One method of testing for shade compatibility is to overlay a thin layer of the various composites being used in the process on the unprepared, unetched tooth and to light-cure it for a few seconds before beginning the procedure.
(Fig 6) Once the teeth were conditioned with phosphoric acid and a bonding agent, the initial layer (shade A2) of microhybrid resin was applied to the lingual aspect.
The maxillary teeth were micro-abraded with 50-um aluminum oxide and then etched with 37% phosphoric acid. This combination would maximize retention and stain resistance where the composite ended on the tooth surface. Since the restorations were placed entirely on the enamel, this provided an extremely strong bond. The phosphoric acid was applied for approximately 20 seconds. One, two or three teeth were etched at a time, depending on where in the process they were restored. The central incisors were done individually to develop the most ideal symmetry. Because we were working in a controlled field and moisture and blood contamination were not factors, the procedure moved along much more rapidly if two or three teeth were etched at a time. The etched surfaces were immediately covered with bonding resin and, since the air-inhibited layer was not disturbed, more resin could be added over the prepared surface. The appearance of the etched facial and lingual surfaced of the teeth was frosty when dried. Gluma Comfort Bond + Desensitizer (Heraeus Kulzer) was applied to each tooth, air-thinned, and light cured for 20 seconds with a halogen curing light.
With the putty guide in place and held from the lingual aspect, a layer of microhybrid composite (Venus Opaque A2) was applied to the incisal edge of tooth #8 and packed tightly against the guide on the lingual aspect using a flat, stiff sable brush. The incisal edge was left irregular to allow for light transmission that would create a natural incisal translucency (Fig 6). This first layer was cured with the guide in place for 40 seconds. Another layer of composite (Venus A1) was placed over the opaque layer, using the guide to shape the incisal third f the tooth. This layer was again light-cured for 20 seconds.
(Fig 7) A layer of A1 microhybrid composite was contoured to place. A lavender tint was then applied in the incisal third to accentuate the translucencies of the A1-shaded layer.
(Fig 9) Once the composite was cured, the general shape was finished with a tapered fine diamond without water irrigation.
(Fig 8) The facial surface was built up with microfill resin from the incisal to the gingival edge.
The guide was then removed, and a lavender tint was conservatively applied to the incisal third and cured in order to accentuate the translucencies of the A1-shaded composite (Fig 7). A final layer, the entire facial surface of the resoration, was placed using Durafill B1 microfill resin (Heraeus Kulzer) from the incisal edge to the gingiva (Fig 8). Once the composite was cured form both the facial and lingual aspect, the general shape was finished with a tapered fine diamond without water (Fig 9). This enabled better visualization of the surface texture - which would develop a chalky white appearance - while the composite was removed with the bur.
Dr Rhys Spoor DDS Aesthetic / Restorative Dentistry - Providing services in cosmetic and sleep dentistry to the area of Seattle, Washington.
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