Hydroxyapatite: A way to brush your teeth with their natural components?

Nature has repeatedly shown us its self-healing abilities. We know that if human existence disappeared, plants and trees would reclaim the earth. If we scratch our arm, our blood platelets rush to coagulate the area, scab over and close. The components of our body are created in such a way that they can withstand a certain extent of injury and cyclically attempt to repair anything that threatens survival. The world we live in has external factors that can cause injuries to the body, some of which are beyond our control and some within it. Our body does the best it can based on the current state it is in to repair its weaknesses and keep functioning. As the gateway to the body and the starting point for digestion, the mouth is vulnerable to constant attack from various sources. An ingredient called hydroxyapatite (HAP), the main constituent of tooth enamel and bone, has made a statement in the field of tooth remineralization.

The type of food we eat, the way we wash our mouths, smoking, drinking alcohol, breathing through our mouths, contact with certain chemicals and chronic stress are just a few. -one of the factors that contribute not only to the health of the mouth but to the health of the body. These factors can cause the pH of the mouth to fluctuate repeatedly and increase the risk of tooth decay. By placing HAP back on the teeth, we replenish the very material that the teeth are made of, helping to remineralize the teeth.

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As a naturally occurring form of calcium, this is how our teeth are formed (97% of our tooth enamel and 70% of our tooth dentin); PAHs should be a no-brainer when it comes to substances capable of remineralizing our teeth. It is also the main component of our bones and is commonly used in osteopathic medicine for bone repair as it stimulates osteoblasts (bone-creating cells). The use of PAHs in oral care products may be an under-explored and long-awaited revelation in the dental industry.

Benefits of hydroxyapatite

The advantages of this biomimetic ingredient are that once we put it on the teeth, the body knows what to do with it because it is already a familiar component. The small particles adhere to the tooth structure and fill in weaker, demineralised areas, bond to the tooth and create a stronger surface. It can also decrease sensitivity and make teeth look whiter. For maximum benefit, it is recommended to leave the toothpaste on the teeth and not rinse it off. HAP is also non-toxic; if swallowed, there are no worries and it is also safe for children.1

We are used to using and recommending fluoride products, but why can’t we be open to something different, especially when there is scientific evidence to back it up? With tooth decay being one of the world’s most preventable diseases and fluoride ingestion being a concern, especially for children, where can we turn? A need for effective fluoride-free products prevails, and HAP has proven to be that rising star.

Nano- and microhydroxyapatite

There are two types of PAHs: nano and micro. Nano-PAH particles have particle sizes between 20 and 80 nanometers, while micro-PAH particles are 5-10 microns in length.2 There are toothpaste brands on the market with both particle sizes. One of the main differences is that nano-PAH is usually synthetic and micro-PAH usually comes from natural sources, such as cow cattle. Nano-HAP has proven to be a better remedy for those who suffer from tooth sensitivity since the particles are smaller and can cling to a larger surface area, but both have shown promising effects on tooth sensitivity.3 It may be difficult for these hardcore fluoride advocates to understand, but HAP has been proven time and again to be just as effective as its long-lasting counterpart.

It’s not that fluoride isn’t effective; it has been proven to be over years of study and has shown great success in decreasing cavity rates.4 Nevertheless, with the ever-growing root cause medicine movement, people are beginning to want alternatives to products that may cause harm. For example, a bottle of toothpaste containing fluoride must have a warning label in case a child swallows more than recommended.5 Additionally, there may be fluoride in the water, and a child may also receive fluoride varnish from the dentist, in addition to ingesting prescribed fluoride supplements. Even so, these children may still have dental caries due to other factors such as diet, airways, or myofunctional issues. A particular type of fluoride, called stannous fluoride, has been shown to kill cavity-causing bacteria in the mouth, but it also kills some of the beneficial bacteria.⁶ This can disrupt the oral microbiome, leaving room for other oral health imbalances. HAP does not kill bacteria; it simply prevents harmful bacteria from attaching.seven Clinicians should educate parents about these possible components that lead to tooth decay before defaulting to fluoride. We should suggest options as to what will work best for the child so parents can make an informed decision.

How does HAP work?

HAP acts by binding to the surface of the tooth and reconstructs the areas of demineralization. It naturally contains calcium and phosphate ions, which are crucial components for enamel remineralization. Research has shown that HAP can penetrate deeper layers of enamel further than fluoride and can reduce bacterial colonization.8 Another study compared HAP to chlorhexidine mouthwash and found that it was equally effective in reducing bacterial colonization, but without killing any bacteria and instead repelling bacteria from the enamel. Chlorhexidine works by killing bacteria, which creates dysbiosis of the oral microbiome.9 This makes HAP a promising biomimetic active ingredient for reducing dental caries.

For maximum benefit, HAP toothpaste should be left on the teeth and not rinsed out. The same can be said for fluoride, but it creates a greater risk of swallowing more fluoride than recommended.ten

Those who believe that there is only one folk remedy for cavities may feel like dismissing the idea that something new is emerging in their well-known world of dentistry. Learning to adapt and stay open-minded is the most effective way to keep up with our ever-changing world. Professionals can share an alternative with those who refuse fluoride and still feel good about creating a positive prevention strategy for them.

It is important to remember that cavities are preventable. A colorful diet, proper functioning of the respiratory tract and healthy lifestyle habits are imperative factors in reducing cavities. Fluoride is the go-to resource for people dealing with cavities, as well as a reliable method of prevention. A new alternative is gaining momentum and deserves more recognition. Hydroxyapatite toothpaste is here, and it’s part of who we are (literally). What should not be taken lightly is its ability to successfully remineralize tooth enamel thanks to its biomimetic characteristics, which reduces the occurrence of cavities. It’s encouraging to know that there are now so many ways to tackle one of the most preventable diseases on the planet.

Author’s note: I have teamed up with Dr. Mark Burhenne, also known as “Ask the Dentist”, to create a unique resource of scientific studies performed on PAHs. Discover us on theFlossophy.

Editor’s note: This article originally appeared in the September 2022 print edition of HDR magazine. Dental hygienists in North America are eligible for a free print subscription. Register here.


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  2. Legeros RZ, Legeros JP. Hydroxyapatite. nano today. 2014. Accessed February 18, 2022. https://www.sciencedirect.com/topics/chemical-engineering/hydroxyapatite
  3. Shreya S, Ramreddy Y, Karunakar S. Comparative evaluation of hydroxyapatite, potassium nitrate and sodium monofluorophosphate in office desensitizing agents – a double-blind randomized controlled clinical trial. J Oral health. 2013;1:104. doi:10.4172/2332-0702.1000104
  4. Kanduti D, Sterbenk P, Artnik B. Fluoride: a review of use and health effects. Mater Sociomed. 2016;28(2):133-137. doi:10.5455/msm.2016.28.133-137
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  6. Mitchell J. The Other Fluoride: The Benefits of Stannous Fluoride. Clumps now. March 20, 2013. Accessed August 4, 2022. https://now.tufts.edu/2013/03/20/other-fluoride-benefits-stannous-fluoride
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  8. Amaechi BT, AbdulAzees PA, Alshareif DO, et al. Comparative efficacy of hydroxyapatite and fluoride toothpastes for the prevention and remineralization of dental caries in children. open BDJ. 2019;5:18. doi:10.1038/s41405-019-0026-8
  9. Kensche A, Holder C, Basche S, Tahan N, Hannig C, Hannig M. Effectiveness of a hydroxyapatite-based mouthwash in reducing initial bacterial colonization in situ. Ark Oral Biol. 2017;80:18-26. doi:10.1016/j.archoralbio.2017.03.013
  10. “Spit, don’t rinse” for better oral health. Oral Health Foundation. June 6, 2016. Accessed February 19, 2022. https://www.dentalhealth.org/news/spit-dont-rinse-for-better-oral-health

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