by absorption about it within a short time. If we
drill into the bone for the purpose of attaching apparatus for
holding the ends of a fractured bone together and place gold,
silver, iron, or what not, into the bone, we find that thev will
hold for only a short time ; absorption will occur about them
and they will be loosened. In the teeth it is different. No
irritation is produced in the dentin by a process of this kind,
except such an irritation as is produced by cutting the denti-
nal fibrils in the preparation of the cavitv. No absorption of
the dentin occurs about the filling. There is no vascular sys-
tem that is interfered with ; there are no physiological changes
occurring in the hard tissues of the tooth. The onlv changes
of this kind occurring in the teeth are the changes in the sen-
sations of which I have been speaking, and these changes in
the sensory function do not involve changes in the hard tis-
sues of the tooth. Do what we may, we fail to bring about
any absorption of lime salts or any deposit of lime salts in
the substance of the tooth. Now, there is this difference in
the physiological condition of teeth, as compared with the
physiological condition of bone, that enables us by the in-
sertion of fillings to make an artificial repair of this injury.
If we had the same conditions as to the circulation, or the
disposition to absorption that is manifested in bone through
the system of Haversian canals, it would be impossible for us

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