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659ef8d7d42cb6001e052645 Nanohydroxyapatiteprimary

The synergistic power of nano-hydroxyapatite and vitamins for oral health

Jan. 23, 2024
As clinicians, we have the opportunity to prevent oral disease and promote oral and systemic wellness. Here's a look at how nano-hydroxyapatite can work with vitamins to build and maintain children's dentition.

In honor of Children’s Dental Health Month, we celebrate the younger folks and the opportunities for prevention we have as clinicians. Here's a look at how using vitamins along with a mineral, ­nano-hydroxyapatite, can help build and maintain children’s dentition.

The role of vitamin D

To be clear, vitamin D is not a vitamin; it’s considered a hormone and is responsible for increasing absorption of calcium, magnesium, and phosphate. Vitamin D3, or cholecalciferol, is a type of vitamin D made by the skin through sunlight exposure. Vitamin D2, or calciferol, can be gotten from plants but is less effective than D3 for raising blood levels of D.

Vitamin D is necessary for several bodily functions, including management of calcium levels, supporting healthy bones and immune systems, reducing inflammation, and glucose metabolism. Vitamin D and calcium are needed for muscle movement and nerve communication, and those sunlight beams help support sleep and may protect against type 1 diabetes, multiple sclerosis, and several forms of cancer.1

The role of sunlight

Sunlight is the bright shiny object for health. It begins the process of producing vitamin D in the body. When UVB rays hit the skin, they interact with a protein, 7-dehydrocholesterol (DHC), helping to produce vitamin D3. Unfortunately, the increase of time spent indoors, whether due to lifestyle or work, along with protection of the skin from sun damage, creates a deficiency in the amount of sunlight that is needed for the vitamin process.

The role of diet

Diet is always important for health and wellness, but its contribution is small in the building of D3. Supplementation is recommended by many doctors for patients who have tested low or are at risk. Higher risk individuals may be those who are homebound, older, with dark skin pigmentation, obese, have digestive issues, and people on certain medications that interfere with vitamin D metabolism.2,3 Forty to sixty percent of the US population is vitamin D deficient, including pregnant women.4 Hopefully, obstetricians mention to their patients how important D3 is for not only reducing pregnancy complications but also for building babies’ bones and teeth.5

The relationship between vitamin D and calcium

Vitamin D plays an important role in helping our bodies absorb calcium from the intestines. If a child doesn’t get enough vitamin D, it doesn’t matter how much calcium they eat; their body won’t be able to use it properly for healthy bones.

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How do we get children more vitamin D? Without sunlight exposure, parents can try the vitamin D food route. Fatty fish, cod liver oil, wild caught salmon, canned sardines, fresh shiitake mushrooms, and egg yolks all contain vitamin D. However, many of these foods are not favorites of small children. Foods such as milk, orange juice, infant formula, yogurt, butter, cheese, and breakfast cereals are often fortified with vitamin D, which helps tremendously.

Vitamin D and dental caries

Dental health can be compromised with a deficiency in vitamin D for the young and old alike. The body manages minerals through a calcium balance and the immune system, which are both regulated by vitamin D.6 Research has shown a 49% decrease in decay among people who took vitamin D3, and children with severe childhood cavities had much lower vitamin D levels than children without.7,8

Vitamin K and dental health

Let’s not forget vitamin D’s friend, vitamin K, a fat-soluble vitamin discovered in 1929 that has two types. The original discovery was named koagulationsvitamin from the German word for coagulation, since the vitamin has essential blood clotting properties. We now call it K1, and it is found in green leafy vegetables such as spinach and kale.

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K2 has 10 subtypes and lasts longer than K1. It is found in animal and fermented foods such as natto, sauerkraut, and some cheeses, and can be produced by gut bacteria in the large intestine. People with gastrointestinal disorders and chronic diseases, such as celiac, ulcerative colitis, and cystic fibrosis, may not absorb vitamin K properly.

Calcium absorption and vitamins

K2 is proving to be as important as vitamin D for dental health, but we still have a lot to learn. Although vitamin D is needed for adequate calcium absorption, vitamin K2 directs the calcium to the skeleton to prevent the calcium from being deposited in the wrong areas.

If calcium is taken in isolation without other nutrients such as magnesium, vitamin D, and vitamin K, it can lead to the buildup of plaque in coronary arteries. A 2008 study showed that improving vitamin K status in children over a two-year period resulted in stronger and denser bones.9

In the last five decades, vitamin K2 intake among parents and their children has decreased significantly. Low vitamin K status is much more frequent in newborns due to both endogenous and exogenous insufficiencies.10 An ongoing clinical trial is testing whether vitamin D3 and K2 supplementation might positively influence the biological process of bone healing.

Oral health recommendations

Setting the stage for a lifetime of good oral health begins with the development of teeth. This is an area where we can counsel expectant mothers, helping their babies develop strong bones, strong teeth, and strong health.

An adult supplement with a D3 and K2 combo may help pull calcium out of circulation and into bones. For children, an oral supplement may be difficult, but dentistry has come a long way in helping them have strong, healthy dentitions. Product options are growing by leaps and bounds for lowering decay risk and building solid foundations. Nano-hydroxyapatite or xylitol added to products in our home-care routines can make a difference.

Keep the science in mind when trying out new products. Nano-hydroxyapatite is an expensive ingredient and if not included in a product at an adequate level the efficacy may be compromised.

Nano-hydroxyapatite is a calcium phosphate, and vitamin D helps the digestive system absorb the calcium. Add K2, which helps activate the proteins needed to take the calcium into the teeth and bones, and you have a great combo.

New and natural alternatives provide more options not only for adults but also for children’s oral health. The elimination of sodium lauryl sulfate, artificial sweeteners and flavors, and preservatives gives parents more choices, but products must work, scientifically. Understanding the route of calcium into our teeth and bones is one piece of the puzzle when making recommendations to parents.

Editor's note: This article appeared in the January/February 2024 print edition of RDH magazine. Dental hygienists in North America are eligible for complementary print subscription. Sign up here.


  1. van der Rhee HJ, de Vries E, Coebergh JW. Regular sun exposure benefits health. Med Hypotheses. 2016;97:34-37. doi:10.1016/j.mehy.2016.10.011
  2. Sizar O, Khare S, Goyal A, Givler A. Vitamin D deficiency. StatPearls. National Library of Medicine. Updated July 17, 2023. Accessed December 7, 2023.
  3. Vitamin D deficiency. Medline Plus. National Library of Medicine. Accessed December 7, 2023.
  4. Vitamin D and pregnancy. American Pregnancy Association. Accessed October 5, 2023.
  5. Pérez-López FR, Pilz S, Chedraui P. Vitamin D supplementation during pregnancy: an overview. Curr Opin Obstet Gynecol. 2020;32(5):316-321. doi:10.1097/GCO.0000000000000641
  6. Botelho J, Machado V, Proença L, Delgado AS, Mendes JJ. Vitamin D deficiency and oral health: a comprehensive review. Nutrients. 2020;12(5):1471. doi:10.3390/nu12051471
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  8. Schroth RJ, Jeal NS, Kliewer E, Sellers EA. The relationship between vitamin D and severe early childhood caries: a pilot study. Int J Vitam Nutr Res. 2012;82(1):53-62. doi:10.1024/0300-9831/a000094
  9. van Summeren MJ, van Coeverden SC, Schurgers LJ, et al. Vitamin K status is associated with childhood bone mineral content. Br J Nutr. 2008;100(4):852-858. doi:10.1017/S0007114508921760
  10. Kozioł-Kozakowska A, Maresz K. The impact of vitamin K2 (menaquionones) in children’s health and diseases: a review of the literature. Children. 2022; 9(1):78. doi.10.3390/children9010078

Anne O. Rice, BS, RDH, CDP, FAAOSH, founded Oral Systemic Seminars after almost 30 years of clinical practice and is passionate about educating the community on modifiable risk factors for dementia and their relationship to dentistry. She is a certified dementia practitioner, a longevity specialist, a fellow with AAOSH, and a consultant for Weill Cornell Alzheimer’s Prevention Clinic, FAU, and Atria Institute. Reach out to Anne at

About the Author

Anne O. Rice, BS, RDH, CDP, FAAOSH

Anne O. Rice, BS, RDH, CDP, FAAOSH, founded Oral Systemic Seminars after almost 30 years of clinical practice and is passionate about educating the community on modifiable risk factors for dementia and their relationship to dentistry. She is a certified dementia practitioner, a longevity specialist, a fellow with AAOSH, and has consulted for Weill Cornell Alzheimer’s Prevention Clinic, FAU, and Atria Institute. Reach out to Anne at

Updated May 31, 2024