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TWENTY-THIRD LECTURE.
Absorption of Roots of the Deciduous Teeth—Continued.

At the close of my last lecture I was talking of the ab-
sorption of the roots of the temporary teeth and the acci-
dents that occur in connection with it. I have a few more
words to Siay on that subject.
The absorptive process seems to be very fickle in its
beginning and in its progress, and there are many ca&es of
variation from the normal. In some of these the absorptive
process seems to be hurried and it will be completed before
the normal time so that a temporary tooth will drop away be-
fore the permanent tootih has come forward, and the child may
be without a tooth for la year or a year and a half ; whereas^
in the normal process, when the little tooth drops away, the
permainent tooth sihould be presented at once. These cases
are not so frequent, however, as delayed absorption. De-
layed absorption of roots occurs quite often, so that the
coming tooth will be deflected from its position.
If the absorption of a root of an incisor or cus-
pid is delayed the coming tooth will generally strike
its lingual surface and be deflected to the lingual. I do not
care to gO' into this farther than mentioning the fact as it
belongs really to orthodontia. Occasionally the cuspid tooth,
if the absorption of the root is delayed, will be deflected to
the labial, so that it will stand to the labial of its normal posi-
tion. In case of the bicuspids, the crowns are nor-
mally between the spreading roots of the deciduous molars,
and in case the absorption is delayed generally the coming
bicuspid is simply held back. In the upper jaw it may es-
cape from between the spreading buccal roots and be de-
flected to the ibuccal, so' that the tooth will come out to the
buccal of its normal iposition in the arch. In the lower jaw
they may be deflected either to the buccal or to the lingual,
but they are more g^enerally simply delayed, held back by
the lack of absorption of the roots. Indeed, the absorption
of the roots of the temporary teeth does not seem to be
especially stimulated by the coming of the permanent teeth,
for they are often absorbe;d wdien there is no permanent tooth

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