(_c_) =Upper Bicuspids.=--The first bicuspid has usually one root
flattened and more or less longitudinally grooved on its mesial and
distal surfaces. If this grooving is much marked, it results in a
greater or less division of the root into two slender terminations.
Whether such bifurcation exists or not can seldom be determined before
operation and would not modify the method adopted, but the tendency to
this variation should be borne in mind and the lateral movement be very
gently applied. The internal and external surfaces of the root are for
all practical purposes of equal curvature.
The second bicuspid has usually only one root, which is not so flattened
in the antero-posterior diameter as the first. There is also not the
same tendency to grooving or bifurcation of the root as there is in the
first bicuspid.
The blades of forceps for the bicuspids should be equal segments of the
same circle; they should also be bent at an angle with the handles, so
that the latter may clear the lower lip. The forceps shown in fig. 18 is
a useful pattern. In removing an upper bicuspid, the inner blade of the
forceps should be applied first. For severing the tooth from its
attachments a slight inward movement should first be made, followed by
an outward one. If this fails to cause the socket to yield, the inward
movement may again be made, followed by an outward one, and repeated if
necessary. The removal of the tooth from its socket is to be carried out
by force applied in a downward and outward direction. It is well to
remember that the force applied to the inward should always be slight
compared to that used in the outward direction. The removal of bicuspid
roots is carried out in a manner similar to that for the whole tooth.
[Illustration: FIG. 18.]
(_d_) =Upper Molars.=--The first upper molar has three roots, one internal
towards the palate (palatine), and two external (buccal); of the three
the palatine is the largest, sub-cylindrical in form, and often curved.
The two buccal roots are placed in an anterior and posterior position,
the latter being in a plane internal to the anterior one; both these
roots are somewhat flattened, and of the two the anterior is the larger.
The roots of the second molar are similar in shape to the first, but are
usually smaller. The third molar, when normal, has three roots, but very
frequently these are all fused together so as to form an abrupt tapering
cone, the point of which is often curved.
[Illustration: FIG. 19.]
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