PATTI NEIGHMOND, BYLINE: And I'm Patti Neighmond in Los Angeles. One of the best things you can do to prevent tooth decay is brush your teeth well and floss every day. But choosing a toothpaste can be overwhelming.
LARRY KOZEK: Toothpaste, look at that.
NEIGHMOND: I'm standing in a local pharmacy with my dentist Dr. Larry Kozek. We're looking at rows and rows of toothpaste.
KOZEK: I remember when toothpaste used to be toothpaste.
NEIGHMOND: What do you mean?
KOZEK: Well, it was white, it tasted like peppermint. Now we have a whole menu of items in there. We're afraid not to put things in toothpaste. We're afraid it won't sell if it doesn't have everything in it.
NEIGHMOND: Well, exactly, 'cause what are we looking at? Truly radiant, sensitive, daily repair, advanced whitening.
KOZEK: Pro-health, my goodness - radiant white.
NEIGHMOND: But does all this do anything or is it hype to sell the product?
KOZEK: Let's see, can we read some of these ingredients?
KOZEK: Water, zorbitrol, hydrated silica, poloxamer 407.
NEIGHMOND: Moisturizers, flavorings, coloring. But Kozek says the single most important ingredient is fluoride.
KOZEK: Because fluoride is the ingredient that hardens the enamel and makes the tooth more resistant to the acids of the bacteria in the mouth.
NEIGHMOND: And there are different types of fluoride.
KOZEK: Sodium fluoride and stannous fluoride. And it's pretty well accepted that the stannous fluoride is more effective. So if I were looking for a toothpaste and wanted the basic protection and basic care, I would look for a toothpaste that had stannous fluoride in it.
NEIGHMOND: When you were reading that list of ingredients, was that among them?
KOZEK: I didn't see that in any of those (laughter).
NEIGHMOND: So let's see if we can grab another one and see if it has stannous fluoride in it.
KOZEK: OK, well, let's take this here.
NEIGHMOND: This one didn't contain it either. Another important ingredient, he says, triclosan to fight bacteria that causes tartar. Some worry this chemical is contributing to antibiotic resistance. And if you have sensitive teeth, desensitizing toothpaste does work.
And the whiteners, do they work?
KOZEK: Everybody likes to have white teeth. And we find that the whiteners that are added to the toothpaste and to the mouthwash over time tend to be able to help people keep their teeth whiter but strictly a cosmetic.
NEIGHMOND: And, of course, floss.
KOZEK: The singularly - the most important feature of cleaning our teeth. Which works better, waxed dental floss, plain dental floss, glide dental floss? As long as we mechanically are able to use this string to dislodge the film of plaque on the teeth, we're doing an effective job.
NEIGHMOND: Kozek recommends flossing first, followed by brushing. Patti Neighmond, NPR News. Transcript provided by NPR, Copyright NPR.