Porcelain-metal Philip

J. Render,

pontics D.M.D.,*

and

Dennis

for removable E. Jennings,

partial

dentures

D.D.S.**

Fort SamHouston,Tex., and Fort Bragg,NC. A custom-made denture may be use of this type superior esthetic PROSTHET DENT

porcelain-fused-to-metal ring pontic for a removable partial color characterized and glazed by use of familiar procedures. The of pontic on removable partial dentures has the potential of results when replacing isolated maxillary anterior teeth, (J 1991;65:452-3.)

w

hen missinganterior teeth are replaced with a removable partial denture,’ shade matching is often a problem. Manufacturers of denture teeth provide a limited selection of shades,2and often the best available choice may still be an obvious mismatch.A commonmethod used in fixed prosthodontics to achieve an ideal color match is the color characterization of porcelain-fused-to-metal restorations usingextrinsic stains.Porcelain denture teeth are glazed at much higher temperatures than fixed partial denture porcelain, and the limited selectionof baseshades of artificial teeth makes color correction difficult.3 In this procedure, the porcelain and metal of choice are usedto producea custompontic that canbe color-corrected with familiar techniques. A lingual ring provides a handle for porcelain fabrication and alsoservesasthe mechanism of attachment to the removablepartial denture framework.

PROCEDURE 1. Make a removable partial denture framework with special mesh for retention lingual to the tooth to be reTheopinionsandassertions hereinarethoseof theauthorsandare not to beconstruedasofficialor reflectingthe viewsof the Army or the Departmentof Defense. *Colonel,U.S. Army, DC; Director, ProsthodonticsResidency Program. **Major, U.S. Army, DC; ClinicalProsthodontist.

placed.The retentive meshshould have a deep(1.5 mm) external finishing line (Figs. 1 and 2). 2. Wax the pontic framework to full contour and cut it back to allow for an even thickness of porcelain. 3. Attach a wax ring to the lingual surface of the pontic, using the partial denture framework as a guide. 4. Sprue, invest, and cast the pontic in the metal of choice (Fig. 3). 5. When finishing the ring, grind it flat to a thickness of 1 mm. The trial fitting of the pontic framework to the removablepartial denture framework with clay isshown in Figs. 4 and 5. 6. Apply porcelain by using the procedure for porcelainfused-to-metal. The ring aids in supporting the pontic on the saggertrays during firing (Figs. 6 and 7). 7. Attach the pontic to the removable partial denture framework with beadingwax for the esthetic try-in (Fig. 8). When retained by the wax, the pontic can be removed and replacedreadily during recontouring. Color characterization can be accomplished at this time, either intraorally or extraorally. 8. After the pontic has been characterized, remove it and glaze it in a regular glazing oven. 9. Attach the completed pontic to the partial denture

10/l/18382

2. Meshwork seats in removable partial denture framework designedto receive pontic retentive rings (ar-

Fig. 1. Diagrammatic sketch of ring pontic and its meshwork seat in removable partial denture framework.

Fig.

452

rows). MARCH

1991

VOLUME

65

NUMBER

3

PORCELAIN-METAL

PONTICS

Fig. F:ig. held F:ig. F:ig. F:ig. Wig.

3. Ring pontic framework. 4. Pontic frameworks test-fitted in meshwork seats of partial denture framework in place with clay. 5. Facial view of pontic framework in place on master cast. 6. Completed pontic with retentive ring. 7. Ring acting as support on sagger tray for firing of porcelain. 8. Completed partial denture in mouth.

framework with autocuring resin after the denture base has been processed. The resulting partial denture can be made to look esthetically pleasing (Fig. 8).

Reprintrequests to:

REFERENCES 1. McCracken WL. Diff’erential diagnosis; fixed or removable tures. J Am Dent Aesoc 1961;63:767-75. TEE

JOURNAL

2. Sproull RC. Color matching in dentistry II; practical applications of the organization of color. J PROSTHET DENT 1973;29:556-9. 3. Preston JD, Bergen SF. Color science and dental art: a self teaching program. St Louis: CV Mosby Co, 1980;45.

OF PROSTHETIC

DENTISTRY

partial den-

DR. PHILIP J. RENDER 1005 GORGAS CIRCLE SAN ANTONIO, TX 78234

453