COMPLETE DENTURES



12. MAKING THE MASTER CAST
Boxing the Impression

The purpose of the boxing is to provide a proper size base without inverting the impression. The minimal height of the base is 1/2in (12.5mm). The thinnest points of the base are most likely at the lingual flange or the highest point on the palate. Always make the stone base a little thicker, and then cut it down. (It is a good idea to position the impression so that the ridge is parallel to the bench top. Then the eventual base will be parallel to the ridge crest.)

The boxing wax should never touch the impression. It should stand away at least 3mm, preferably 5mm. The beading wax should be wide enough to provide this space.

Of minor importance is the blocking out with wax of the area between the retromolar pads. You can fill this triangular space with stone and then grind it out later.

If you use rubber base you should pour up a model within an hour of making the impression. (If you can.)

Previous page Next page



©1999 by Julius Rosen, D.D.S.