Several months ago I posed a question concerning the confusing (and potentially misleading) statistics placed on toothpastes, which my paranoid mind attributes to advertising spin and possibly outright lies by toothpaste makers. Wanting to get the most fluoride bang for my buck, I trusted only your answer, because I know firsthand just how expensive it is to maintain (and replace) one's teeth. I consistently check your column and understand that not all questions are answered, and that some questions are follow-ups on previous material. But today I see a brand-new article on coprophagia, of all things. I am hoping that a serious question didn't fall on ears deaf to all but the sensational or shocking. --Johnny Henson, via e-mail
Patience, chief. We get to everything (of consequence) eventually. Besides, after a column on coprophagia, what could be more fitting than one on the best way to clean your teeth?
Your original letter made a number of observations: (1) The price range for toothpaste is surprisingly wide. Sure enough, during a recent casual survey at the supermarket I noticed that the price per ounce ranged from 17 cents for Ultra Brite on sale to $3.00 for Rembrandt Plus "premium whitening toothpaste with fluoride." (2) Most toothpastes contain pretty much the same proportions of the same active ingredients. (3) However, not all do. Presumably you refer to the fact that most toothpastes use sodium fluoride (NaF) for cavity control while some use sodium monofluorophosphate (SMFP). A few also include ingredients to control gingivitis (inflamed gums) and tooth sensitivity, but, oddly, none lists an active ingredient to make teeth whiter, a common toothpaste claim. Your unsurprising questions: What gives, and which toothpaste is best?
Fluoride first. Over the past 30 years, most developed countries have reported declines in tooth decay in the neighborhood of 50 percent due to fluoride in toothpaste, drinking water, etc. Virtually all U.S. toothpastes contain a fluoride compound, either NaF or SMFP. In the early 1990s a few researchers claimed NaF was better at cavity control than SMFP, but the current scientific consensus is that they work equally well. The original decay fighter, stannous fluoride, introduced in Crest in 1955 (remember Fluoristan, fellow geezers?), is seldom used now--among other things it can stain teeth. Some recent studies, though, suggest it's useful in combating gingivitis.
Differences in the amount of fluoride used in various toothpastes are inconsequential. Although the percentages of NaF and SMFP vary, they provide roughly the same amount of fluoride--1,000 to 1,100 parts per million (ppm). In an era of maximum this and ultra that, such uniformity is curious, since (a) federal rules allow as much as 1,500 ppm in nonprescription toothpaste, provided the label says not to give it to kids under six; (b) research suggests 1,500 ppm toothpaste may be slightly (6 percent) better at controlling cavities than the 1,000 ppm kind; and (c) U.S. toothpaste makers sell high-fluoride toothpaste in Europe. The explanation, as far as I can tell, is that marketing a 1,500 ppm toothpaste here entails an expensive federal approval process not required of products in the lower range, and the one recent attempt (Extra-Strength Aim in the late 80s) wasn't conspicuously successful. But come on. Given the explosion of brand variations in recent years, is this the time for toothpaste hypesters to be telling themselves: Eh, what we've got is good enough?
You may now be concluding that all toothpastes are the same. Not so fast. What's confusing are federal labeling requirements. "Active ingredients" are those meant to confer a medical benefit. Others, such as whiteners, may be active in the colloquial sense but perform only a cosmetic function and so aren't singled out on the label. That said, the evidence that marquee ingredients other than fluoride accomplish anything is far from overwhelming. A rundown on some popular ones:
Whiteners. Research by manufacturers says they work; Consumer Reports among others says they don't, and that you should see your dentist about having your teeth bleached if they're discolored.
Desensitizing agents. Research on one common ingredient, potassium nitrate, is mixed at best--a 2001 review concluded it was ineffective.
Antigingivitis agents. Top-selling Colgate Total contains triclosan to reduce plaque and swelling and bleeding of the gums. Some studies report positive results, some don't, but the American Dental Association has given the stuff its seal of approval and Consumer Reports says it's good at germ busting. However, so are most other toothpastes.
Conclusions: (1) Notwithstanding your paranoia, most toothpastes aren't equally bad, they're equally good. When Consumer Reports rated 38 toothpastes in 1998, 30 were judged excellent. (2) Price mostly reflects the grandiosity of manufacturer claims, not product quality. Remember pricey Rembrandt? It got some of CR's worst ratings. Dirt cheap Ultra Brite, on the other hand, got some of the best.
Art accompanying story in printed newspaper (not available in this archive): illustration/Slug Signorino.