This So-Called New Toothpaste Has Been Around for Decades and May Outperform Fluoride

American Dental Association representatives have described a fluoride-free mineral used in some alternative toothpastes as a trendy social-media newcomer, but research stretching back more than 50 years tells a different story.

In a segment for National Public Radio’s “Healthy or Hype” series, several dentistry academics discussed hydroxyapatite and suggested that the fluoride-free ingredient is recent and under-researched. But oral-care research on hydroxyapatite can be traced to Japan in the early 1970s, and the mineral has long been used in many countries outside the United States.

The segment featured Dr. Jin-Ho Phark, a dentistry practitioner at the University of Southern California and an ADA consumer advisor spokesperson.

Phark said students and patients have asked him about hydroxyapatite, adding that the product is being heavily promoted by influencers and others on social media.

Another ADA consumer advisor spokesperson, Dr. Ada Cooper, told NPR by email that research on the ingredient is new and that evidence of its clinical effectiveness remains limited and unclear, especially when it comes to clinical uses.

Even so, the ingredient marketed as new in the U.S. has been a common dental material in Japan for more than four decades and has substantial research backing its use in Europe.

“Hydroxyapatite is one of the most studied biomaterials in the medical field for its proven biocompatibility and for being the main constituent of the mineral part of bone and teeth,” a 2014 study in the Italian Journal of Odontostomatologic Sciences found. “In terms of restorative and preventive dentistry, nano-hydroxyapatite has significant remineralizing effects on initial enamel lesions, certainly superior to conventional fluoride, and good results on the sensitivity of the teeth.”

The study also noted that the mineral’s ability to bond chemically to bone, encourage bone growth, and avoid inflammation has made it widely used in periodontology and in oral and maxillofacial surgery.

NASA first developed the enamel-repair technology in 1972 to help counter mineral loss in astronauts during spaceflight.

A few years later, the Japanese biometric company SANGI acquired the patent from NASA and began researching and mass-producing the mineral in 1978. SANGI went on to become the first company in the world to create a hydroxyapatite toothpaste using “the same substance as our teeth,” and the product became widely used across Japan. The company also developed toothpastes, toothbrushes, and mouthwashes focused on enamel remineralization.

In the United States, fluoride still dominates oral care, even as Health and Human Services Secretary Robert Kennedy Jr. has raised concerns about the widely used chemical.

NPR reported that the CDC continues to support fluoride use and cited the agency’s 1999 ranking of fluoridated drinking water as one of the top 10 public health achievements of the 20th century, alongside vaccinations and family planning.

The CDC has also said that fluoride in water reduces cavities by 25 percent, according to NPR.

Although recent American studies have shown hydroxyapatite can be just as effective as fluoride, the ADA still recommends that people brush twice a day for two minutes with fluoride toothpaste.

A 2019 study published in Medical Science Monitor found that 59.4 percent of dentists were concerned about fluoridated toothpaste, and 31 percent worried about the risks of swallowing it and the possible development of dental and skeletal fluorosis.

A 2025 study in the International Dental Journal found that hydroxyapatite was a more effective toothpaste for rebuilding teeth and preventing decay, particularly in young children, than fluoride.

“While most of the literature on fluoridated toothpaste has demonstrated its ability to prevent the development of caries [tooth decay] … there is low to moderate scientific evidence that fluoridated toothpaste can reverse caries activity by achieving a remineralizing effect of the lesion,” the study found.

By contrast, the study said hydroxyapatite has a documented record of helping rebuild minerals in decayed teeth.

“Hydroxyapatite, a natural component of tooth enamel, has the ability to remineralize and desensitize exposed dentin surfaces by forming a protective layer that blocks dentinal tubules, reducing the transmission of external stimuli that cause sensitivity,” it found.