Tired of brushing your teeth?

Scientists at The School of Pharmacy and the Faculty of Dentistry have designed small particles which can adsorb to the teeth. This can potentially protect the enamel against tooth wear and caries.

The particles can unfortunately not replace tooth brushing but be an important supplement to improve the oral health.

Illustration: Colourbox

Prevention is important

Caries is a huge public health problem. Tooth wear is also an increasing problem especially among the younger part of the population. One of the causes is the increased intake of acidic drinks. Prevention is therefore of major importance.

- It has for a long time been an interest in developing drugs that can protect the teeth, says Sanko Nguyen. She has been a PhD student at the SiteDel group at the School of Pharmacy at the University of Oslo.

Nanoparticles can potentially protect the teeth from tooth wear

In her PhD thesis, Sanko has worked with phospholipid based nanoparticles. This type of nanoparticles is called liposomes. Liposomes are vesicles, small spherical entities, enclosed by a membrane.

Liposomes can be designed to resemble the body's own teeth protective structures. In the oral cavity, proteins from saliva aggregate in globular structures which adsorb to the dental enamel. This layer can protect the teeth from acid attack. In addition, the layer lubricates the surface and can protect against tooth wear. - To use liposomes as a physical barriere to protect the teeth is new, Sanko says enthusiastic.


The picture to the left shows liposomes in an aqeouos environment resembling the structure of proteins in parotis saliva (picture to the right). Photo: Gro Smistad

The nanoparticles adsorbed to the teeth

Sanko has tested how different liposomal formulations adsorbed to hydroxyapatite, a model substance of the dental enamel. In addition, she has investigated how liposomes adsorbed to real teeth. Extracted teeth were exposed to a flow mimicking the secretion of saliva. One of the major problems when delivering drugs to the oral cavity is that saliva will wash the drug away. The effect of the drug is thereby reduced dramatically.

To potentially improve the properties of the liposomes, some of the liposomes were covered by the macromolecule pectin. Pectin may give rise to two effects, to increase the time the liposomes are adsorbed to the teeth as well as to increase the stability. The results revealed that liposomes covered by pectin adsorbed better to the teeth than non-covered.

There are still more investigations to be done before the small particles can be used in the preventive work of the global oral health. Sanko will continue to work on this project at The Nordic Institute of Dental Materials (NIOM).

By Marianne Hiorth
Published Feb. 1, 2012 10:56 AM