Page 37 - My FlipBook

THIRD LECTURE.

The Use of Force in Filling Teeth and Methods for Its
Accurate Study, Consisting flostly of Instru-
mental Demonstrations.

November 28, 1900.
I will speak this morning of the use of force in con-
densing fillings, gold and amalgam. There is perhaps no
other one item in your operating in which you fail more in
your infirmary practice than in the use of force. This is not
peculiar to this class, but it is general with classes in the
study of dentistry, and I may say also that it is common
among practitioners to make grave mistakes in the use of
force in condensing both gold and amalgam fillings. It has
been a difficult subject for study, and until recently we have
had no definite means of studying it accurately. Efforts
have been made heretofore by a number of men to devise
ways and means of studying this subject with accuracy and
to devise means of communicating accurately with one an-
other in regard to the use of force. I remember that Dr.
Gushing spent a great deal of time and study on this subject
and presented a paper embodying his results before the Illi-
nois State Dental Society in 1870. It would be well for you
to look up that article and read it—Gushing before the Illi-
nois State Dental Society, 1870, page 69. You will find it
in the library. With his apparatus, however, the results were
unsatisfactory. In the literature relating to physics there is
nothing on this subject. Encyclopedia Britannica, in speak-
ing of the impact of mallets, hammers, etc., says the subject
has not been accurately studied. Daniels, in his great work on
physics, ventures a few suggestions which are, as he says,
suppositions. Most others have passed the subject entirely.
Some give studies under the heading "Impact," but when
we come to look through their articles we find that it is
impulse instead of impact that they have studied, and that
subject has been studied very closely. Impulse is the motion
given to the object struck, not the pounds pressure exerted
between the mallet and the object struck. What we want is
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