Page 301 - My FlipBook

THE FOKCE USED IN MASTICATION". 167

bread crusts will become soft. But the trouble is, that people
will bite upon them and bite very hard before they have become
wet. Certainly persons may use the grinding motion on bread
crusts, and these, being brittle, will crush easily, but the fact
is people are not always careful to do this. Therefore, for the
purpose intended, the manner of trial and the results given
must stand as correct.
The dentist should give warning to such of his patients
as have had their teeth weakened by caries, about biting on any
of those things that are liable to become wedged between cusps
and split them off. It is his business to know these dangers and
to give the necessary instruction to bring his patients to under-
stand the nature of these dangers to the teeth. He should also
guard weakness of cusps closely in his manner of preparation
of cavities and placing of fillings that they may stand the
severest stress possible. All that we have learned of these
points urge this course in the strongest terms. But those whose
teeth are perfect need no warnings against the full use of any
of the things used as foods. They should only avoid reckless-
ness in biting upon the harder metals, pebbles and things of a
similar nature, which occasionally are mingled with food by
accident. The hazelnuts that formerly grew wild all over the
Western States generally required from 150 to 200 pounds to
crack them. The boys, many of the girls, and grown folks, too,
used to crack them with their teeth as a regular habit. Many a
laugh was had on seeing a boy with one of these hard nuts between
his teeth, all of the muscles of his body in tension, both hands on
the lower jaw helping; yet with all of this effort no perfect
teeth were broken. The hazelnut modified by cultivation— the
filbert that we get nowadays, is broken with less than half the
force required by the wild hazelnuts. Any one whose teeth have
not been weakened by caries should be able to crack filberts with
perfect freedom. If the peridental membranes have not become
weakened by failure of proper use, it should be a pleasure to
chew the hardest of ordinary foods.
The cleaning power of vigorous mastication is greater and
better than artificial cleaning. It does much for the health of
the teeth and the membranes about them and contributes to the
general health and vigor of the whole person. Therefore it
seems to be the duty of the dentist to cultivate this in his com-
munity by careful advice to his patients as he meets them pro-
fessionally whenever he observes that the teeth are insufficiently
used.