Types of Dental Fillings: Amalgam, Composite, Ceramic, Gold & More

My dentist still has patients with silver fillings from the 1970s, still holding strong, still occasionally sparking a conversation about whether they’re secretly dangerous. They aren’t, though the question comes up often enough that it’s worth actually answering properly, along with everything that’s replaced amalgam since.

Types of dental fillings used to mean one real choice. Now it means five, each solving a slightly different problem.

Five Materials, One Job: What Dentists Actually Use for Fillings

Five materials cover almost every filling done today, per the ADA’s own list: composite resin, amalgam, gold, ceramic, glass ionomer. Cleveland Clinic groups them differently, into direct fillings, which get shaped in your mouth on the spot, and indirect ones, which come back from a lab.

What decides which one you actually get isn’t preference; it’s the tooth itself. Where it sits, how big the cavity is, how much force it takes when you bite down, and budget too. Nothing on this list wins outright.

What Is Amalgam, and Is the Mercury Actually a Concern

Amalgam is roughly half liquid mercury by weight, mixed with a powdered alloy of silver, tin, and copper, according to the FDA’s patient information on dental amalgam. That mercury content is exactly why this material generates more questions than any other of the types of dental fillings covered here.

The FDA’s actual position, reaffirmed as recently as 2020, is that dental amalgam is safe for the general population. The ADA backs this directly too, stating that existing evidence shows amalgam is not harmful to most patients. There’s a real caveat attached, though. The FDA specifically flags pregnant women, nursing mothers, young children, and people with existing neurological or kidney conditions as groups who should discuss avoiding amalgam with their dentist, out of caution rather than confirmed harm.

One thing both agencies agree on firmly: don’t remove an existing amalgam filling that’s in good condition just out of worry. The FDA notes that removal itself causes a temporary spike in mercury vapor exposure, which makes pulling out a perfectly fine filling arguably riskier than just leaving it alone.

What Is Composite Resin? Why Is It So Common Now

Composite has become the default for a lot of dentists, made from a resin base mixed with powdered glass or quartz. It bonds directly to the tooth structure, which brings a real advantage amalgam never had, less of the original tooth needs to be removed to place it.

Color match is the obvious selling point, blending in close enough to natural enamel that most people can’t spot it in conversation. It’s not without tradeoffs, though. Composite wears down faster than amalgam under heavy chewing, and it can pick up staining over the years from coffee, wine, or tobacco in a way amalgam simply doesn’t, one of the tradeoffs worth knowing before choosing between the types of dental fillings available for a visible tooth.

What Is Glass Ionomer Used For

A different chemistry entirely, glass ionomer forms from a mix of acrylic and a specific type of glass. It bonds chemically to the tooth on its own. No separate bonding agent needed. It also releases fluoride slowly over time, still working in favor of the tooth long after the filling’s placed.

Durability is where it falls short compared to composite or amalgam. It wears down faster under real chewing pressure. That’s why it shows up most in baby teeth, small cavities near the gumline, or as a temporary filling rather than something meant to survive years on a molar, one of the more situational types of dental fillings on this list.

Ceramic vs. Composite – Which Actually Holds Up Better

They look the same at first glance. Both tooth-colored, both blending into a smile. The difference is underneath. Ceramic is porcelain, made outside the mouth and cemented in, while composite gets shaped chairside in one visit.

That extra step buys real staying power. Ceramic resists staining better than composite. It holds color years longer under the same coffee and wine exposure. Cost climbs too, closer to gold than to standard composite. That’s why ceramic tends to get reserved for cases where durability and appearance both matter.

Composite and glass ionomer sit at the other end of the range. Composite wears and stains faster under regular use. Glass ionomer just was never built for heavy, long-term chewing pressure in the first place, which puts these three different types of dental fillings on a fairly clear spectrum from durable to disposable.

Why Do Some Patients Still Choose Gold

Gold fillings, technically an alloy of gold mixed with copper and other metals, remain one of the longest-lasting options available, sometimes outlasting every other material on this list by a wide margin. They’re gentle on opposing teeth too, wearing down the tooth they bite against less than most alternatives.

The obvious tradeoff is visibility. Nobody’s mistaking a gold filling for a natural tooth, and it costs meaningfully more than amalgam, sometimes several times over. It also takes two office visits rather than one, since gold fillings get fabricated outside the mouth first, similar to ceramic. Rare, but not extinct, this remains one of the types of dental fillings that still shows up for patients who value longevity enough to accept the look and the price.

Direct vs Indirect Fillings – What’s the Actual Difference

Cleveland Clinic draws this line clearly. Direct fillings, amalgam, composite, and glass ionomer among them, get placed and shaped inside your mouth in a single visit, no lab involved. Indirect fillings, like gold and most ceramic work, get fabricated outside the mouth first and then cemented in during a follow-up appointment.

That second visit isn’t a downside exactly, more a tradeoff. Indirect fillings can be shaped and finished with more precision outside the constraints of working directly inside a patient’s mouth, which partly explains why they tend to last longer and cost more.

How Do You Actually Choose Between These Materials

Location matters most. Back molars do the heavy lifting when you chew, and amalgam, gold, or a strong ceramic are built to take that kind of hit. Front teeth flip the priority toward how things look, which usually means composite or ceramic instead.

Cost plays into it too; amalgam and composite generally run cheaper than gold or ceramic. None of this has to get sorted out alone, either. A dentist can look at the tooth itself, where it sits, how much natural structure survived the decay, and weigh these tradeoffs among the different types of dental fillings with real specifics a general guide never has access to.

FAQ

Is amalgam still an option, or on its way out?

Not officially in the US. Composite’s gotten more popular for cosmetic reasons, but the FDA and ADA still consider amalgam safe and effective. Back teeth, in particular, still get it fairly often.

Can I switch from amalgam to composite for cosmetic reasons?

Yes. The FDA does advise against pulling out amalgam that’s in good shape purely for looks, since removal itself briefly raises mercury vapor exposure. Once a filling needs replacing anyway, switching materials is fair game.

Composite vs. amalgam, which one actually lasts?

Amalgam, hands down, especially anywhere that takes real chewing pressure. Composite can go the distance too, just not as far, and it depends a lot on the size of the cavity and how hard that tooth works.

Is glass ionomer meant to be permanent?

It can be, but it’s used more often for temporary fillings, baby teeth, or small cavities near the gumline. Durability under sustained chewing just isn’t its strength.

Conclusion

Five real materials, each solving a different problem. Amalgam and gold hold up best under years of chewing. Composite and ceramic blend in visually in a way metal never will. Glass ionomer plays a smaller role, gentler on young teeth and useful for a cavity that doesn’t need to survive decades of pressure.

If a dentist recommends one material over another, ask why. Usually, it comes down to where the tooth sits and how much of it is left, not a default answer that fits every one of the types of dental fillings the same way.