Page 237 - My FlipBook

roots of teeth between different individuals. Some will be ;
year or so early or as much late. Also, the time between
the individual teeth of the person may be considerable. I
think that perhaps this four and five years for the central
and lateral is not quite the average ; four and four and a
half would ibe more nearly the average, but this is a figure
that is easily remembered and I have placed it in that way.
Occasionally I have seen the lateral incisors falling away
before the centrals, but that is rare. Often we will see them
falling away about the same time, or very close together
not six months between. Often again there will be
two years between. With the molars it is the same way.
Often we will see the second bicuspid in place before the
first bicuspid. All of these differences you may find. It
does not run absolutely as I have represented here, but
this must be taken to represent an average from which
there is a pretty wide variation.
There are a number of what we may call accidents
occurring during this absorption of the roots of temporary
teeth. First, if there is an alveolar abscess at the root of
a temporary tooth and that abscess is continuing in a
chronic form, the rule is that absorption of the root will
fail. The death of the pulp of the tooth does not interfere
with the absorptive process. The question is simply as to
the condition of the tissues about the end of the root. The
absorption of these roots is a physiological process, and in
order for it to progress properly the tissues about the root,
the peridental membrane, must be in a physiological con-
dition. If disease is going on there, such as we have in
alveolar albscess, the absorptive process will be defeated and
different kinds of trouble come up on account of it. Often
the teeth are bodily pushed out of the way, the other tooth
taking its place in spite of them. In other cases the perma-
nent tooth is deflected from its proper position. The roots
of incisors are occasionally pushed labially, causing the end
of the root to protrude through the gums, and sometimes into
the lip of the child. We see cases in the infirmary now and
then ; these cases are not very frequent, and yet they are
sufihciently frequent so that we should all know them when
they are presented to us (making drawing on board). In
case of alveolar abscess the bone about the end of the root

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