Minamata four years on

Readers will be aware that The Minamata Convention on Mercury is a global treaty, signed by the UK and over one hundred countries from all over the world in October 2013, with the intention of protecting human health and the environment from the adverse effects of mercury, for example, by limiting the use of mercury from all sources, including LED light bulbs, fluorescent tubes, fertilizers, thermometers and, of course, dental amalgam. The agreement indicated that the mercury limitation would commence within four years, and Annex A part II dealt specifically with dentistry. Four years on, it might be considered useful to reflect how far along that road we have gone, given that we agreed to ‘Promote use of cost-effective and clinically effective mercury-free alternatives’.

At the time of writing, the Convention has been signed by 128 countries and ratified by 71, with Jamaica being the most recent country to ‘deposit the instrument of ratification’. The arrangements sealed within the Convention were that it would enter into force on 15 August 2017 in the ratifying countries, that being 90 days after the fiftieth ratification was received.¹ Regulation (EU) 2017/852 of the European Parliament was agreed on 17 May this year, the implication of this being that, from 1 July 2018, dental amalgam ‘shall not be used for dental treatment of deciduous teeth, of children under the age of 15 years and for pregnant or nursing women, except when deemed strictly necessary by the dental practitioner, based on the specific medical needs of the patient’. I cannot think of anything falling into that category, with the exception of allergy to a constituent of an alternative material. Some might argue that we need amalgam for the deep Class II box where isolation is difficult (but is that specific medical need?). In my view, an amalgam restoration in that situation contaminated with blood and/or saliva isn't a great result!! It is possible to isolate a cavity in such situations with a tight matrix and then place a resin composite with an RMGI sandwich extending to the exterior of the box. In this regard, on speaking with dentists from Continental Europe, it is obvious that, for increasing numbers, their experience of using amalgam is virtually nil and, indeed, the University of Nijmegen in The Netherlands abandoned the teaching of amalgam as long ago as the year 2000. I am not aware of any patients being disadvantaged as a result.