Dentists urge patients to stick with fluoride despite rising demand for hydroxyapatite

The Centers for Disease Control and Prevention report that adding fluoride to public drinking water reduces cavities by 25 percent. That statistic has long been a cornerstone of dental health, but a growing number of Americans are now looking for alternatives to the mineral in their toothpaste.

Dr. Jin-Ho Phark, an associate professor of clinical dentistry at the University of Southern California, says his practice has seen a surge in questions about fluoride-free options. Patients are increasingly asking about hydroxyapatite, a calcium phosphate mineral. Phark notes that many of these patients first encountered the products on social media, where influencers have pushed them aggressively.

The shift is part of a longer history of skepticism toward fluoride. Health Secretary Robert F. Kennedy Jr. has linked water fluoridation to a range of health issues, including arthritis, bone fractures, and thyroid disease. Bennett Amaechi, a professor of dentistry at the University of Texas at San Antonio, observes that more people are refusing fluoride entirely or hesitating to give it to their children. This has created a market opening for hydroxyapatite, which mimics the mineral composition of tooth enamel.

Traditional fluoride toothpaste became common in the late 1950s after Procter & Gamble released Crest nationally. Fluoride works by remineralizing teeth. Dr. Livia Tenuta, a dentist at the University of Michigan School of Dentistry, explains that fluoride left in the mouth after brushing combines with calcium and phosphate to form a protective shield over the enamel. Hydroxyapatite works differently. Nano-hydroxyapatite particles are designed to penetrate tiny crevices in the enamel to help repair damage.

The research on hydroxyapatite is promising but young. Amaechi co-authored a 2021 study in Scientific Reports that tracked 177 children for nearly a year. The study found that children using hydroxyapatite toothpaste had similar tooth decay outcomes to those using fluoride. That research was funded by the Dr. Wolff Group, a German company that owns two hydroxyapatite toothpaste brands. A 2023 study in Frontiers in Public Health followed 171 adults for 18 months and found similar results, though the participants were mostly healthy young adults with low risk of cavities.

Tenuta points out that most existing studies have recruited participants with low caries risk. She would like to see more long-term data, particularly for people at high risk for tooth decay. A 2019 study in the Journal of Investigative and Clinical Dentistry did test the product on 133 high-risk individuals. After five months, the researchers found that both toothpaste types performed similarly.

Hydroxyapatite toothpastes generally cost more than their fluoride counterparts. Some brands charge over a dollar more per ounce. For patients who are open to either option, Amaechi advises choosing fluoride because of the extensive long-term evidence supporting its efficacy. Tenuta agrees, calling fluoride the best option due to the volume of data available.

The American Dental Association acknowledges that more people are using hydroxyapatite products. Dr. Ada Cooper, the ADA Consumer Advisor spokesperson, wrote in an email that while some evidence suggests these products contribute to remineralization, the research remains limited. The ADA continues to recommend brushing twice a day for two minutes with fluoride toothpaste, flossing daily, and visiting a dentist regularly.

Phark says he hears the interest from students as well as patients. The debate over fluoride is no longer confined to municipal water systems. It has moved into the bathroom cabinets of working families who are weighing cost, health concerns, and the latest social media trends when they choose what to put on their toothbrush.