Why does the mouth go back after orthodontics with extraction?
Because when the front teeth are moved back into the space left by extracting premolars, the lips that the front teeth supported also follow inward. I often hear the question, “If I have four healthy teeth pulled, won't my cheeks look sunken?” Extraction itself does not bring the mouth back or make the cheeks sunken. Where that space is used is what changes the mouth.
| Where the extraction space is used | Change in the mouth |
|---|---|
| Moving the front teeth back a lot | Likely to look set back |
| Straightening overlapping teeth | Small change |
| Hardly moving the front teeth back | Still looks protruding |
Do the lips go back as much as the teeth?
No. The lips follow only part of the amount the teeth move. Generally, the upper lip tends to follow by around half the front teeth's movement or less, and the lower lip by a little more, but the range varies widely from person to person. Lip thickness and tension and the position of the nose and chin together determine the change.
For people with thin lips, the same movement feels larger. Conversely, for people with thick, tense lips, the change in the lips can look small even when the front teeth go back. So I don't promise that it will go back by a certain number of millimeters, and I don't say it will make you look younger. Instead, we decide together, looking at photos, how much change would look natural for your current profile.
Will my mouth look sunken after orthodontics with extraction?
The extraction itself is not the cause. The mouth looks sunken when the front teeth are moved back excessively, beyond the range the bone and lips can support. The same happens when teeth are extracted to bring back a mouth that wasn't very protruding to begin with.
So while closing the space, I check the profile along the way and adjust how much further to move the front teeth back. Bringing front teeth forward again after they have been moved back too far is harder than the original plan.
Conversely, if teeth are extracted but the front teeth aren't moved back enough, the mouth still looks almost as protruding as before. That result happens when the extraction space is closed only from the back-teeth side and the angle of the front teeth is changed less. The bone and lips decide how far the teeth go back. I also don't blame orthodontics for cheeks that look different because of aging or weight changes.
How is it decided whether to extract?
It isn't decided by a single number; I look at the following together.
- The shortage of space, the current position of the front teeth, and the amount of movement needed
- The range of alveolar bone the teeth can move within
- Lip protrusion and the relationship of nose, lips, and chin
- How the upper and lower teeth will ultimately bite together
If one plan involves extraction and another doesn't, rather than asking which one is right, it is better to compare side by side how the front tooth position and lip line change under each plan. The difference between the two approaches is covered in The difference between orthodontics with and without extraction, and why teeth are extracted is covered in Why teeth are extracted for orthodontics.
How we do it at Wonjin Dental
At the consultation, I explain side by side where the front teeth will sit and how the lips will look with and without extraction. A protruding mouth doesn't automatically mean extraction, and I don't force the front teeth back in a direction the bone can't support. That is because gums do not grow back. Orthodontic diagnosis is ₩100,000, and the cost of each appliance is listed in All fees.
Frequently asked questions
How many teeth are usually extracted for orthodontics?
Extracting four premolars, upper and lower on both sides, is common, but sometimes only two are extracted or other teeth are extracted. The number and position depend on your teeth, bite, and goals.
When does the extraction space close?
It closes gradually as the teeth are moved during treatment. Full orthodontics usually takes 1 year 6 months to 2 years 6 months, and the space does not remain at the end of treatment.
Does my profile keep changing after orthodontics with extraction?
Once the space is closed and the front teeth have settled, changes in the mouth mostly stop too. However, the lips thinning and sagging with age continues regardless of orthodontics.
I'm worried about the gap showing early in treatment.
Early in treatment, the extraction site may be visible. If the site is near the front, there is also the option of attaching a temporary tooth shape to the appliance to hide it.
