x-rays

Do Braces Make the Roots of Your Teeth Shorter?

April 17th, 2013

Do braces make the roots of your teeth shorter? How serious is root resorption? Can it be prevented or treated? These are all important questions and each orthodontic patient should be informed on the risks and limitations associated with orthodontic treatment, including root resorption. That is why we have each patient/guardian read and sign the ‘Informed Consent for the orthodontic patient’.
Braces work by creating little cramps around each tooth. The enzymes that are summoned by orthodontic forces cause old bone to dissolve where there is pressure and new bone to be formed where there is a void. These responses are normal and are the basis for orthodontic tooth movement. Research has shown that tooth movement causes at least small changes in the shape and length of the roots in ALL patients. In 98% these changes are undetectable with the naked eye.
In 1-2% of patients, however, obvious root shortening occurs during routine orthodontic treatment. These patients are just more genetically susceptible to root resorption. Root shortening can even run in families. This genetic predisposition is important and should be communicated to your orthodontist if you are aware that it has been noticed in your family.
Are there things an orthodontist can do to cause or prevent root resorption? Some have theorized that root resorption happens if the teeth are moved too quickly or too slowly. Teeth that are moved too quickly may be subject to too much force they say. However, in many cases where a patient has experienced resorption the same amount of force was used for exactly the same amount of time as patients who did not experience resorption. Braces that are on longer logically have more time to cause a problem. However, there have been transfer cases that have had braces on for more than 5 years with no signs of root change. There really is neither documented cause of nor protocol to follow to prevent this shortening.
So what can be done about root shortening during treatment? About the only thing an orthodontist can do is to monitor each patient during treatment using routine x-rays. These should be taken at least annually as long as the braces are on. If root shortening is noticed, it should be pointed out and discussed with the patient and their family. Depending upon the amount of shortening, treatment may be continued as normal, the treatment time shortened (stopping after spaces close for example), or the braces immediately removed. It is generally believed however that a tooth can lose up to half of its root length and never have a problem.
Root resorption is a normal consequence of orthodontic treatment. Hundreds of cases are treated exactly the same way without incident while a handful may experience obvious root shortening. Be sure to allow your orthodontist to take x-rays on a regular basis to monitor your progress and screen for problems during treatment. Ask her to specifically look for root shortening if she does not bring it up herself.