Page 300 - My FlipBook

166 PATHOLOGY OF THE HAED TISSUES OF THE TEETH.
the custom in most of the smaller cities up to the time when it
was supplanted by the cold storage meats prepared by the great
packing houses, which have now almost universally taken the
place formerly occupied by the local butchers. These meats
are crushed at from one-fourth to one-third less number of
pounds than fresh meats, and they are sometimes even softer
than this figure, when tried with the same instrument under
otherwise the same conditions.
A similar change to softer foods is found in every direction.
Gardeners are vying with each other in the selection and culti-
vation of the tenderest vegetables possible in the effort to satisfy
the general demand of our people for tender foods.
Some of the confections are so hard as to be dangerous to
the cusps of teeth that have become weakened by caries.
Crystals of rock candy crushed at 30 to 50 pounds.
Lemon tablets crushed at 50 " 70 "
Hard candy (stick), old, crushed at 90 " 120 "
Hard candy (stick), fresh, crushed at 45" 60 "
Small cinnamon drops crushed at 30" 60 "
Some gum drops which were mashed out of shape at twenty
to thirty pounds offered great resistance when wedged in between
the cusps. Indeed, it often would happen that these could not
be completely crushed with less than 250 pounds. Small sticks
of licorice offered similar resistance. These and similar articles
prove dangerous to the cusps of teeth that are weakened by
caries, or to bridges or artificial crowns. In the construction of
these great care as to strength should be used. Bread crusts
are equally dangerous. Indeed, within my personal observation,
more teeth that seemed sufficiently strong have been broken
with bread crusts — and not over-hard crusts either — than
with any other one thing. I used sometimes to feel that persons
relating these accidents were not quite honest in their state-
ments, but when I tried the bread and found that it would wedge
in between the cusps of the teeth and not be crushed out with a
force of 350 pounds, I changed my mind.
Some persons have objected to my findings on a number
of these points because only the direct up-and-down motions
were used in tests; claiming that if the lateral or grinding
motion were used the crushing would have been accomplished
with much less force, and especially that if bread crusts are
first wet with water or the saliva they would crush easily. All
of this is perfectly correct. Eock candy or lemon drops will melt
away in the mouth if the person does not bite upon them, and