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New Life for Existing Removables
Enhancing your artistry by rejuvenating dentures
By Jim Collis, CDT
When the option of replacing existing removable appliances with newly fabricated removables is not economically or otherwise feasible for the patient, the clinician can offer another valuable but far less costly alternative that can dramatically enhance the appearance of the existing full or partial dentures (Figure 1). Crafting “new life” for existing removables can be achieved by transforming the gingiva and/or tooth surfaces of the appliances using color composites (Ceramage, Shofu, shofu.com).
The first step in the restoration process is to rebase or reline the existing full or partial denture. The preference is to rebase the denture, replacing all of the original base acrylic, thereby eliminating bacteria that may have slowly permeated the original acrylic. The laboratory can use its own standard rebase or reline technique for this step (Figure 2).
After the denture has been rebased or relined but before it has been polished, the technician will sandblast or roughen lightly with an arbor band all gingival and/or tooth surfaces to which Ceramage color composites will be applied. Arbor bands are preferential to burs because they do not have the tendency to “grab” in the way burs do; also, arbor bands tend to yield a more uniformly roughened surface. Sandblasting is an equally effective means.
Next, a bonder (Ceraresin, Shofu) is applied to all surfaces—base or teeth—that will be accepting Ceramage. Ceraresin Bond is a 2-part bonding system that can be used to bond resin to composite and also composite and resin to ceramics. The first part of the bonder prepares and actually etches the surfaces to which it is applied. The second part is a light-cured bonder. With a small brush, Ceraresin Bond 1 is applied thinly and uniformly. This layer dries within approximately 10 seconds after application. Then a light but uniform coating of Ceraresin Bond 2 is painted on the same surfaces (Figure 3). The appliance is placed in a light unit for 3 minutes to cure the bonder.
In creating the newly enhanced surface of the full or partial denture, the next step is the application of the deep tissue color composite, Ceramage F-Gum-R (flowable red). A nickel-sized quantity of the flowable red is placed onto a mixing pallet and diluted with an equal quantity of clear liquid (Lite Art, Shofu) (Figure 4). The reason for the dilution is to achieve a “modeled” look with shade variation to allow some of the denture base shade to show through. If more contrast is desired, then use less Lite Art clear liquid.
The diluted flowable red is painted on the denture base surface, preferably with a dampened synthetic brush to hold the composite but release it from the brush once applied. The flowable red is applied one quadrant at a time, followed by a 10-second set in the curing-light unit. This will not completely cure the composite, but it will set it to prevent slumping. If desired, the flowable red also can be applied to the palate area, followed by a 10-second set in the curing-light unit (Figure 5 and Figure 6).
Once the flowable red has been applied, Ceramage F-W (flowable white) is applied only over the root eminences of the denture. The flowable white is administered in its undiluted state because it is being placed, not spread, over the root structures. Using a smaller, dampened brush to enhance the accuracy of the placement of the material, apply flowable white to 1- to 2-root eminences at a time starting at the sulcus and pulling it down to follow the contour of the root eminences. After each 1- to 2-root-eminence application, set the material for 10 seconds in the light-curing unit (Figure 7).
If the palate has been enhanced using the flowable red, the rugae can be drawn in flowable white using the fine brush and followed by a 10-second set in the curing-light unit between each line that is drawn. Not every patient or dentist desires rugae in the palate, so it is advisable to communicate in advance to know the clinician’s preferences.
The next step for enhancing the base is to apply a very small amount of F-Gum-V (flowable violet), again diluted by about 50% with Lite Art clear liquid. The diluted flowable violet is applied using the larger, dampened, synthetic brush around the buccal surface of the denture border. This application is done one quadrant at a time, followed by a 10-second set in the curing-light unit. A very thin, translucent layer is desired to provide the illusion of blood-engorged unattached gingivae.
If the teeth also have been sandblasted or arbor banded and coated with Cerarasin Bond 1 and 2, then Ceramage Tooth Color Composite can be applied to fix any broken teeth, fill chips, or enhance esthetics. Stains in the Lite Art kit also can be used on partial denture teeth to match the abutments. If it is desired to add additional translucency and vitality to the tooth surface, then a very small amount of flowable violet, diluted by at least 50% Lite Art Clear liquid, can be applied using a small, dampened, synthetic brush to the corners of the centrals, laterals, and the tip of the cuspids, followed by a 10-second set in the curing-light unit.
Before a final cure is performed, every surface where composite was applied (gingival and/or teeth) is coated with Ceramage Oxy-Barrier (Figure 8). The coated appliance is placed in the light unit for a 3-minute final cure (Figure 9). After the final cure, the appliance is placed in the ultrasonic cleaner to remove the Oxy-Barrier. Rinse and polish in the standard manner by pumicing and buffing to a high shine (Figure 10).
Ceramage composites are some of the finest composites on the market because they are uniquely composed of 73% zirconia, adding to their strength and yielding a beautiful, natural appearance in terms of color translucency. Ceramage Gum kits come with 4 shades of paste: Gum-L (light pink), Gum-Or (medium pink), Gum-D (dark pink), and Gum-T (translucent). Six shades of flowables are available: F-Gum-R (flowable red), F-W (flowable white), F-Gum-V (flowable violet), F-Gum-Br (flowable brown), Gum-O (flowable pink opaque), and WO (flowable white opaque). The flowable pink opaque can be used around implants or metal structures to be layered in tissue-colored composites. The flowable white opaque can be used on metal surfaces to mask the metal where tooth-colored composites will be applied. All these composites are from the same family and can be mixed with one another to customize color.
The Ceramage Gum Color Set, Ceramage Tooth Colors, and the Lite Art Set can give new and greatly enhanced life to existing dentures. The application technique is a simple series of steps and can yield incredibly beautiful results.
Jim Collis, CDT, owns Collis Prosthodontic Laboratory in Mount Prospect, Illinois.