The Centers for Medicare and Medicaid Services issued guidance to state Medicaid directors on July 23, 2026, encouraging them to restrict or eliminate coverage for mercury-containing dental amalgam fillings, marking a significant shift in federal dental policy aligned with international mercury-reduction commitments.
The notification directs states to consider limiting Medicaid reimbursement for dental amalgam procedure codes D2140-D2161, which represent the standard amalgam filling techniques, while incentivizing alternatives such as resin-based composite fillings (procedure codes D2330-D2394). States can implement these restrictions without requiring a formal state plan amendment, streamlining the administrative process for adoption.
Mercury Exposure and Vulnerable Populations
Dental amalgam combines mercury with other heavy metals to create a durable filling material. The CMS guidance identifies several populations at elevated risk from mercury exposure: pregnant women, infants and young children (particularly those under age six), women attempting to conceive, individuals with diagnosed neurological conditions, and people with compromised kidney function.
HHS Secretary Robert F. Kennedy, Jr. framed the initiative in direct terms: “Mercury has no place in the mouths of our children or in modern American health care.” CMS Administrator Dr. Mehmet Oz added that “Americans should feel confident that the health care they receive is always working in their best interest.”
Federal and International Context
The CMS directive follows an earlier decision by the Indian Health Service in February 2026 to end its use of mercury-containing dental amalgam in all IHS facilities by 2027. This action positions the federal government ahead of its international commitments: as a party to the Minamata Convention on mercury, the United States committed in November 2025 to phase out dental amalgam use by 2034.
The Minamata Convention represents a global effort to reduce mercury in products and industrial processes. By encouraging state Medicaid programs to transition away from amalgam ahead of the 2034 deadline, the federal health agencies are accelerating what was already an international policy obligation.
Implementation and State Options
States retain flexibility in how they implement the guidance. They may choose to restrict coverage outright for amalgam procedure codes, establish prior-authorization requirements that effectively limit their use, or create financial incentives that steer beneficiaries toward composite fillings. The absence of a state plan amendment requirement removes a potential bureaucratic barrier to adoption, allowing states to adjust their Medicaid dental policies more quickly.
Composite resins, the alternative filling material emphasized in the CMS guidance, have become increasingly common in modern dental practice and offer comparable durability for many applications. The shift represents a recognition that safer alternatives to amalgam are readily available and clinically effective.
Implications for Medicaid Beneficiaries
For the millions of Americans covered by Medicaid, the CMS guidance could significantly alter which dental treatments are available under their insurance. The move reflects the administration’s stated priority of reassessing federal health care policies in light of potential chemical exposures and emerging alternatives.
The timing aligns with broader efforts within the HHS to examine chemical exposures in health care settings and consumer products, part of a wider agenda to identify and reduce environmental and medicinal hazards in American health care and food systems.
States are expected to review the CMS guidance and determine their own timelines and approaches to restricting amalgam coverage, though the federal encouragement and the IHS precedent suggest increasing momentum toward abandoning the mercury-based material across public health systems.