Page 262 - My FlipBook

erosions were cut out by an acid. I made a very considerable
laboratory experiment upon that a number of years ago to de-
termine whether or not that was possible. I did succeed in
producinc^ the characteristic appearances of an erosion by the
action of acid in motion in cutting away the teeth, but the con-
ditions required for that were so different from anything we
can conceive of as being applied in the mouth as to render it
certain that erosion in the mouth is not caused in that way. It
required a very rapid motion of the fluid, and that it break over
the teeth in a certain way in order to produce this characteristic
smooth cutting, leaving the surface hard, instead of softening,
as we usually get it with acids ; so that we cannot conceive of
it being done in that way. Another hypothesis that has been
prominent has been that certain mucous follicles of the lip
that come in contact with the surface of the teeth are in a
more or less diseased state and emit an acid secretion that cuts
away the teeth, and persons who have written upon this subject
have cited case after case in which there was a more or less
reddened portion of the mucous membrane that seemed to fit
very accurately into the eroded surface. Well, I have seen
that in a number of cases, and in those particular cases it would
seem to be a very plausible explanation, but I have seen many
cases that showed nothing- of that kind whatever, and also a
case which I mav relate where there were no mucous surfaces
which came in contact with the eroded surface. This occurred
in a little girl who had had a burn upon the side of her face
in which the tissues of the cheek and lip were destroyed and the
teeth were without the covering of the lips, and yet the sur-
faces of those teeth that were exposed in that way were eroded
in the dish-shaped forms that I have passed among you, and
so sensitive that the little girl would almost flinch if I looked
at her ; anything that would touch them seemed to terrify her.
\\'e were making plastic operations for the improvement of the
mouth, and these sensitive surfaces worried the little girl so
much that I finally extracted the teeth. The saliva was con-
tinually drooling over those teeth, but there was no tissue
coming in contact with them. In cases in which erosion oc-
curs upon the proximate surfaces of teeth there is no mucous
membrane coming in contact with them. I remember very
well one case that I had under observation for many years,
beeinninsr in the mouth of a healthv vouth, in which the teeth

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