The environmental impact of dental amalgam and resin-based composite materials

Key Points

  • An overview of commonly used dental materials and the impacts of their use on the environment is presented.

  • Environmental pollution pathways are considered for both amalgam and resin-based composite.

  • Microplastic pollution from dental resin-based composite applications is highlighted.


Direct-placement dental restorative materials include dental amalgam, glass ionomer, resin-modified glass ionomer, compomer and resin-based composite (RBC). The choice of restorative material is determined by its ability to restore the structure and/or the aesthetic appearance of the dentition and to impart a net therapeutic value. In this way, the most appropriate material system is chosen to manage each particular clinical situation in the most effective manner. The most commonly used direct-placement materials in everyday modern dentistry are dental amalgam and resin-based composites. To date, concerns about the environmental impact from the use of dental materials has focused on dental amalgam and mercury release. It is now evident that the continued use of dental amalgam is time-limited on the basis of environmental pollution as recommended by the Minamata Treaty. The recommendations include a planned phase-down of use of dental amalgam with an anticipated complete phase-out by 2030. The environmental impact of other restorative dental materials deserves further consideration. This article provides a detailed overview of the environmental issues associated with the use of dental amalgam, the potential environmental issues associated with the alternative resin-based composite restorative materials and to consider recommendations for further research.

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The authors gratefully acknowledge the financial support received from the Shirley Glasstone Hughes Trust Fund in the form of a research grant that has enabled the production of this paper and ongoing work by the research team into this field.

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Correspondence to S. Mulligan.

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Mulligan, S., Kakonyi, G., Moharamzadeh, K. et al. The environmental impact of dental amalgam and resin-based composite materials. Br Dent J 224, 542–548 (2018).

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