Faculty Of Oral & Dental Medicine,
K.S.U
Removable Prosthodontics
Dept.
Steps Of
processing of
complete Denture
prepared by :
Amr mohamed el.adle
soheir mohamed abd almunem

Introduction
what is the processing ?
It is the process by which the trail denture base is
converted to the permanent base that fit the patient's
mouth and compatible with the tissues.
Denture processing use two techniques :
1) Compression Molding.
2) injection Molding.
Compression Molding technique : ( the most commonly used
technique for acrylic resins ) Preparation of the trail denture.

steps:
 Flasking.
 Acrylic mixing.
 Acrylic pressing.
 Finishing.
 Polishing.

Flasking:
 Flasking is the process of investing the cast with the waxed denture in
a flask to make a sectional mold that is used to form the acrylic resin
denture base.
 What is flask?
 The flask is a metallic mold that supports the models and the try in denture
during the flasking procedure.
 It is composed of 3 parts:
1. Base
2. Mid-part
3. cover

Flasking steps:
 Separating media added to flask.
 Lower portion of flask is filled by dental plaster to fix the cast on it.
 Plaster shouldn't make any undercut. After preparing upper and lower portion of
flask,

 Seat the upper portion of flask, dental stone is added on all surface.
 Incisal and occlusal surfaces are minimally exposed to facilitate deflasking .
 Apply spreading medium only on stone.
 Add additional increment to fill the reminder of flask.
 Then cover the flask and remove excess stone.
 Put the flask in flask clamp.

 Dewaxing, put the flask in boiling water 100 °C for 5 minutes to remove wax.
 Open the flask and put it at boiling water again to remove residual wax.

Acrylic mixing and pressing:
 We use heat acrylic resin .
 Polymer to monomer ratio 3:1 by volume until dough-like st.
 Acrylic placed into mold cavity and covered with cellophane for trial packing to remove excess on
hydraulic bench press.
 compress the flask slowly in the hydraulic bench press so that the excess resin material flows out
 remove the flask from the clamp, open the flask and remove the sheet
 remove the excess flash with the blunt knife with out making a mark on the plaster surface
 apply another coat of separating media on the surface before the final closure of flask

 the flask kept in the bench press for 30 min before heat curing
This is called bench set or bench cure
*After the bench set, the flasks with the clamp are kept in the curing bath(water bath)
The curing cycle can be short cycle or long cycle.
I. Short cycle: The denture is placed on water at room temperature and the curing
temperature is programmed to 74 C for one and half hour followed by 100 C for one hour
under pressure.
II. Long cycle :The curing temperature is programmed to 70 C for 7 hours then 100 C for 3
hours ( the total 10 hours) .
*Polymerization can occur at any temperature but it very slow at temperature below 70 C
*The best curing cycle is the long curing cycle because most of the conversion of
monomer to polymer occur during the period at 70 C and the rapid cycle method may
include greater dimensional changes in the dentures than slow cure.

• *Mixture must pack in doughy stage with excess amount to make up for the
shrinkage during polymerization and refrigeration; it will be unworkable.
 Deflasking .
deflaking should be done with care to avoid flexing and breaking of the acrylic
denture.

Finishing:
 Each denture is hand finished using special burs to remove any excess acrylic around the
edges and palatal area. The articulation is checked and adjusted if necessary.

Polishing:
 Finally, the denture is polished and smoothed with polishing mops and paste. To
create a natural-looking luster.