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• Reservoirs Not Really Needed

  • Dental Economics - Michael Miller, DDS

    Are reservoirs really necessary for home bleaching trays? I have read in REALITY that your "own clinical study suggests reservoirs are not necessary and may even be contradicted in come patients." Could you please elaborate on this?

    We did a "split mouth" study of 21 patients who bleached with trays that had reservoirs on the right side, but no reservoirs on the left. Approximately one week after bleaching was ended, we evaluated the patients. The results showed no visible differences between the reservoir and non reservoir sides. Therefore, we concluded that reservoirs do not increase the efficacy of home bleaches, including Nite White, Excel 2, Opalescence PF, Zaris, Day White 2, Rembrandt Xtra Comfort, and Hi Lite 2.

    Other reports are surfacing that agree with our results. One issue that still remains, however, is how quickly the bleaches degrade. It has been suggested that most bleaches work best during the first hour of treatment and should be replenished or discontinued at that point. The patients in our study bleached for short and long periods of time without any apparent differences.

    Dr. Miller is the publisher of REALITY and REALITY Now, the information source for aesthetic dentistry. He is an international lecturer and a fellow of the American Academy of Cosmetic Dentistry, as well as a founding member. He maintains a private practice in Houston, Texas.

• The ABC's of Sensitivity

  • The Sensitivity Issue Through the Eyes of a Registered Hygienist - Victoria DeCosta, RDH

    Have you ever had sensitivity when bleaching your teeth? Not fun is it? Whether you have or not, you already know you don't want your patients to go through unnecessary discomfort. The fact is, sensitivity is a reality of tooth whitening for some patients regardless of the bleaching products or the concentrations used. Brushing up on the ABCs of bleaching sensitivity can help you better understand the A) SYMPTOMS, B) CAUSES, and C) SOLUTIONS, and can help you maximize your patients comfort.

    Start by identifying the actual symptoms. Is this a case of soft tissue irritation or pulpal (dentin) sensitivity?

    Soft Tissue Irritation
    Concentrations higher than 15% can cause soft tissue irritation. The symptoms are tingling or stinging of the gums or the appearance of small blanchings or tenderness. There are three causes of soft tissue irritation. The first is an overlapping tray. Care should be taken to trim the tray away from the soft tissue. The second is overfilling the tray, which is a common mistake of many patients. Instruct the patient to decrease the amount of gel in the tray. Less is best! The proper dose is a small drop in each tooth indentation for a total of only .25cc (10-12 drops). Finally, soft tissue irritation is often caused by food, floss, or toothbrush cuts and abrasions. Such wounds need to heal before whitening.

    Pulpal Sensitivity
    The symptoms, causes and solutions for pulpal/dentin sensitivity include tooth dehydration and/or acute sensitivity. Tooth dehydration symptoms may come in the form of a dull toothache or a headache. Using short-term modality (20-60 minute treatments) should avoid this problem. By the end of the first hour, the carbamide peroxide of all major brands has been expended by approximately 70% (Clinical Research Associates Newsletter, Tooth Bleaching, state-of-art 1997). Wear beyond that point does not effectively whiten but continues to keep the teeth coated with gel-continuing to dehydrate the teeth. Short-term modality allows rapid saliva re-hydration to quickly counteract the hydrostatic imbalance created by the peroxide in the dentin tubules and enzyme systems in the pulp. One answer for patient discomfort is taking a break for a day or two and/or cutting back the treatment time.

    Another type of pulpal sensitivity is acute sensitivity. When the patient has a history of acute pulpal sensitivity or is experiencing severe sensitivity, it is being caused by direct access to the dentin from recessed gums, enamel fractures, a chipped tooth, leaking margins, etc. The pain comes in the form of a jolt or shock from a single tooth. In these cases, a fluoride toothpaste is recommended for use two weeks prior to whitening and then throughout the treatment. A common pain reliever such as aspirin or ibuprofen is also a good strategy for acute sensitivity due to exposed dentin.

    Whether the sensitivity is from soft tissue irritation or pulpal sensitivity, have the patient take a break in the treatments for a day or two to allow him/her to normalize. Then make the appropriate diagnosis and adjustment and continue treatment. Those who experience discomfort will most likely not have the prior magnitude of discomfort.

    Sensitivity is based on the patients' perception, which can be positively affected by you. Helping the patients categorize the sensations that are experienced during whitening treatments can help them put what they feel into proper perspective. Remind them it is safe. Tell them that bleaching gels whiten much like cosmetologists color or lighten the hair of millions of people. Cosmetologists use 10% to 40% hydrogen peroxide, while dentists whiten teeth with at-home strengths from 3.3% to 10.5% hydrogen peroxide. Literally millions of people have had their teeth safely whitened--a magnitude of safety rarely enjoyed by other cosmetic procedures. Carbamide peroxide is prescribed to treat gums and combat gingivitis. Under professional supervision, whitening is safe and effective. Inform your patients what to expect. Keep in mind 15%-20% of your patients will experience sensitivity wearing the tray alone. Another 15% on top of that will experience sensitivity with a placebo in the tray. Your awareness of these varied sensitivity ABCs will help your patients get the best results with the least amount of discomfort.

• The BS of Tooth Whitening

  • What to Believe and What not to Believe - Rodney Ogrin, DDS

    What to Believe and What not to Believe, The Basic Science of Whitening, or Bleaching Science, has come to prove that in tooth whitening as in most things, keeping it simple is the very best medicine

    Many dental products provide a challenge to clinicians because, with only marketing information to guide them, they must judge between those that are "new" and better and those that are just "new". Due to strict competition and the rush to be first on the market, dentists and their patients often become test data for new products. With tooth whitening, there are many products available, but how do you choose which are just hype and which work? With this article you will be armed and ready to make informed decisions for both you and your patients.

    The science is basic--carbamide peroxide safely and effectively whitens teeth. This has been recognized and accepted for over a decade by legions of patients. In the quest to find the best way to use carbamide peroxide, different ingredients, modalities, and other innovative ideas have been tried. Many of those have ended up complicating the issue, but have served to help us learn more.

    Many theories have not fared well when subjected to the realities of Bleaching Science. Reservoirs, KNO3, and "time-release" agents have been brought to bleaching in support of long term modality. Overnight or multiple hour treatments have turned out to be not in the patients' best interest. According to the 1997 CRA Newsletter Tooth bleaching, State-of-Art, reservoirs or not, 70%-80% of the active ingredient of all major brands is spent by the end of the first hour of bleaching. Treatment times longer than one hour do not effectively whiten but instead result in dehydrating the teeth, causing unnecessary sensitivity issues. Adding KNO3 was an attempt to overcome these sensitivity issues that are handled much safer with short term modality. If long term modality bleaching is unnecessary then we must conclude reservoirs are also not necessary, but instead waste valuable laboratory time.

    Another theory that at one time seemed the next logical step is chair side lights. Lasers, hot lamps and cold lamps add flair and increase the cost, but every study conducted on the subject have concluded that these expensive lights do not get any better results (ie: CRA Newsletter, New Generation In-Office Vital Tooth Bleaching, November 2000). The heat from these lights may accelerate the whitening process, but only a few minutes of time is actually saved, and this heat can actually cause some soft tissue burning. Lamps are good for "sizzle" and may impress some patients, but are a risk for pulpal damage and do little for the actual procedure.

    Another issue in tooth whitening is tasty flavoring. Flavoring was originally developed for children's products, particularly fluoride, a product that runs onto the tongue. In tooth whitening, if you taste product you have used too much and could be blanching your gingiva. Taste is a warning, not for enjoyment.

    There is a common notion that higher concentration carbamide peroxide means greater sensitivity. While this is true for soft tissue, it is simply not the case for pulpal sensitivity. However, the soft tissue sensitivity issue is moot if the whitening trays are scalloped on the gingival margins so no product comes in contact with the soft tissue. When it comes to pulpal sensitivity there are only two sources, access to the dentin and/or dehydration. Contrary to common thought, the higher percentages can actually help avoid pulpal sensitivity-- through shorter wear time, leading to less dehydration and quicker rehydration. Sensitivity due to the gel seeping into the dentin from recessed gums, enamel fractures or leaking margins has no gradient ratio of discomfort in higher percentages-in these cases there will be some discomfort with any percentage.

    So there you have it, the Bleaching Science. Mix this with your dental common sense and you are armed and ready to make informed decisions for your patients.

    Dr. Rodney Ogrin, DDS, is a consultant and a pioneer of tooth whitening for more than 27 years. He began his career studying full mouth reconstruction and began to focus on cosmetic dentistry in 1985. He began dedicating himself to tooth whitening in 1990.

• The Battle of the Percentages

  • The Patients' Best Interest is the Bottom Line

    The discovery of modern tooth whitening began with dentists prescribing low levels of peroxide to battle periodontal diseases and discovered their patients teeth were getting whiter in the process. As word spread, dentists began marketing the idea of tooth whitening and it caught on. As competition grew, an increase in strength of the product was needed to meet the demands of patients wanting whiter teeth faster. Higher concentrations sparked debates about sensitivity concerns. As these higher percentages were put to the test in some dental offices, we learned that higher concentrations were safe and effective, quieting the concerns.

    Now we have strengths up to 30% carbamide peroxide for take-home, used safely by hundreds of people each year. Depending on your patient, their motivation, expectations and ability to follow instructions, the choice of percentages is yours. Whether the patient whitens with 10%, 15%,20%, or 30%, you will see results. However, it may take longer with the lower concentrations to achieve the patient's desired whiteness. Below are a few guidelines to help you when selecting the best percentage for individual patients and your practice.

    10% Treatments: 2 daily, 1 hour Common Use: Whitening, Cleaning and debriding. First used to battle periodontal disease. Trim the tray so that it overlaps the gingiva, treatments clean and debride the gums as well as provide maintenance level whitening. Thus, bringing returning to its periodontal roots

    15% Treatments: 2 daily, 45-60 minutes Common Use: Conservative Whitening These days, 15% has been left in the middle but may still have a place in your practice. This could be the right choice for a patient who who you believe will not follow dosage instructions and may likely overfill the tray causing blanching.

    20% Treatments: 2 daily, 30 minutes Common Use: Fast Whitening Whitens fast, but requires longer treatment times and more days than 30%. Trim the trays at the gingival margins and 20% is a good choice for patients that want fast results but may have some trouble following dosage instructions.

    30% Treatments: 2 daily, 20-30 minutes Common Use: Fastest at-home whitening available Trim the tray at the gingival margins with short treatment times (20-30 minutes) and 30% provides the fastest at-home results. Keeps the patients involved, engaged and motivated--maximum patient compliance.