Does a 3T MRI cause more dental artifact than a 1.5T MRI?

It can. A 2025 study found that the magnetic field distortion around titanium and zirconia implants grew as field strength rose from 0.55 T to 1.5 T to 3.0 T. Titanium caused more distortion than zirconia at each step.

Can I wear clear aligners during an MRI?

Clear plastic aligners contain no metal, and one 3 T study used aligner wearers as its artifact-free control group. They come out in seconds, so taking them out before the scan removes any question. Tell the technologist you wear them.

Does a bonded retainer behind my teeth matter for a brain MRI?

In a 60-patient study at 1.5 T, stainless steel retainers caused artifact only in the oral cavity, not in the sinus, jaw joint, or back-of-brain areas tested. The authors said metal fixed retainers only need removal when the mouth itself is being imaged. Still list it on your screening form.

Can an MRI weaken the magnets in my overdenture?

One 3 T study found that moving magnetic attachments in and out of the scanner significantly reduced magnet force in one orientation, and the magnet-to-keeper hold also dropped. The authors recommended removing all removable magnetic dentures before an MRI. Ask your dentist to check the attachments afterward.

Who decides whether my braces need to come off before a scan?

The radiologist and MRI team decide based on the body part and the sequences they need. If removal is needed, your orthodontist takes the brackets off and puts them back later. Asking early gives time to book that visit before the scan date.

Can You Have an MRI With Dental Implants, Braces, or a Retainer?

The short answer: Yes, most people with dental implants, fillings, crowns, braces, or a fixed retainer can have an MRI. RadiologyInfo.org, run by the American College of Radiology (ACR) and the Radiological Society of North America (RSNA), says fillings, braces, and retainers are usually unaffected by the magnetic field. The bigger issue is image quality, because metal near the mouth can blur scans of the face, sinuses, neck, or brain. Magnetic denture attachments are the main exception and need a talk with the MRI team first.

What do MR Safe and MR Conditional mean for dental hardware?

The FDA sorts devices into MRI safety labels. An MR Safe device is nonmagnetic, contains no metal, does not conduct electricity, and poses no known hazards in any MR environment. An MR Conditional device can be used safely only in an MR environment that matches its conditions of safe use. The FDA adds that any device with an unknown MRI safety status should be assumed to be MR Unsafe.

That definition matters for your mouth. The ACR Manual on MR Safety (2026 edition) states that metal-containing passive devices cannot be MR Safe, only MR Conditional or MR Unsafe. A titanium implant, a steel bracket, and a gold crown are all passive devices with metal. So the useful question is which conditions apply to your hardware.

The FDA also notes that an implanted device degrades the quality of the MR image, which can make a scan uninformative. That second risk, image quality, is the one most dental work raises. For the wider list of implants and hazards, see our MRI safety guide.

Are titanium implants, fillings, and crowns a problem in the scanner?

For safety, usually not. RadiologyInfo.org lists dental fillings as usually unaffected by the magnetic field, with one caveat: they may distort images of the facial area or brain. The main question is how much of the image near your teeth stays readable.

That depends on the material. A 2025 study in Dentomaxillofacial Radiology compared titanium and zirconia implants. Titanium distorted the magnetic field more than zirconia. The distortion grew with field strength, from 0.55 T to 1.5 T to 3.0 T. In a volunteer, artifacts appeared mainly as signal voids in the tooth crowns close to the implants.

Crowns vary too. A 2022 study in Scientific Reports scanned crowns on a cadaver head at 1.5 T. Resin, ceramic, zirconia, and precious metal-ceramic crowns barely produced artifacts. Pure titanium and nonprecious metal-ceramic crowns created significant artifacts. If your scan covers the jaw, sinuses, or face, your dentist's records can tell you what your crowns are made of.

Do fixed braces or a permanent retainer have to come off?

Often they can stay on. The answer depends on which part of the body is being scanned. RadiologyInfo.org says orthodontic braces and retainers are usually unaffected by the magnetic field but may distort images of the face or brain.

Three studies show why the answer changes by body part:

Brain scans. A 2025 study in Clinical Oral Investigations scanned one adult volunteer at 1.5 T and 3 T. With stainless steel brackets and a nickel-titanium wire, with or without steel molar bands, all brain structures kept high diagnostic quality. Adding a steel wire across the palate caused extra artifacts, mostly on SWI and DWI sequences. The authors concluded that full removal is not needed for brain MRI.
Neck and sinus scans. A 2017 case-control study compared 80 people at 3 T, including 20 who wore clear aligners. Stainless steel brackets hurt image quality in the neck, paranasal sinuses, head and neck region, and cervical spine. They did not affect brain or jaw joint images.
Mouth scans. A 2015 study in the European Journal of Orthodontics tested 60 patients at 1.5 T, with each attachment held in a wax jig. Stainless steel brackets made every area studied impossible to interpret. Titanium brackets, ceramic brackets with metal slots, and stainless steel retainers caused artifact in the oral cavity only, in 20%, 16.65%, and 86.65% of subjects.

These studies used different scanners, sequences, and setups, so their results on steel brackets do not line up perfectly. The 2015 authors said metal fixed retainers only need removal when the oral cavity itself is being imaged. The 2017 authors advised removing steel brackets before neck, sinus, and cervical spine scans, but not for brain or jaw joint scans.

Removal has costs. The 2025 team noted that leaving appliances in place can lower the injury risk of removal and speed up imaging, which matters most in emergencies. The radiologist makes the call, so ask before you book an orthodontist visit.

What should you do with a removable retainer or denture?

Take it out before the scan. The ACR manual says anyone having an MR procedure must remove all readily removable metallic personal belongings and devices. A retainer with a wire, or a partial denture with metal clasps or a metal frame, comes out in seconds.

Clear plastic aligners and all-acrylic dentures contain no metal. Bring a case for them anyway. Taking an appliance out removes any doubt about artifacts, and the technologist does not have to guess what it is made of.

Why are magnetic denture attachments a special case?

Some overdentures snap into place with small magnets. A metal keeper sits on a tooth root or implant, and a magnet sits inside the denture. These parts are built to respond to magnetism, so the MRI team needs to know about them.

A 2015 study tested magnetic dental attachments in a 3 T scanner using American Society for Testing and Materials methods. Heating was minimal, with a top rise of 1.42 °C. But the magnetically induced deflection forces tended to exceed acceptable limits. The authors advised checking attachments before and after MRI and removing large prostheses that contain cast magnetic alloy.

A 2017 study moved magnetic attachments in and out of a 3 T scanner 15 times. In one orientation, the magnet's force dropped significantly, and so did the hold between magnet and keeper. The authors recommended removing all removable magnetic dentures before an MRI.

The keeper is fixed to a root or implant, so it stays in during the scan. An earlier study of keeper forces concluded that the risk of injury from displacement is minimal if keepers are properly attached. List every keeper on your screening form, and have your dentist check the attachments afterward.

What should you tell the MRI team before your scan?

Tell them about everything in your mouth, even work that seems minor. The ACR manual calls for a written or electronic screening form. Every question needs a yes or no answer, and both you and a staff member sign it. RadiologyInfo.org asks patients to give the device name and manufacturer to the technologist before the exam.

Dental implants, and the brand if your dentist has it on file.
Crowns or bridges, and whether they are metal, porcelain fused to metal, or zirconia.
Fixed braces, including any wire across the roof of your mouth.
A bonded retainer behind your teeth.
Removable retainers, partial dentures, or full dentures.
Magnetic attachments or keepers.

Also confirm which body part is being scanned. A brain MRI and a sinus MRI have very different tolerance for artifact from the mouth. If this is your first scan, our guide on what to expect at your first MRI walks through the visit. Tattoos raise separate questions, covered in MRI with tattoos.

The bottom line

Dental implants, fillings, crowns, braces, and fixed retainers rarely stop an MRI. The trade-off is image quality near the mouth, and that depends on the metal and the body part. Take out anything removable. Flag magnetic attachments early, since studies show strong deflection forces on them and weakened magnets afterward. Give the MRI team a full list, and let the radiologist decide what needs to come off.

If you are still sorting out the symptom that led to the scan, symptom.md explains common symptoms and when to see a doctor.

Last updated: September 2026. This article is for informational purposes only and does not constitute medical advice. Talk with your radiologist, dentist, or orthodontist about your specific dental hardware before your scan.