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Dr. Marta Baird at Baird Orthodontics explains the purpose of maxillary skeletal expansion during orthodontic treatment. She also shows two different types of expander appliances. A traditional banded expander and the Invisalign(R) Palatal Expander.

The upper and lower jaws are called the maxilla and mandible. Beneath the gum tissue, the upper and lower jaw house all of the teeth. The upper jaw is made up of two parts, a right and a left. The lower jaw is one bone.

When I evaluate the width of the upper jaw compared to the lower jaw, I measure on an x-ray at the level of the first molar. From this view we are looking at the width of the upper and lower jaws.

In a normal bite, the upper jaw is wider than the lower jaw. This allows the teeth to fit together properly.

Between the right and left maxillae, there is an area referred to as the maxillary midline suture. In young patients, orthodontic appliances can stimulate this area to grow. The ideal age for expansion is between 8 and 9 years old. This is because expansion is very predictable and relatively comfortable at this age. As patients get older, this area starts to fuse. More and more pressure is required to expand on teen patients.

A bilateral cross bite occurs when the upper jaw is so narrow that the upper teeth fit inside of the lower teeth. This is corrected by expanding the upper jaw.

Some patients have a narrow jaw that causes them to posture to one side. This causes a cross bite on only one side as well as a mandibular asymmetry. Without early treatment, the asymmetry will become a permanent facial asymmetry. After expansion, the mandible repositions in a more symmetrical position.

Most often when the maxilla is narrow, the mandibular teeth tip inward to compensate. When the lower teeth are aligned, width deficiency because more pronounced. These patients receive an expander so that the upper and lower teeth can fit together in a functional bite.

If the narrow arch is corrected without a skeletal expander, only the teeth are moved. This can mean that the teeth are moved outside of their stable position in the bone. This can result in future dental problems such as recession.
Follow the link to our case examples.

Dr. Marta Baird describes the treatment for several patients treated at her practice, Baird Orthodontics. The treatment plans include an Expander followed by braces or Invisalign(R) treatment. Expansion is best done around age 8 when patients have a lot of growth remaining. Once all of the adult teeth come in, the suture between the right and left sides starts to fuse. By age 12, the force to expand the maxilla is much higher. Expansion is more comfortable at a younger age when less force is needed.

This patient came in for a consultation when he was 8 years old. His upper jaw was very narrow and he had a bilateral posterior cross bite.

The goal of Phase I was to expand his maxilla (upper jaw) and create space for his developing teeth. Once he had finished one year of Phase I treatment, the patient was monitored during the next phase of development.

There are 12 adult teeth present during Phase I. The observation phase monitors the eruption of 16 additional adult teeth after the first phase.

Once all of his adult teeth had erupted, the patient was ready for Phase II treatment. The patient was treated using Invisalign (R) Aligners for 15 months.

He and his family are thrilled with the result!

We love our Invisalign Stickables. They are a fun and colorful way of customizing your Invisalign aligners. There are many designs available for purchase at the Invisalign store. Dr. Baird made a video on how they are used.