Palatal Expander

Introduction

Palatal expander is an appliance that is very commonly used in young children to to develop the arches to create space for the developing teeth. Expanders work great. I have used expanders on both my daughters as I firmly believe that expansion works great to make space enough to minimize extractions of permanent teeth for the borderline cases.

What is a Palatal Expander?

It is an appliance that is removable or fixed to the upper teeth. Our practice uses a fixed expander that  uses band on the upper molars and allows clearance from the roof of the mouth.It has a screw in the middle that gets turned and the arches expand. It has been used in the Orthodontic specialty for well over 60 years.Video

Over the past couple of decades there has been a shift in orthodontics from extracting teeth to expanding the arches when there is crowding present.

How does a Palatal Expander  work?

The palate or roof of the mouth is made up of two bones joined together down the center by a junction called a “suture”. When a patient is young, this suture is made up of stretchable cartilage that is the area where growth takes place (a “growth plate”). After skeletal maturation somewhere between 12 and 16 years of age, this suture fuses and the palate becomes a single solid structure. Expanders take advantage of the presence of the growth plate if they are used before it is fused. The palatal expander is cemented in the mouth by utilizing the molar bands. The screw is turned and the palatal bones distract from each other ( this process is called distraction osteogenesis). One sign that the expander has actually moved the two halves of the palate apart is the appearance of a space between the front teeth. The upper front two teeth are located on different sides of the growth plate and they spread apart as the palate is expanded. The result is a visible gap between the teeth. This gap is normal and desirable. In some cases the space does not appear because the teeth crowding start to unravel.

After the expander has provided the desired amount of expansion, we will typically leave the expander in place for 4-6 months holding the two halves of the palate apart while new bone develops between them.

What we typically see is that with adequate upper expansion the lower arch typically widens in response,   as the upper teeth are no longer constraining the lower teeth and the tongue applies pressure on the inside of the lower teeth to widen the lower arch.

Why is the Orthodontist recommending the palatal expander?

There are many reasons why the expander is recommended. Basic reason is that the upper jaw size is smaller than all the permanent teeth that are developing. By widening the jaw the jaw size and tooth size discrepancy can be addressed or improved.Video

Expansion  will minimize future problems of teeth moving into ectopic positions as they develop or erupt.

Some of the clinical condition where we recommend expanders are below:

  • Narrow upper arch with back crossbite
  • Narrow upper arch with front crossbite
  • Not enough space for the permanent teeth that are already erupted
  • Not enough space for the developing permanent teeth and the case can be a borderline extraction case in the future.
  • The developing cuspids are migrating too far forward due to lack of space due to narrow upper jaw

How long does the Palatal Expander stay cemented in the mouth?

Typically between 4-7 months. After the turning is completed the expander is left in place so that bone can form in the distracted width. The expander holds the width as bone forms.

Will I need braces along with the Palatal expander?

This is very case dependent. Below are some of the case where Phase I braces are indicated:

  • When permanent teeth are blocked out and they need to be brought into correct position so that the bone and gum tissue can be more normal we apply phase I braces. Braces can move teeth and hence bring the ectopic teeth in the improved position.
  • When space needs to be re-allocated for the developing permanent teeth so that they can future teeth can erupt into the right spot. Braces move teeth and hence can reallocate and create space

Will I need a full set of braces in the future?

More than likely yes. When all the permanent teeth erupt, they will not be in correct position or bite and second phase of braces will correct the alignment and bite. Once the phase I is over we will continue to monitor growth and eruption pattern to ensure that phase II treatment is timed optimally.