Jaw Expansion in Orthodontics
Posted on 07/11/2018

JAW EXPANSION: The Answer to Crowded Teeth?                                                                                                                  By Adam J. Weiss, DMD

Jaw expansion, or widening of the maxilla and/or mandible has become common occurrence in children 7-10 years old. Why is it that so many kids of this age are having this type of treatment recommended?  Is it really necessary?  What is trying to be accomplished? The purpose of this article is to shed some light on this treatment approach in orthodontics.

       Jaw expansion appliances have been around for at least 60 years. Their use rose on a renewed emphasis on treating patients without the removal of permanent teeth. Throughout the 1950’s, 60’s, and 70’s, the majority of orthodontic patients with crowding were treated with permanent tooth extractions, usually the four first premolars. A re-evaluation of this approach led many orthodontists away from this means of treatment when possible. This is not to imply that all patients can be treated without extractions. What expansion therapy has done, however, is to significantly reduce the percentage of patients recommended for extractions by the orthodontist. The orthodontist identifies these crowding problems early and starts the patient on an initial phase of expansion therapy when there are still baby teeth present (usually 7-10 years old).

      Expansion of the maxilla is possible because the maxilla is actually two bones that meet in the middle of the roof of the mouth. The line along which they meet is known as a suture.  Jaw expansion works by opening the suture thereby widening the maxilla. Widening the maxilla creates more space which helps with crowding problems.  This treatment will also correct crossbites due to a constricted maxillary arch. There are several acceptable appliance designs to achieve this expansion. This procedure is most successful and predictable in young growing patients (7-10 years old).  The maxillary suture is fused in adults, making jaw expansion in adults much more complicated.

       Expansion of the lower jaw, or mandible, works differently as there is no suture to open.  Expansion in the mandible works by expanding the teeth and bone that support them gradually over a few months. Expansion in the mandible also creates space to relieve a crowded arch.

     The latest use of arch expansion is to help with those patients that suffer from sleep disordered breathing such as snoring or sleep apnea.  Studies are showing that arch expansion can help the airway in patients suffering with obstructed or interrupted breathing.  These patients will also be evaluated for removal of enlarged tonsils and/or adenoids.  A history of snoring can now be a determining factor to place a child into expansion treatment.  More studies are needed to see whether this is a reliable treatment for sleep disordered breathing, and whether the benefit will carry into adulthood.

            Expansion therapy has changed dramatically the way in which many orthodontic patients are treated today as compared to when their parents were of similar age. While it does involve getting started before the loss of all the baby teeth, it has been shown in many instances to create the space needed for patients with crowding, and to improve breathing issues. For most parents, especially those unhappy that they had permanent teeth removed for orthodontic treatment, it is worthwhile if it means avoiding extractions. For those severely crowded cases, extraction of permanent teeth may still be necessary even after a round with expansion therapy.  A thorough discussion with an orthodontist and your family dentist is always recommended before initiating any treatment.  

            Adam J. Weiss, DMD, is a member of the American Association of Orthodontists with a practice located in King of Prussia and Collegeville, Pa.  He is also a member of the American Academy of Dental Sleep Medicine.