Finishing

FINISHING of complete denture is the process of perfecting the final form of the denture by removing any flash, stone remaining around the teeth, and any nodules of acrylic resin on the surfaces of the denture base resulting from processing.
Flash It is the excess of acrylic resin at the denture border, the acrylic resin that was forced out between the two halves of the flask by the pressure applied during the processing procedure.

PROCEDURE OF FINISHING

Take care to preserve the border and contour of the denture during the finishing process. If the impression was correcting molded and boxed, and the trial denture was carefully waxed contoured into the form desired in the finished denture, little finishing will be necessary.
1- Carefully remove remaining stone around the neck of teeth with a small sharp knife.
2- To remove the flash of acrylic resin from the denture border, press the denture base lightly against a slowly revolving arbor band mounted on the dental lathe. An alternate but less satisfactory to use a large acrylic bur or stone bur mounted in a straight hand piece to remove the flash. Take care not to change the form of the denture border but only remove the excess resin on the border of denture.

3- Remove nodules of acrylic with small stone or acrylic carbide burs.
4- The posterior area of the palate has been thinned to its proper thickness.
POLISHING is a process of removing scratches. Polishing consists of making the dentures smooth and glossy without changing the contours.
PRINCIPLES OF POLISHING
1- The tissue surface of a denture is never polished as a polishing destroys the details necessary for good fit and retention.
2- The polished surface extends just over the border, but the borders are not reduced in height and width during polishing.
3- Care must be taken when using pumice (it should be used as wet slurry) as this material is very abrasive and may obliterate the details placed on the denture when they were waxes (festooned).
4- Resin teeth have approximately the same hardness as the denture base, so polishing a denture with resin teeth requires some precautions not necessary with porcelain teeth.
5- When polishing, only the denture base and not the teeth are polished.
6- During the finishing and polishing we should minimize the reduction of bulk because this cause warpage.

Procedure of polishing


1- Polish labial, buccal, lingual, and palatal external surfaces of the denture with wet pumice on rag wheel attached to dental lathe running at slow speed. Keep plenty of pumice on the denture surface and keep the denture moving at all times; press the denture lightly against the wheel.
2- Polish acrylic around the teeth with wet pumice and a brush wheel attached to dental lathe moving at slow speed. Be careful not remove previously developed contours.
3- Polish the border, lateral and palatal surfaces of denture by using wet muslin buffing wheel attached to dental lathe.
B- MAKING THE DENTURE GLOSSY:
1- Use Rouge (greasy material) this material is applied to dry muslin buffing wheel, this differ in that the polishing compound is applied to the wheel not as pumice to the piece of work being polished.
2- After the denture completely polished with rouge, it is scrubbed thoroughly.

3- Final polish is obtained by placing high shine material on the denture.
4- Store the polished dentures in water until they have been delivered to the patient. Store the dentures in water all the times otherwise they will undergo dimensional changes and shrinkage.

Every new set of complete dentures should be tested in mouth for tissue adaptation and retention and any pressure area should be indicated by using pressure indicating paste, and overextended borders should be indicated by using disclosing wax.