Page 293 - My FlipBook

COMPOUND CAVITIES. 291

"Whenever the matrix is to be employed it must be understood that an
important feature is absolute fixation of the device, otherwise the ope-
rator will suffer continual annoyance throughout the operation.
Where there is sufficient space between the adjoining teeth for a
band matrix the operator \vill find great satisfaction in their use (they
Fig. 253.

Brophy's banil matrices.

are shown in Figs. 253, 254), but as most teeth are smaller at the neck
than at the occlusal surface, there is often difficulty in adjusting the

Fig. 254.

(^ 1^
III
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i
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Guilford's band matrices and clamps.
matrix to that portion of the tooth : a wedge used as previously described
will often overcome this difficulty.
A modification of the band matrix has been devised by Dr. Guilford,
and is shown in Figs. 254, 255. It will be seen that space upon both
sides of the tooth to be filled is unnecessary, as the little clamp binds the
matrix to the tooth. Another style of matrix, and one admirably
adapted to many cavities in the bicus]iids and molars, has been intro-
duced l)v Dr. AV. A. "Woodward, and is shown in Fig. 256. It will be
seen that this matrix has two screws which are driven against the