Clinical Application of a New Extended Range Composite Material
Kimberly Marshall, DDS; Gene Brooks, DDS; Thomas G. Berry, DDS
In the last decade or so, several companies have introduced resin composite systems that incorporate a wide range of shades along with various translucencies that allow an excellent match with tooth structure. Some of these new systems have included many variations in shades and degrees of opacity and translucency. These systems allow marvelous shade matching but the color selection system is complex enough to require a significant learning curve to achieve the product’s full potential.
While these systems do provide the potential for excellent esthetic results to satisfy the expectations of the most exacting dentists and the most demanding patients, many dentists find that the systems exceed the practical demands of the majority of their patients. As a result, some companies have reversed this trend of offering systems with more shades and translucencies. Their attention turned to materials that provide enough variation to meet the demands of the majority of their patients but without the extra choices provided by more extensive systems. This article discusses the use of one of these products recently introduced to the market.
The Product
VOCO America (Sunnyside, NY) now offers a product named Amaris®. It is supplied in either unidose compules or syringes (Figure 1a and Figure 1b). This light-cured composite is advertised as a nano-reinforced material that is 80% filled by weight. Amaris contains 20 nm to 60 nm silica nano-particles as a filler. It is offered in five basic dentin shades, a bleach shade, and three translucent shades. It has opalescence and fluorescence and can be finished to a high luster. The general physical properties, as stated by the manufacturer, compare favorably with other well-received products on the market. The flexural and compressive strengths, as listed by the manufacturer, also compare well to other products, so good wear resistance is anticipated although no long-term clinical studies have yet confirmed this.
Data released by VOCO indicate that shrinkage is a relatively low 2%. Studies of other well-accepted composite systems have shown their polymerization shrinkage ranges from 1.5% volume to as high as approximately 7% volume for flowable composite depending on the specific material.1 Other resin composites currently on the market are advertised as having volumetric shrinkage ranging from 2% to slightly over 2.25%. This level of shrinkage leads to the supposition that microleakage will be comparatively low.2 The material provides good radiopacity.
Handling Characteristics
The manufacturer advertises the product as non-sticky and non-slumping with a smooth consistency. The listed working time of 8 minutes allows sufficient time for placing and sculpting the restoration. The authors found the material a bit stiff, but it did appear to adapt well to the cavity walls and it held its shape as the anatomy was formed. There was no noticeable tendency to slump.
Clinicians may find that warming the compules/syringes by placing them in a device such as the Calset Unit or in a warm water bath will help to make the material a bit easier to handle and may enhance its physical properties.3,4 However, as the material is manipulated, it becomes less viscous and easier to shape. The viscosity should not be a problem.
The flowable material is packaged in syringes. It is very fluid so it flows quite easily. This enables it to fill in the “hard-to-reach” areas easily to minimize the likelihood of voids. However, its very low viscosity can prove to be a problem in confining it to the target areas only. Care must be exercised that it does not tend to flow beyond the target surfaces. As is always the case with flowable composite, there is less filler content so greater polymerization shrinkage is expected as compared to the basic restorative material.
Shade Selection
The material is offered in five opaque shades and three translucent shades. The shade designation system does not use the traditional shade guide designations of A1, A2, B1, etc (Figure 2). It lists the opaque (body) shades as 01, 02, 03, 04, and 05. These shades correspond essentially to A and B shades in other systems, starting with 01 as the highest value and 05 as the lowest value. They are relatively opaque and do a good job of matching the dentin. The three translucent shades are listed as TL (translucent light), TN (translucent neutral), and TD (translucent dark). The flowable material is supplied in special shades referred to as HT (high translucent) and HO (high opaque).
There was no problem with matching the basic shade of the tooth being restored. The basic shades combine with the chameleon-like properties of the resin composite to mimic the tooth color well. The kit provides both an opaque shade to disguise discolorations and a translucent shade to create an “enamel” surface layer. For all but the most demanding situations, these shades and opacities allow very good esthetic results. It may be a bit more difficult to achieve especially complicated effects for the most esthetically conscious patients with the limited shades available.
The placement of a posterior restoration is included to illustrate the clinical use of the material.
Clinical Procedure
The patient reported with recurrent caries around the occlusal margins of a large existing disto-occlusal composite restoration that had been placed several years previously (Figure 3). The tooth was vital and asymptomatic. Radiographs revealed good adaptation of the distal portion of the restoration with no evidence of any caries along the gingival margin of the restoration. Shade matching demonstrated that shade 02 matched the tooth structure, although the material appeared to have slightly higher value when placed than indicated by the shade guide. After the patient was anesthetized, a dam was placed to isolate the tooth from saliva and other contaminants.
The occlusal portion of the restoration and the recurrent caries were removed. Considerable recurrent caries had occurred because of leakage around the occlusal margins of the old restoration. Visual examination using loupes indicated that the proximal portion of the restoration displayed no carious activity or marginal staining and that it appeared well bonded to the tooth. Therefore, the proximal portion of the restoration was left intact. The shape and extension of the preparation were dictated by the failing restoration and the caries lesion. The occlusal margins were not beveled (Figure 4).
The preparation was acid-etched with 37% phosphoric gel, thoroughly rinsed, and then lightly dried. Amaris is advertised as being compatible with bonding agents from other companies, so OptiBond® Solo Plus (Kerr Corporation, Orange, CA) was applied to enamel and dentin surfaces and cured for 20 seconds. A second coating of bonding agent was similarly applied and cured to ensure full bonding to the cavity surfaces. Opaque Amaris flowable composite was placed to offer better adaptation to the cavity walls and to the re-maining composite restoration on the distal surface (Figure 5). Care was taken to confine the flow of the material to the target areas. The flowable composite was cured for 40 seconds with a LED curing unit at an intensity of more than 600 mW/cm2. Shade 02 composite was placed into the floor of the cavity preparation in a layer approximately 2 mm thick to ensure optimal polymerization.5 The increment was checked for potential shade match. The material was adapted to the cavity walls before curing it for 40 seconds (Figure 6). An additional layer of Shade 02 composite was placed and cured in the same way as the first layer. Although Shade 02 material is a dentin mimicking material in its degree of opacity, some influence from the surrounding tooth color helped to blend the material with the tooth shade.
The last dentin layer was shaped to begin forming the initial triangular ridges, fossae, and grooves before curing the composite. The next increment represented the enamel layer and created the general occlusal anatomy. HT shade (high translucent) was chosen because it was thought that the shade chosen for the dentin layer matched the tooth well and needed only a translucent layer to provide the desired appearance (Figure 7). After this layer was placed and cured, the restoration was given a final shaping with finishing burs to add some detail, reduce areas of premature occlusal contact, remove supra-marginal areas, and begin the smoothing process. Final smoothing was accomplished with Shofu finishing points and cups.
The cavo-surface margins were again etched with 37% phosphoric acid for approximately 10 seconds, rinsed and dried, and resin (OptiGuard, Kerr Corporation) was applied to the margins. This was done with the intent to provide some additional sealing to the cavo-surface margins (Figure 8). At 4 weeks post-placement, the patient reported no discomfort or sensitivity.
Conclusion
The Amaris resin composite restorative material proved to be easy to handle, cure, and finish to the desired surface texture and shine. The shade variations and different opacities supplied in the kit by VOCO allowed an easy match to the tooth color. The patient was well satisfied with the esthetic results.
References
1. Feilzer AJ, De Gee AJ, Davidson CL. Curing contraction of composites and glass-ionomer cements. J Prosthet Dent. 1988:59:297-300.
2. Kleverlaan CJ, Feilzer AJ. Polymerization shrinkage and contraction stress of dental resin composites. Dent Mater. 2005;21: 1150-1157.
3. Daronch M, Rueggeberg FA, De Goes MF. Monomer conversion of pre-heated composite. J Dent Res. 2005;84(7):663-667.
4. Bortolotto T, Krejci I. The effect of temperature on hardness of a light-curing composite. J Dent Res. 2003;82(Special Issue A): Abstract 119.
5. Choi KK, Condon JR, Ferracane JL. The effects of adhesive thickness on polymerization contraction stress of composite. J Dent Res. 2000;79: 812-817.
About the Authors
Kimberly Marshall, DDS
Assistant Professor
Department of Restorative Dentistry
University of Colorado School of Dental Medicine
Aurora, Colorado
Eugene Brooks, DDS
Assistant Professor
Department of Restorative Dentistry
University of Colorado School of Dental Medicine
Aurora, Colorado
Thomas G. Berry, DDS
Professor
Department of Restorative Dentistry
University of Colorado School of Dental Medicine
Aurora, Colorado
