Peer‑Reviewed · University of Texas Health

Clinically studied. Peer‑reviewed. Published.

Fygg's nanohydroxyapatite formula was tested head‑to‑head against seven leading toothpastes in a university‑led study - and delivered the highest remineralization of any product tested.

See the results
University of Texas
Health San Antonio
Journal of Dentistry
2025
Peer‑Reviewed
& Published
Indexed on
PubMed
"
I needed to know that what we're making actually works. Not that the ingredient works in someone else's formula — that our product works. So we invested in the research.
Dr. Mark Burhenne, DDS
Co-Founder, Fygg
The Study
"In vitro evaluation of the ability of nanohydroxyapatite toothpastes to enhance remineralization of enamel caries lesions"
Amaechi BT, et al. · UT Health San Antonio · J Dent. 2025;161:106006
Read on PubMed

Key Findings

0%
Highest Remineralization

Average enamel remineralization — the highest of all eight products tested in the study

Highest of 8 products
0
Highest of all brands tested

Statistically significantly higher than Boka, Dr. Jen, Clinical Grade HAP (Clin Pro), and Crest.

p < .05
0
Products Tested

Head‑to‑head comparison including fluoride controls at 1,100 and 5,000 ppm

Randomized · n=20/group

How Fygg compared

Mean % surface microhardness recovery after 14 days. All 8 products tested, including two fluoride controls.

Fygg
Fluoride controls
HAP competitors

Amaechi et al., J Dent 2025. In vitro, 14‑day pH‑cycling protocol.
* Statistically significantly lower than Fygg (p<.05).

Fluoride‑Free

Fluoride‑free.
Fluoride‑level results.

Fygg's remineralization outperformed and statistically matched prescription‑strength fluoride toothpaste in the study - without any fluoride present.

Performed on par with ClinPro 5000 - a prescription‑strength 5,000 ppm fluoride toothpaste
Performed on par with Crest Cavity Protection at 1,100 ppm fluoride
Zero fluoride. Full remineralization performance.
Fygg · 0 ppm Fluoride
39.8%
remineralization
=
ClinPro · 5,000 ppm Fluoride
Matched
equivalent remineralization

Equivalent performance in the study (p > .05)

How nanohydroxyapatite repairs enamel

1

Biomimetic match

Hydroxyapatite is already the primary mineral in your teeth - it makes up 97% of enamel. Our nanoXIM particles are the same material, so your body recognizes them and allows them to integrate directly into demineralized areas on the enamel surface.

2

Supports the Building Blocks

Fygg keeps calcium and phosphate ions available in saliva so the oral microbiome can integrate them into demineralized lesions, the earliest stage of a cavity, restoring surface hardness at the enamel level.

3

Strengthens over time

With consistent daily use, the effect compounds - building a smoother, stronger enamel surface that resists future acid attacks from food, drink, and bacteria.

Particle quality matters more than concentration.

The prevailing assumption is that 10% nanohydroxyapatite is the minimum effective concentration. This study challenges that. Fygg outperformed toothpastes containing 10% nanoHAP, 10% microHAP, and 15% microHAP — suggesting that the physicochemical properties of the particle are a more significant variable than concentration alone.

Fygg uses nanoXIM·CarePaste from Fluidinova (Maia, Portugal), a synthetic nanohydroxyapatite delivered as a 20% pre‑aqueous solution and added directly to our toothpaste at the time of production. The particles are rod‑shaped, with a median length of 27.6 nm and width of 15.4 nm - well below the 1.3 µm adhesion threshold identified in the literature. They are uncoated, not surface‑modified, and contain no needle‑shaped structures.

Critically, nanoXIM was engineered to conform to SCCS (Scientific Committee on Consumer Safety) guidelines for particle size, morphology, and whole‑body safety - a standard we selected specifically because it addresses both efficacy and safety simultaneously.

Biomimetic - Hydroxyapatite comprises 97% of enamel by weight. nanoXIM particles are structurally identical to the mineral already in your teeth.
Engineered to SCCS guidelines - Particle size, shape, aspect ratio, and composition designed from the ground up to meet EU safety committee standards for nano‑materials in consumer products.
Synthesized, not milled - Unlike HAP derived from grinding animal bones, salt‑phosphate reactions, or egg shells, nanoXIM is synthesized in aqueous solution — producing precise, consistent, sub‑50nm particles.
Sub‑50nm adhesion advantage - Research shows HAP particles above 1.3 µm have limited enamel adhesion. Conventional microHAP often exceeds 5 µm. nanoXIM particles are typically below 50 nm - enabling superior surface binding and remineralization.
Ca10(PO4)6(OH)2
Hydroxyapatite
nanoXIM · Fluidinova

Beyond the Active Ingredient

Remineralization doesn't happen in a sterile mouth.

Your mouth contains hundreds of bacterial species that regulate pH, recycle minerals, and protect enamel. What you leave out of a toothpaste matters as much as what you put in.

Every other brand in the study
Contains ingredients that work against the oral microbiome
Every competing product in the study contains surfactants, emulsifiers, or essential oils that disrupt the biological environment remineralization depends on.
✕Surfactants & SLS — Strip the mouth's protective biofilm. A 2024 study found SLS killed bacteria in both mature and developing biofilms and increased the proportion of pathogenic species. (4)
✕Essential oils — Antimicrobial by design. Research describes their mechanism as "non‑selectively" resetting the oral microbiome — they don't distinguish beneficial from harmful bacteria. (5)
✕No prebiotic support — Nothing to feed the beneficial species the mouth depends on for natural mineral cycling.
Fygg
Formulated to support the microbiome, not sterilize it
Instead of disrupting the ecosystem remineralization depends on, Fygg's formula is designed to work with it.
✓No surfactants or SLS — Oral biofilm stays intact. No stripping of the protective bacterial layer.
✓No essential oils — No non‑selective antimicrobial disruption of the microbial community.
✓Prebiotics included — Chicory root and xylitol feed the beneficial bacteria your mouth needs for natural pH regulation and mineral cycling.
✓L‑Arginine — Supports oral microbiome balance and helps maintain a neutral pH environment.
Fygg scored the highest remineralization of any product in the study. 20% nanoXIM is part of the reason. We believe the rest comes down to what isn't in the formula — nothing that undermines the microbiome your mouth depends on to remineralize in the first place.
References: (4) Shi Q et al. Effects of SLS on oral microecology. J Oral Microbiol. 2024;16(1):2372224. · (5) Min K et al. Effects of essential oil mouthrinses on clinical plaque microbiome. BMC Oral Health. 2024;24(1):578.

How the study was conducted

Phase 1 · Day 0–3

Lesion creation

160 bovine enamel specimens were demineralized using a multi‑species microbial caries model to create standardized early caries lesions.

Phase 2 · Randomization

Blinded assignment

Specimens randomly divided into 8 groups of 20 — Fygg, four competing HAP brands, and two fluoride controls (1,100 ppm and 5,000 ppm).

Phase 3 · 14 Days

Daily pH‑cycling

Each day: a 2‑minute acid challenge, three 2‑minute toothpaste treatments, and storage in artificial saliva — simulating the oral environment.

Phase 4 · Analysis

Measurement & statistics

Surface microhardness measured before and after. Analyzed by paired t‑tests and ANOVA/Tukey at α = 0.05 — the gold standard for statistical significance.

Engineered
for your microbiome

The highest‑performing toothpaste in a peer‑reviewed, university‑led study. Fluoride‑free. Published in the Journal of Dentistry.

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Published research
Transparency & Disclosures
This study was designed and conducted at the University of Texas Health San Antonio. Funding support was provided by Oral Microbiome Solutions, LLC, as disclosed in the published paper.
All results cited on this page are from an in vitro study using bovine enamel and a 14‑day pH‑cycling protocol. In vitro results may not directly predict clinical outcomes.
This product is not intended to diagnose, treat, cure, or prevent any disease. A corrigendum to the original study was published in J Dent. 2026;165:106308.
References
(1)Amaechi BT, Tan AI, Noureldin AAK, et al. In vitro evaluation of the ability of nanohydroxyapatite toothpastes to enhance remineralization of enamel caries lesion. J Dent. 2025;161:106006. PubMed
(2)Scientific Committee on Consumer Safety (SCCS). Opinion on Hydroxyapatite (nano). SCCS/1648/22. Adopted 21–22 March 2023.
(3)Scientific Committee on Consumer Safety (SCCS). Opinion on Hydroxyapatite (nano) — Submission IV. SCCS/1677/25. Adopted 26 June 2025.
(4)Shi Q, Sun L, Gao J, et al. Effects of sodium lauryl sulfate and postbiotic toothpaste on oral microecology. J Oral Microbiol. 2024;16(1):2372224. PubMed
(5)Min K, Glowacki AJ, Bosma ML, et al. Quantitative analysis of the effects of essential oil mouthrinses on clinical plaque microbiome. BMC Oral Health. 2024;24(1):578. PubMed