Indirect Ceramic System for Posterior Esthetics

JOURNAL OF ESTHETIC DENTISTRY

Indirect Ceramic System for Posterior Esthetics LUCA L. DALLOCA, CDT. DMD. ROBERTO BRAMBILLA, CDTt

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igher esthetic demand by the public has led clinicians to request dental materials that could help the average practitioner routinely achieve satisfactory esthetics with the least amount of tooth reduction. In the past, many companies have developed new materials with this goal, from composites to castable ceramics. Esthetic restorative technique for posterior restorations can be divided into three categories: (1)the direct techniques that can be made in a single appointment and are an intraoral procedure utilizing composites; (2) the semidirect techniques that require both an innaoral and an extraoral procedure and are luted chairside utilizing composites; and (3) the indirect techniques that require several appointments and the expertise of a dental technician working with either composites or ceramics.

Figure 1. A 23-year-old patient presented with interproximal curies on teeth 25 and 26.

The direa technique is suggested for small Class I and medium-sized Class II cavities using filling techniques ranging from bulk-fill to more complicated multilayering incremental methods. Lager cavities in one or two teeth are best restored with semidirect techniques.

For full arch or serial restorations indirect techniques are preferred.'

One of the products that has yielded excellent results for esthetic indirect restorations is Empress (Ivoclar, Shaan, Liechtenstein). Empress can be used for esthetic onlays, inlays, crowns, and esthetic corrections (diastema, crown contouring, etc.) with the least amount of tooth reduction and, in some cases, none at all. The primary limitation of conventional crown materials is the

'Oral Design Centre, Arcore, Milom Ibly tPriuate practice, Arcore, Mikm. It& VOLUME 9, NUMBER J

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Indirect Ceramic System for Posterior Esthetics

Figure 2. Removal of caries and preparations for Empress restorations.

amount of tooth reduction necessary to produce esthetic crowns, usually from 1.5 to 2.0 mm. This amount of reduction is required for a metal substructure of 0.3 to 0.5 mm plus a porcelain thickness of 1.0 to 1.5 mm. The metal substructure limits the esthetic potential, because it does not allow light to penetrate and it is highly reflective.

The fabrication process is simple and requires only a wa-Up of the pattern, using significantly fewer steps than for conventionally fabricated porcelain restorations! Another advantage of the material is that it has a wear coefficients& lar to that of enamel,s which causes less wear of the opposing tooth. Empress crowns can be made either by stratification of a veneering porcelain or by superficial coloring, which improves the strength of the restoration.6 Indications for Empress restorations in the posterior region are for patients without parafunctions. The purpose of this article is to demonstrate clinical steps to restore posterior teeth.

Empress is an all-ceramic system that permits light to be reflected, scattered, and absorbed throughout the restoration and the underlying tooth structure. A major advantage of Empress over other types of ceramic materials is a translucency similar to that of enamel, providing a “chameleon effect” that allows it to blend with the natural tooth with a thinner application of Figure 3. Polyether impression.

DALLOCA A N D B I A M B I L L A

Figure 4. A, Immediate provkionals: B, with proper contour and margmal fi, C, luted with temporary cmunt, and D, with temporary inlays in place.

CASE REPORT

The patient, who had no previous restorations, presented for a routine dental examination (Figure 1). Bitewing radiographs were taken, and interproximal decay was observed on the mesial and distal surfaces of tooth 25 and on the mesial surface

of26. Esthetic restorations were suggested rather than conventional amalgam fillings. Subsequently, inlay preparations were performed (Figure2). Crown and inlay preparations for Empress should be smooth and without sharp angles. The final impressions of prepara-

tions were taken with polyctheq using a custom nay (Figure 3), and immediate provisionals were made and temporarily cemented (Figure 4). Shade was selected, and the impressions were delivered to the laboratory.

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J O U R N A L Of ESTHETIC D E N T I S T R Y

Indirect Ceramic Svstem for Posterior Esthetics

Figure 5. Various cement color options.

Figure 6. A, Teetb 25 and 26 ready for inlays cementation. B, Final restorations cemented. C, Final restorations on teeth 25 and 26 at time of cementation.

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During the subsequent appointment, the inlays were tried for proper fit and for proper occlusal and interproximal contacts. Esthetic try-ins utilizing various shades of composite cements without catalyst were performed (Figure 5 ) .A rubber dam was placed, dentin and enamel etched with 32% phosphoric acid, primer and unfilled resin applied, and each inlay cemented individually to inhibit microleakage and to obtain the best esthetic result (Figure 6 ) . Figure 7 shows another restoration at 1 year.

DALLOCA A N D BILAMBILLA

Figure 7. Occlusal inlay 1 year after mentation.

ACKNOWLEDGMENT

Special thanks to Roberto Iafrate, Marco Panzeri, and Andrea Bordogna for their help in the fabrication of the restorations.

REFERENCES

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I* 01997 Decker Periodicuk

4. intl?rLwaeluein cmmicu. QvintcxKlo

1991; 659:53-43.

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