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Flexibility is our Strength
Purpose Background and
Theory of Valplast Flexible Partials
Case Histories and Special Applications
Planning Successful Valplast Restorations
Why Valplast Flexible Partials?
In late 1940’s, people became more conscious of appearance.
Patients demanded more aesthetic dental restorations
Prevailing Dental Materials Metal and
Acrylic became standard but only for about 10 years.
Metal frame design became more scientific and standardized.
Limitations of Materials
Metal Frames display the clasps
The partial requires routine patient maintenance and modification to remain stable.
D ow nw ard Forc e
A s spac e opens under sadd le, roc king m otion d is torts c lasps and enhanc es hing ing effec t.
Where the Research Ends
Throughout the 1910’s, 20’s and 30’s, researchers acknowledged the damaging effects of rigid partials.
The research in removable prosthetics is replaced by research in new, more aesthetic, and more stable fixed prosthetic techniques.
New direction still leaves gap in economical and simple solutions.
Some Functional Issues
The Distal Extension partial is our greatest challenge, so we will focus on this
Free-End Design
The Distal Extension or Free-End Saddle restoration poses a greater challenge because it is partly supported by the tooth and partly by the residual ridge
The Forces
Fulcrum Line Axis
Longitudinal Axis
Lateral Force
The Goals of Partial Design
The goal of framework design is: Retain the Partial Support the partial
The challenge of Conventional RPD design is to balance the requirements of retention and support while minimizing damage to natural dentition and the supporting ridge.
One of our Better Options
Mesial Driving Force with RPI Clasp
Drawbacks
Requires precise guideplane prep
Very accurate surveying required
Modified or Altered Cast Impression recommended
Requires routine maintenance and reline
Fails easily with improper preparation
Where Valplast Comes In
Valplast came into development during this time
Improvements are intended to address process, functional and aesthetic limitations
Simple, safe and effective.
Thinking Beyond Design
The Valplast approach is to address the requirement of retention and support by leveraging flexible base properties with simple designs.
Advantages of Valplast
Aesthetics are obvious. The metal clasp is eliminated entirely
The natural translucency blends in with the gum tissue.
Functional Solution
Flexibility acts a stress-breaker to disengage forces on individual saddles.
• Balanced distribution of forces over the edentulous areas
• Elimination of unnecessary stresses on remaining natural teeth
Long Term Function Tissue Conditioning: The Flexibility of
the resin allows the partial to create a gentle stimulation of the gum improving circulation and tissue vitality.
Stress Relief: The Flexibility of the resin eliminates the fulcrum effects that produces a network of damaging stresses throughout a conventional rigid partial.
Wolff’s Law: Under normal physiological stress, bone mass stabilizes at normal levels. Under excessive stress, mass increases, and under low stress, bone resorbs.
Why no Vertical Stops?
The stop or rest is useful only in a rigid or semi-rigid frame as part of the support and balance structure.
The flexibility of the Valplast eliminates the need to balance stresses against tooth surfaces.
The flexible base is self-balancing.
Case Histories
All theories mean something only if they really work in practice. The following case histories illustrate a small sample of the practical results.
Case 1: 12 Year Partial
Photos provided byDr. J.F. Warriner, Oklahoma City
Patient received Valplast Maxillary partial in December, 1985.
Partial last adjusted in March, 1986.
Photos taken May, 1997.Note the healthy mucosa
over the tuberosities
Case 2: 7 Year Partial
Mandibular Valplast Partial inserted in 1990.
Note gingival healthand excellent color.
1989, Immediately prior to extraction
1997, After partial worn 7 years
Dense horizontal bone isapparent at same levelas before extraction
Case 3: 4 Year Partial
Partial inserted in 1992.
These flanges are very comfortable and esthetic
Note gingival health on labial and palatal sides of abutment tooth.
Typical Cases
Mandibular Partial Denture
Teeth #21-25are retained
Note the flangesare almost invisible
Excellentesthetics
Maxillary Partial Denture
Mandibular Partial Denture
Instead of a metal clasp, Valplastpartial dentures utilize a flexiblenylon extension.
Special Applications
Oral Carcinoma
These thin Valplast flanges are less bulky andmore comfortable than conventional acrylic.
Full Denture for Boney Tuberosity
The flexible flanges are excellent in cases
which have inoperable or large undercuts.
Aesthetic Correction
Flange provides gingival architecture,restores speech and improves mastication efficiency.
Special Needs Valplast Partials are ideal for people in high-risk situations
Athletes Police and Firefighters Military Personnel Prisoners and Prison Officers Any person who might be exposed
to harm or injury
Perfection?
Does Valplast solve all the problems of partialrestoration?
We believe that no product can solve all theproblems of partial restoration. The key is to solveas many as possible in a simple way that is affordable for the patient. We have focussed onimprovements over conventional partials inAesthetics, Function, Durability, and Longevity.
How Long Do They Last…(Really)? For real…as long as the mouth
undergoes slow, healthy, gradual change, the partial will remain functional.
Patient comfort is a good guide of function.
Only drastic or abnormal changes in the mouth require addition, rebase, or a new partial.
Valplast resin is created so that material failure does not become a factor in causing appliance failure
Indications
Valplast partials can be offered whenever a conventional partial is considered.
Additionally, Valplast can be used in most cases where metal and/or acrylic is not usable or preferable.
We have not encountered any limits to restoration with Valplast not solved by an experienced technician.
Indications
Numbers that Mean Something Valplast has a flexural modulus of
475 MPa at Body Temperature This is the appropriate degree of
flexibility for the partial to function in a predictable way WHEN DESIGNED AND FABRICATED CORRECTLY
Other flexible type resins have drastically different flexural properties and may not be usable in this application
Recap of Advantages
Aesthetics Confidence Durability Simplicity Reliable Lab Processes Clinically non-invasive Lab-Manufacturer Cooperation
Clinical ProceduresSubmission Guidelines Perfect Alginate Impression Bite Registration Try-In Insertion Adjustment Patient Care Instructions
Impression Technique
Alginate impression material minimizes compression of alveolar mucosa and muscle formations
Mucostatic Impression Required
Insertion Procedure
Partial must be immersed in hot water prior to insertion
Slight increase in flexibility minimizes the patient’s reaction to the first unfamiliar sensation
Adjustment Abrasives
Valplast partials are pink. But that’s all they have in common with acrylic. If grinding needs to take place, carbide burs and acrylic instruments should not be used. Instead, using a rapid, light shaving motion, use:
•Vulcanite Burs
•Green and Pink mounted stones
Stain Resistance
Valplast is Denser than Acrylic
Translucency will show surface deposits more easily
Polishing technique is critical to long term stain resistance.
Brown Tripoli must be used to smooth the surface properly.
Cleaning
We recommend the use of Val-Clean because it works better than anything available in drug stores.
Eventually, drug store cleaners will leave a film, and a dull, lifeless surface.
Consistent use of Val-Clean will preserve and even restore the intended appearance of the partial.
Repairs, Relines: Myth and Reality Teeth can be added either by
welding or injecting to Valplast partials
Valplast partials can be relined or rebased: both are laboratory procedures
Relines are less frequent with all-Valplast partials than with metal and acrylic or metal and Valplast combos.
Tooth Additions
Alginate impression with case in place
Remove any deposits, pastes, or lubricants before pouring model.
Counter model and bite Forward to laboratory for
processing Small welded additions can be
made at the clinical lab with simple equipment and proper training
Reline/Rebase
Rubber Base reline impression, closed mouth
Pick-up overall alginate impression
Pour model and forward to laboratory
Making Millions Smile