Over the Counter Whitening Agents: A Concise Review 2/23/11

Department of Pediatric Dentistry
Resident’s Name: Murphy Program: Lutheran Medical Center - Providence
Article title:Over the Counter Whitening Agents: A Concise Review
Author(s): Flavio Demarco PhD, et al
Journal: Brazilian Oral Research
Year. Volume (number). Page #’s: 2009. vol 3 NO 1 64-70
Major topic: Whitening agents
Minor topic(s): OTC agents, side effects
Main Purpose: To evaluate and discuss the current knowledge concerning efficacy, mechanism of action, and legislation of OTC tooth bleaching agents
Overview of method of research: Review

Findings:
The big buzz word in dentistry is ‘esthetic dentistry’. Tooth discoloration is of course, not esthetic. Tooth discoloration can be caused by either intrinsic (stains in enamel/dentin relative to their properties) or extrinsic stains from food, drink, etc. Everything from microabrasion to bleaching can be used to try to remove such stains. Dentist supervised home-use bleaching custom trays is the most common procedure dispensed by dentists. Usually, this involved custom made suck down trays that are filled with 10% carbamide peroxide and worn at night for +/- 2 weeks. While 10% is the most common concentration used (and the only conc. Accepted by the ADA), conc. Of 15 and 20% can also be used. Most adverse affects reported for at-home bleaching systems are tooth sensitivity and gingival irritation, which both disappear when the agent is stopped or removed with sodium fl.

In addition to bleaching that is overseen by dental professionals, there are many OTC tooth whitening systems available on the market today. The OTC systems may also cause side effects, and may not be as efficacious as the systems offered by dental professionals. For whitening to be considered clinically significant it must have a value of 4 units gained on the vita shade guide.

Whitening Tooth Pastes
More than 50% of the products rarely contain CP, HP, or any kind of bleaching agent. In actuality, the paste is filled with abrasives that remove superficial stains on the teeth instead of ‘whitening’ them. Active components include enzymes that break down the organic molecules of the biofilm. These pastes can be dangerous because of the high amount of abrasiveness, which could lead to excessive wear of enamel and dentin. The whitening is not clinically significant.

Rinses
Generally these contain a low con. Of HP, 1.5%. Studies have shown that systems utilizing trays are much more effective than rinses. The whitening observed with rinses, if any, were not clinically significant.

Whitening Floss and Tooth brushes
Allegedly, whitening floss can remove stains at the gingival, subgingival, and interproximal areas. As with the pastes, the floss has a high amount of abrasives in it to remove staining, while whiteneing is not clinically significant. With regards to tooth brushes, studies have shown that power tooth brushes showed a better ability to maintain whitening as opposed to traditional brushes.

Chewing Gum
Gum with sodium hexametaphosphate 4-7.5% has been introduced, claiming to do the job. However in clinical trials, when compared with gums containing nicotine, the nicotine gum did a better job of whitening extrinsic stains.

Paint on Gels
Gels or varnishes that have HP 6% or CP 18% can be brushed onto the teeth. Again, when compared to the tray systems, the paints/gels did not do a good job, however it was seen that HP worked better than CP.

OTC tray activated by light
New product that is light activated. NO active ingredient listed. Needs more research/info.

Whitening strips
Filled with HP 5-15%. Worn for 5-60 min at a time for 28 days to give the best result. Can get clinically significant results with less side effects than the trays. Because strips are effective and relatively cheap, ranging in cost from $2-$35, most people are using them as opposed to going to a tooth whitening center where the cost may be $400.

Safety Guidelines
In 2005, 2 billion dollars was spent on OTC whitening agents. The pharmaceutical companies invested twice as much in marketing as they did in research... so buyer beware. It is recommended that bleaching only be done in children age 15 and older. In Europe, .1-6% HP is only considered safe when administered under a professionals care. The ADA says that OTC agents are safe, but should be used under a professionals supervision.

In relation to carcinogenesis, high conc of HP may act as a promoter or oral lesions together with other agents such as alcohol and tobacco, but low conc of CP are safe. Never drink any peroxide agents.

Addiction to whitening agents is common. Many people over self medicate. The ‘bleachorexics’ or ‘whitening junkies’ repeatedly use the agents without the care of a professional, and often cause themselves harm. Something to be aware of.

Key points/Summary:
1. Whitening pastes, floss, and brushes remove superficial stains, and are not bleaching agents.
2. Paint on gels and rinses have low levels of bleaching agents and do not produce clinically significant results.
3. Whitening strips can produce an effect similar to 10% CP in a tray, however more long term research is needed.
4. Legislation varies from country to country. Clinicians need to be aware of available products, and that abusive self medication is possible and can cause harmful effects.
5. More research is needed.

Assessment of Article:
Very thorough review. It’s always tough to summarize a summary. Excellent info for boards, especially since the last few years there have been a lot of questions on bleaching.