The Simple Truth and Formula for Whitening Your Teeth

Are light-activated bleaching techniques such as BriteSmile and Zoom, marketed as the best science has to offer in the science of teeth whitening any more effective than less expensive bleaching gels or over-the-counter white strips? In other words, is the exorbitant price you pay - up to $500 - for the light worth it?

The Center for Dental Health (CDH) in Washington, D.C., does not find light-activated bleachings techniques necessary. They offer a system of preloaded whitening trays made by Ultradent Products. The tray adheres to the teeth and is worn for about 60 minutes per day until patients get the results they want. The CDH says the jury is still out on whether light is a more effective whitener; some studies suggest that the light does not enhance the results of bleaching. They found the "lights don't generate enough heat or give off enough UV light to accelerate the chemical reaction."

Professional teeth whitening systems use 25 percent hydrogen peroxide. Approximately seven days later, however; after your teeth rehydrate, that awful color may come back and that's why extra gel is recommended to keep in stock so that the consumer can can apply it themselves.

There is evidence that in-office light bleaching may enhance the process, however; the difference is so small and not 100% conclusive that it hardly compensates for the extra money spent.

Whether a patient chooses chair-side bleaching by a dentist, take-home trays or over-the-counter whitening strips, the mechanism of action is the same, he says. The only difference is how long it takes to get the effect. The stronger the concentrations of hydrogen peroxide in the product, the faster the effect. -- Joe Ontiveros, researcher and a dentist with the University of Texas.

Ontiveros still recommends home bleaching trays to his patients first, "because it's got a long track record and it's very predictable."

Overall, there's a simple formula for whitening that smile. Try a high concentration of peroxide and if you want to go all out use Crest Whitestrips.

Remember four out of five dentists recommend Trident Spearmint gum, but what they don't tell you is that it is based only on five dentists who gave the right answers.

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Child Dies From a Toothache...No Insurance.

In a wealthy country like ours no child should ever die from a toothache. Our government literally throws billions of dollars at Iraq without blinking an eye, and then cannot account for any of it, yet 45 million people in the United States do not have health insurance and cannot afford the most basic health care. I wonder how many people those billions of dollars unaccounted for, much of it in cash, could have covered?

Some poor children have no dental coverage at all. Others travel three hours to find a dentist willing to take Medicaid patients and accept the incumbent paperwork. And some, including Deamonte's brother, get in for a tooth cleaning but have trouble securing an oral surgeon to fix deeper problems.

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Bullet Proof Teeth?

Fibers used in bullet-proof vests quadruple toughness of dental composites

Fiber-reinforced composites are so strong that dental bridges made with them can be attached with less invasive techniques to adjacent teeth.

Vistasp Karbhari, a professor of structural engineering at UC San Diego, has developed fiber-reinforced polymer composites as strong, lightweight materials for aerospace, automotive, civil and marine applications, so he thought, “If they work so well in highway bridges, why not dental bridges"”

In a paper scheduled for publication in Dental Materials, Karbhari and Howard Strassler, a professor and director of Operative Dentistry at the University of Maryland Dental School, report the results of detailed engineering tests on dental composites containing glass fibers as well as the type of polyethylene fibers used in bullet-proof vests.

Karbhari and Strassler found that the toughness of fiber-reinforced dental materials depends on the type and orientation of the fiber used. Their report, available at the Dental Materials website, shows that braided polyethylene fibers performed the best, boosting toughness by up to 433 percent compared to the composite alone.

Many of the strength and durability tests reported in the paper are not currently required by the U.S. Food and Drug Administration (FDA), which regulates dental composites as class II prescription devices. The agency requires eight minimum tests plus biocompatibility tests to ensure that dental composites are safe and nontoxic.

“Fiber-reinforced composites are now widely used in the aerospace and automotive industries and the experience we’ve gained in these applications can be applied in a more rigorous way in dentistry and medicine to tailor performance to exacting requirements,” said Karbhari. Dentists began using particle filled composites 10 years ago as an alternative to ceramics and mercury-containing metal amalgams. Strassler selected three commercially available fiber-reinforced composites for analysis.

Howard Strassler, a professor and director of Operative Dentistry at the University of Maryland Dental School, said makers of fiber-reinforced dental composites need a much better understanding of how their...

Dental composites made with glass or polyethylene fibers are sold as pliable ribbons that dentists mold into the required shape and then harden with curing lights. “Many reinforcing fibers can add strength and toughness to dental composites,” Karbhari said, “but if they are improperly aligned they could actually accelerate damage to existing teeth.”

“What’s been missing until now is a rigorous, reproducible way to test the durability and resistance to breakage for these materials,” Strassler said. “Makers of fiber-reinforced dental composites need a much better understanding of how their products actually perform as part of a restoration, crown, or bridge, and this study provides an analytical standard with which all composites should be evaluated in the future.”

The three products tested were a 3-millimeter-wide ribbon of unidirectional glass fibers, a 3-millimeter-wide ribbon of polyethylene fibers woven in a figure-8 stop-stitch leno-weave, and a 4-millimeter wide ribbon of polyethylene fibers woven in a biaxial braid. The resistance to breakage and various measures of toughness of the three preparations were compared to the dental composite alone.

“All three fiber fabrics dramatically increased the durability and strength of the dental composite, but the polyethylene fibers braided in a biaxial ribbon performed best,” said Karbhari. “The tests required by the FDA indicate that fiber-reinforced composites are safe, but those tests are only partially informative. Our analyses show that we can optimize these materials to match and improve performance of teeth, for greater durability, toughness, and resistance to breakage.”

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