Page 185 - My FlipBook

born with a material constitution of body that renders it
particularly liable to contract the disease ; but it will not have
tuberculosis unless exposed to the tuberculosis organism; it
must contract tuberculosis the same as others, but it con-
tracts it more readily; there is that element in the body juices
and tissues which enables that particular micro-organism to
grow more freely than in other persons. That is what con-
stitutes a hereditary predisposition to disease.
We find in certain famiUes a hereditary predisposition
to caries of the teeth that is strongly marked. If a man brings
his children to you for treatment, and you find that he, or the
mother, or both, have suffered severely in early youth from
caries of the teeth, you may be sure that the children will
likewise. We that almost universally true of
sufifer find
families—that children will be Uke the parents in regard to
caries of the teeth. Not only this ; we find in very many
instances that the first beginning and the order of progress
will be in the same teeth. In some families the bicuspids
first present proximate cavities—the bicuspids and molars.
In another family we will find the first beginnings of caries
in the proximate surfaces of the incisors, and this will go on
from father to child and grandchild. I have followed those
pecuHarities now through four generations of persons and

find these particular characteristics to be hereditary, the
general expression of the progress of decay being similar. I
want you to understand perfectly that it is not a disease of the
teeth themselves, but something acting upon the teeth, in
every instance. It is some peculiar condition of the body
which favors this action of the micro-organisms in the first
instance, and in the second it is a matter of opportunity, de-
pending upon the shapes of the proximate surfaces of the
teeth; and as shapes of countenance and expression of
countenance are transmitted from parent to child, just so the
shapes of the teeth, and surfaces of the teeth are trans-
mitted from parent to child, and we get the conditions of the
tooth surface favorable to the action of caries, in the incisors
in the one family and in the bicuspids and molars in another
family. In this way we account for these, differences in the
manifestations of hereditary decay of the teeth. By study-
ing these conditions carefully you will find advantages de-
rived from it in the treatment of cases in these various fami-

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