dental whitening revolution
TRANSCRIPT
-
7/28/2019 Dental Whitening Revolution
1/3
Dental Whitening Revolution
By Trisha OHehir,Hygienetown Magazine
It seems the number of whitening products increases daily. Consumer-whitening products
began with gels in trays and now include whitening strips, paint-on products, and felt-tip applicatorswith whitening substances. In fact, in a recent e-mail survey of dental hygienists conducted by
Hygienetown, nearly all respondents (95%) recommended home-use whitening to patients and 70%
said oral hygiene products were sold in their offices. The market is growing, the products are selling
and the number of choices keeps increasing.
With all of the attention to tooth whitening today, it seems odd to think that it wasnt too
long ago dentists discouraged their patients from wanting white teeth, saying: Teeth are shades
from yellow to gray; Pure white teeth arent natural; Really white teeth are probably dentures.
With no solution being offered by the dental profession, consumers decided to take matters into
their own hands, using Ajax or Comet cleanser to whiten their teeth.
When professional whitening products first entered the market, dentists were reluctant to
offer the procedure because it was considered cosmetic rather than therapeutic and thereforewas unprofessional. The perception of tooth whitening changed with the publics desire for whiter
teeth.
For some, their first experience with whitening is done to lighten an endodontically treated
tooth that has darkened. The tooth is opened up from the lingual, a cotton pellet soaked with
hydrogen peroxide is placed inside, and a photo flood light is used to speed the bleaching process.
The high concentration of peroxide used destroys the interdental papilla in the process, even with
the use of a rubber dam. From those crude beginnings, bleachinghas evolved into whiteningand
with it has come a revolution of change.
How does whitening work?
Just as peroxide products lift color from hair, peroxide whitening products lift stain from
tooth surfaces. Hydrogen peroxide is a combination of hydrogen and oxygen. There is an extra
oxygen molecule that hunts for another molecule to attach to, in this case molecules of color within
the enamel. The oxidation reaction breaks down the color trapped in the enamel surface into smaller
particles that are released from the enamel.
Carbamide peroxide is a combination of hydrogen peroxide and urea. Adding urea to
hydrogen peroxide stabilizes the formulation, produces a longer shelf life and improves taste.
According to the research, both products whiten comparably, since the whitening is achieved by
hydrogen peroxide in both cases.
Although the concentration for hydrogen peroxide products appear to be lower thancarbamide peroxide products, carbamide peroxide consists of one-third hydrogen peroxide and two-
thirds urea. Therefore, a 10% carbamide peroxide product contains only 3% hydrogen peroxide and
7% urea. From the other side, a 9% hydrogen peroxide product is equivalent to 27% carbamide
peroxide.
Whitening is achieved with a time/concentration approach. The shorter the time, the higher
the concentration needed. The higher the concentration, the shorter the time needed. In-office
products generally use peroxide at concentrations of 20-35% for short periods of time. At-home
products are generally lower concentrations used over a longer time period.
Most in-office whitening is not sufficient to achieve the desired results in a single visit.
According to a study reported in the February 2006 issue of Quintessence International, one to four
visits are needed to achieve patient satisfaction with whitening results. Home-use products areprovided to supplement and extend the in-office results and for touch-ups later. The primary
advantage of in-office procedures is time. However, according to research published by Dr. Van
-
7/28/2019 Dental Whitening Revolution
2/3
Haywood of the Medical College of Georgia, whitening achieved with a lower concentration over a
longer period of time is more stable than that achieved with a high concentration applied for a short
time.
Even tetracycline staining can be altered with whitening over an extended period of time, or
deep bleaching. Researchers have shown significant effects when the home-use whitening process
is extended to six months or more. Other clinicians have found that preconditioning the teeth with
several weeks of home-use whitening followed with a high concentration, in-office treatmenteffectively lightens tetracycline staining and/or fluorosis. According to Dr. Marshall White, the
slow preconditioning of enamel with home-use whitening makes the enamel surface more receptive
to greater color change later using a higher concentration, in-office procedure.
Teeth can be lightened from one to several shades. Patients should be prepared for some
rebound as whitening procedures often dehydrate the enamel, leaving it lighter than it will be when
again saturated with saliva. Explaining this to patients will prevent disappointment later.
According to research, the lights and lasers provide very little, if any, advantage over the
whitening products used alone. The heat from the light will speed the effect of the peroxide and also
will dehydrate tooth surfaces. More recently, whitening products have incorporated photo-activating
substances to enhance the effect of the light or laser. The lights and lasers provide a psychological
stimulus that patients find trendy and therefore desirable.Pain or sensitivity associated with whitening procedures is generally transient, lasts no more
than 24 hours and can be alleviated with ibuprofen. Recommending the lowest concentrations of
peroxide will help in minimizing sensitivity. Still, the best approach is to prevent pain and
sensitivity by recognizing problems prior to whitening. Ill fitting trays and overfilling trays with
whitening gel can irritate and sting gingival tissues. Floss cuts and tissue abrasions are prime targets
for peroxide irritation. A jolt or shock, often called a zinger, to a single tooth may be due to direct
access of the peroxide to the dentin, due to cracked or chipped teeth or leaking margins on
restorations.
In addition, some manufacturers are adding sodium fluoride and potassium nitrate to
whitening products to control sensitivity. Furthermore, some clinicians have their patients use a
fluoride, sensitivity toothpaste or a remineralizing product for a couple of weeks prior to whitening.
Others have patients use one of these products in the bleaching trays for 30 minutes before
whitening or just after. Several new products and whitening formulations have been introduced
recently to address the problem of sensitivity. Products containing amorphous calcium phosphate
(ACP) not only reduce sensitivity, they also have been shown in laboratory studies to reduce
susceptibility to enamel caries. Whitening doesnt have to be painful when effective preventive
measures are taken.
Conclusion
The whitening revolution is here to stay. Products are improving and more options areavailable now than ever before. It is the professionals duty to inform patients about the proper
choices emphasizing potential problems and helping them to make the right choice before they
decide to start the teeth whitening procedures, be this at home or in the surgery.
The patient itself should on the other hand understand the responsibility attached to his or
her choice of beginning and, more importantly, continuing the procedures at all times, irrespective
of any alterations in lifestyle and to maintaining a close relationship with the dental hygienist, who
should be consulted as often as problems occur or the patient intends to undergo changes in
products.
Whitening should not, therefore, be opted for only on aesthetic grounds but on a careful
assessment which requires the dental professional the evaluation of the patients general health,
dental status as well as social status. Many patients presenting a serious psychological problemsmay require the dentist or hygienist the onset of such procedures without taking into account his/her
own ability to continue treatment.
-
7/28/2019 Dental Whitening Revolution
3/3