ASAD JABBAR ROLL #

Group D

It is a second (new) denture intended to be a

copy of the first (old) denture

OTHER TERMS USED ARE: Copy Denture Duplicate Denture Template Denture

Denture copy technique should be aimed at incorporating all the good & desirable features

of the old dentures in the new ones

The term replica denture implies the construction of a denture identical to the original which is exactly not the case

Generally using the copy technique , it is common to build in alterations of some features while keeping others the same

Need of replacement denture (in patients with successful immediate denture)

When improving some aspects of an old denture while keeping others the same

Copy dentures are made for use as emergency replacements in case the originals are lost

Elderly patients demanding spare dentures of same quality

Valuable during laboratory repair, reline or rebasing procedures of the original dentures; this offers the patients an alternative to being without a denture during laboratory relining of an existing denture

Where patient has poor neuromuscular control (e.g. palsy, stroke pts). In such cases any significant change in dentures polished &/or occlusal surfaces may not be tolerated

Also as a template to be used as record rims and special trays

The initial familiarity of the shape of the replica to the patient is an advantage since the patient is more likely to feel at ease and behave normally during the stages of impression and jaw relationship recording

Training dentures are given to patients who have presented with the adaptability problems

In this patients adaptive capacity is improved by slow and sequential additions of denture parts

Initially only plate is given then anterior teeth and finally posterior teeth are added to the plate

Denture copy technique helps to convert existing training appliance into more permanent prosthesis without discontinuing the patient from wearing the training appliance

A number of methods have been reported for producing a template for duplication of a denture

Commonly used are: Modified denture flask method Soap container method Others may be: Duplicating flask method Pour resin flask method Cup flask method Agar container method

Take a modified denture processing flask or soap box or two large equal sized impression trays

Clean & dry the dentures to be copied

Polished Surface

Fitting Surface

Mix a low viscosity alginate & place it in bottom part of flask or soap box or large impression tray

Denture is embedded into the alginate & small amount of alginate is allowed to spread over the polished surface

After setting excessive alginate is trimmed with sharp knife (if flask used, upto the flask flange level), 3-4 mm away from gingival margin of artificial teeth

Cut small notches(key ways) in the plateau surrounding the denture.

Apply a separating medium

The heels & posterior part of maxillary denture should be attached to green stick, two on each denture in order to form sprue formers (require in soap box tecnique)

Flask is assembled or soap box is closed & the second mix of alginate is poured over the occlusal surface (if flask used the lid is then closed with some adhesive).

In case of modified flask alginate is carefully placed into the fitting surface of the upper denture.

The other half of the copy denture flask is then filled with alginate as before.

The two halves are then closed and pressed together

Once set, the excess alginate is cut away

After setting of alginate disassemble the flask, remove the dentures and return them to the patient

Remove the sprue former to create pathway to pour acrylic or wax

In case of modified flask escape holes are then cut into the alginate 'teeth side' of the copy denture by using a serrated piece of tubing or similar on both sides as shown.

The template can be made with monochrome selfcure acrylic alone or by pouring wax in teeth mould portion & selfcure in baseplate portion. For the latter cold cure plate is first made onto the fitting surface

With the base plate in position in the flask, the two halves are held together using an elastic band for the next process .

The wax is then gradually poured into one on the escape holes until the wax appears from the other escape hole and the flask is filled with wax.

The templates act as impression trays & occlusal rims if the required adjustments are not done prior to the duplicating technique