Benefits and Safety of Fluoride Toothpaste

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.

Types of Toothpaste

To achieve the benefits of fluoride use, a toothpaste must have a concentration of at least 1,000 parts per million (ppm). Most commercial brands contain between 1,350 ppm and 1,450 ppm, usually in the form of sodium fluoride or sodium monofluorophosphate.

High-fluoride toothpaste generally contains 1.1 percent (5,000 ppm) sodium fluoride and is typically used in adults with extensive tooth damage or medical conditions that place them at risk of cavities (including dentures, orthodontic devices, or dry mouth caused by disease, medications, or cancer therapy).

According to a 2016 multicenter study done in Europe, high-fluoride toothpaste increases the surface hardness of untreated tooth decay far better than regular fluoride toothpaste (1,300 ppm).

Yet another type of fluoride, known as stannous fluoride, is able to provide oral protection while reducing tooth hypersensitivity. Other brands add chemicals like strontium chloride or potassium nitrate to help alleviate tooth sensitivity.

Children's toothpaste is designed for toddlers and kids ages six and under and has a fluoride concentration of 1,000 ppm. Anything below 1,000 ppm is no longer recommended.

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.

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.

Controversies

Fluoride has been demonized by some who believe that supplementation of any sort can cause more harm than good. Much of the contention stems from the practice of water fluoridation, which some insist is unethical and non-beneficial.

What is known is that excessive levels of fluoride in the public water supply can lead to dental fluorosis and even skeletal fluorosis (characterized by the weakening of bones). In North America, situations like this are extremely rare and mainly associated with a mishap in the management of the municipal water supply.

From 1991 to 2010, four such occurrences were reported in the United States in which fluoride levels spiked from the 1.5 milligrams per liter (mg/L) recommended by the World Health Organization to levels as high as 220 mg/L. While transient increases like this may cause nausea, vomiting, and diarrhea, the long-term risks are considered minimal.

Many of the claims of potential harm are based on pseudoscience and conspiracy theories. This includes assertions that fluoride can cause bone cancer and osteosarcoma, the claims of which have been repeatedly debunked by scientists.

For its part, the ADA issued a statement declaring that fluoride toothpaste is not only integral to good oral health, but it should be used as soon as a baby's first tooth comes in.

Recommendations

In aligning itself with the ADA, the American Academy of Pediatrics (AAP) endorses the use of fluoride toothpaste at the emergence of a baby's first tooth. Furthermore, instead of fluoride-free or very low-fluoride toothpaste previously endorsed, both the ADA and AAP recommend the use of a children's toothpaste (1,000 ppm).

The proper use of fluoride toothpaste varies by the child's age:

• For children under three years old, brush with a "smear" of toothpaste. To minimize the risk of swallowing, angle the baby’s head slightly downward so that any extra toothpaste can dribble out of the mouth.
• For children age three to six, apply no more than a pea-sized amount of toothpaste to the brush. To reduce the risk of swallowing, encourage the child to spit out the residue rather than rinsing with water.

Even if the baby or child swallows the prescribed amount, the concentration of fluoride would unlikely cause any harm. If your child repeatedly swallows toothpaste, speak with your dentist who may be able to recommend a less "tasty" brand your child will be less likely to swallow.

As for adults, a high-fluoride toothpaste should not be used as your everyday brand unless you have a medical condition that places you at an increased risk of cavities or you wear complex, fixed braces for several months at a time.

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.