Rapid Maxillary Expansion Appliance (RME)



A rapid maxillary expander (RME) is designed to widen the upper jaw.  It is commonly used to correct posterior crossbites (narrow upper arch) by expanding the upper jaw to create a correct width in relation to the lower jaw.  The appliance consists of a metal frame which is fixed in place to several back teeth in the upper jaw.  It is used to expand the upper jaw by pushing the two halves of the arch apart, resulting in widening of the jawbone itself.  This appliance will only work if the upper jaw suture (join in the bone) is not fused.  Generally, the suture starts to fuse at around the age of 15 years old.  If the suture is fused, a surgical procedure can be performed to reopen the suture if required.

During the expansion process, you will often see a large space between the upper two front teeth.  This is a good sign that the two halves of the upper jaw is separating.  The space between the two front teeth will naturally close 1 month after active expansion.  The active expansion phase generally lasts 3-5 weeks.  Once we have achieved the desired width, the RME is generally left in place for an additional 6 months to stabilise the result.  Braces are often required after this procedure.

Click here for instructions to look after your RME