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CHAPTER VIII.
CONVENIENCE FORM.
Definition. Convenience form is that part of cavity preparation
wherein is made those additional changes necessary for the proper
placing of a filling.
Sparingly Used. As these additional cavity changes and their
accompanying loss of tooth substance are made entirely for the
convenience of the operator they should be resorted to only in cases
of necessity.
Maximum Convenience Form. The cutting necessary for con-
venience form reaches the maximum ; first, with inlay fillings, as
the previously prepared filling is moved to position en masse; sec-
ond, in the making of a cohesive gold filling, as it is of A'alue to
apply force as near as possible at a right angle to the anchorage
of the first portion of gold, and at an angle of 45 degrees to the
wall against which the gold is being condensed; third, in cavities
in the posterior teeth, and in distal cavities as compared with mesial
fourth, more is required for proximal fillings not previously sepa-
rated.
Minimum Convenience Form is required; first, in using plastic
fillings; second, in anterior oral locations; third, where the teeth
have had ample separation before the making of a proximal filling.
The Abuse of Convenience Form is of harm to the teeth and has
reached its height in a desire to inlay every case possible. When
excessive cutting for convenience form is necessary to the making
of an inlay, it would often be better to avoid the unnecessary loss
of tooth substance by changing the character of the filling.
Suitable Instruments for various locations in the mouth, par-
ticularly Avith the posterior distal cavities, will do much to minimize
convenience form.
Previous Separation is the most potent factor of all in lessening
the amount of cutting for convenience form, the same having been
considered fully in access form, and should be resorted to in cav-
ities of Classes Two and Three if for no other reason.
Starting Points for the making of a cohesive gold filling are a
jjart of convenience form and are made by making one of the
point angles more acute than is required for general retention.
This is made in the point angle farthest from the hand when the
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CHAPTER VIII.
CONVENIENCE FORM.
Definition. Convenience form is that part of cavity preparation
wherein is made those additional changes necessary for the proper
placing of a filling.
Sparingly Used. As these additional cavity changes and their
accompanying loss of tooth substance are made entirely for the
convenience of the operator they should be resorted to only in cases
of necessity.
Maximum Convenience Form. The cutting necessary for con-
venience form reaches the maximum ; first, with inlay fillings, as
the previously prepared filling is moved to position en masse; sec-
ond, in the making of a cohesive gold filling, as it is of A'alue to
apply force as near as possible at a right angle to the anchorage
of the first portion of gold, and at an angle of 45 degrees to the
wall against which the gold is being condensed; third, in cavities
in the posterior teeth, and in distal cavities as compared with mesial
fourth, more is required for proximal fillings not previously sepa-
rated.
Minimum Convenience Form is required; first, in using plastic
fillings; second, in anterior oral locations; third, where the teeth
have had ample separation before the making of a proximal filling.
The Abuse of Convenience Form is of harm to the teeth and has
reached its height in a desire to inlay every case possible. When
excessive cutting for convenience form is necessary to the making
of an inlay, it would often be better to avoid the unnecessary loss
of tooth substance by changing the character of the filling.
Suitable Instruments for various locations in the mouth, par-
ticularly Avith the posterior distal cavities, will do much to minimize
convenience form.
Previous Separation is the most potent factor of all in lessening
the amount of cutting for convenience form, the same having been
considered fully in access form, and should be resorted to in cav-
ities of Classes Two and Three if for no other reason.
Starting Points for the making of a cohesive gold filling are a
jjart of convenience form and are made by making one of the
point angles more acute than is required for general retention.
This is made in the point angle farthest from the hand when the
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