Tooth Whitening Without Sensitization

Antiaging is more than fighting gray hair, wrinkles and age spots; it also includes maintaining skin health, a fit physique and a bright, white smile. Many of these effects can take months to achieve with an artillery of products and a gym; however, white teeth can be achieved in just a few hours.

Teeth whiteners are available as OTC strips and gels, but consumers seeking more immediate and dramatic effects often visit the dentist for an in-office procedure or take-home solution. In any case, many of these treatments increase tooth sensitivity and damage the gums, according to Raymond Frye, DMD, a cosmetic dentist and owner of Bling Dental. Therefore, he developed a whitening solution based on a combination of carbamide peroxide with a desensitizer.

Whitening Challenges
As a dentist, Frye has observed patient reactions to in-office whitening procedures, noting the sensitivity they experienced. According to Frye, the in-office procedure is effective but is activated by light, which can be damaging to nerves in teeth. “The light is so fast and powerful that the nerve does not have a chance to respond with pain to alert the consumer that damage is occurring,” said Frye.

“The light gets very hot and it is overheating the tooth. [Also], the actives used do not need to be activated by light, so the light is unnecessary to the process.”

According to Frye, in-office systems, OTC strips and take-home gels cause tooth sensitization since the whitening agents used, typically hydrogen peroxide and carbamide peroxide, dry out the teeth. He likened this effect to hair dyes, which employ similar bleaching agents and cause similar drying effects on hair.

“Both in-office and at-home whitening products dehydrate the teeth, and because [the teeth] are not exposed to saliva, which keeps them hydrated, this leads to sensitivity.” Frye added that most at-home whitening products such as strips used over a two-week period are effective but the teeth still become sensitive.

Frye notes that in addition to tooth sensitivity, gum damage can occur from whitening treatments. “A user must be sure they are not getting the whitening material on their gums,” said Frye, who added that strips do not protect the gums from the whitening materials.

A Non-sensitizing Solution
The at-home whitening product that Frye developed, Icing 30 Carat, is said to eliminate tooth sensitivity as well as damage to gums and teeth. While the formulation contains 30% carbamide peroxide, the highest percentage allowed in OTC products, the material acts quickly and thus remains on the teeth for a shorter period of time.

“Effective in-office procedures use 35% of either carbamide peroxide or hydrogen peroxide,” explained Frye, who noted this is only 5% higher than the at-home version he has developed. Most at-home tooth whiteners, according to Frye, are formulated with 12–16% whitening agents, making them effective but over longer periods of time. “The higher the percentage of whitening agent, the less time you have to wear the product, resulting in less sensitivity.”

To further decrease the sensitivity of teeth, potassium nitrate was added to the whitening gel. Frye explained, “Teeth are porous, and potassium nitrate fills the pores or tubules in the teeth that are dried out from the carbamide peroxide.” According to Frye, when these tubules are filled, the teeth are less sensitive.

Sensitivity also was the reason Frye chose to use carbamide peroxide rather than hydrogen peroxide. “The two agents are comparable, but you might not be able to achieve the same level of desensitization with the hydrogen peroxide as you can with carbamide peroxide,” he said.

In addition to the whitening gel, the system includes a thick, tailored whitening tray that is molded to the consumer’s teeth to protect the gums. “We provide a rubberized tray that is heated in the microwave and manipulated by the customer’s tongue and fingers to mold it to their teeth,” said Frye.

Dental Outlook
From his dental practice, Frye not only gleaned tooth-whitening knowledge, he also used it to test the whitening system and collect feedback from patients. He plans to use this knowledge to develop future oral care products, including a whitening toothpaste.

“[Current] whitening toothpastes have the potential to cause sensitivity because they are abrasive,” said Frye, who explained that they remove the calcium- and fluoride-rich top layer from the tooth. Frye expects to utilize information gained from his practice to develop a non-abrasive product. However, he notes that only superficial staining can be removed via toothpaste, and that intrinsic staining must be bleached.

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