When is non-extraction orthodontics possible?
When the space needed is not large, the front teeth and lips are not already protruding, and that space can be opened by other methods. I often hear the question “Do I have to pull healthy teeth too?”, but I do not decide just by how many teeth look crooked from the outside. Two sets of teeth that look similar can mean non-extraction for one person and extraction for another.
- The space shortage is small.
- Protrusion of the front teeth and lips is not large.
- The gums and alveolar bone (the bone supporting the teeth) can withstand expansion and movement.
- There is room behind the molars to move them.
How is space made without pulling teeth?
There are three methods, and two or more are sometimes used together.
| Method | Where the space is opened | Limit |
|---|---|---|
| Interproximal reduction | Thinly trimming the enamel on the sides of the teeth | Not enough if the shortage is large |
| Arch expansion | Widening the dental arch | Pushing teeth outside the bone makes the gums recede |
| Moving the molars back | Anchoring with mini-screws (TADs) and moving the row of teeth back | How far back the bone allows |
When the space shortage is small, interproximal reduction and mild expansion are often done together with clear aligners, and when the molars need to move back a lot, using screws together with fixed braces is more predictable. Whatever the appliance, the amount of space needed comes first, and the appliance comes after.
Interproximal reduction only trims very thinly within the enamel, so it cannot make up for a large shortage. The details are in Why the spaces between teeth are trimmed during orthodontics. To move the molars back, the wisdom teeth sometimes need to be removed.
When should non-extraction orthodontics not be done?
If the teeth are straightened without space, the front teeth come forward. The front teeth support the lips from the inside, so if they tip forward, the mouth looks more protruding. In a mouth where the front teeth or lips already protrude, this path is even riskier. Conversely, pulling a mouth with almost no protrusion too far back also looks unnatural.
Non-extraction usually means not pulling premolars to make space for alignment. It is not the same as not pulling any teeth at all. Gums do not grow back, so we also do not make plans where excessive expansion makes the gums recede.
How can I know if non-extraction is right for me?
You find out through a detailed diagnosis. It is hard to decide between extraction and non-extraction from photos of the teeth alone. I look at the items below together.
- The actual amount of space shortage and the position and angle of the front teeth
- How the upper and lower teeth bite together
- The lips and side profile
- The gums and alveolar bone, and the position of wisdom teeth and roots (X-rays)
In consultation, I recommend going one step further than “Can it be done without extraction?”: how much space is missing, how it will be made, and where the front teeth and mouth will sit as a result. Once these three are explained, the direction becomes clear. The difference between the two approaches is summarized separately in The difference between extraction and non-extraction orthodontics.
How we do it at Wonjin Dental
In the orthodontic diagnosis, we look at the items above and first map out where the front teeth and mouth would sit without extraction. If the front teeth come forward in that plan, we do not go non-extraction. This is not because non-extraction is a better choice than extraction, but because it has to be the path that fits your current teeth, face, and goals. An orthodontic diagnosis is ₩100,000, mini-screws are ₩100,000 each, and the full costs are on All treatment fees.
Frequently asked questions
Is non-extraction orthodontics shorter?
It is sometimes shorter because there is no step of closing extraction spaces. However, if the molars need to move back a lot or the expansion is large, it can take about as long as extraction orthodontics or longer.
Can adults have arch expansion too?
Unlike during growth, it is hard to widen the bone itself, so the arch is widened only to a limited extent by adjusting the tilt of the teeth. That is why it is hard for adults to gain a lot of space through expansion alone.
Is relapse more likely after non-extraction orthodontics?
Widened arches tend to return to their original shape. The more the arch is expanded, the more important it is to wear retainers consistently.
Does interproximal reduction weaken the teeth?
If only a very thin layer is trimmed within the thickness of the enamel, the risk of cavities or sensitivity does not increase much. The trimmed surfaces are finished smooth, and you just need to clean between them well with floss.
