Fluoride has long been the standard ingredient in anti-cavity toothpaste — it’s probably a part of your current oral hygiene routine — but modern oral care brands have recently been bringing attention to another science-backed alternative: hydroxyapatite. Despite having over four decades of research and dental care applications to back it up, hydroxyapatite is still not as widely known as fluoride, but is becoming more popular. And because it’s nontoxic and biocompatible, it’s a viable option for those seeking alternative oral care solutions. Read on to learn more about this dentist-approved ingredient and find the best hydroxyapatite toothpastes for you.
What is hydroxyapatite?
“Hydroxyapatite (HAp) is the main component of enamel and one of the most studied biomaterials in the medical and dental field,” Dr. Jonathan B. Levine, the chief dental officer of Lenny Kravitz’s oral wellness brand Twice, said. “It makes up the main mineral part of bones and teeth — in fact over 90% of the foundation of enamel.” Maintaining healthy enamel is essential to your oral and overall wellness. As the outermost layer of the teeth and the hardest substance in the human body, it protects the inner elements of the teeth from bacteria and decay; exposing those inner elements can lead to cavities, serious infections, gum disease and even tooth loss.
According to Dr. Daniel Naysan, a cosmetic dentist and the founder of Bedford Dental Group, hydroxyapatite toothpastes are a solid option for people who are focused on aesthetics (as a smoother mineral layer on the surface of teeth reflects light better, enhancing a brighter smile); looking to support their enamel; experiencing tooth sensitivity; seeking fluoride-free options; wanting to support a balanced oral microbiome; or maintaining a low to moderate risk of developing cavities.
Is hydroxyapatite safe?
Medical applications of hydroxyapatite were spearheaded by NASA in the 1970s, as astronauts lost minerals in their teeth and bones due to the lack of gravity in space. In 1974, the Japanese company Sangi Co. Ltd. acquired a patent from NASA to use hydroxyapatite in the dental field, eventually creating the world’s first nano-hydroxyapatite toothpaste in 1980 and patenting the ingredient in 1990.
“In small particle size — micro or nano — HAp helps to form a protective layer on the enamel and the cementum root surface,” Levine said. This is a process called remineralization, where the hydroxyapatite bonds to the enamel and fills tubules (microscopic channels that go inside the tooth and can cause sensitivity when exposed). “Because enamel is composed largely of hydroxyapatite, HAp toothpaste supports natural remineralization and strengthens the tooth surface,” Dr. Ellen Katz, dentist and cofounder of Maison BE Dental Studio, added.
Hydroxyapatite is a safe alternative to fluoride, but it is also safe to use with fluoride, and some toothpaste formulas combine the two ingredients for more benefits. “Both hydroxyapatite and fluoride are minerals that can repair the damage from tooth decay,” Dr. Chris Salierno, chief dental officer at Tend, said. “Fluoride can kill the bacteria, while hydroxyapatite prevents the bacteria from adhering to the teeth.”
While fluoride has made headlines over the the years as skeptics have questioned its safety, the American Dental Association (ADA) recognizes and supports the use of fluoride in dental products and water supply as a safe and effective way to prevent tooth decay. “HAp does not have the controversial issues of too much fluoride and is safer in the minds of many people,” Levine said, although the dentist notes that because we don’t swallow toothpaste in large amounts, fluoride is “100% safe to use and necessary for certain people who require the strong efficacy for weaker enamel that fluoride provides.” Swallowing small amounts of fluoride is not harmful and should not be a sole reason to avoid using fluoride toothpaste.
Benefits of hydroxyapatite
The remineralization of tooth enamel is the primary benefit of hydroxyapatite. By strengthening the enamel, the teeth are better protected against plaque, which can cause cavities and gum disease. While fluoride also defends against tooth decay, it doesn’t contain calcium and phosphate. These minerals are found in hydroxyapatite and tooth enamel, which further helps prevent tooth decay. “[Hydroxyapatite] works behind the scenes to prevent cavities from forming or advancing,” Salierno said.
Because hydroxyapatite is naturally occurring in our bodies, it is nontoxic and biocompatible, which also makes it a better option for kids who may accidentally swallow toothpaste as they’re learning to brush their teeth. (Again, fluoride is safe to swallow in small quantities.)
While you won’t see the benefits of hydroxyapatite — tooth enamel is semi-translucent and Levine said “tooth remineralization happens at the micron level” — you may be able to feel them. Hydroxyapatite helps ease tooth sensitivity by filling the aforementioned tubules, which are essentially microscopic pathways to the nerves in the teeth. With fewer tubules exposed, the less sensitivity and discomfort you’ll feel to touch, food and temperature.
Now that you know the benefits of hydroxyapatite and whether it’s a fit for your needs, here are the hydroxyapatite toothpastes dentists recommend adding to your dental routine.