Interview: Restorative dentistry has become a two-class system

 

In your presentation, you argued that most modern dental materials are characterised by cosmetic rather than functional aspects. Where do they lack most in your opinion?
Prof. John Nicholson: They lack ease of use. This applies especially to composite resins. Being non-adhesive, composites have to be employed in association with bonding agents. The function of bonding agents is to alter the nature of the freshly cut tooth surface from hydrophilic to hydrophobic, and this requires careful deployment of sensitive materials in accordance with manufacturer’s instructions. Having created a surface for bonding, the composite itself must be placed. This typically requires placement in increments, with sufficient application of the curing lamp to ensure depth of cure.

All of this manipulation is difficult and requires a high level of skill on the part of the dentist. Done correctly, it works well and the resulting repair is durable and aesthetic. However, it is too complicated to be the basis of tooth repair in poorer countries, owing to the high numbers of patients, unreliable electricity supplies and fewer skilled dentists.

Most technologies seem to become cheaper over time, except dental materials. What are the reasons for this reverse trend?
In dentistry, we have emphasised appearance over performance, a feature that is not so much of a problem in countries with large numbers of dentists able to replace worn-out restorations, that is in richer communities in the developed world. The dental market therefore does not favour cheaper solutions, or simpler ones.

With state-of-the-art dental materials only affordable in rich countries and a select few in poor countries, has modern restorative dentistry become a two-class system?
It has indeed, and that two-class system applies in richer countries too, where poorer individuals are less likely to be able to afford the best-looking repair materials. Specifically, this means amalgam repairs rather than composites.

Atraumatic restorative treatment was originally developed to provide a cost-effective treatment for patients in the world’s poorest countries. What have been the experiences with the technique so far, and can it offer an alternative for a population with no access to modern dental materials?
Reports over the last few years have shown it to be very successful. A variety of patient groups, including children, young adults and even older patients, are benefiting from what is effectively minimal intervention, low-cost dental treatment. Furthermore, the performance of the glass ionomer repair materials in the atraumatic restorative treatment technique is proving to be better than what might be expected on the basis of in vitro studies of the materials’ properties.

Amalgam is still widely used, particularly in poorer countries. Are we prepared for amalgam-free dentistry, and what should be done to ensure there are proper alternatives after the phase-down has been completed?
I think we need to maintain the use of glass ionomers and perhaps see how these materials can be improved for this large and important group of patients. We also need to recognise that acquiring a proper understanding of the clinical performance of any material is a time-consuming process and that it can take years to obtain a full picture of how materials really behave in patients.

Should there be greater emphasis on the issue of dental materials in oral health campaigns and agendas around the world?
Yes, there should. We know that caries is the most widespread disease in humans, so we can a safely assume that damage to teeth is equally widespread. Consequently, in my opinion, we should emphasise the role of appropriate repair materials just as much as we currently emphasise preventative steps.

Thank you very much for the interview.