30 October 2025, WHO publishes a guideline on environmentally friendly and less invasive oral health care for preventing and managing dental caries, which serves Parties to the Minamata Convention as Information Document to phase out dental amalgam by 2034. WHO suggests the use of glass ionomer cements and resin-based composites as direct restorative materials for the treatment of dental caries and gives recommendations for the treatment of vulnerable populations and safe handling and application of resin-based composites.
The World Health Organization’s new Guideline on Environmentally Friendly and Less Invasive Oral Health Care for Preventing and Managing Dental Caries outlines how countries can reduce and eliminate the use of dental amalgam in line with the Minamata Convention. The document does not present the transition as material substitution alone but embeds the phase-out of amalgam within broader changes to caries management and health-system organization.
A key feature of the guideline is its emphasis on reducing the overall need for restorative treatment. WHO recommends that national programmes promote early detection of caries and non-invasive or minimally invasive interventions—such as fluoride approaches, sealants, resin infiltration, atraumatic restorative treatment (ART), and selective caries removal—before restorative procedures are considered. These measures are positioned as essential prerequisites for decreasing demand for amalgam, which historically has been used in high-volume restorative care.
When restorations are necessary, the guideline advises the use of mercury-free materials, primarily composite resins and various forms of glass ionomer cement. WHO notes that mercury-free direct restorative materials have improved over time in terms of biocompatibility, durability, tooth colour matching and ease of handling.
However, no single material is suitable for all clinical situations. It is therefore necessary to have a range of materials, with different options indicated in different circumstances. Both glass ionomer cements and resin-based composites are now included in the WHO Model List of Essential Medicines for use as fissure sealants or restorations.
The safety profile of glass ionomer cements and lower need for complex procedures make them a preferred option for children and older adults, as they minimize stress and reduce exposure to potentially harmful substances during oral health care. This recommendation may also apply to individuals with high caries risk, behavioural or medical complexities, multiple cavitated carious lesions or limited access to oral health care.
WHO further suggests limiting the use of resin-based fissure sealants and composites containing bisphenol A (BPA) derivatives in children, adolescents, pregnant or breastfeeding women, as these groups are more susceptible to potential endocrine effects and suggests exercising caution when using resin-based composites, including fissure sealants and restorations, in individuals with allergic conditions, as the monomers present in these products may cause sensitization
Dentists should follow occupational safety protocols for the proper handling of resin-based composites to reduce risks for oral health care professionals and patients and use effective isolation and thorough curing with appropriate light sources, and proper surface finishing or polishing techniques to minimize exposure to unpolymerized monomers during the application of resin-based composites.
WHO is now foreseeing to add following additional chapters before the final publication:
Implementation considerations
- Supply change and market availability
- Training for oral and other health professionals
- Waste management in oral health care facilities
- Preservation of ecosystems and sustainable development
Research Needs
- Monitoring of occupational exposure
- Environmental risks and sustainability
- Clinical and cost-effectiveness
Florian Schulze, Managing Director of the European Network for Environmental Medicine, contributed to the development of the WHO Guideline as member of the Guidance Development Group.
Further Information: