Page 837 - My FlipBook

THE COSTOUBISG APPABATUS. 835

possesses certain qualities which render it adapted for the purpose to
which it is applied.
In making the banding material for this apparatus, thoroughly an-
neal a piece of wire No. 13 and pass it through the rollers—with an
occasional re-annealing—until it is reduced in thickness to Nos. 35 and
38 (or 0.004 and 0.0056 of an inch).i This will give bands about i and
of an inch wide. Use the thinner material for the anterior teeth
Y^^
and the thicker for the anchorage appliance. Before using, it should be
wound into rolls and brought to an even red heat, held there for ten
minutes, then allowed to cool slowly. This will ensure perfect softness
and adaptability.
In taking the measurements for the bands, cut from the material
the proper length, and, holding the ends of the loop between thumb and
finger, pass it over the tooth to be fitted. When in place bend the ends
sharply at right angles and finally, grasping the two ends in the pliers,
draw the band firmly around the tooth. The bands for the anterior
teeth should extend at this time sufficiently beneath the approximal bor-
ders of the gum to assure complete extension to the labio- and linguo-
gingival borders. The approximal extension should be cut down to the
gingival border of the enamel in the final finishing of the apparatus.
After the bands are soldered carefully, fit and burnish them to the
teeth. In order to obtain perfect adaptation it often becomes necessary
to contour them slightly with the proper pliers. The joint which pro-
jects on the anterior surface of the bands for the anterior teeth should
be placed at one side of the middle to allow the upright bar c. Fig. 893,
to rest exactly along the median line.
When the teeth are so crowded together that the banding material
cannot be passed freely between them they should first be separated
with waxed tape. It is to be preferred to rubber because sufficient
space is obtained in twenty-four hours with little or no discomfort to
the patient beyond the general soreness of the teeth, Avhich must always
follow the preliminary steps of a regulating operation. These tapes
are allowed to remain between the teeth—renewing them each day—till
the final attachment of the apparatus.
The first appliance to be described is that designed for moving the
roots of the upper incisors forward.
Before it is possible to apply the contouring force it is frequently
necessary to first move the crowns of very irregular teeth into aligu-
ment somewhat—and even to rotate them—so as to bring them into a
position to be properly grasped by the power bar of the apparatus.
(See Fig. 872, with description.)
^ In tliis description it will be nnderstood that German silver is the metal indicated
and Brown & Sharp's gange that by which thicknesses are measured.