[Effie_drine]

Getting the pearly whites you've always wanted is becoming easier, thanks to recent advances in tooth-whitening technology. But selecting the best at-home bleaching system may depend more on your needs than the price tag.

New research shows that professional tooth-whitening strips available from your dentist can produce better whitening results than more expensive systems that use custom-made trays.

Both tooth-whitening systems tested contained higher concentrations of peroxide than are available in over-the-counter products, but researchers say the results may also apply to some nonprescription products.

"The important factor seems to be a combination of the concentration and the time in contact with the tooth surface," says researcher Ingvar Magnusson, DDS, PhD, a professor of oral biology at the University of Florida.

That means picking the right product for you may depend on personal preference as well as how much time and money you want to spend.

I think they are all about equally easy to use," says Magnusson. "For some, it might be difficult to remember to put a strip on for half an hour twice a day, and for some people it may be easier to put a tray on when they go to bed at night."

"But the trays have to be custom made in a dental office, which means there's a big price difference," Magnusson tells WebMD.

Researchers presented the results of two separate studies on the products last week at the annual meeting of the International Association of Dental Research in Honolulu. The research was funded by Procter & Gamble, a WebMD sponsor.

Rating the Whiteners

In the studies, researchers compared the safety and effectiveness of a strip-based 14% hydrogen peroxide gel product (Crest Whitestrips Supreme) with customized tray whitening systems using a 16% and 20% carbamide peroxide gel (Nite White Exel).

The participants wore the strips on their upper front teeth twice a day for 30 minutes for three weeks. Tray users wore the customized trays with the whitening solution overnight for nine days to two weeks.

The studies showed that the strips whitened teeth better and with fewer side effects than the trays.

Using digital imaging to measure color changes in the teeth before and after the treatments, researchers found those who used the strips experienced a 91% improvement in yellowness reduction compared with those who used the trays containing 16% carbamide peroxide.

Researchers also found that use of the strips over 21 days produced much less tooth sensitivity and gum irritation than use of the trays with 20% peroxide gel for 14 nights.

Picking the Right Tooth Whitener

Similar tooth-whitening strips and tray systems are available over the counter, but they contain lower concentrations of peroxide than the ones used in the studies. That means it will take longer to produce results, and the whitening effects may not be as dramatic.

Although tooth-whitening strips may be less expensive that custom-made tray systems, Mike Malone, DDS, president of the American Academy of Cosmetic Dentistry, says there's also another important consideration that was not addressed by these studies.

"The biggest difference between strip bleaching and tray bleaching is the number of teeth affected," says Malone. "Strips that are presently available are only long enough to cover 6-8 teeth."

"Someone with a fairly wide smile will find that their front teeth are white, but the other teeth that show on the sides will not be affected," Malone tells WebMD.

Malone says at-home teeth whitening is not recommended for people with porcelain crowns, bonding, or other tooth restorations. Peroxide-based bleaches will only bleach natural teeth and will not whiten caps, crowns, veneers, or filings.

In addition, people that need whitening of discolored teeth -- such as teeth stained gray from the use of tetracycline -- won't experience good results with home teeth whiteners.

Malone says he expects to continue to see improvements in tooth whitening technologies available at the dentist's office and for home use.

"I think we are going to see the materials work a little faster and probably become a little more comfortable," says Malone.

By Jennifer Warner

[Effie_drine]

I love white teeth the crest stripes really seem to work well for me.

[Annabelle]

Thank's Effie I drink alot of coffee. So I can use all the help I can get. I've also noticed that the price of the strips has decreased from the first time I looked at them.