BPA and PFAS at the Dentist: Fillings, Night Guards and Floss (2026)

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1. What Is Worth Asking About

A dental visit puts a lot of plastic and chemistry near your mouth, and most of it is there for minutes. Gloves, bibs, suction tips and polishing paste come and go. The parts worth a question are the ones that stay. A filling sits in a tooth for ten or twenty years. A sealant is painted onto a child's molars. A night guard or retainer rests against your teeth in warm saliva for eight hours a night, often for years, and long, warm, wet contact is what moves the most out of a plastic. This guide runs in that order, from what stays longest to what passes quickest, and ends with the questions to bring.

2. Fillings: Silver, White and What Is in Each

A silver filling is amalgam, and the FDA puts it at about half mercury by weight, bound with silver, tin and copper. It gives off a little mercury vapor, more with grinding and gum chewing, and the most while one is placed or drilled out. In September 2020 the FDA advised seven groups to avoid it whenever possible: pregnant women, women planning a pregnancy, nursing mothers, children under six, people with neurological disease or impaired kidneys, and anyone allergic to its metals. The EU stopped using amalgam from 1 January 2025 except where strictly necessary, and in November 2025 the Minamata Convention agreed a global phase out by 2034.

Leave sound silver fillings where they are. The FDA and the American Dental Association both advise against removing an intact amalgam to prevent illness, because drilling it out releases the biggest dose it will ever give and costs healthy tooth. In a German trial of 90 people who blamed their symptoms on amalgam, complaints improved about as much without removal as with it. When one has to come out because it is cracked or decayed, ask for a rubber dam and high volume suction. In a 1997 Swedish study, removal without a dam raised mercury in blood and urine, and removal with one did not.

White fillings are composite resin, and most are built on Bis GMA, a building block made from BPA. A small amount of BPA reaches the patient, as an impurity and as the resin slowly breaks down. In an NIH study of 172 adults, BPA in saliva rose within an hour of a filling and was back to normal within eight hours, while BPA in urine stayed 43 percent higher a day later. The amounts are small next to food and short lived, and the newest 2025 review still says BPA free materials should be considered for pregnant women and children.

BPA free white fillings exist, and an independent lab has checked them. In a 2022 Charles University test run over 260 days, two standard composites, Kulzer's Charisma Classic and 3M's Filtek Ultimate, released 144 and 180 nanograms of BPA per gram. Two sold as BPA free, Kulzer's Charisma Diamond and VOCO's Admira Fusion, released about 2, roughly 60 times less but not zero. Ask which composite your dentist uses and whether a Bis GMA free one is an option. The bonding layer under a filling can carry Bis GMA too, so ask about that as well. Plain glass ionomer contains no resin at all, though it wears faster on chewing surfaces.

3. Sealants for Kids: Rinse, Then Spit

A sealant is a thin coat of resin painted into the grooves of a child's back teeth, and it is one of the best supported ways to prevent cavities in molars. It is also the same chemistry as a white filling, and brands differ widely. CDC chemists measured one sealant giving patients about 110 micrograms of BPA and another about 5.5, a twentyfold spread. In a 2016 study of 91 children, urine BPA rose the day after treatment and was back to background within two weeks.

Most of the dose comes from the thin layer on top that never fully hardens, and that layer can be removed. Wiping the cured sealant with pumice took off 93 to 95 percent of the leftover resin in a 1999 study, against 68 percent for a water spray, and a rinse and spit afterward keeps the rest from being swallowed. Ask which sealant your dentist uses and whether it is free of BPA and Bis GMA. Pulpdent sells Embrace WetBond that way, and one independent university study found no BPA released from it.

4. Night Guards and Retainers: Ask What It Is Made Of

A night guard is the plastic you spend the most time with. It sits against teeth and gums at body temperature in saliva all night, every night, and many people wear one for years. Dentists make them from a handful of materials, and they do not behave alike. Hard guards and the pink base of a classic wire retainer are usually acrylic. Clear retainers and aligners are sheets of PETG, copolyester, polypropylene or polyurethane, heated and vacuum formed over a model of your teeth. A growing number are milled from a solid block or printed from a liquid resin.

The one with a clear BPA finding is polycarbonate, a plastic made from BPA. In a 2024 lab study, four milled splint materials, three of them polycarbonate, all released BPA within 24 hours in water at body temperature, and scaled to a whole splint the authors put a day's release above Europe's tolerable daily intake. The common clear sheets did far better. In a 2023 study that held six of them at body temperature for eight weeks, Duran, Zendura FLX, Zendura A, Essix C+ and Taglus came in at or under the detection limit for BPA. Invisalign's SmartTrack showed a trace of BPA and a measurable amount of BPS, a close relative.

Acrylic that sets at room temperature, called cold cured or self cure, gives off its leftover building block, methyl methacrylate. In people wearing new cold cured plates it showed up in saliva for up to a week, and the researchers advised soaking the appliance in water for 24 hours before first wear. A 2024 study found 12 hours in water removed the effect of its extracts on living cells. Heat cured acrylic carries far less. Printed guards depend on finishing: in a 2023 study, unpolished printed resin killed the cells grown on it, while polished pieces behaved like milled acrylic.

Keep any guard or retainer away from heat. Align tells wearers of its Vivera retainers to avoid hot water and any heat source, and that advice holds for every one of these plastics, because heat moves chemicals out of a polymer faster than anything else. No dishwasher, no boiling to clean it, and no sunny dashboard. Replace one that has gone cloudy, cracked or rough: in lab studies of clear aligners, the number of microplastic particles they shed rose with wear. If you wear aligners, most of the BPA measured in wearers came from the tooth colored bumps bonded to the teeth, not from the trays, so the filling question above applies to those as well.

Store bought night guards

A drugstore guard costs a fraction of a custom one, and many people start there. We checked five of the best sellers, and none earned a pick. Every one is a plastic held in saliva all night with no lab test behind it. Two are softened in boiling or microwaved water and then bitten while warm, one has flavor compounded into the plastic, and one will not say what plastic it is. A guard your dentist makes in a named material, and that you soak before first wear, is the better route.

5. Cleaning a Guard or Retainer

Rinse it in cool water when it comes out, brush it gently with a soft brush, and let it dry in an open case. For a deeper clean, a short soak works, and here the product matters. Most retainer and denture tablets get their fizz and bleaching power from a persulfate. In 2008 the FDA linked persulfate to allergic reactions in denture cleansers, citing at least 73 adverse event reports, with symptoms from gum irritation and hives to breathing problems and low blood pressure, sometimes after years of use. It asked makers to warn on the label and to consider alternatives. Residue that is not rinsed off goes back into your mouth for the night.

Align's own cleaning crystals avoid persulfate. The original Invisalign Cleaning Crystals list five ingredients with no dye or flavor, one of them a chlorine releasing salt, and Cleaning Crystals+ Mint use a peroxide instead and name their mint oil. Use either for the 15 minutes the box gives, then rinse, rather than leaving a guard in overnight. A 2026 review of 43 studies found long exposure to bleach and peroxide roughens clear retainers, and rough plastic sheds more.

TOP PICK · $$

Invisalign Cleaning Crystals

Dry crystals in single use sachets. Five named ingredients: sodium sulfate, sodium carbonate, sodium tripolyphosphate, a chlorine releasing salt and SLS. No persulfate, dye or flavor. Fifteen minute soak.

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$$ · MINT

Invisalign Cleaning Crystals+ Mint

Dry crystals in a plastic bottle, one capful per soak. Sodium bicarbonate, sodium percarbonate, named mint oil, SLS and saccharin. No persulfate or dye. Fifteen minute soak.

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6. During the Cleaning: Floss, Paste and Varnish

Floss is the one chairside item you can swap in a second. The classic Oral-B Glide was coated in PTFE, the Teflon PFAS, and our floss guide covers the testing behind that. Oral-B says the new Glide is made without it, though no independent lab has retested it, and PTFE floss is still sold to dental offices in bulk dispenser refills under other names. Hand the hygienist a spool of silk, or ask them to skip flossing for the visit. Our three picks are silk coated in plant wax, free of PFAS and of plastic.

TOP PICK · $$

Hemli Home Peace Silk Floss

Peace silk coated in candelilla plant wax, in a refillable glass container with compostable refills. PFAS free and biodegradable. The best reviewed silk floss we found.

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$$ · STEEL DISPENSER

TreeBird Pure Silk Floss

Silk waxed with candelilla, mint flavored, with a refillable stainless steel dispenser and three silk refills. PFAS free and biodegradable, a complete plastic free setup.

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$$ · GLASS JAR

Dental Lace Silk Floss

Mulberry silk coated in candelilla plant wax, in a refillable glass jar with recyclable spools. PFAS and PTFE free, biodegradable, and on the Center for Environmental Health PFAS free list.

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The gritty polishing paste is mostly pumice and glycerin, often with fluoride, a sweetener such as saccharin or xylitol, a flavor, and dyes that change with the grit. Kerr's berry Cleanic lists Red 40 and titanium dioxide. No major paste lists a plastic abrasive; the grit is pumice, perlite or silica. If you would rather skip the dye and flavor, ask for a plain one. Preventive Technologies' Nada Pumice Paste has no dye, fluoride or flavor oil, and Henry Schein's Acclean is sold unflavored and uncolored. Offices order these on request.

Fluoride varnish is painted on and sets in seconds. Most brands are built on rosin, a pine resin and a known skin allergen, with a sweetener and a flavor, and 3M's Vanish is 60 to 75 percent rosin ester. If rosin gives you a rash, ask for a rosin free treatment such as 3M's Clinpro Clear, and mention a milk allergy, because GC's MI Varnish contains a milk protein. The FDA's 2025 action on fluoride covers only the tablets and drops a child swallows, not varnish. Our toothpaste guide covers the fluoride question itself.

If you are sent home with a chlorhexidine rinse, the common Peridex is 11.6 percent alcohol with saccharin and Blue 1, and in its own trial 15 percent of users had heavy staining at six months. Alcohol free versions exist, so ask.

7. X Rays and the Lead Apron

You may notice the lead apron is gone. The American Academy of Oral and Maxillofacial Radiology said in 2023 that thyroid collars and abdominal shields should no longer be used for dental X rays, and an ADA expert panel agreed in February 2024, pregnancy included. A modern dental X ray uses a narrow, aimed beam, and a shield can block it and force a retake. Some states still require them. Old aprons can also shed lead dust: a 2017 study found lead on the surface of 63 percent of 172 hospital shields, more on worn ones. Asking for one gains you little.

8. Crowns and Implants

A crown is either all ceramic or porcelain over a metal alloy, and the metal is the part to ask about. Nickel is the most common contact allergen, found in about one person in nine in patch testing, and some nickel chromium alloys contain beryllium. In a Norwegian test of 55 crowns, 18 percent held more lead in the alloy than the international standard allows, and up to a fifth did not match their declared composition. Ask whether yours can be all ceramic, and if it is metal, which alloy and whether it is free of nickel and beryllium. Implants are titanium or zirconia, and both perform alike over five years.

9. The Questions to Bring

Dentists hear these questions more often than they used to, and none of them is unusual. Ask the ones that apply to the visit you are walking into.

10. The Scorecard

Every product we researched for this article. A flag means an adverse finding on that check, not a safety violation.

11. Frequently Asked Questions