In-Office Porcelain Correction and Repair:
An Alternative Technology
by Ian E. Shuman, DDS

was decided to correct the occlusion and the open mesial contact chairside. This was accomplished chairside with the addition of a bonded restorative material to the mesial surface of the crown. The porcelain surface was first prepared by sandblasting with 50- micron aluminum oxide, rinsed, and then dried. Sand-blasting is a superior method in achieving macro mechanical surface preparation vs. roughening with a diamond bur. The sandblasting method provides a clean surface and increased surface area. This was followed by micro mechanical preparation of the porcelain surface using a 9.5% hydrofluoric acid gel. (Fig 2)

	2. Following mechanical etching with 50 micron aluminum oxide the porcelain surface is chemically etched with 9.5% hydrofluoric acid gel for four minutes (followed by ceramic primer and resin)
FIGURE 2

This method has been shown to greatly enhance bond strength when following sandblasting. This is rinsed, dried, and EZ Contact Primer, a silane is applied to the etched porcelain surface and allowed to air dry. Renew Resin-Bonding Agent, an unfilled BIS-GMA resin is applied to the treated porcelain surface and light cured for 20 seconds. EZ Contact Composite Resin is placed and sculpted to the desired contours and light cured. (Fig 3)

	3. EZ Contact porcelain replacement composite resin is applied and light cured.
FIGURE 3

This composite has unique optical properties that allow it to blend seamlessly with existing porcelain, creating a chameleon-like effect with the existing crown. The composite is then adjusted until an ideal interproximal contact has been achieved. (Fig 4)

	4. The resin-to-porcelain is properly contoured and adjusted allowing for a closed interproximal contact.
FIGURE 4

The crown is then cemented using an appropriate luting agent.

Case 2: Repair of Metal Island In this case, a 55-year-old male patient of record presented with recent porcelain fracture from a crown on his lower right second molar. (Fig 5)

	5. Loss of occlusal porcelain has created an island of metal in this lower right second molar.
FIGURE 5

In this case, it was determined that there was adequate occlusal clearance between the opposing teeth and because of the recent nature of this fractured porcelain, super-eruption of the opposing tooth had not yet occurred. This was likely due to traumatic occlusal forces that fractured the porcelain exposing the metal substructure. In such cases, there are three options available: replace the existing crown, repair the missing porcelain, or no treatment at all. Often, the replacement of the crown can be a source of discouragement to the patient who is usually comfortable with their existing restoration. Not treating this problem can create a complication since the thin metal coping is often insufficient to maintain proper occlusion or sustain heavy occlusal loads over long periods of time. The third option of repairing the crown intraorally allows a greater amount of flexibility in the treatment of these cases. In this case, the crown was isolated using a rubber dam. Using a diamond bur, the unsupported porcelain was feathered to the exposed metal providing a smooth transition from porcelain and metal to the new restorative composite.

Removing the unsupported ceramic and increasing the bulk of the restorative material can reduce the likelihood of further fracture. The exposed metal surface was mechanically cleaned and etched by sandblasting the surface with 50-micron aluminum oxide. (Fig 6)

	6. Using a rubber dam, the crown is isolated and the surface and blasted using 50 micron aluminum oxide powder. This cleans the bondable area and increases the surface area of the defect.
FIGURE 6

It is then rinsed, dried and chemically etched. In the past, tin-plating noble alloys was a popular method for creating an oxidized metal surface allowing resin adhesion to occur, however, this method is no longer required. By chemically etching the surface with Renew MetaEtch, a bondable oxide surface can be created. This is rinsed and dried followed by etching the porcelain surface with EZ Porcelain Etch Gel, which is then rinsed and dried. Silane followed by Renew Resin Bonding Agent is applied to the treated surfaces and light cured. At this point, the desired opaque shade is selected from the Renew Opaque System. This unique system provides a variety of opaque shades in powder form. The powder is mixed with Renew Bonding-Resin until a desired consistency is reached. The opaquer is applied in 1mm increments (Fig 7)

	7. An opaque composite layer (EZ Contact Renew Opaquer) is applied to the dark metal surface to enhance the esthetic outcome.
FIGURE 7

and light cured until the metal color is adequately blocked out. This is followed by layering a dentin shade composite followed by a microfill enamel shade composite layer (Virtuoso Composite, DenMat Corp., Santa Maria, CA). (Fig 8)

	8. Hybrid and microfill composites are used to build up the body portion of the crown (and light cured).
FIGURE 8