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Jlpproximal Cdvitics in Incisors and Cuspids.

It is essential that teeth be properly wedged before the preparation
of simple approximal and approximo-incisal cavities for inlays, to insure
proper withdrawal of matrices or impressions of the cavities, for the
insertion of the inlay, and that the inlay may have the proper contour.
The method of cavity preparation controls, in a measure, the extent of
space that is required. It will be found that those cavities in which no

Fig. 12. Fig. 13.

step is formed usually need more space than cavities with a step, for
the withdrawal of matrices or impressions from such cavities.
Simple approximal cavities in incisors and cuspids may be divided
into
(i) Cavities involving the approximal and labial surfaces (Fig.
13)-
(2) Cavities involving the approximal and lingual surfaces (Figs.
14 and 15).
(3) Cavities involving the approximal and both labial and lingual
surfaces (Figs. 17, 18 and 19).
In cavities involving the approximal and labial
surfaces the gingival wall should extend rootward
Gavities Tnvolving
Hpproximal and far enough to reach sound dentine. It should form
Cabial Surfaces. an obtuse angle with the lingual wall, and should
unite with the labial enamel wall in the form of a

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