17 August, 2021


What is an Expander?

What is an Expander?

Orthodontic treatment is not just braces. There are many different treatment options out there today including your standard braces but also expanders, clear aligners (Invisalign), functional appliances and many others. We will focus today on expanders.

An expander is an orthodontic appliance that is used to widen the upper or lower jaw. Expanders are most often prescribed in children to widen their upper jaw (Maxillary Bone).

When are expanders needed?

As part of an early orthodontic exam your orthodontist will check for potential bite discrepancies. One common bite discrepancy is a crossbite of the back teeth. This occurs when the upper jaw is too narrow and your upper teeth bite inside of the lower back teeth. Crossbites can be bilateral (both sides) or unilateral (one side) but in either event it is advisable to use an expander to correct this discrepancy at a young age. The Maxillary bone fuses as we get older so expansion at a young age is most predictable and effective.

How do expanders work?

The most common expander is a RPE (Rapid Maxillary Expander). The expander connects to the teeth and has a jackscrew in the middle. The expander is turned at home, usually once per day, until the desired amount of expansion is achieved.

How do you turn an expander?

Turning the expander is sometimes a daunting task for parents. It really is simple once you get the hang of it, and if you have a cooperative child! In this video we demonstrate how to turn an expander.

What has changed since you had an expander?

Expanders have been around for awhile but there has been new technology incorporated. Nowadays expanders can be fabricated from a digital scan of your teeth rather than a physical impression. Also, the bands on the back teeth no longer need to go fully around and in between the teeth because the bands themselves can be 3D printed! This avoids the painful and extra step of the orthodontist placing separators between the teeth a week before expander insertion. There are also new jackscrew designs that have ‘memory’ so you do not actually have to physically turn the expander. If you child is prescribed an expander by your orthodontist do not be alarmed! This is the most commonly done early treatment (phase I) in an orthodontic office. It is simple, effective, and has long lasting positive effects. Let us know if you have any questions and have any other suggestions for future blog posts. Thank you!