How to create an esthetic posterior restoration [VIDEO]

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In this case, we present a video how-to of Dr. Michael J. Koczarski demonstrating how he uses Ivoclar Vivadent's Tetric EvoCeram nanohybrid composite to make posterior restorations efficient, easy and esthetic.

While there are many direct composites to choose from, each comes with its own limitations. Macro-composites, first introduced in the 1960s for use on anterior teeth, feature minimal shrinkage and favorable mechanical properties. The large particle size allows the incorporation of a large number of particles without rendering the material too stiff for dentists to manipulate. However, macro-composites are not suitable for posterior teeth because of their lack of wear resistance.1

Developed in the 1970s, micro-filled composites remain popular because of their superior esthetic qualities.2 Although they look great, the high percentage of small particles coupled with the low density of glass particles results in material stiffness, making it difficult for dentists to handle. Mostly used to veneer over restorations for their polishability, the low density fill renders them unsuitable for posterior restorations.

Today, however, nanohybrid composites like Ivoclar Vivadent’s Tetric EvoCeram are popular among dentists based on their excellent esthetics, high polishability, and superior wear and handling characteristics.3 Featuring an ideal consistency and eliminating the disadvantage of premature curing, Tetric EvoCeram allows for efficient placement using either state-of-the-art, ergonomic syringes or Cavifils, and provides extended working time for customized shaping.4

An innovative and patented additive was introduced to the composite’s photoinitiator system, increasing its resistance to ambient operatory lighting. However, when exposed to curing lights in the range of 400 to 500 nm, polymerization time decreases, ensuring a complete depth of cure. Research regarding polymerization shrinkage stress indicates that Tetric EvoCeram has one of the lowest shrinkage values, resulting in better marginal quality.5

Its excellent radiopacity makes Tetric EvoCeram clearly visible on radiographs and is easily distinguishable from changes in the natural tooth structure and dental hard tissues, enabling easier diagnosis of secondary caries or other complications. Available in three translucencies, Tetric EvoCeram features fillers, monomers and pigments of the same refractive index to enable harmonious blending with natural dentition. As a nanohybrid composite with filler particles smaller than 550 nm, Tetric EvoCeram demonstrates a high level of gloss and can be polished in 30 seconds. Because of its superior esthetics and excellent wear resistance, Tetric EvoCeram composite is indicated for anterior and posterior restorations and is available in a wide selection of shades.

Case presentation
A patient presented with a poorly contoured restoration on tooth No. 12, causing a food trap between tooth Nos. 12 and 13. In addition, mesial and distal caries on tooth No. 13 were identified radiographically (Fig. 1). After the initial examination and consultation, the patient agreed to treatment using Tetric EvoCeram.

Preparation of the affected teeth was initiated and interproximal decay exposed (Fig. 2). Interproximal decay often requires removing a significant amount of healthy tooth.6 The preparation was completed, decay removed, and recontouring of the restoration on tooth No. 12 created a fluid distal contour (Fig. 3).

Proximal contacts were obtained with interproximal banding; the 3D sectional matrix, Composi-Tight® from Garrison Dental (garrisondental.com), was the system of choice for the mesial to create a tight and anatomically correct contact with tooth No. 12 (Fig. 4).

The tooth was etched with Total Etch from Ivoclar Vivadent for 15 seconds on the enamel and 10 seconds on the dentin, rinsed and dried. Then, ExciTE F total-etch bonding system was applied by gently working it into the enamel and dentin for 20 seconds (Fig. 5). The adhesive was light cured for 10 seconds.

Tetric EvoFlow flowable composite in shade Bleach Incisal was syringed into the interproximal box area, specifically covering the proximal cavosurface margins and gingival floor. This shade was selected to mimic the final and visible enamel surface shade (Fig. 6). This layer was cured for 20 seconds.

The A3 shade body composite was applied, contoured with a P1 instrument, then cured for 20 seconds. The darker dentin shade was selected to match the natural dentin, and the tooth was built up with an anatomical shade application; the top enamel layer of Bleach Incisal was chosen to match the natural enamel shade. The top enamel layer also was cured for 20 seconds. By layering the enamel Bleach Incisal shade on top of the dentin A3, a final restoration in shade A2 was created (Fig. 7).

Pits and fissures were created at the ideal depth in the dentin layer, and cavosurface margins were created ½ mm short of the final depth to allow for varied thicknesses of the top enamel layer. The darker dentin noticeable at the pits and fissures, in addition to the blending of composite at the occlusal and interproximal cavosurface margins, created a chameleon effect (Fig. 8).

The final layer of composite was applied with the P1 instrument in the same Bleach Incisal shade as the initial layer of flowable composite (Figs. 9 and 10), then cured for 20 seconds.

The 3D sectional matrix was removed, and the final contours proved to be accurate (Fig. 11).

Finally, the margins were shaped and finished with a 40-micron diamond (Figs. 12 through 14).

The patient was seen one week later and the tooth rehydrated. The chameleon effect resulting from the Bleach Incisal shade and excellent proximal contacts with accurate contours produced a reliable and esthetic restoration that mimicked and blended seamlessly with the patient’s natural dentition (Fig. 15).

Closing thought
Indicated for anterior and posterior restorations because of its superior esthetic and wear characteristics, Tetric EvoCeram demonstrates excellent adaptability and extended handling time compared to conventional composites.3 The many advantages offered with Tetric EvoCeram include ideal material properties; easy placement and contouring; decreased curing time and polymerization shrinkage; excellent radiopacity, translucency and polishability; and a broad range of available shades that makes it the ideal composite for simple and efficiently performed, reliable, esthetic and durable restorations.