Deflasking the dentures
Never pound on the flask with a metal hammer
Sould be accomplish with considerable care
Shaping and Polishing The Cured Resin Bases
The dentures are removed from the artificial stone casts
The feather edges of the denture base material are removed with files, scrapers and burs
The feather edges around the gingival line of the teeth are cut down by means of burs and chisels to conform with the desired contour
Any difficulty encountered in polishing the dentures is caused by the fact that they are not properly prepared for polishing
With burs, stones, chisels and sharp scrapers, the surface is shaped until it presents a smooth, clean surface
No plaster and no deep scratches should remain after the preparation for polishing
It is impossible to retain the desired contour of the dentures if abrasives such as pumice are used for all the finishing
A rag wheel and felt cone with pumice are used to finish the palatal portion of the upper denture
A single-row brush wheel and a rag wheel about 6 mm in widht are used with pumice to smooth the labial and buccal surfaces of the denture without destroying the contour
A final high polish is given all the surfaces with a rag wheel and polishing material (tripoli, tin oxide and water, or Shure Shine)
Attention
Resin teeth must be covered or protected during pumice and rag wheel smoothing: otherwise they appear too yellow because of the loss of the outer labial enamel shade from the denture inadvertent reduction while smoothing the facial side of the denture
The incisals can easily become knife-edged quicly while polishing the palatal surface
Gingival crevices should be polished with a brush wheel and an abundance of wet pumice.
Felt cones and dry rag wheels generate lots of heat, the former sometimes burning the resin surface of the reflections of the final cast and latter warping the base
