Why Does the Jawbone Shrink After a Tooth Is Extracted?

Bone remains as long as it's used

The force transferred from a tooth's root to the bone during chewing sends a constant signal to bone cells. When a tooth is extracted, that signal stops and the body starts resorbing the now-unused tissue — this is called resorption.

How fast is the loss?

Loss is fastest in the first year: the extraction site's width shrinks by roughly 25% on average.

Knock-on effects

• Neighbouring teeth tilt.
• The opposing tooth over-erupts.
• Lower face height decreases.
• Load increases on the jaw joint.

Ways to prevent resorption

Socket preservation: placing graft material in the socket at extraction preserves most of the bone volume. Early implant: an implant transfers chewing force back to the bone, stopping resorption.

What if it's too late?

Lost bone can be regained with graft and membrane techniques; this extends treatment by a few months.