Invisalign First Arch Expansion for Children: Treatment of Crowding, Crossbite, and Deep Bite

Hello.

This is Apgujeong Orthodontic Clinic.

Today’s post is also about Invisalign First for children.

24.02~25.07

If the treatment timing is right, it is possible to complete the permanent dentition occlusion.

This is a 10-year-old child who came for orthodontic treatment in January 2024.

24.02

It was said that the child had had partial anterior orthodontic treatment at a pediatric dental clinic 3 years ago.

So there was a wire retainer attached to the upper front teeth, connecting the two central incisors.

The midline is off by about 2 mm, and the long axis of the upper front teeth is tilted to one side.

A deep anterior bite, or deep overbite, is also present.

24.02

There is a crossbite due to severe crowding.

24.02

24.02

We recommended Invisalign First orthodontic treatment with the goal of arranging the crowding through arch expansion.

From February 2024 to September 2024, after wearing all 19 appliances in the first set, this is how it looked.

24.09

The midline improved, but a slight discrepancy remained, and both the crossbite and the crowding improved.

24.09

24.09

In the meantime, the one remaining baby tooth fell out and the child entered a full permanent dentition stage.

24.09

To improve the midline, we decided to make additional appliances.

From October 2024 to January 2025, after wearing all 14 additional appliances, this is how it looked.

25.01

For the additional appliances, elastics were prescribed to improve the midline, and because the child wore the elastics diligently, the midline actually shifted in the opposite direction compared with 3 months earlier.

In cases like this, if the elastics are stopped, the position will return to some extent toward the original location, so we decided to observe while using the last stage 14 appliance only at night as a retainer.

25.01

25.01

25.01

While we were observing for 4 months, this is what it looked like at the visit in May 2025.

25.05

As expected, after stopping the elastics, some relapse of the midline occurred, so it improved.

25.05

However, the front tooth alignment became distorted again, possibly because the last appliance that was supposed to be worn only at night was not worn regularly.

To correct this, we unfortunately had to proceed with a second remake.

25.05

25.05

The bite and lower arch alignment have been perfectly maintained.

From May 2025 to July 2025, we finished treatment after briefly wearing additional appliances to improve the front tooth alignment.

25.07

The midline is well aligned, and

the molar occlusion shows a tight Class I occlusal relationship.

Now let’s look at the before-and-after comparison.

The total treatment period was 1 year and 6 months, with a 4-month break in the middle due to the midline issue.

There were a total of 2 remakes.

24.02~25.07

Because the treatment result is on par with a proper adult orthodontic treatment result rather than a child orthodontic treatment result, the retention phase is also managed very thoroughly.

24.02~25.07

The deviated midline was corrected, and the tilted long axis of the front teeth also improved.

The deep overbite of the front teeth also improved.

25.07

The improvement in the long axis of the front teeth can be seen more accurately on X-ray.

24.02~25.07

24.02~25.07

Now let’s look at the facial comparison.

24.02~25.07

24.02~25.07

At our clinic, rather than being limited by the constraints of child orthodontic treatment, we do our best to provide treatment that achieves results comparable to adult orthodontic treatment.

We hope this post will be helpful for those considering clear aligners for children.