Non-Extraction Orthodontics for Crowded Canines with Invisalign, Edge-to-Edge Bite, and Crossbite: 1 Year 6 Months of Treatment

Hello.

This is Apgujeong Orthodontic Clinic.

Today, I’ll show you how severe crowded canines can be treated without extraction, and also with Invisalign.

23.09~25.03

When teeth are completely overlapping and there is not even 1 mm of space for the crowded canine to line up, the first-choice treatment is of course extraction orthodontics. However, if only the canine side is extracted, that is usually not enough, and the other premolars often also need to be extracted, so in many cases four teeth must be removed.

But if the patient wants non-extraction treatment, and we judge that it can still be treated without extraction, we may proceed that way.

Today, I’ll show you such a case.

This patient visited in August 2023 for orthodontic treatment.

There was only one thing they wanted to fix: the crowded canine.

23.09

One left canine is completely out of alignment.

When there is a crowded canine, the midline tends to shift toward that side.

You can see that the upper front tooth midline is tilted toward the crowded canine side.

23.09

There is not even 1 mm of space for the canine to move into place.

This is severe crowding.

The front teeth show a crossbite, where the upper teeth do not overlap the lower teeth, and an edge-to-edge bite.

In this case, when closing the mouth, the lower lip can look prominent and the mouth appearance becomes unnatural.

The patient wanted Invisalign treatment and also wanted a non-extraction approach, so we made the treatment plan accordingly.

For the lower jaw, we pushed the molars backward using the space from the wisdom teeth so that the lower front teeth would move back by 2 mm in the end.

Likewise for the upper jaw, we planned to move all the molars backward into the wisdom tooth space to create room for the crowded canine to align.

As the crowded canine comes into place, it is important to pay close attention so that the surrounding teeth do not flare out more than before, even if the treatment plan becomes a bit complicated.

The first set contained 66 aligners.

From September 2023 to May 2024, this is what it looked like after wearing the aligners for 8 months.

Treatment start

24.05

Not much change in the front teeth after 8 months, right?

Most of the first 8 months were spent moving the molars back one by one. At least one orthodontic mini screw is needed in each quadrant.

24.05

Fortunately, the patient wore the aligners diligently.

In November 2024, this is what it looked like after all 66 aligners had been worn.

24.11

The crowded canine found its place, and there is still midline discrepancy.

24.11

Now that the crowded canine has been resolved, the major work is done.

24.11

To improve the areas where the molar bite was open and the spots that were contacting too early, we moved on to a refinement phase.

The number of additional aligners for refinement was 17.

To stabilize the molar bite and improve the midline, elastics were prescribed in the refinement phase.

25.03

This is what it looked like after wearing all the aligners from January 2025 to March 2025.

The total treatment period was 1 year and 6 months.

25.03

Finally, the tooth midlines match perfectly, and the crowded canine is stably aligned.

It is important not only for the upper and lower tooth midlines to match, but also for the overall relationship with the philtrum and face.

25.03

If the molar bite is not good, we do not finish treatment.

25.03

Now let’s compare before and after treatment.

23.09~25.03

The initial 3 mm midline discrepancy has been resolved.

The amount of overlap of the upper teeth over the lower teeth is stable.

The crowded canine came down nicely.

23.09~25.03

The front teeth that were previously in crossbite also found a normal bite.

Now let’s compare the facial appearance before and after.

A tooth midline that matches the face and a neat smile line

23.09~25.03

The smile has become much prettier and more natural.

During treatment, the patient had a personal matter worth celebrating, so we were unable to take an X-ray after finishing treatment.

The lower front teeth moved backward by 2 mm using the wisdom tooth space.

As the front tooth crossbite and edge-to-edge bite were resolved, the lower lip also moved back by 2 mm.

The upper front teeth were treated so they would not move forward as planned, so there is no change in the upper lip.

24.11

This is the panoramic X-ray taken when refinement began.

There is no root resorption, and the root parallelism is good.

Because we improved the anterior tooth axes further during refinement, the root parallelism would likely have improved even more on the X-ray taken after treatment was fully completed.

I hope this post helps those who are afraid of extraction and are considering crowded canine correction because of extraction.

Thank you.