This is a current list of every study we’ve found on the safety and efficacy of hydroxyapatite toothpaste. We created this to be a resource for both patients and the functional dentistry community, so feel free to bookmark it, share it widely with your patients, and email us if you have a study to add.
I must give credit to Jacqueline Carcaramo, RDH (@the.flossophy on Instagram) who inspired this idea. When we both realized we were keeping our own repository of studies on this topic, we realized we could join forces and publish this database for the benefit of functional dentists and hygienists everywhere.
Studies on Hydroxyapatite Toothpaste Efficacy & Safety
Biomimetic hydroxyapatite and caries prevention: a systematic review and meta-analysis (2021)
Based on this systematic review and meta-analysis of over 291 studies of micro-Hydroxyapatite, the authors concluded there is good evidence that micro-Hydroxyapatite in oral care products in the absence of fluoride effectively reduces caries. They do not conclude on how much micro-Hydroxyapatite is ideal, but this more recent study (conducted after this review was published) mentions it should be around 10-15% for micro-Hydroxyapatite.
Dr. B’s Notes: Great summary of the literature about nano-hydroxyapatite, specifically the benefits of using nano-hydroxyapatite for its preventive, restorative, and regenerative applications in dentistry. Will give you an idea of the wide usage of nano-Hydroxyapatite in not only dentistry, but a wide range of applications in medicine as well.
Demineralized dentin infiltrated with silica NPs appears to encourage heterogeneousmineralizationof the dentin collagen matrix following exposure to an artificial saliva solution.
Reconsidering remineralization strategies to include nanoparticle hydroxyapatite.
This in-vitro study documented the deposition of nanoparticle hydroxyapatite on demineralized enamel surfaces after treatment with an experimental remineralization gel. This finding supports consideration of an additional approach to remineralization that includes pH neutralization strategies and nanoparticle hydroxyapatite crystals.
Effect of nano-hydroxyapatite concentration on remineralization of initial enamel lesionin vitro (2009)
Dr. B’s notes: This is an older study out of China which studied four different concentrations of nano-hydroxyapatite (1%, 5%, 10% and 15% by weight). The 10% and 15% demonstrated efficacy, however, this is for a micro particle of a non-uniform, off the shelf hydroxyapatite product in powder form, even though the study calls it “nano.” The important thing to understand here is that the concentration of hydroxyapatite in this study was calculated based on weight, not volume, like most toothpaste manufacturers do.
Remineralization Potential of Nano-Hydroxyapatite on Initial Enamel Lesions: An in vitro Study (2011)
Dr. B’s Notes: The remineralization effect of nano-Hydroxyapatite increased significantly when the pH was less than 7. Why is this important? You’re going to hear a lot of people say that for remineralization to occur, pH needs to be neutral or higher, but this incorrect; the pH must be between 5.5 and 6.5 in order for there to be ion exchange (in this case, remineralization). The percentage of surface microhardness recovery and integrated mineral loss obtained from CSMH tests demonstrated that nano-HA provides better remineralization than micro-HA.
Combined Effects of Nano-Hydroxyapatite and NaF on Remineralization of Early Caries Lesion
The aim of this study was to evaluate the combined effects of a nano-HA and fluoride mouthrinse on an early caries lesion in human enamel using an in vitro cycle remineralization and treatment model.
Effectiveness of nano-hydroxyapatite toothpaste in reducing dentin hypersensitivity: a double-blind randomized controlled trial
A double-blind randomized clinical trial that compared the efficacy in reducing dentin hypersensitivity of a dentifrice formulation containing nano-hydroxyapatite with a fluoride dentifrice and a placebo.
Nano-HA and NAF mouthrinses can greatly enhance remineralization and increase tooth microhardness.
Remineralization Potential of New Toothpaste Containing Nano-Hydroxyapatite
The results showed that there were no significant differences in Vickers Hardness Number values between the two toothpastes (P>0.05). A toothpaste containing nano-sized hydroxyapatite has the potential to remineralize an incipient caries lesion. In addition, the addition of fluoride had no synergistic effect on remineralization.
Dr. B’s Notes: This study was performed in vitro and in vivo—you don’t see that too often!
Comparison of hydroxyapatite and fluoride oral care gels for remineralization of initial caries: a pH-cycling study (2020)
Dr. B’s notes: Peer-reviewed study demonstrating 15% micro-Hydroxyapatite-based gel (15% HAP) was as effective as fluoride-based gel (at 12,500 ppm, which is even stronger than Prevident 5000) in remineralizing initial caries lesion.
Enamel and dentine remineralization by nano-hydroxyapatite toothpastes
Toothpastes containing n-HAp revealed higher remineralizing effects compared to amine fluoride toothpastes with bovine dentine, and comparable trends were obtained for enamel.
Remineralization of early caries by a nano-hydroxyapatite dentifrice
The purpose of this randomized, double-blind, crossover, in situ study was to evaluate the efficacy of nano-hydroxyapatite (nHAP) dentifrices on caries remineralization and demineralization inhibition. nHAP dentifrice caused remineralization comparable to a fluoride dentifrice, and inhibited caries development, thus suggesting that an nHAP dentifrice can be an effective alternative to fluoride toothpaste.
Synthetic Biomimetic Carbonate-Hydroxyapatite Nanocrystals for Enamel Remineralization (2008)
Dr. B’s Notes: Just another early study out of Italy that supports the idea that nano-Hydroxyapatite is great at remineralizing teeth.
- HApNPs allowed Ca2+and PO43−release in low pHs.
- HApNPs enable remineralization of caries-like enamel lesions.
This study investigated the ability of hydroxyapatite nanoparticles (nano-HA) to remineralize enamel, and their effect on sealant microleakage and shear bond strength (SBS).
Nano-hydroxyapatite toothpaste ingredient for teeth remineralization and sensitivity
