These days, when selfies are snapped at every turn, only to be blasted across the internet at lightening speed, appearance is at a premium. And this digital presence doesn’t stop at outward beauty. Haute couture also extends to teeth. After all, perfectly painted lips are all for naught if they frame a less than perfect set of teeth.
There’s no doubt that esthetics is big in dentistry. In fact, a recent report projects continued industry growth in the United States that will approach $30 billion by the year 2024, due, in part, to an aging generation of baby boomers.1 Of course, nowadays, you’d be hard pressed to find a dental office that doesn’t offer “esthetic dentistry” — even if it doesn’t use the words “esthetic” or “cosmetic” in its practice name or marketing slogan.
But there is more to esthetic dentistry than just glow-in-the-dark whitening. The best restorations — whether direct or indirect — are those that mirror natural dentition and lifelike esthetics. And this requires more than fairy dust.
What began, years ago, as a questionable departure from the tried and true amalgam fillings, composites have evolved. Once weak, monocolored restorations lacking polishability, composites now offer lifelike and highly polished esthetics.
Ron Kaminer, DDS, a well-known author, educator and lecturer, who operates practices in Hewlett and Oceanside, New York, says it’s helpful to view changes in esthetics and cosmetics from the perspective of material and technology. “From a material perspective, manufacturers are making material with smaller particle sizes and different fillers that all contribute to the wear and esthetic characteristics of the material,” he notes. “The latest generation of composites polish better, stain less frequently and wear longer due to their inherent characteristics.”
These characteristics often have to do with nanotechnology and the science of combining shapes and sizes of filler particles — down to microscopic sizes — to render composite materials that are both strong and esthetic. Other characteristics being formulated into some of the newest composite materials include bioactive properties, which, as Kaminer notes, increase resistance to decay and staining.
Similarly, materials for indirect applications have made significant gains over the past several years. Although porcelain is still considered top echelon for anterior applications — and is still used with metal copings for posterior restorations — all-ceramic restorations are gaining traction as the choice du jour in many dental practices. Composed of a single material, such as zirconia or lithium disilicate, all-ceramic restorations are increasingly natural-looking for high-end esthetics. Many offer translucency variations, can be fabricated from blocks either at the lab or in the office via computer-aided design/computer-aided manufacturing (CAD/CAM), and then can be stained and glazed to match surrounding dentition.
In the opinion of Grant Williams, DMD, a general and esthetic dentist based in Pacific City, Oregon, “The most significant recent advancement in cosmetic/esthetic dentistry is the development of monolithic ceramics, such as zirconium and lithium disilicate. They are very strong, very esthetic, well accepted by the soft tissue and not abrasive to the opposing dentition. And they can be milled from a three-dimensional (3D) scan or pressed.”
Williams adds that this isn’t the only boon to esthetic treatments. “Other advancements range from ultrathin porcelain veneers that require little or no tooth preparation, which supports minimally invasive dentistry, to tooth whitening that takes less time with minimal tooth sensitivity. Eliminating dark crown margins with porcelain butt margins or all-ceramic material has also been a huge plus to esthetic/cosmetic dentistry,” Williams tells Mentor.
To create this brand of magic, savvy clinicians stock their armamentariums with an assortment of products. Williams ticks off a list that includes porcelain etchant, silane, cleaning paste to remove phosphate saliva contamination from a ceramic crown, phosphoric acid etch, veneer luting resin, unfilled resin, resin modified glass ionomer cement, filled resin of various shades including bleach shades, flowable composites, self-etching flowable composites, shade guides, #12 scalpel blades, an assortment of finishing burs and polishers, and, of course, a curing light.
In addition to materials and basic instruments, digital technology is making major inroads into esthetic dentistry. “We can show our patients what their potential smile could look like through the latest digital scanning software and from outside digital design services,” says Kaminer. “Clinicians can take a scan and either design a potential smile themselves or have a service do it for them, allowing patients to visualize their enhanced smile before any work commences.”
The VITA shade guide, an industry standard since the 1950s, offers progressions of shades that are labeled A1, A2, A3, B1, B2, etc. When a dentist matches one of these shades as closely as possible to a patient’s teeth, it provides a frame of reference, and helps smooth communication with the lab in the case of indirect restorations. But with the advent of new materials and corresponding proprietary shade guides, things have gotten complicated.
“If you take 10 shade guides and you take all the A1s out of those shade guides, they won’t necessarily match each other,” says Robert Lowe, DDS, a dentist based in Charlotte, North Carolina. “To make matters more challenging, composites from various manufacturers may not match the shade guide designation either. So for me, the goal of using a shade guide is to get me in the ballpark.”
Lowe says he prefers newer shade guides, such as the VITA 3D guide, that base color selection on value (lightness and darkness) first. “You can have something that’s slightly off in hue (color) or chroma (saturation), but if the value is off, it’s not going to work,” Lowe explains. The inherent problem, he adds, is that there must be a conversion to VITA Lumin shades, which are more widely used, if you are not using the corresponding shade guide porcelain.
There is still no exact way to match a single tooth for either direct or indirect restorations. Even the lab technician’s shade guide may differ from the clinician’s.
In this regard, says Lowe, “The use of digital photography is going to help both the dentist and the technician, and one camera has recently become available that is specifically designed to ease this process.”
ART AND SCIENCE
According to Robert Lowe, DDS — a Charlotte, North Carolina-based dentist and widely recognized author and lecturer — technology in restorative dentistry can be a double-edged sword. “It can be both good, by reducing the time and manpower required to produce an indirect dental restoration and bad,” Lowe says, “in that a lot of the art is going out of our profession because we are delegating that art to technology, whether it be computer design or total milling.”
But for Lowe, the duplication of nature is still an artistic endeavor. “To me,” he says, “the most beautiful ceramic veneer or crown is still handmade by a technician, layering in different colors and effects to mimic the opacities and translucencies of nature. And that’s not yet something that you can build into any type of block or computer design system with the same level of realism.”
Lowe notes, however, that artistic skill continues to be demonstrated in the placement of direct restorations, which are still placed by hand. “The materials are certainly getting better from the scientific standpoint, as far as shrinkage, physical properties, and also in esthetic quality and polishability,” he says.
A primary difficulty with making direct composites esthetically realistic stems from the fact that enamel and dentin have different optical qualities. “I think most of the esthetic restorations still come from layering with different opacities to more closely follow nature,” Lowe opines. “That’s still quite an artistic endeavor, particularly when you’re talking about anterior composites.”
Indeed, systems are available based on this type of artistry that allow the layering of composite in various translucencies and shadings. They even offer the ability to build in characterizations, such as mamelons, for an ultrarealistic look.
In the creation of direct esthetic restorations, clinicians agree that matrix systems are key. “Matrix systems are important when attempting to restore ideal contacts and contour between teeth,” says Williams. “Poor contacts and contour can create food traps that lead to decay and periodontal problems. Proper restoration shape, size, and contour contribute to a natural and esthetic smile. The right matrix system can help make this easy and predictable.”
Lowe agrees. “Shape, form and contour are more critical than color for good esthetics. Natural teeth are not all the same color, so even if the restoration color isn’t perfect, as long as the shape and form closely mimic the natural tooth it will look like it’s part of the patient’s natural dentition,” Lowe shares. “When placing a direct composite, the fit of the matrix is critical because it limits the amount of material and confines it to make it easier to get the proper resulting shape.”
But the type of matrix system used can also signifigantly impact restoration success. Lowe believes that too many dentists still rely on Tofflemire matrices for composite, even though they are designed for use with amalgam. The problem with using a Tofflemire matrix system with composite material lies in the fact that Tofflemire bands are flat. And while amalgam condenses, it can be pushed against the metal Tofflemire matrix bands to build in curvatures. This does not hold true with composite.
Lowe explains, “In posteriors, the proximal surfaces are convex. In my opinion, sectional matrices are absolutely the best to get a good esthetic result because they have the inherent shape of posterior teeth in the proximal aspect. But many clinicians are still using the same technologies they’ve used for years, and then they struggle to obtain esthetic results because it’s really dependent upon their own freehand artistic ability — which can vary greatly.”
Point of Sale | The Right Stuff
Most dentists today can benefit from keeping a range of esthetic materials within reach.
- For indirect applications, all-ceramic materials allow both strength and beauty, as well as increasing realism.
- Direct restorations can benefit from the artistic application of layers of composites that lend various shadings, opacities and opalescence.
- Matrix systems are critically important for both posterior and anterior applications.
- Finishing and polishing are important steps for enhancing esthetics and protecting oral health.
- Shade guides help approximate restorative color, though they may only provide a starting point.
FRONT AND CENTER
Due to their shapes and lack of occlusal surfaces, anterior direct restorations call for different types of matrices. Says Lowe, “Most schools still teach the use of flat Mylar strips as matrices for Class IIIs and IVs. But again, those proximal surfaces are not flat. And in today’s world of esthetics, flat proximals lead to black triangles, which lead to unhappy patients.”
Lowe indicates that one matrix can achieve natural convexity and emergence profile. He adds that another system is available that recreates the subtle anatomy on the facial aspect of the anteriors, and also serves as a matrix to restore portions of front teeth on the facial surface.
Aside from helping to ensure a good final contour, another benefit offered by matrix systems for both posterior and anterior applications is realized in finishing and cleanup time. Matrices help contain material rather than allowing it to flow all over the place, becoming what is known as “flash.” So the use of a matrix system can shorten finish time. Additionally, this helps eliminate the problems of overhangs and residual material, which can cause gingival irritation.
“My goal when I do a posterior composite is to do as little rotary finishing and polishing as possible,” says Lowe. “That means the matrix has to not only contain the material, but it has to be at the proper height to the adjacent tooth and the vertical margins of the preparation need to be sealed 100% so there are no overhangs and excess to remove. Unlike amalgam, which you can carve, once you cure composite with the light, it’s set. And the only way you can get rid of that excess, hard composite is with a rotary instrument, which is difficult,” Lowe explains, adding, “Rotary instruments are round, so they gouge and leave concave imprints where you want to end up with a convex surface.”
Black triangles: Gap that appears between teeth, next to the gingiva.
Cosmetic dentistry: Dental treatment that improves appearance; often used interchangeably with esthetic dentistry.
Class III and IV: Restorations on proximal surfaces of incisors and bicuspids; the latter involves the incisal edges.
Porcelain etchant: An agent that creates tooth in porcelain to improve adhesive bond.
Proximal: The surface of a tooth that faces the neighboring tooth, whether mesial (front) or distal (back).
Mamelons: The round-edged protuberances seen near the incisal edge of incisors.
Silane: A coupling agent used in composites to link fillers and matrix.
FINISHING AND POLISHING
Regardless of how much composite is left to clean up, finishing and polishing are also paramount to success. And it’s not just for looks. Smooth, highly polished surfaces provide a poor substrate for bacterial growth. “While finishing and polishing have gotten easier due to better properties of the composites and to better polishing materials, it remains the most tedious, yet important, part of most bonding procedures,” says Kaminer. “It’s important to finish and polish well, as this will reduce or eliminate imperfections in the material that may have occurred due to placement. Finishing and polishing not only improve esthetics and increase longevity, but they also make the restorative material less vulnerable to stains and marginal failure.”
Finishing involves gross removal of excess material and shaping the tooth. Polishing adds a protective and esthetic gloss to the finished tooth. To accomplish these tasks, clinicians must have a range of burs on hand. Kaminer notes, “Most practitioners use a combination of finishing carbides, maybe diamond burs and a combination of impregnated discs and cups in various shapes and sizes.” Finishing and polishing instruments are often available in kits geared to address particular types of restorative materials. Many of today’s clinicians opt for tungsten carbide instruments for these processes. But for polishing zirconia restorations, diamond instruments are invaluable, as zirconia is second only to diamond in hardness. These instruments feature everything from coarse to superfine grit. Aside from crushed diamonds, other types of abrasives include aluminum oxide and silicon carbide.
The general picture of today’s esthetic dentistry that emerges is one of access to beautiful teeth for everyone, including patients who have long lacked the confidence to smile. And as the cutting edge continues to sharpen in esthetic materials and digital technologies, more clinicians may find that placement of natural-looking esthetic restorations is becoming second nature.
- Grand View Research. Market research report: Cosmetic dentistry market analysis. Available at: grandviewresearch.com/industry-analysis/cosmetic-dentistry-market. Accessed December 26, 2017.
Featured Image by PEOPLEIMAGES/E+/GETTY IMAGES PLUS
From MENTOR. February 2018;9(2): 20-22,24-25.