Extracting four teeth for braces is not always necessary, but it is sometimes the best option depending on how crowded your teeth are, how far forward they protrude, and how much space your jaw can realistically provide. Most orthodontists consider extraction once crowding reaches about 9 to 10 millimeters in either the upper or lower jaw. Below that threshold, non-extraction approaches can often work.
Why Four Teeth Instead of One or Two
When extractions are recommended, the plan almost always involves removing four teeth: one from each quadrant of the mouth. This keeps the bite symmetrical. Removing teeth from only one side or one jaw would throw off how the upper and lower teeth fit together.
The teeth most commonly removed are the first premolars, the ones sitting between your canines and molars. They’re chosen because of their position and size. Pulling them creates space right where it’s needed most: close enough to the front teeth to allow them to be pulled back into alignment, but far enough back that the gap closes invisibly during treatment. For cases with less severe crowding or specific bite issues, the second premolars may be removed instead, though this is less common.
The Main Reasons Extraction Gets Recommended
Crowding is the most straightforward reason. If your teeth overlap or twist because there simply isn’t enough bone to hold them all in a straight line, something has to give. Mild crowding (a few millimeters) can usually be managed without pulling teeth. But once the space shortage hits that 9 to 10 millimeter range, most clinicians shift toward extraction because the alternatives can’t reliably create that much room.
The second common reason is protrusion, where both the upper and lower front teeth angle outward. This is called bimaxillary protrusion, and it pushes the lips forward, creates a convex facial profile, and sometimes makes it difficult to comfortably close the lips at rest. For these patients, the goal isn’t just straight teeth. It’s pulling the front teeth back far enough to change the lip position and overall facial balance. Extraction of the four first premolars is the standard approach because it provides the space needed to move the front teeth significantly backward.
Certain bite problems, like a significant overjet (where the upper teeth sit far ahead of the lower teeth), can also tip the decision toward extraction when other methods would fall short.
What Happens to Your Face After Extractions
One of the biggest concerns people have is that removing teeth will make their face look “flat” or hollow. Research on 160 patients treated with four first premolar extractions found that the upper lip moved back an average of 3.4 mm and the lower lip about 3.6 mm. The angle between the nose and upper lip increased by roughly 5 degrees. For 80 to 90 percent of those patients, the profile was judged to have either improved or stayed satisfactory after treatment. Interestingly, 5 to 25 percent of patients (depending on the measurement used) actually ended up with lips that looked slightly more prominent after extraction treatment, not less.
The key point: when extractions are chosen for the right case, the facial changes are generally positive. Problems arise when teeth are extracted in a case that didn’t need it, or when the orthodontist retracts the front teeth more than necessary. That’s why the treatment plan matters more than the extraction itself.
The Airway Concern
You may have seen claims online that pulling premolars shrinks the airway and increases the risk of sleep apnea. The logic sounds intuitive: retracting front teeth could push the tongue backward into the throat. But the clinical evidence doesn’t support this fear. A systematic review and meta-analysis comparing extraction and non-extraction patients found no significant differences in minimum airway cross-sectional area or airway volume between the two groups. Multiple individual studies have reached the same conclusion. While it’s theoretically possible in extreme cases of over-retraction, standard premolar extraction does not meaningfully reduce your airway.
Alternatives That Can Avoid Extraction
Several techniques create space without removing teeth, but each has limits.
- Interproximal reduction (IPR): Your orthodontist shaves tiny amounts of enamel from the sides of teeth to create gaps. The safe limit is about 0.5 mm per contact point. Across an entire arch, this might yield 4 to 6 mm of space total, which helps with mild to moderate crowding but can’t substitute for the 7 to 8 mm a single premolar extraction provides.
- Palatal expansion: Widening the upper jaw can create space, but it works best in children and adolescents before the midpalate suture fuses, which can happen as early as age 12 to 13 and is typically complete by 20 in women and 25 in men. In adults, expanders mainly tip the teeth outward rather than truly widening the bone. Surgical expansion is an option but adds significant complexity.
- Molar distalization with TADs: Temporary anchorage devices (small screws placed in the jawbone) can push molars backward to free up space in the arch. Most studies show 3 to 4 mm of distalization is achievable in each arch, with a range of about 3 to 5 mm. This is a genuine alternative for moderate crowding but can’t match the space created by extracting two premolars from the same arch.
For mild crowding, combining IPR with some expansion or distalization can be enough. For severe crowding or significant protrusion, these methods simply can’t generate the space needed, and pushing their limits risks unstable results, root damage, or teeth ending up outside the bone.
Treatment Time With and Without Extractions
Extraction cases do take longer. A meta-analysis found that non-extraction treatment is shorter by an average of about 4 months. This makes sense: after teeth are pulled, the orthodontist has to close those gaps completely, which adds time to the process. If your case can genuinely be treated without extractions, you’ll likely finish sooner. But choosing non-extraction solely to save time, when your crowding or protrusion really calls for extractions, sets you up for a compromised result.
Long-Term Stability: Do Results Last?
A common worry is that extraction gaps might reopen or that removing teeth somehow makes relapse more likely. The evidence actually points in the opposite direction. A meta-analysis found no significant difference in relapse between extraction and non-extraction groups overall. When there was a difference, it tended to favor the extraction group. Several studies found that non-extraction patients experienced more crowding relapse over time, likely because the underlying space shortage was managed rather than resolved. One study measured irregularity relapse at 3.59 mm for non-extraction patients compared to 1.96 mm for extraction patients.
This doesn’t mean extraction is always more stable. Retainer wear matters enormously regardless of how you were treated. But you shouldn’t avoid extractions out of fear that the results won’t hold up.
How to Know If You Actually Need Them
The honest answer is that borderline cases exist, and two competent orthodontists might reasonably disagree on whether your case needs extractions. If your crowding is under 5 mm and your profile is balanced, extraction is rarely necessary. If your crowding exceeds 9 to 10 mm or you have significant protrusion with lip incompetence, extraction is hard to avoid without compromising the result. The gray zone sits between those extremes, and that’s where getting a second opinion is most valuable.
When evaluating a treatment plan, ask your orthodontist specifically how much crowding you have in millimeters, whether your concern is crowding alone or also protrusion, and what tradeoffs the non-extraction approach would involve in your case. A good orthodontist won’t recommend pulling healthy teeth unless the alternative is a worse outcome for your teeth, your bite, or your face.