Do you still have questions about sensitivity using At-Home 30%? Does At-Home 30% truly belong in the mainstream of professional whitening or in the mainstream of your practice? Top clinicians have dug into the subject and have resoundingly positive answers.

Michael Miller, D.D.S., co-founder of Reality Publishing Co. and editorial board member of Practical Periodontics and Aesthetic Dentistry, had his doubts about 30% for at-home use. At a conference last winter, Dr. Miller had this to say, "When I first thought of somebody doing home bleaching with a 30% carbamide peroxide I said, ‘You’re out of your mind.’ This’ll never work, it’ll blow out teeth, they’ll be sensitive, it’ll be this, it’ll do that. Well I can tell you, it doesn’t do that. And, what’s very nice about this product is that you can have patients wear the tray twice a day for 20 minutes and you can go from a C3 to a C1 in one week " in one week, 20 minutes a day - driving to and from work. So this 30% carbamide peroxide, as long as they keep the wear time down to a minimum and you don’t cover any of the gums, so you scallop the trays very nicely, I am firmly convinced that this is the way that home bleaching is going to go."

Dr. Bill Strupp, D.D.S., a world-class clinician with thirty-one years of experience and the publisher of "Crown & Bridge Update" had his questions, at first. He ran his own study to compare patient experiences - one group using 15% and one using 30%. Dr. Strupp explains, "To my surprise and delight, the patients who whitened their teeth with the 30% c.p. gel were very compliant due to the immediate gratification they experienced from seeing their teeth whiten so rapidly. More importantly, the patients who chose the 30% carbamide peroxide gel did not report any incidence of acute pulpal sensitivity over my patients for whom I prescribed the 15% c.p."

Dr. Strupp went on to say, "Some people wear any percentage 20-60 minutes, find it is too sensitive and they take it out. These are people who have open dentinal tubules, fillings that are leaking, root surfaces that are exposed, decay, or other serious problems present. You have to have a root surface exposed, or a filling exposed, or an incisal edge with the dentin showing through in order for there to be sensitivity. Just plain old virgin teeth with enamel on them typically do not get sensitive." Dr. Strupp now whitens all of his patients with the At-Home 30%.

Robert Drosman, D.D.S., conducted a 1,400-patient clinical evaluation and statistically verified less than a 5% acute pulpal sensitivity rate. This is equivalent to only one out of 20 patients. Dr. Drosman’s 1,400 patient study has proven that at-home 30% using short-term modality is safe and effective for at-home use.

Rodney Ogrin, D.D.S., has been a pioneer of whitening for more than 11 years and is a believer in using high concentrations/low treatment times to overcome sensitivity. Dr. Ogrin was the first to introduce 15%, 20%, and 30% carbamide peroxide strengths for at-home use. He describes his experience with 30% and sensitivity, "Since the introduction of 30%, literally thousands of patients have used it to whiten their teeth without pulpal sensitivity. Soft tissue irritation is virtually a moot point when the tray is scalloped properly and when the patient follows a few simple dosage instructions."

To best help patients have the most comfortable and effective tooth whitening experience, it is helpful to keep in mind all the different types of tooth sensitivity and their symptoms, causes, and solutions. Here is a review:

1. Exposed Dentin
Cause: Exposed dentin is one of the main culprits of sensitivity. The dentinal tubules are able to transmit messages of cold, hot, or pressure to the pulp of the tooth. Dentin can be- come exposed for several reasons: over-aggressive brushing, receding gums, enamel erosion from acidic foods, or enamel fractures. A leaking margin is a gap between the enamel and composite material and can also cause pulpal sensitivity.
Symptom: A jolt or shock in a single tooth.
Solution: Replace or seal any leaking restorations before bleaching. Individuals with a history of sensitivity from exposed dentin should use a KNO3/Fluoride toothpaste two weeks prior to and during treatment.

2. Dehydration
Cause: Tooth dehydration occurs when bleaching trays are worn for extended periods of time.
Symptom: A dull toothache or headache.
Solution: Short-term modality allows rapid saliva re-hydration to quickly counteract the hydrostatic imbalance created by the H2O2 in the dentinal tubules and enzyme systems in the pulp. Keep treatment times short (20-30 minutes). If a patient becomes sensitive due to over wearing the trays, suspend treatment for at least 24 hours or until the sensitivity subsides.

3. Heat
Cause: Heat from a light source whether it be lasers, plasma arc lights, or curing lights has the potential to cause sensitivity.
Post-op sensitivity has been reported by as many as 94% of patients who used a laser or light activated system.1 Pulpal damage can occur when in-office procedures combine heat and H2O2. The hydrodynamic pressures of a H2O2 exposed pulp under heat can disrupt the metabolic pathway or damage biological membrane.
Symptom: Inflammatory response that may result in pulpal necrosis and the need for future endodontic treatment.2
Solution: Do not use a light source to whiten teeth. Heat only accelerates the whitening process by a few minutes. Not enough time is saved to warrant pulpal damage. As explained by the notable clinician Bill Strupp D.D.S., “The heat can definitely create problems. It makes no sense to me to subject a patient to that kind of risk when we can achieve such startlingly fast and predictable results with the 30% at-home whitener.” Reality’s Michael Miller, D.D.S. further explains, “Our studies, both in vitro and in vivo, as well as independent studies conducted elsewhere, show that there is no advantage to using any of these curing-type lights for bleaching.”

1. Clinical Research Associates, “Tooth Bleaching, State-Of-Art.” CRA Newsletter, April 1997, Vol.21, Issue 4, p. 2.

2. Bowles WH, Thompson LR, Vital bleaching: the effect of heat and hydrogen peroxide on pulpal enzymes. Journal of Endodontics 1986;12:108-12.