Success in Tooth Whitening and Shade Matching





By Back Mike Wong October 30, 2018

Teeth are pretty front-and-center when it comes to facial esthetics, but they can become discolored for a number of reasons. The usual suspects include things like tobacco, tea, coffee, red wine, fruit — basically anything that is high in tannins, acids or chromogens can cause stains or dull enamel to the point that it stains more easily.

Because most of us equate white teeth with beauty and health, today’s clinicians would probably be hard pressed to think of a time when tooth whitening services weren’t in demand. Whether placing direct or indirect restorations, savvy clinicians recognize the importance — and the intricacies — of shade matching. After all, patients are likely to want the repairs to match the rest of their teeth.

The Pursuit of White Teeth

While patients can come to the dentist’s office for light-activated whitening treatments, they can also whiten their teeth at home. In fact, sales of DIY whitening products, such as bleaching gels and trays, and whitening toothpastes, strips, and even gum, are expected to continue on an upward trajectory into the near future. 1ReportLinker. Tooth Whitening Products Market Size, Forecast and Trend Analysis, 2014–2014. Available here. Accessed September 20, 2018.

But while the quest for the megawatt smile continues, some experts caution tooth whitening is not without risks. The bleaching agent, either hydrogen peroxide or carbamide peroxide, can be hard on enamel as well as oral tissues if misused, and can also cause dentinal sensitivity. 2American Dental Association. Tooth Whitening/Bleaching: Treatment Considerations for Dentists and Their Patients. Available here. Accessed September 20, 2018.

Tooth Whitening Precautions

For reasons such as these, the American Dental Association (ADA) advises patients seeking whiter smiles consult their dentists before going the OTC route. In fact, although the ADA agrees that home whitening products are mostly effective and safe, the organization raises concerns about possible links between home bleaching with high-concentration hydrogen peroxide and cellular damage to tooth structure, pulp tissues and mucosal tissues. The ADA also stresses the importance of proper isolation during in-office bleaching, to protect mucosal tissues. 3American Dental Association. Tooth Whitening/Bleaching: Treatment Considerations for Dentists and Their Patients. Available here. Accessed September 20, 2018.

It is for such applications that systems such as Isolite come in handy. Courtesy of its flexible, transparent mouthpiece, Isolite can guard patient airways and keep agents from contacting soft tissues, while providing suction, retraction, lighting and a patient-friendly bite block. This can greatly enhance safety and comfort during procedures such as whitening.

But tooth whitening is likely to be ineffective for cases in which discoloration is caused by an issue inside tooth structure, such as shadowing from a root canal treatment, caries, or from other kinds of intrinsic factors. Instead, composite restorations or veneers might be more appropriate options. In these instances, proper isolation is also critical and can make the difference between material success and failure. 4American Dental Association. Tooth Whitening/Bleaching: Treatment Considerations for Dentists and Their Patients. Available here. Accessed September 20, 2018.

Shade Matching

Using traditional or digital shade guides, dentists can approximate the correct shades and gather information about the various hues and shade layers in one tooth. But while shade taking, clinicians must be mindful of the environment in which the match is being made, as everything from lighting to clothing color can affect the outcome. 5Stone R. Leave no trace. Mentor. 2017;8(7):18–22.

Clinicians realize that teeth are not opaque blocks of white. And, especially in the case of indirect restorations, this is where artistic skill pays off. By layering shades and building in nuanced characterizations and translucencies, clinicians — or their lab partners — are, indeed, creating small, functional masterpieces.