Page 114 - My FlipBook

54 THE TECHNICAX, PEOCEDUBES IN FILLING TEETH.

that is arranged with paper slips, Figure 32, for permanent auto-
matic records. Figure 33 represents one of these record slips
bearing the records of three persons of widely different finger
power, one of seven pounds, one of fifteen i^ounds and another
of twenty-seven pounds. The highest record made on this instru-
ment with the pen grasp was thirty-five pounds, made by the late
Dr. J. H. McKellops, of St. Louis. He took the instrument as
nearly as possible as represented in Figure 26, with the wrist and
hand bent as shown, as most men will when making the thrust
downward, and without haste went across the whole page of the
slip with less than one pound variation. If one will think for a
moment, he will certainly realize what an enormous advantage
the possession of this extraordinary finger power gave him over
the average man in doing dental operations, and of the desira-
bility that every dentist cultivate this to the full limit. Much
careful observation has shown conclusively that delicacy in the
accurate control of instrument movement is very generally an
accompaniment of a high degree of finger power.
An experience of over ten years in taking these measure-
ments shows that much increase of finger power, as well as deli-
cacy of movement, can be acquired by careful training, and also
that it is easily lost by careless habits. For instance, a class of
one hundred and sixty students made an average of nine pounds
at the end of their first year, thirteen pounds at the end of the
second year, and seventeen pounds at the end of the third year.
Some of these same young men fell into careless habits and went
backward in finger power. Others gave later tests showing con-
tinued gain of power. One young man who left school with a
power of only ten pounds and failed to gain anything during his
first two years in practice, put himself into careful training in
the use of a correct form of grasp and the full use of his power,
and within six months made twenty pounds as easily as he had
made the ten pounds formerly.
Delicacy of control of movement usually increases with
power of movement. Therefore, from all points this training of
the hand is exceedingly desirable in dentistry. The training is
purely a matter of careful practice with the best form of grasp,
so that the full muscular power of the hand is brought into
exercise some portion of the time each day. The size of the
instrument handle has much less to do with the exertion of force
than most persons seem to think. An instrument handle one-
fourth inch in diameter is large enough, and three-sixteenths will
generally show no diminution. But with anything smaller than