Can MRI and traditional work together?

This is a frequently asked question by patients or parents of children with traditional braces due to an orthodontic treatment: If an MRI is required for medical purposes, would it be possible to have it while having traditional braces in the mouth? The answer is yes, it is safe to have an MRI scan while having traditional braces in the mouth, however, depending on the area being investigated in the MRI, there may be ambiguities/alterations in the imaging due to the effect exerted by a metal orthodontic appliance.

Is it safe to have an MRI scan when using traditional braces?

Magnetic resonance imaging (MRI) is a procedure used to examine anatomical structures in our body, by taking pictures of the inside of the body. Unlike X-rays, which use ionizing radiation to locate mainly the densest parts of your body (skeletal bones), MRI scans use magnetic fields for the depiction of the soft tissues in your body.

Your doctor may refer you for an MRI scan for various reasons: muscle or ligament lesions, oncogenic processes, brain lesions, or even simply to investigate the source of any existing chronic pain.

For patients in the process of getting orthodontic treatment with traditional braces, there is an inevitable question: is it safe to perform an MRI while a patient has braces on?

The answer is yes, of course. It is absolutely safe to have an MRI scan with traditional braces in the mouth. The minimal amount of metal in your mouth from the brackets and the arch (wire) that joins them will not have a negative effect on your health during the MRI procedure.

When it comes to the effect of orthodontic appliances in MRI, the only possible problem has to do with image distortion.

Traditional metal braces distort the depiction of the head and neck in an MRI

Traditional braces do not pose a health risk during an MRI, however, there may be distortion of the imaging during diagnostics of the head and neck, i.e., anatomical structures that are in close proximity or overlap with the fixed device in place.

The metal of the brackets can distort the resonance of the MRI. In order for our reader to understand this phenomenon, we could say that there is a great resemblance to what happens with a radio and radio waves.  An MRI tunes the magnetic field to a specific frequency to get a clear image; at that time, if there is any metal element, it would have a distorting effect on this tuning process, which results in image distortion.

This is a common problem when there is any metal element in the body, such as metal artificial hip joints, metal osteosynthesis plates from a previous surgery or even metal tooth fillings, so it is not just about the metal braces used by your orthodontist during an orthodontic treatment.

For this reason, your treating physician, in consultation with your orthodontist, may decide to remove the orthodontic appliance if the MRI diagnostics involves an area that may be deformed by your metal brackets. This is valid when it comes to the brain, anterior region of the face and the eye sockets, as well as the oral cavity and the neck.

As a result, patients who have a fixed orthodontic appliance (“braces”) containing metal, such as stainless steel or titanium, may need to have the appliance removed before having an MRI scan. A study of sixty patients in 2014 concluded that stainless steel brackets should always be removed before an MRI scan of the head and neck. However, brackets are made of titanium alloy may remain, especially if the radiologist changes the scan/imaging setting to a T2 sequence. The same applies in cases where due to force majeure it is not possible to remove the metal brackets from the mouth, and at the same time there is an immediate, urgent medical need for an MRI.

In any case, there is no health risk due to a fixed orthodontic appliance and the effect of the magnetic field on them during the MRI procedure, where you enter the scanner. If you have further questions, please consult your physician.

All removable orthodontic appliances and accessories must be removed before performing an MRI

Hawley type dentures and auxiliary orthodontic appliances (rings, lingual & palatal beams, Herbst or Forsus appliances) must be removed prior to the MRI because of the metallic elements they contain and their distorting effects on imaging.

Ceramic bracket and plastic Invisalign transparent membranes do not have a negative distortion effect

In patients undergoing orthodontic treatment with Invisalign transparent membranes (hypoallergenic plastic material) or wearing ceramic brackets, the orthodontic appliance does not need to be removed before the MRI scan, because only metal elements can interfere with MRI image quality. However, to be on the safe side, you should consult your orthodontist before having your imaging.

Retaining arches for maintaining the orthodontic result and MRI

It is necessary to remove the retaining arches used to maintain the orthodontic results, which are glued to the lingual surfaces of the anterior teeth after the end of orthodontic treatment, only in cases where the diagnostic MRI concerns the oral cavity and the soft molecules that make it up or surround it. For any other diagnostic test, they can remain in the mouth. In any case, this case also asks for consultation of your treating physician with your orthodontist.

Inform your orthodontist as soon as possible

Under normal circumstances, ceasing your orthodontic intervention by removing the bracket in the middle of treatment is undesirable. This happens for two reasons: 

First, your teeth may need some time to adjust to the braces once they are repositioned. As a result, the treatment time can be extended by several months.

Secondly, repositioning always involves new brackets, not “recycling” the old ones that were removed before the MRI, so there is always an additional financial burden for this reason. This mainly concerns the use of personalized lingual device (“internal braces”) that have high laboratory costs. 

Therefore, and in any case, it is recommended that you inform your orthodontist as soon as possible. If you are aware of the necessity for an MRI scan before starting your orthodontic treatment, your orthodontist may delay the start of the intervention until the scan is carried out, or choose Invisalign transparent membranes as a treatment appliance, to allow for the uninterrupted orthodontic treatment even in cases where there is a need for repeated MRIs, at regular intervals.