Does Hydroxyapatite Toothpaste Work?

Written by: Cass Nelson-Dooley, MS, Author of Heal Your Oral Microbiome

We all want the perfect toothpaste. One that whitens, brightens, cleans, strengthens, and protects from cavities. And we don’t want the problems that can come with some toothpaste brands. We don’t want unnecessary ingredients that can cause harm such as SLS (sodium lauryl sulfate), triclosan, or cocomidopropyl betaine. We don’t want irritation to the mouth, inflammation, or mouth sores. We want a toothpaste that protects our beneficial oral bacteria while warding off the bad. That’s why it matters what you use to brush your teeth every day. Read more about hydroxyapatite, fluoride, the evidence, and what to consider when picking a toothpaste. 

What is Hydroxyapatite?

Hydroxyapatite is the fundamental hard ingredient in teeth and bones, made from calcium, phosphorus, oxygen, and hydrogen. Hydroxyapatite has been used in medicine and dentistry for more than six decades. Certain hydroxyapatite combinations are nearly identical in chemical structure to that found in teeth.¹ For this reason hydroxyapatite has been called a bionic material, having the same capability as if it were a living biological material. Available as a toothpaste ingredient, hydroxyapatite fights cavities on par with fluoride and has been suggested as an alternative to fluoride.^2,3 

Fluoride Toothpaste: A Two-Sided Coin

Fluoride does so many great things for teeth. Why would we ever need an alternative?

Fluoride treatments strengthen and rebuild teeth- the evidence is clear. Calcium, found in the tooth’s hard hydroxyapatite material, can be swapped out for fluorine (aka fluoride), which makes teeth more durable and less susceptible to cavities.⁴ The World Health Organization recommends brushing twice daily with fluoride toothpaste to prevent cavities. 

However, there is a dark side to fluoride toothpaste. Fluoride is toxic to all cell types,⁵ kills oral bacteria,⁶ can cause brown mottling of teeth (fluorosis), and may cause neurotoxicity.⁷ There is a possibility of fluoride poisoning in children.8 Researchers are keen on finding an effective non-fluoride toothpaste for young children.

The topic of fluoride versus hydroxyapatite for dental health is hotly debated. It may never be settled. The good news is you have a choice. I urge you to do your research, talk with your dentist, and use fluoride carefully. Consider hydroxyapatite toothpaste for children, who can be more vulnerable to the negative effects of fluoride than adults. 

Does Hydroxyapatite Toothpaste Work?

Fluoride has stiff competition from hydroxyapatite. Taken head-to-head in the research, hydroxyapatite can match fluoride’s benefits for teeth- over and over again. 

One of hydroxyapatite’s crowning glories is this- it is safe and well-tolerated. You don’t have to worry about irritation, inflammation, or damage to the oral microbiome. 

You know what else gives me confidence in hydroxyapatite? 

It’s the natural way we start out. It’s the reason we have strong, healthy teeth in the first place. You don’t need to reinvent the wheel when it comes to fortifying teeth. Just use hydroxyapatite toothpaste! 

Scientific Studies Show that Hydroxyapatite:

• Brightens teeth^8,9
• Builds and heals bone¹
• Decreases tooth sensitivity and pain^8,9
• Fights cavities to the same degree as fluoride^1,8,9
• Has a long history of safe use
• Makes the tooth surface smoother⁹
• Promotes a remineralizing environment in the mouth for building teeth (extra calcium and phosphate)¹
• Reduces demineralization (tooth breakdown)⁸
• Regenerates and repairs enamel⁸
• Strengthens teeth by rebuilding them^1,8
• Works differently than fluoride¹

What Does “Remineralizing” Toothpaste Mean?

Teeth are made of calcium and phosphate minerals, so remineralization of teeth means that more of these minerals are added to the structure of the tooth. Remineralizing toothpaste claims to build teeth. “Demineralizing” is the opposite- the breakdown of the tooth's mineral structure. Calcium and phosphate ions fall away from teeth. Demineralization is not a healthy state to be in because it is a prerequisite for tooth decay. The acidic pH present in a demineralized mouth encourages bad bacteria to grow and it harms the oral microbiome. When teeth are broken down and vulnerable, they are easily damaged by bacteria or their acidic byproducts. It is better to have a remineralization environment in the mouth to continually support healthy tooth structure.

Hydroxyapatite Toothpastes Popular Around the World and Even in Space

The United States has been late to adopt hydroxyapatite toothpaste even though it was invented in the US. Synthetic hydroxyapatite toothpaste was developed by NASA (National Aeronautics and Space Administration) for astronauts who were losing bones and teeth due to the absence of gravity. A Japanese company bought the rights in 1970 and launched the first hydroxyapatite toothpaste. In 1993, hydroxyapatite was approved as an anti-cavity substance in Japan. It became commercially available in Europe in 2006. And in 2015, it was released to the Canadian public.⁹ Around the world, there is continued research into hydroxyapatite toothpaste, particularly as a non-fluoride toothpaste alternative for children.

What is the Difference Between Nano-hydroxyapatite and Hydroxyapatite Toothpaste?

Hydroxyapatite crystals can be microparticles or nanoparticles. It has to do with the size of the hydroxyapatite crystals. Nano-hydroxyapatite may have more benefits because it is more similar to the natural tooth mineral structure. The ideal nano-hydroxyapatite concentration is 10%.^8,9

Hydroxyapatite and the Oral Microbiome

Hydroxyapatite seems to prevent bacteria from attaching to teeth without killing them. It reduces bad bacteria like the one implicated in cavities, Streptococcus mutans. When compared to an antibiotic mouthwash, hydroxyapatite had a similar effect- not because it killed bacteria, but because they had a harder time holding on to teeth. Hydroxyapatite appears to be harmless to the friendly oral bacteria that help prevent disease in the mouth. It may be able to ward off oral pathogens, spare friendly oral bacteria, and build tooth structure at the same time.^9,10

Learn more about the oral microbiome in my book, Heal Your Oral Microbiome or by signing up for my e-newsletter.

Choose Your Toothpaste Carefully

Both fluoride-containing toothpaste and hydroxyapatite toothpaste strengthen teeth and fight cavities. One critical difference is that hydroxyapatite has a remarkable safety profile that has stood the test of time. It’s a safer alternative to fluoride for children under six years old. And if they swallow it, there is no problem because it is harmless. Hydroxyapatite also excels because it is a great agent to rebuild tooth structure. Its mechanism of action closely resembles our body’s own tooth-building processes (known as remineralization) while it reduces sensitivity and brightens teeth. Talk with your dental team and do your research to pick the best toothpaste for you and your family.  

References

1. Limeback H, Enax J, Meyer F. Biomimetic hydroxyapatite and caries prevention: a systematic review and meta-analysis. Can J Dent Hyg. Oct 2021;55(3):148-159. 
2. Bossù M, Saccucci M, Salucci A, et al. Enamel remineralization and repair results of Biomimetic Hydroxyapatite toothpaste on deciduous teeth: an effective option to fluoride toothpaste. Journal of nanobiotechnology. Jan 25 2019;17(1):17. doi:10.1186/s12951-019-0454-6
3. Paszynska E, Pawinska M, Gawriolek M, et al. Impact of a toothpaste with microcrystalline hydroxyapatite on the occurrence of early childhood caries: a 1-year randomized clinical trial. Sci Rep. Jan 29 2021;11(1):2650. doi:10.1038/s41598-021-81112-y
4. Abou Neel EA, Aljabo A, Strange A, et al. Demineralization-remineralization dynamics in teeth and bone. Int J Nanomedicine. 2016;11:4743-4763. doi:10.2147/IJN.S107624
5. Tabatabaei MH, Mahounak FS, Asgari N, Moradi Z. Cytotoxicity of the Ingredients of Commonly Used Toothpastes and Mouthwashes on Human Gingival Fibroblasts. Front Dent. Nov-Dec 2019;16(6):450-457. doi:10.18502/fid.v16i6.3444
6. Shang Q, Gao Y, Qin T, Wang S, Shi Y, Chen T. Interaction of Oral and Toothbrush Microbiota Affects Oral Cavity Health. Front Cell Infect Microbiol. 2020;10:17. doi:10.3389/fcimb.2020.00017
7. Malin AJ, Till C. Exposure to fluoridated water and attention deficit hyperactivity disorder prevalence among children and adolescents in the United States: an ecological association. Environ Health. Feb 27 2015;14:17. doi:10.1186/s12940-015-0003-1
8. Anil A, Ibraheem WI, Meshni AA, Preethanath RS, Anil S. Nano-Hydroxyapatite (nHAp) in the Remineralization of Early Dental Caries: A Scoping Review. International journal of environmental research and public health. May 5 2022;19(9)doi:10.3390/ijerph19095629
9. O'Hagan-Wong K, Enax J, Meyer F, Ganss B. The use of hydroxyapatite toothpaste to prevent dental caries. Odontology / the Society of the Nippon Dental University. Apr 2022;110(2):223-230. doi:10.1007/s10266-021-00675-4
10. Meyer F, Enax J. Hydroxyapatite in Oral Biofilm Management. Eur J Dent. May 2019;13(2):287-290. doi:10.1055/s-0039-1695657