There are many different types of toothpaste on the market that are used to reduce tartar, prevent cavities, and improve gum health. Around 90 percent of these contain fluoride, a mineral found in relatively low concentrations in fresh and seawater. Depending on where you live, the water supply may also be fluoridated to reduce the risk of cavities, especially in kids.

Fluoride toothpaste by far provides a higher concentration of the mineral than any other source. Fluoride's effectiveness in promoting dental health has been long established and is considered by the Centers for Disease Control and Prevention to be "one of 10 great public health achievements of the 20th century."

Despite this, there is ongoing debate as to whether fluoride can cause harm in some groups, particularly children. Detractors have even suggested that long-term exposure may weaken the bones and even increase the risk of certain cancers.

There are many different types of toothpaste on the market that are used to reduce tartar, prevent cavities, and improve gum health. Around 90 percent of these contain fluoride, a mineral found in relatively low concentrations in fresh and seawater. Depending on where you live, the water supply may also be fluoridated to reduce the risk of cavities, especially in kids.

Fluoride toothpaste by far provides a higher concentration of the mineral than any other source. Fluoride's effectiveness in promoting dental health has been long established and is considered by the Centers for Disease Control and Prevention to be "one of 10 great public health achievements of the 20th century."

Despite this, there is ongoing debate as to whether fluoride can cause harm in some groups, particularly children. Detractors have even suggested that long-term exposure may weaken the bones and even increase the risk of certain cancers.

Benefits

Prior to the 1950s, toothpaste didn't hold much promise for oral health. It was only in 1952 that scientists with the Proctor & Gamble corporation began conducting clinical trials of a fluoride-enhanced toothpaste involving 1,500 children and 100 adults. Four years later, the first fluoride toothpaste, known as Crest, was released.

What the scientists found (and future research confirmed) was that fluoride helps prevents cavities in three key ways:

1. Fluoride "remineralizes" tooth enamel by bonding to areas of decay and attracting other minerals, like calcium, to the site of the damage.
2. Fluoride prevents further decay by stimulating the production of fluorapatite, a type of tooth enamel that is highly resistant to acids and bacteria.
3. Fluoride exerts antibacterial properties that not only inhibit the growth of bacteria but prevent the microbes from sticking to teeth.

Fluoride cannot reverse cavities that have already been established but can slow the rate at which they develop. This is why twice-daily brushing is recommended by most dentists. The more constant the exposure to fluoride, both in toothpaste and the water supply, the greater the cavity prevention.

Safety

Despite the many benefits of fluoride toothpaste, it does have its limitations. If used inappropriately, fluoride toothpaste may cause injury to developing teeth.

The condition, called dental fluorosis, occurs during childhood when the teeth are still coming in. During this time, the excessive exposure to fluoride can cause the depletion of minerals (called hypomineralization) in the tooth enamel. This can cause whitish opaque patches on the surface of the teeth.

If left unchecked, dental fluorosis can lead to irregularities on the tooth's surface (including ridges, pits, and indentations), some of which may carry over into adulthood. Despite the clear link between fluoride and fluoridosis in kids, scientists have yet to identify the exact mechanism that triggers hypomineralization.

Fluorosis occurs most commonly in children six and under, with those under two years being at greatest risk.

From the age of seven onward, most of a child's permanent teeth will have grown in and completed development, reducing the risk of fluoridosis.

Brushing with fluoride is only one of the ways that dental fluorosis can develop in children. Swallowing fluoride mouthwash or toothpaste residue are common culprits, as is drinking water with high concentrations of fluoride.

Despite claims to the contrary, exposure to fluoride during pregnancy does not increase the risk of dental fluorosis in children.

Fluoride-Free Toothpaste

Fluoride-free toothpaste has gained popularity among consumers who are either attracted to "natural" products or who would rather avoid fluoride for whatever reason. Some contain baking soda or other ingredients that are believed to exert antimicrobial effects.

Proponents of fluoride-free toothpaste contend that by avoiding sugar and brushing regularly to remove plaque, your need for fluoride is all but eliminated.

The problem with this argument is that sugars are present in many of the foods we eat, including dairy products, fruits, and vegetables. Moreover, cleaning your teeth regularly doesn't alter the mechanisms that trigger tooth decay, including the demineralization of tooth enamel which goes largely unseen.

While non-fluoride toothpaste can keep your breath fresh and give you a bright, shiny smile, they are far less likely to prevent enamel erosion, gingivitis, and the buildup of calculus (tartar).

It is for these reasons that fluoride toothpaste brands are given the ADA's Seal of Acceptance, while fluoride-free toothpaste brands are not.