Early advances in resin-based materials broadened their use to direct posterior restorations. Conventional composite resin restorations (designed to be placed in 2-mm increments) are subject to problems associated with polymerization contraction, which may generate microfiltration, air trapped between layers, cuspal deflection, and secondary caries. To address these problems, as well as optimize clinical efficiency, BISCO has created REVEAL HD Bulk, a high-viscosity material that is placed in increments up to 6 mm.
Bulk-fill composite materials are characterized as having a lower shrinkage stress and a higher depth of cure than conventional composites. Shrinkage stress is defined as the amount of force per area exerted on the walls of a cavity preparation by a composite as it polymerizes. Also, depth of cure is commonly measured by examining the hardness or the degree of double-bond conversion at the surface of a composite exposed to a curing light and comparing it with the degree of conversion at various depths of the restoration.
|Figure 1. Preoperative photo.||Figure 2. Excavation of carious lesions (tooth No. 18) and existing composite with recurrent decay (tooth No. 19).|
|Figure 3. Phosphoric acid etchant with BAC (total etch technique tooth No. 18, selective etch technique tooth No. 19).||Figure 4. Application of ALL-BOND UNIVERSAL.|
|Figure 5. Placement of REVEAL HD Bulk in 5-mm increments.||Figure 6. Occlusal adjustments.|
|Figure 7. Immediate postoperative photo.|
When a composite is light cured from the occlusal direction, light energy from the curing light must be transmitted through the bulk of the composite without being absorbed or deflected before reaching the bottom of the restoration. By adjusting the translucency of the composite or matching the refractive index of the filler and the resin, light can travel through an increased depth of a bulk-filled composite.
A 33-year-old white female presented with a history of old composite restorations and generalized decay in the posterior teeth. Upon examination, a caries lesion (tooth No. 18) and an old Class I composite restoration (tooth No. 19) were found (Figure 1). Removal of the temporary restoration and excavation of the remaining carious dentin and previous restorative material were quick (Figure 2). The preparations were etched with UNI-ETCH with BAC (Figure 3).
Two layers of ALL-BOND UNIVERSAL were applied, evaporating the solvent between layers and then curing with a polywave (VALO [Ultradent Products]) (Figure 4). REVEAL HD Bulk was placed in one 5-mm increment and light-cured (Figure 5). REVEAL HD Bulk is easy to condense and shape (Figure 6). Finishing and polishing are steps of paramount importance in any restorative procedure to ensure the longevity of the restorations (Figure 7).
In this particular case, placing REVEAL HD Bulk in a 5-mm increment reduced clinical time significantly and achieved the ideal adaptation to the cavity walls due to the fluidity of the material. REVEAL HD Bulk allows you to shape the occlusal anatomy and offers the desired aesthetics for the final restoration.
For more information, call BISCO Dental Products at (800) 247-3368 or visit bisco.com.