Much of the hydroxyapatite literature has involved researchers with affiliations to oral care companies. That's not unusual in dental research industry-funded trials are standard practice but it does make this paper notable.

Naim and Sen, from the Department of Orthodontics at the University Hospital of Schleswig-Holstein, Germany, conducted a structured narrative review of recent clinical HAP evidence with no declared conflicts of interest and no external funding beyond an open access publication grant from their university. ^[1]

Published in September 2025 in the Journal of Functional Biomaterials, the review searched PubMed for all clinical trials on hydroxyapatite in dentistry published within the past five years. Of 42 results, 15 met the inclusion criteria — covering remineralisation, caries prevention, and dentin hypersensitivity outcomes across children and adults. ^[1] 

Their conclusions are consistent with the broader evidence base, and their independence adds a layer of credibility worth noting.

The review's strongest recommendation relates to young children. The authors note that accidental toothpaste ingestion is common in this group, that recommended fluoride dosages are frequently exceeded by parents, and that this materially increases the risk of dental fluorosis. ^[1] The paper states directly:

"In cases where swallowing of toothpaste is likely, the use of HAp instead of Fl should be preferred, particularly in young children. Due to its chemical similarity to natural bone and tooth structures, HAp demonstrates excellent biocompatibility and clinically relevant toxicity can be ruled out."

— Naim & Sen, Journal of Functional Biomaterials, 2025

This is a significant clinical recommendation from independent university researchers — not a product claim, but a direct statement of clinical preference in a context where safety is the primary concern.

One area where the review identifies a potential advantage for HAP over fluoride is in the management of molar-incisor hypomineralisation (MIH) — a condition affecting approximately 14% of children globally, characterised by defective enamel mineralisation that causes sensitivity, pain, and elevated caries risk. ^[1]

A split-mouth study included in the review found that nine months of zinc-HAP application significantly reduced both the MIH Treatment Need Index and the hypersensitivity of affected teeth. ^[1] The authors note that HAP's mechanism — depositing a mineral layer that physically occludes dentinal tubules and fills enamel defects — makes it particularly suited to hypomineralised surfaces where enamel structure is already compromised.

This review is notable for two reasons beyond its conclusions. First, it is independent — the same findings reached by research with no connection to HAP manufacturers reinforces that the evidence base is not an artefact of industry funding.

Second, it is current — with a search window to February 2025 and publication in September 2025, it captures the most recent clinical literature, including trials published in 2022, 2023, and 2024 that earlier reviews could not include.