Going in the white direction

There are many methods for obtaining dazzling smile

— Cristina Byvik Martinez / Union-Tribune illustration


Finally, there are the various and rather dubious home remedies for whitening teeth:

Brushing with lemon juice.

Don't. Lemon juice can lighten the color of your teeth, but only at the expense of your teeth. The juice is acidic. It causes calcium loss. This whitens teeth because calcium gives teeth some of their off-white color. It also means affected teeth are less resistant to decay and cavities. Your teeth might be brighter, but you could have fewer of them.

Brushing with mashed-up strawberries.

Another ill-advised idea. The notion here is that the strawberries' fibrous pulp and seeds act as scrubbers, scraping away nasty plaque and germs. But the fruit's sugars and acids do more harm than good, requiring that you immediately and thoroughly brush with a fluoride toothpaste.

Brushing with baking soda.

This doesn't really whiten teeth — there's no bleaching action — but baking soda can help remove plaque and make teeth shiny because it's abrasive. Use too much baking soda too often, however, and you may damage the enamel of your teeth.

Brushing with wood ash.

Wood ash (presumably retrieved from your fireplace) does whiten teeth because it contains potassium hydroxide, otherwise known as lye. But the ash has to come from a hardwood, such as oak, maple or walnut. Ash from softwoods like pine don't contain enough potassium hydroxide to be effective.

Again, be careful. Wood ash may contain other chemicals and compounds you wouldn't want to put in your mouth. Also there's no way to know how much potassium hydroxide you're actually getting in a dab of wood ash; too much too often can significantly damage your teeth.

— Scott LaFee

Everyone loves a mouthful of pearly whites. Call it the thrill of the grill. But few of us, alas, are born with teeth white enough and bright enough to dazzle for a lifetime.

Some folks simply grin and bear it, mouths presumably closed; others take action.

Teeth whitening has become big business. It's the most requested dental procedure among patients age 40 to 60 in the United States. Last year, Americans spent more than $2 billion to whiten their teeth, $1.4 billion for over-the-counter kits and concoctions.

So, are we smiling more?

Well, that depends. Teeth whitening — or more precisely, bleaching — doesn't work well for everyone. As they say, results vary. The biggest determinant is the state of your teeth when you start. Yellowish teeth bleach better than brownish teeth, according to studies by the American Dental Association. Grayish teeth are least responsive.

Lots of things account for the color of your teeth. Natural color varies dramatically. Healthy teeth are typically slightly yellow, the color coming from dentin, a dense tissue beneath each tooth's outer layer of enamel. Healthy dentin is slightly yellow.

Age plays a role too, of course. Over time, the natural color of teeth intensifies and darkens — the result of things like wear and tear and accumulated stains.

A lifetime consuming liquids like coffee, tea, cola and wine can darken teeth, though these stains may also be among the easiest to remove. Frequent brushing with a whitening toothpaste is usually enough to minimize the problem. Acidic foods like citrus and vinegar contribute to enamel erosion, which makes the surface of teeth more transparent, revealing more of the underlying dentin.


