Page 110 - My FlipBook

78 INSTRUMENTS AND APPLIANCES

operations on the lower teeth. Of these the Downie and
Kerr are the most prominent makes.
(c) Separator.—A steel instrument, designed for forcing

apart (wedge separator) or drawing apart (traction separator)
two approximating teeth, thus gaining space for making
examination of, or operating in, inter-proximal spaces. The
wedge separator acts on the principle of a wedge, by the forcing
together of two steel points; the traction separator acts in the
opposite manner by the drawing apart of two pairs of points;

while some instruments combine both principles. . The Ivory

Fig. 104.—Perry separators. Fig. 105.—Elliot separator.

(Figs. 102 and 103), ^^ Perry^' (Fig. 104), '^Little Giant'' and
Elliot (Fig. 105) separators are prominent examples.

Separation of the teeth is also accomplished through the
expansive properties of such materials as wood, cotton,
linen tape and gutta-percha (slow or previous separation).
(d) Matrix.—A thin band or strip of steel, German silver
or copper about o.ooi inch in thickness, used to restore the
fourth or missing wall in filling proximo-occlusal cavities,

thus converting them into simple cavities. The simplest
form of matrix is a thin strip of metal held in position by means