Composite vs Amalgam in 2026: Why the 'Dead' Debate Just Got Resurrected

Three major insurance carriers quietly updated their composite reimbursement schedules this fall, and suddenly the amalgam debate—which many assumed was settled—is roaring back to life. While most practitioners thought we'd moved past the composite vs amalgam discussion, new evidence on secondary caries rates and an unexpected regulatory development in the EU have dentists questioning everything they thought they knew about posterior restorations.

The timing couldn't be more awkward. Just as composite materials seemed to have finally proven their worth, a comprehensive meta-analysis published in the Journal of Dental Research this summer delivered some uncomfortable truths about long-term performance that nobody wanted to hear.

The Longevity Reality Check

Dr. Michael Harrison, a prosthodontist at the University of Michigan who's been tracking restoration outcomes for two decades, doesn't mince words about what the latest data reveals. "We've been telling patients that modern composites last just as long as amalgam, but that's simply not supported by the 15-year follow-up studies we're seeing now," he says. "The gap is smaller than it used to be, but it's still there."

The numbers are sobering. While amalgam restorations show a 94% survival rate at 10 years, Class II composite restorations clock in at 87%—a difference that translates to real chair time and patient frustration. More concerning is the secondary caries picture: composite restorations develop recurrent decay at nearly twice the rate of their amalgam counterparts (12% vs 6.8% over 10 years).

But here's where it gets interesting. The same studies show that when you factor in aesthetic considerations and patient satisfaction scores, the overall "success" metrics flip. Patients consistently rate composite restorations higher, even when they require more frequent replacement.

"We've been telling patients that modern composites last just as long as amalgam, but that's simply not supported by the 15-year follow-up studies we're seeing now."

The European Catalyst

What's really stirring the pot is the European Union's announcement that they're accelerating their mercury phase-out timeline. Originally planned for 2030, the complete ban on dental amalgam will now take effect in January 2028—and early reports suggest similar regulatory pressure is building in several US states.

"The writing's on the wall," says Dr. Patricia Kowalski, who heads the restorative department at Northwestern University's dental school. "Whether we think the science supports it or not, the political momentum is undeniable. We need to be having honest conversations about what this means for patient care."

The regulatory push isn't just about mercury safety—it's about environmental impact. The EU's decision was heavily influenced by new data showing that dental amalgam contributes approximately 40% of mercury emissions in wastewater treatment plants, a figure that surprised even environmental advocates.

Technique Still Matters More Than Material

Here's what might be the most important finding buried in all this data: operator technique accounts for more variation in restoration longevity than material choice. The top-performing composite restorations in recent studies consistently came from practices that had invested heavily in isolation protocols, adhesive system training, and incremental placement techniques.

3M's Filtek Supreme Ultra and Dentsply Sirona's SDR Flow have shown particularly impressive results when placed with strict moisture control, but even these premium materials fail predictably when isolation is compromised. The message is clear—switching from amalgam to composite isn't just about swapping materials; it's about upgrading your entire approach to posterior restorations.

Interestingly, practices using rubber dam isolation for all posterior composite work report secondary caries rates that nearly match amalgam performance. The catch? Only about 23% of general practitioners routinely use rubber dams for Class II composites, according to recent ADA survey data.

The Insurance Variable Nobody's Talking About

While everyone focuses on clinical outcomes, the economics are shifting in ways that might ultimately decide this debate. Delta Dental's recent decision to reimburse composite restorations at 100% of their allowable fee (matching amalgam coverage) represents a seismic shift in how insurers view these materials.

But there's a catch that practices are just starting to discover: the increased reimbursement comes with enhanced utilization review. Claims data suggests insurers are scrutinizing composite longevity more closely than ever, with some carriers implementing "frequent replacement" flags that could impact future coverage decisions.

Looking Ahead: The Hybrid Reality

The most pragmatic practitioners aren't choosing sides—they're developing material selection protocols based on specific clinical scenarios. Large Class II restorations in heavy grinders? Amalgam still has advantages. Moderate cavities in aesthetic zones with good isolation potential? Modern composites excel.

"We're moving toward a more nuanced approach," explains Dr. Harrison. "The question isn't which material is 'better'—it's which material is most appropriate for this specific patient, in this specific tooth, placed by this specific practitioner."

The reality in 2026 is that both materials have evolved significantly. Amalgam formulations now incorporate copper more efficiently, reducing corrosion and improving longevity. Meanwhile, composite chemistry has advanced to include stress-reducing monomers and improved filler technology that addresses many traditional weaknesses.

The Path Forward

What's emerging is a more sophisticated understanding of material selection that goes beyond simple either-or decisions. The practices thriving in this environment are those that have invested in proper training, equipment, and protocols to make composite restorations work reliably—while maintaining the skills and materials to place amalgam when clinically indicated.

The debate isn't dying; it's maturing. And that maturity might finally give us the nuanced, evidence-based approach to posterior restorations that our patients deserve. Whether regulatory pressure accelerates this evolution or forces uncomfortable compromises remains the biggest unknown as we head into 2027.