Preparing a Case to be Properly
Processed for Sunflex® Partials
Before starting, a cast model should be carefully studied.
The flexibility of Sunflex allows designs that use tissue undercuts as well as portions of the abutment teeth for retention. Deciding which clasp type to use would depend
on its position. With anterior position, esthetics is important, therefore, consider minimal coverage of the teeth.
With posterior position, clasps should provide utmost
support and stability of the partials.
Designing the Master Model
As always, make full use of tissue undercuts for retention.
It is recommended that red pencil is used during designing on the master model.
Preparing the Master Model for Duplication
Do not over-relieve nor over-block. The only time surveying may be required is to create parallelism for a clear path of insertion for interproximal saddles, removing mesial and distal undercuts. However, when left and right interproximal saddles are to be replaced, there won’t be any need to create parallelism because the degree of flexibility of the Sunflex material allows the partial to be twisted slightly during insertion.
All undercuts that will affect the path of insertion should be blocked out. However, undercuts, often on buccal and distal, should not be blocked out, as these will be utilized for retention.
It is important to remember that there is no need to relieve the necklines of the tissue except when there is indication
of some abnormal recession or some pocket formation.
If necklines are healthy, no relief with wax is necessary.
For free-end cases, upper or lower, it is not necessary to remove the distal undercut of the last natural tooth. For free-end saddle cases with anterior teeth replacements, undercuts in the front section should be blocked out with wax. Always leave distal undercuts for retention.
Placing wax relief on the gingivae is important for designs that use finger extensions. An anchor clasp will serve as retentive point for such a situation.
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Set-Up
Set-up is done on the Master Model.
The normal method of set-up is followed except when a tooth is to be replaced beside a tooth that will have a spur clasp. Here, one must allow a little more space at the neckline so that the resin material will have some reinforcement from the lingual to the spur.
Always set-up using all wax. Do not use acrylic base plates
or shellac base plates, as they create too much thickness.
Mechanical retention of denture teeth (acrylic type is preferred as this follows the principle of non-breakage) is achieved using retention burs to make diatoric holes.
Waxing
With Sunflex flexible partials cases, there is thinner wax-up compared to conventional acrylic partials. Thickness needed should just be enough to provide support especially at critical junctions and connectors. Sunflex flexible partials
are unbreakable with proper design and with proper processing. There should not be any bulky flanges.
Recommended thickness of the wax pattern:
- Palatal thickness: 1.25-1.5mm
- Buccal & Labial Flange: 1.25-2.0 mm
- Clasps: 1.0-1.5mm (Always uniform with flange
and junction)
- Lingual Flange: 1.25 –2.00 mm
- Lingual Major Connector (Mandibular) : 1.75 –2 mm
- Wax pattern should rest on the cingulum of anterior teeth.
- Wax pattern should include the lower 2/3 of
the 3 posterior teeth.
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