Page 26 - My FlipBook

While porcelain may be used as a material for filling many cavities in
bicuspids and molars with a fair degree of success,- it has nevertheless
been demonstrated that it is not the safest material to use for filling most
of the cavities in these teeth. It should be chosen, therefore, only where
the requirements demand it for filling cavities in bicuspids and molars.
The dentist who limits his practice to filling cavities in incisors and
cuspids with porcelain will probably render his patients better service
than the one who promiscuously inserts inlays in all classes of cavities
regardless of their indications and contra-indications.
Generally speaking, as the size of the cavities in vital incisors and
cuspids increases does the indication for porcelain inlays also increase, for
if a small gold filling at the gingival margin of an incisor or a cuspid is
conspicuous, such a filling in an approximo-incisal cavity is much more
noticeable. While there is a limit to the size of a porcelain inlay that
may be inserted in an approximo-incisal cavity successfully, there are,
nevertheless, too many crowns adjusted upon incisors and cuspids. The
comparative ease with which a crown may be adjusted upon these teeth
induces many operators to overlook the good qualities of porcelain as a
filling material for many large cavities. On the other hand, the decision as
to whether an inlay shall be inserted into a particular cavity should be
dependent upon the degree of the operator's skill. The prudent operator
will not attempt to insert large approximo-incisal inlays, for example,
until he has become thoroughly familiar with the methods of cavity
preparation and is a master, in a very large degree, of the technique of
inlav construction : for the construction of porcelain inlays involves a
series of mechanical principles, which must be observed with precision.
Failure to apply these principles will cause imperfect fillings. The best
work can be accomplished only when the operator possesses a through
knowledge of the principles of inlay construction, of the properties of
porcelain, a masterv of inlay technique, and when the eye is trained to
detect the delicate hues of colors.

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