Phasing-down the Use of Dental Amalgam

Mercury is a toxic substance and a global pollutant that poses adverse effects to human health and the environment. It is one of the top 10 chemicals of major public health concern according to WHO. Mercury pollution exposes people and wildlife, regardless of proximity to source, to harmful effects.

Dental amalgam is a restorative material used to fill cavities caused by dental caries (tooth decay). Dental amalgam is a common filling material that has been a mainstay of dental restorative care around the world for over 175 years due to its ease of placement, material strength, longevity and cost-effectiveness. It is composed of a mixture of metals, consisting of elemental mercury (~50%) and a powdered alloy composed of silver, tin, and copper.  Mercury pollution may occur during the amalgam life cycle from production, supply, cavity placement, removal of fillings and disposal. Estimates suggest 30 to 40 per cent of mercury in amalgam enters solid waste streams, accumulates in water, soil and the atmosphere without breaking down. In this context, promoting the environmentally sound management of dental amalgam waste alongside prevention is key to reduce risks to human health and the environment. Furthermore, estimates suggest that between 3,000 to 5,000 metric tons of mercury are stored in the mouths of people worldwide in the form of dental amalgam, making the waste amalgam created by the dental industry a global issue.

A shift away from the restorative model and use of dental amalgam is now becoming a reality, underpinned by the Minamata Convention on Mercury.

Parties to the Convention are required to implement several measures to phase down the use of dental amalgam according to Article 4, Annex A, Part II of the Convention which was amended in 2022 at the fourth meeting of the Conference of the Parties, COP-4.

COP-5, in 2023, concluded to amend Annex A, Part II of the Convention with a new measure to be taken by Parties which have not phased out use of dental amalgam yet. The amendment includes more specifically the development of a national action plan or a report with respect to progress they have made or are making to phase down or phase out dental amalgam every four years. COP5 also decided to consider amending both Part I and Part II of the Annex regarding dental amalgam at COP-6. Consult the amendment text.

Dental caries is the most common non-communicable disease worldwide, affecting more than 2.5 billion people, including 514 million school-aged children. Therefore, central to the phase down of dental amalgam use are efforts to strengthen public health approaches on dental caries prevention and oral health promotion, representing an important shift from the traditional restorative dental model. A renewed global focus on disease prevention would be a fundamental step towards better oral health, thereby reducing the need for restorative oral health care and fillings (including dental amalgam). Moreover, a focus on prevention and treatment of dental caries can be further supported by creating an enabling environment for the use of quality mercury-free products and minimal intervention.