What Is an Underbite and Do I Need Surgery?
An underbite can affect both function and appearance. Here is a guide to understanding your treatment options.
An underbite occurs when the lower teeth sit in front of the upper teeth when the mouth is closed. This happens when the lower jaw is too far forward, the upper jaw is too far back, or both.
- Treatment options depend on severity:
- Mild underbite β may be correctable with braces, elastics, or Invisalign
- Moderate to severe underbite β nearly always requires surgery because the underlying jawbone is the problem
- How surgery fixes an underbite:
- If the upper jaw is too far back: maxillary osteotomy moves the upper jaw forward
- If the lower jaw is too far forward: mandibular osteotomy moves the lower jaw backward
- Often both jaws need surgery (bimaxillary) for the best result
Signs Your Underbite Needs Surgery
- Your lower teeth are noticeably in front of your upper teeth
- You have difficulty biting and chewing
- You have speech problems (lisp or whistling sounds)
- Your lower face appears prominent or "bulldog-like"
- You have jaw pain or clicking
- You avoid smiling or feel self-conscious about your profile
When to See a Surgeon
See an oral surgeon if your underbite is more than a few millimeters or if it causes functional problems. Surgery is typically recommended after jaw growth is complete (age 16+ for females, 18+ for males).
Clinical Guidance
A moderate to severe underbite usually requires orthognathic surgery to reposition the lower jaw, upper jaw, or both. Braces alone cannot correct a skeletal underbite because the problem is in the bone, not the teeth.