For decades, oral healthcare has been focused on the effects of fluoride and how it prevents enamel demineralisation caused by acidic food, drink and plaque because it helps to reinforce and strengthen enamel.
This is because when fluoride interacts with enamel hydroxyapatite, it results in fluorapatite, which is less soluble and more mechanically resistant.
Indeed, much scientific evidence supports the positive effect that fluoride has on oral health, and subsequently a lot of oral care products containing fluoride have been patented. In some countries, drinking water has also been enriched with fluoride.
However, fluoride is not essential for human growth and its content in the body is not under physiological control. Once absorbed, for example, fluoride is rapidly distributed throughout the body and is retained only in calcified tissues. As a result, dangerous health conditions have been linked to the daily intake of fluoride and many studies have proven that there are actually high risks associated with fluoride, in particular for children (fluorosis) and for old people (bone disease).
Despite these findings, fluoride continues to be widely used in oral care products to prevent enamel surface demineralisation.
Hydroxyapatite
Hydroxyapatite has many excellent properties, such as being able to bond directly to bone, and is widely considered to be the main synthetic biomaterial of bone filler and bone substitute in surgery.
Recently there have been exciting new developments regarding biomimetic hydroxyapatite microparticles. These new hydroxyapatite microparticles mimic natural hydroxyapatite in composition, structure and morphology, they are also surface nanostructured. This means that they have a high level of chemical reactivity and biological activity, which allows them to bind chemically to enamel and dentine apatite, thereby producing a protective biomimetic coating on the enamel surface. This enamel coating prevents the demineralisation of teeth, fights the build-up of plaque and seals dentine tubules to cancel out hypersensitivity.
Unlike fluoride remineralisation, which is based mainly on surface enamel apatite modification, the biomimetic hydroxyapatite remineralisation forms a new coating that fills in scratches on the surface of teeth, covers the enamel structure and safeguards the enamel against attacks from acid and bacteria.
This new mineral apatite deposition represents not only an innovative approach to enamel demineralisation, but also the first real enamel remineralising and repairing process.
Author
Norberto Roveri
Professor Roveri has been studying the structure and stability of fibrous proteins, and the chemical mechanism behind the formation of inorganic deposits in calcified biological tissues since 1972. He applies the experience acquired through the study of biomineralisation processes to conduct research into the use of polymer matrices to nucleate and strengthen inorganic crystals in biological and environmental applications. Norberto’s research activities mainly focus on the planning, synthesis and identification of the chemical-physical/reactivity characteristics of inorganic and inorganic-polymeric biomaterials. He focuses on innovative applications and potentialities in the orthopaedic and dental fields and in maxillofacial and cardiovascular surgery. His research is characterised by biomimetic, nanotechnological and supramolecular studies, currently aimed at analysing the surface activities of inorganic nanocrystals capable of releasing biologically active molecules through controlled kinetics and of interacting selectively with the biological environment. At the same time, Prof. Roveri applies his skills and know-how to develop geomimetic inorganic nanotubes with important applications in both the technological and environmental fields concerning issues linked with the toxicity of asbestos and atmospheric particulate matter. Recently Prof. Roveri has also studied the characterisation of atmospheric particulate matter, paying particular attention to its inorganic and fibrous components and to its chemical relations with the biological systems responsible for its toxicity. Prof. Roveri has published the results of his research projects in a number of specialist international journals and has spoken at numerous national and international conferences. Professor Roberto Noveri developed BioRepair toothpaste with Coswell R&D at the University of Bologna in 2006.