Dental health experts worry that more people are using toothpaste that skips the most important ingredient — fluoride — and leaves them at a greater risk of cavities.
Most brands of toothpaste contain fluoride. While health authorities recognize fluoride as a cavity blocker, the internet is dotted with claims, often from "natural" toothpaste marketers and alternative medicine advocates, that fluoride-free toothpaste also prevents cavities.
Dental authorities disagree.
"It's really important to debunk this idea that brushing your teeth stops decay. You need to have the fluoride," said Damien Walmsley, a scientific adviser to the British Dental Association and dentistry professor at the University of Birmingham.
That view was underscored this week by an article in the dental journal Gerodontology that reviewed the scientific literature on cavities. Its primary conclusion is that, without fluoride, oral hygiene efforts have "no impact" on cavity rates.
Dentists generally recommend fluoride for cavity fighting, but some believe that the mechanics of wiping your teeth clean of plaque also reduces cavities.
In the review, University of Washington researchers looked for high-quality studies since 1950 and found just three. Carried out in the U.S. and Great Britain and published from 1977 to 1981, they involved a total of 743 children, ages 10 to 13, who flossed and brushed regularly for up to three years.
When the studies were evaluated statistically as a whole, there was no significant cavity reduction from simply brushing or flossing without fluoride.
"What it says to me is that the toothbrush is just a delivery system," said Richard Niederman, a dentist and professor at New York University who saw an advance copy of the study and found the findings credible.