Scientists Found Microplastics in Dental Tartar. Now I Have Questions for My Dentist.

The short answer: Scientists found 26 types of microplastics in samples of human dental tartar. Some plastic particles also damaged gum cells in laboratory experiments. We don't know exactly where the particles came from, but if you're getting dental work done, there's a good reason to ask what materials are going into your mouth. And yes, there are alternatives to conventional plastic-based fillings.

You go to the dentist, sit in that uncomfortable chair, open your mouth and let someone scrape away whatever has been building up on your teeth.

Maybe you get a filling. Maybe you spend the entire appointment wondering whether you remembered to floss this week.

What you probably aren't thinking about is plastic.

Well, apparently we should add that to the list.

There's plastic in dental tartar?

In 2025, researchers studying human dental calculus, the hardened plaque your dentist removes during a cleaning, identified 26 different types of microplastics.

The three most common were polyamide, polyethylene and polyurethane. You might recognize them from clothing, packaging and everyday plastic products.

Except this time, they were found in people's mouths.

The researchers also tested polyethylene particles on human gum cells in a laboratory. The cells showed damage, struggled to move normally and produced signals associated with inflammation.

Does that prove microplastics are causing gum disease? No. But watching plastic particles interfere with living gum cells is hardly a reason to lose interest.

And here's the particularly annoying part: we don't know exactly where the particles came from.

Food, water, toothbrushes, dental materials? All are possible sources worth investigating.

Which brings us to something I had never given much thought to.

Wait, what are fillings actually made of?

Those nice white fillings that match your teeth? They're often made from dental composite, a combination of mineral or glass fillers held together by synthetic resin.

Dentistry uses polymers for all sorts of things: fillings, retainers, dentures, clear aligners and adhesives.

And these materials don't spend their lives sitting quietly in a display cabinet. We chew with them. Grind our teeth. Drink hot coffee. Brush them twice a day.

Research has shown that resin-based dental materials can release microscopic particles during procedures such as grinding and polishing, as well as under certain laboratory wear conditions.

That doesn't mean your filling caused the plastic found in someone's tartar. But it does make me wonder why we don't talk more about what happens to dental materials as they age.

Especially when some of them stay in our mouths for years.

So, can we get fillings without plastic resin?

Turns out, we have options. They aren't interchangeable, and which one works depends on the tooth, the size of the damage and how the restoration is attached.

Gold inlays and onlays. Yes, actual gold alloys. Durable, established dental restorations, although generally more expensive and not suitable for every repair.

Ceramic or porcelain restorations. The restoration itself doesn't need a plastic resin matrix. But here's the catch: your dentist may use resin-based cement to bond it to the tooth.

Conventional glass-ionomer fillings. Another option without the typical composite-resin matrix, although they're generally less suitable for large repairs on heavily loaded teeth. And conventional glass ionomer isn't the same as resin-modified glass ionomer.

There's also traditional dental amalgam, which contains mercury rather than plastic resin. That's an entirely different materials debate, and its routine use has largely been phased out in the EU.

Suddenly choosing a filling sounds a bit more interesting than picking between white and silver.

What I'm asking at my next appointment

If I need a new filling, I'm asking:

"What is this made of, and is there a good resin-free alternative for this particular tooth?"

If ceramic or gold is an option, I'd also want to know what holds it in place.

And I'd ask what happens when the material wears down or eventually needs replacing.

None of this means ripping out perfectly functional fillings. Drilling into a tooth to replace a restoration is not exactly a harmless experiment, and the research hasn't established that replacing existing composites improves health.

But when something needs repairing anyway? I'd rather know my options before agreeing to have a material installed in my mouth for the next decade.

Honestly, I didn't expect research on dental tartar to send me down a rabbit hole of gold restorations.

But here we are.

Gold grills might be making a comeback. For scientific reasons, obviously.

Sources

• Wu, Z. et al. (2025). Polyethylene: An Identified Component of Human Dental Calculus Triggers Cytotoxicity and Inflammatory Responses in Gingival Fibroblasts. Environment International.
• Šimunović, L. et al. (2025). Micro- and Nanoplastics in Dentistry: Challenges in Obtaining High-Quality Evidence. Materials.
• American Dental Association: Materials for Direct Restorations.
• American Dental Association: Materials for Indirect Restorations.
• European Union Regulation 2024/1849: Restrictions on Dental Amalgam.