eli5: If osteoclasts and osteoblasts restructure bone density while wearing braces, why do teeth shift back to their original positions if a retainer isn’t regularly worn? Why isn’t the change in bone density permanent?

Question

​

In: Biology

Answer 1

Each tooth has a ligament at the base called the periodontal ligament. When we wear braces, we shift the bone structure to adjust to the new position of the tooth, but if the teeth are crooked due to genetics (as opposed to pressure from other teeth for example), that ligament will pull on the tooth once you remove the braces and can bring them back to their original position

Aside from that, teeth grinding, bad pronunciation habits or bad resting tongue placement in the mouth can exacerbate that effect