Page 195 - My FlipBook

facts observed ; the difficulty was in the faulty interpreta-
tion of those facts. Now, this is a difficulty that is com-
mon; it is common to all men in all the walks of life; we
may observe facts correctly and fail to interpret those facts
correctly, and thus arrive at deductions wholly at fault.
This is one of the difficulties in progress. It is one of the
reasons why the German bacteriologists, for instance, have
said so constantly that they would report facts and facts
only and leave out the deductions. We may go too far in
that direction as well, for a deduction that explains a fact
is important ; a thinkable, explanation is better than no ex-
planation at all, even if we do run some risk of going
wrong. Other facts will be developed that will finally cor-
rect our deductions and put us again upon the right track.
In these ways we progress little by little, year by year.H''

Vital Phenomena in Caries.
It has been held that the teeth being vital, vital influ-
ences played a very important part in caries. I need not
spend much time with this, for it is an old notion that has
been gradually passing away from the minds of dentists for
the last seventy-five years. You have seen yourselves that
teeth that have lost their pulps, and in which the dentin is not
vital, decay the same as teeth that have living pulps. There
is no difference in the character of the decay; the one decay
is the same as the other. Some persons have claimed that
teeth with living pulps decayed more rapidly than teeth with
dead pulps ; others have claimed that teeth with dead pulps
decayed more rapidly. My own notion has been that those
with dead pulps do 'decay rather more rapidly, but the dif-
ference is so little that men differ in their notion in regard
to that ; it is not a matter of very great importance.
One thing that broke down the notion that vital influ-
ence was causative in caries of the teeth was the habit of
planting human teeth as pivot teeth on roots, or fastening
human teeth on carved ivory plates, or fastening human
teeth on gold plates as artificial substitutes. It was found
that these teeth decayed the same and in the same locaUties
as the living teeth in the human mouth. Of course, these
observations were in themselves sufficient to break down
the notion that vital influences materially affect caries of
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