Tooth Whitening Products: The Longer They Linger, the Better

The Product	The Cost	The Method	The Pros	The Cons
Pre-brush rinse	rinse About $6 per 16-oz. bottle	Swish the peroxide-containing liquid in your mouth for 60 seconds twice daily, then brush your teeth. Listerine¿s Whitening Pre-Brush Rinse foams impressive; manufacturer Pfizer cites the foaming action as evidence the rinse is laundering stains.	Cheap and easy, if you¿re going to use mouthwash anyway. Good for people who don¿t want to put a lot of effort into whitening; after 12 weeks of use, according to Pfizer¿s unpublished research, users experienced a lightening of tooth color.	A minute¿s not long enough for the peroxide to do much, say experts Gerald Kugel and Robert Gerlach; the brushing afterward is more likely than the rinse to whiten. Kugel says many users report sensitive teeth after use.
Whitening toothpaste	Usually about the same as regular, non-whitening formulations: a few bucks a tube	Whitening toothpastes often contain peroxide, but it¿s the silica and other abrasives that scrub away at the superficial stains and tartar.	You¿re brushing your teeth anyway, so why not choose a whitening formula? Gerlach notes that these products can help keep new stains from forming.	None, as long as your expectations aren¿t too high. Make sure whichever of the many available varieties you choose has fluoride to protect against decay and keep sensitivity at bay.
Strips, Paint-on Gels, and Over-the-Counter Tray-and-Gel Systems	Crest Whitestrips: $25 for 7-day treatment; Colgate Simply White Clear Whitening Gel, 14-day treat- ment, $6.99; Rembrandt Whiten- ing Pen, $12.99; Rembrant 2-hour White Kit (with tray) $19.99	Whitestrips are flexible strips you stick on your teeth for 30 minutes twice a day. Paint-on products are designed for day or night use; some are to be brushed away, others left to dissipate. Tray-and-gel systems provide mouth-guard-like trays to be filled with gel and placed on your teeth, usually overnight.	All three methods should, if used impec- cably, make teeth whiter. You can use them when you feel like it, without much advance planning beyond a trip to CVS.	Some people find Whitestrips hard to place and keep there. Gels can be tough to paint on, and can get diluted and wash away. Trays often fit badly, allowing saliva to seep in and solution to seep out, diluting the solution and making gums, tongue and lips sore.
Dentist-administered tray-and-gel treatment	Usually $200 to $350; as high as $700	After creating a custom set of plastic trays for you, the dentist fills them with high-concentration peroxide solution, fits them onto upper and lower rows of teeth, and lets you gel for 20 minutes or so. (Nearly all dentists offer a checkup and cleaning first, then send patients home with trays and solution for booster treatments.)	There¿s no dispute: This method really works. And, once you¿ve hauled yourself to the dentist¿s office, it requires almost no effort.	You have to plan ahead: You¿ll need two one-hour appointments, one to create a mold to cast the custom tray, another to do the bleaching.
Dentist-office whitening with or without light enhancement	Usually $500 to $600; range from $350 to $1,000	The dentist paints your teeth with a high- concentration peroxide gel, being careful not to get any on gums or lips. Often a special light is used to ¿activate¿ the gel.	This process can work as well as or better than a tray-and-gel treatment, making your teeth noticeably whiter right away. Usually only a single one-hour visit is required.	The jury¿s out on whether the light makes any difference; most experts don¿t think it helps, and some worry that the heat it generates might dehydrate teeth and damage enamel.
Veneers	$1,000 to $2,000 per tooth	A dentist creates thin porcelain sheets in the shade you both agree is appropriate, then affixes them permanently to your teeth.	Veneers can be the last good option for folks whose teeth don¿t respond to other whitening procedures. They can also be crafted to improve tooth shape.	Veneers require at least two visits to the dentist, and they are very expensive. And, Gerlach explains, veneers are forever: The process of adhering them to teeth alters the underlying surface in irreversible and unattractive ways.

The Washington Post Reported by Jennifer Huget