Why age seven
Around seven, enough permanent teeth have erupted and enough jaw growth has happened for an orthodontist to see how things are developing — while there is still growth left to work with.
Most children who are seen at seven need nothing yet. The value of the visit is knowing that, knowing what to watch for, and knowing someone is monitoring your child's dental development with you.
What early treatment involves, when it's needed
When early treatment is warranted, it is usually limited and targeted: guiding growth or creating room, rather than straightening every tooth.
Dr. Khan will explain what phase one is meant to accomplish, what it does not accomplish, and that a second phase is typically expected later — so nobody is surprised by that conversation years from now.
What if we just wait
A fair question — and one of the ones answered honestly on Ask Dr. Khan. She will go through the pros and cons of waiting in your specific case.