Why are lasers and lights used during professional teeth whitening treatments?
What teeth whiteners do dentists use?
What type of whitener do dentists use when performing professional teeth whitening treatments?
Dentists usually purchase the professional teeth whiteners they use as a part of a bleaching kit or system. The precise composition of each manufacturer's whitener will vary but usually these products contain hydrogen peroxide at a concentration between 15 and 50%. In comparison, at-home teeth whiteners usually contain the equivalent of 3 to 10% hydrogen peroxide. This difference in peroxide concentration is why professional teeth whitening treatments can achieve whitening results much more rapidly.
Manufacturers usually try to formulate their bleaching gels so they have a neutral pH (are non-acidic). This is because teeth are mineralized tissues and placing an acidic whitener on a tooth's surface for an extended period of time could damage it.
It is commonplace that professional teeth whiteners will come prepackaged as two individual components. These components are then mixed by the dentist at the time of use. Usually one of the components is termed the "activator." The idea is that the activator acts as a catalyst that speeds up the breakdown of the hydrogen peroxide into its reactive components. This in turn can speed up the whitening process and enhance its results.
There may be some credibility to this claim. Chemical activation of the whitener could explain why different professional teeth whitening products which have differing concentrations of hydrogen peroxide give similar whitening results.
The fact that a dentist has purchased an in-office teeth whitener as part of a system or kit implies that the manufacturer has created a specific protocol for the use of the whitener. As we have mentioned previously, with some professional teeth whitening systems this protocol includes the use of an "activation" light or laser. Some of the brand names of systems that make use of an "activating" light source are:
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Are bleaching lights or lasers really a necessary or valuable part of professional teeth whitening treatments?
There is a bit of controversy in the dental community as to whether the "tooth whitener light activation" step actually contributes to the teeth whitening process. The manufacturers of light activated whitening products clearly make the claim that the light speeds up the whitening process and makes it more effective.
While the specific rational associated with each company's product differs, the general idea is that the light or laser "activation" triggers a quicker degradation of the peroxide whitener into its reactive components (oxygen free radicals). This in turn speeds up the rate at which the tooth whitening process takes place and enhances the whitening results. If this rationale is accurate it necessitates that a dentist must purchase the manufacturer's bleaching light, an item that can cost many thousands of dollars or in the case of lasers tens of thousands of dollars.
Historically there seemed to be a general acceptance by the dental community that a bleaching light was required. Nowadays there is a realization by dentists that not all clinical studies looking into this matter have confirmed this as fact.
| Several well-constructed studies appear to have concluded that the bleaching compounds used with many professional teeth whitening systems seemed to lighten teeth equally well regardless of whether or not an activation light source had been used. These studies were set up as "split arch" evaluations. This means that the teeth on one side of the person's mouth were treated with just the in-office whitener alone while the teeth on the other side were exposed to both the whitener and the activating light source. As we stated previously, in these studies the evaluators came to the conclusion that the teeth on both sides lightened equally well (both in initial comparisons and at evaluations made one year after the whitening treatment had been performed). |
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For this reason many dentists and whitening product manufacturers alike do not incorporate a light source into their teeth whitening protocol. Some of the brand names of the systems that do not use an "activating" light or laser (or else consider them to be optional) are:
Are there reasons why a professional teeth whitening system should not incorporate an "activator" light or laser into its protocol?
There does seem to be a general consensus in the dental community that there is an association between the amount of heat generated by an "activating" light or laser and the potential for post treatment tooth sensitivity, pain, or tissue damage. However a heating effect produced by bleaching lights may be less commonplace today than it was in decades past.
The thought with professional teeth bleaching today is that if a light source is used it should be one that generates less heat than those lights of previous generations. Whereas historically light sources were known to have potential for producing significant temperature changes (that was the whole idea, a warmer whitening solution produced a faster breakdown of the hydrogen peroxide into its reactive components), today's lights have less potential for creating this heating effect (typically because a filter is used to remove the infrared emissions of the light). Less heat during the whitening treatment makes it less likely that tooth discomfort or tissue damage will be a concern.
