Dental braces

You can ask a question right away. My child's teeth have grown in time, with all the baby teeth almost replaced by permanent teeth. But one incisor came out the second row and won't stay in place. We thought about putting in a mouth guard to align the teeth, but we were denied. We decided to get braces. The child at age 6 cannot wear braces because the jaw is still growing and expanding. I am worried. We plan to go to sloancreekdental.com as they have knowledgeable dentists. I would like to know in advance the specifics of a child's jaw structure and how to talk to the dentist if he insists on permanent braces.