November/December 2005, Volume 1, Issue 2
Published by AEGIS Communications
Using an Improved Liquid Polisher for Enhanced Esthetics
Gary M. Radz, DDS
Many dentists and manufacturers have devoted significant time and energy to developing the optimal polishing sequence that ultimately leads to the creation of the most esthetic final restorative result. Abrasive discs, rubber or diamond polishing wheels, aluminum oxide, or diamond polishing pastes have all been incorporated into a variety of techniques to obtain the ideal final polish.
A few years ago, a liquid polishing product (BisCover,™ Bisco, Inc, Schaumburg, IL) was introduced that could be used to minimize the number of polishing steps, yet still provide an excellent esthetic result.1 Since its introduction, it is this author’s opinion that it has served as an excellent adjunctive material to assist dentists who are looking to impbody a high polish and natural appearance to their restorations. Additionally, the liquid polish has demonstrated the ability to improve the surface smoothness of composite resins.2
Recently, an improved version of this product was introduced: BisCover™ LV (low viscosity). This new version maintains the desirable clinical properties of the original material while demonstrating improvements in some important areas.
Characteristics of a Low-Viscosity Liquid Polish
The new, low-viscosity material exhibits a film thickness (i.e., 5 to 10 microns) that is one-half that of the original formulation. This is clinically noticeable; when applying the polish to the restoration, this author has noted that the liquid is thinner and appears to evaporate more quickly.
Despite the material’s low viscosity, its wear characteristics are slightly better (i.e., 1.7 microns/year in the original formulation compared to 0.4 microns/year in the new formulation), according to the manufacturer. This wear data was obtained by the manufacturer using a brushing experiment with an Abrasion Testing Machine (Pepsodent Co., Chicago, IL). A composite disk was coated with BisCover LV, immersed in a 20:80 toothpaste/water slurry, and brushed back and forth with a flat-bottomed toothbrush for 40,000 strokes (e.g., estimated number of brushings in a year). The amount of material removed (i.e., microns/year) was calculated by dividing the mass difference before and after brushing by the density of BisCover LV and the brushed area. Additionally, the manufacturer claims that the Barcol hardness of the new formulation is slightly improved, from 40 to 55.
BisCover LV now incorporates a solvent into the formulation that eliminates the need for a viscosity modifier. The cure time has been reduced, also, from 30 seconds to 20 seconds. It is important to note that this material must be light-cured using halogen light-curing units. According to the manufacturer, the new formulation also demonstrates a dramatic improvement in stain resistance, promoting better esthetics for a longer period of time.
The clinical indications for this liquid polishing material include sealing and polishing direct and indirect composite restorations, provisional bis-acryl and acrylic restorations, and enamel prior to and after orthodontic bracket placement. For composite restorations, the low-viscosity liquid polish may be used to seal/polish/glaze them at the time of initial placement, as well as to revitalize them at recall appointments, returning them to the high-polish appearance that creates vitality in a restoration.
This liquid polishing material is an excellent adjunct to improve the appearance of provisional restorations. Not only does the material reduce the number of polishing steps and improve the visual “vitality” of the restoration,1 but patients will notice improved surface smoothness,2 which contributes to a restoration that is more comfortable and esthetic.
In this case, a bis-acryl provisional restoration was fabricated from a preoperative impression (Figure 1). The restoration was trimmed and finished to the margin, and the occlusion was verified and adjusted in the mouth.
The low-viscosity liquid polishing material was dispensed into a mixing well. A brush was dipped into the mixing well, with care taken not to saturate it. Rather, only a small amount of the material was required.
A thin layer of the liquid polish was applied to the surface of the provisional restoration (Figure 3), and the solvent was allowed to evaporate for 15 to 20 seconds. The restoration was then light-cured with a halogen curing light for 20 seconds.
The final result was a highly polished, smooth provisional restoration (Figure 4). The use of the new low-viscosity liquid polish eliminated the need for multiple polishing steps1 and/or the use of messy polishing pastes. It also allowed for the development of a highly polished surface in far less time.
Dentists looking to improve the esthetics of their composite, bis-acryl, and/or acrylic restorations may find that this new low-viscosity liquid polishing material not only produces a highly polished, stain-resistant surface, but does so with minimal chairtime. To help raise the level of dentistry in the esthetically-focused practice, it is something to consider adding to the polishing armamentarium.
1. Barghi N, Alexander C. A new surface sealant for polishing composite resin restorations. Compend Contin Educ Dent. 2003;24(8 Suppl):30-3.
2. Barghi N, Alexander C. Effect of a sealant on composite resin smoothness and microhardness. IADR. 2003;Abstract #1213.
About the Author
Gary M. Radz, DDS
Cosmetic Dentistry of Colorado