Page 796 - My FlipBook

704 ORTHODONTIA AS AN OPERATIVE PROCEDURE.

drawn up to a normal jxjsition l)y the use of liuaturos which were
h)(i|)C(l around the bicuspids and niohirs, and fastened at the lingual
surliice, then tied to the masticating surface of the l)ridge above." '
Fig. 813 shows an appliance of similar character devised In- Dr.
C. S. Case.^ The object of the appliance is to depress the lower incisors
in their sockets, and raise the bicuspids, and first molar also, when
possible, so as to change the whole line of occlusion and open the bite.
On each molar—first or second according to the age of the patient
—is placed a hollow^ crown, on the buccal surface of which is soldered
an open tube or trough, opening upward. On each bicuspid is soldered
a band with a buccal hook pointing downward, also on the first molar
if the second has been used for supporting the hollow crown. On the
incisors are cemented bands with hooks turned upward. A labial bow
of elastic German silver or piano Mire has its ends inserted in the
troughs of the hollow crowns, its front resting above the hooks on the
incisors and its sides pressed under the hooks on the bicuspids and
first molar. The action is such as to depress the incisors and elevate
the bicuspids and, if possible, the first molar also. The hollow crown
should be high enough to open the bite the required distance.
Class 15. Separation in the Median Line.—The simplest treatment
of this irregularity is to draAv the centrals together with a rubber band or
with twusted silk or linen ligatures passed two or three times around the
teeth. They can be retained by a wire band passing around both teeth.
In some cases it is better to cement on the lateral incisors bands
with tubes on the labial surfaces and draw them toward each other by
means of a long drag-screw, as shown in Fig. 814.

Fk;. 814.

Appliance for regulation and retention.
The same appliance serves for retention by adding cement to the
screw behind the nut to prevent its loosening. The advantage of this
plan is that the space is left next to the canines instead of between
the centrals and laterals, and also that the centrals will be more easily
retained in their new position if they are supported by the laterals. If
the central incisors are far apart and the roots are parallel, they will
slant too much when moved together as described. It is necessary
1 Dental Review, Feb. 15, 1896, p. 126. ^ Ibid., Dec. 1895, p. 867.