How to complete bulk fill restorations

Experience has shown that to achieve successful resin composite posterior restorations, composite layering is essential. However, proven to be time consuming and technique sensitive, the procedure must be performed properly to avoid polymerization shrinkage and marginal leakage.

Because dental professionals have continuously sought more advanced materials and more efficient techniques, dental research has led to the introduction of bulk fill resin composite materials.

Posterior restorations performed with bulk fill resin composite have been shown to be faster, easier and more predictable to place. Designed to eliminate many of the disadvantages associated with conventional resin composites, bulk fill materials display innovative characteristics such as a smoother texture resulting in increased flowability for complete and consistent adaptation to restorative preparations.

Enhanced depth of cure of up to 4 mm eliminates the need for layering, and increased elasticity and low polymerization shrinkage stress reduce postoperative sensitivity and microleakage that could result in secondary caries. With the development of bulk fill composite and new advancements in resin and photo-polymerization technology, dentists can be productive without compromising quality.

About the material
Ivoclar Vivadent’s Tetric EvoCeram® Bulk Fill composite provides a quick and easy solution to resin composite posterior restorations. Prior to the development of bulk fill composite, layering posterior restorations was tedious and consumed valuable chair time. With Tetric EvoCeram Bulk Fill, filling a Class II restoration takes less than half the time compared to conventional materials.

The incorporation of layered silicates provides a smooth consistency for increased adaptability to cavity walls and easy contouring with conventional dental instruments, as well as a reduced need for flowable composite. Featuring an innovative initiator system that boosts polymerization, 4 mm thick increments can be completely cured in a single 10-second interval, eliminating the need for layering.

With the introduction of a shrinkage stress reliever, the shrinkage stress distributed along cavity walls and surfaces, and volumetric shrinkage experienced during polymerization, are exceptionally low. In addition, polishing is easy and fast thanks to a well-balanced filler composition. Three shades, IVA (for slightly reddish teeth), IVB (for slightly yellowish teeth), and IVW (white for quick deciduous tooth fillings and for light-colored dentition) and an enamel-like translucency of 15%, allows seamless blending with the natural dentition.

Clinical protocol
A 50-year-old man presented with a chipped second molar in the right mandibular arch. Decay on the occlusal and mesiolingual surfaces extended into the proximal areas of the tooth, and caries exposure revealed dentin involvement (Fig. 1).

Rubber dam was placed to ensure proper and complete isolation (Fig. 2). Caries were exposed to reveal dentin involvement (Fig. 3).

Caries detection solution was placed (Fig. 4), caries excavation was completed, and the tooth was cleansed with a 2% chlorhexidine scrub for 30 seconds in preparation for a Class II restoration (Fig. 5).

A DENTSPLY Caulk Palodent matrix wedge and Bi-tine Ring was placed followed by enamel and dentin etching. The enamel and dentin were etched for 20 seconds and 15 seconds, respectively, with 37% phosphoric acid and then vigorously rinsed for 10 to 15 seconds (Fig. 6). The preparation was lightly dried, leaving the dentin slightly moist.

A single coat of ExciTE F 5th generation adhesive was scrubbed onto the tooth for 10 seconds, and air-dried for 2 to 3 seconds. The adhesive was then light cured according to the manufacturer’s instructions (Fig. 7).

Tetric EvoCeram Bulk Fill can be used with or without flowable composite (sandwich technique). In this case, gingival seat of the proximal box and pulpal floor were restored using Tetric EvoFlow composite resin placed into the pulpal floor (Fig. 8). Contact was established by placing an instrument into the box and pushing against the opposite contact area (Fig. 9). Tetric EvoCeram Bulk Fill can be used with or without a flowable composite. In this case, it was used to decrease tension along the walls that may have resulted from the “C” factor. Additionally, the flowable composite used readily reached and adapted to small irregularities in tooth structure, providing a great overall seal.

The composite was then light cured with a Bluephase 20i curing light for 5 seconds. The remaining cavity was restored with a single increment of shade A Tetric EvoCeram Bulk Fill composite.

The composite was sculpted using an OptraSculpt instrument and followed by curing for 10 seconds using a Bluephase G2 LED curing light for 10 seconds (Fig. 10).

The matrix band and wedge were removed and occlusion adjusted using finishing burs (Fig. 11).

Tetric Color was used to highlight tooth characteristics of a molar (Fig. 12).

The restoration was finished using 3M ESPE SofLex discs and polished using Optrapol one-step, high-gloss polishing system, flossed and revealed (Figs. 13-16).

Conclusion
Tetric EvoCeram Bulk Fill composite provides the perfect combination of productivity, performance and esthetics while reducing the posterior restoration completion time. It also helps simplify the technique for posterior restorations. Placing one bulk fill increment allows better artistic and anatomic sculpting of the composite in a manner much easier and less time consuming than layering. It also reduces the time spent finishing.

Reduced chair time results in decreased cost and discomfort for patients and increased productivity for dentists. The development of Tetric EvoCeram Bulk Fill replaced a labor-intensive procedure vulnerable to failure, with a quick, easy to accomplish and dependable restorative technique for posterior restorations.