How do I get approved for orthodontists exam for braces?

Call . Call the orthodontic office. Somme insurance companies let you call without a referral, some require your primary dentist to introduce you. No insurance, just call and schedule an exam.
Orthodontia. There is no qualification process for braces. You either need braces or you don't. There is one insurance company that i know that has guidelines to decide whether or not they will pay for braces. You can't do anything to get qualified for them to pay. You either meet their criteria or you don't. Good luck.
Submit predeterminat. First read your benefits book/talk to your hr person and see if braces are covered and for what - then get a referral within coverage parameter and then submit predetermination paperwork.
No approval required. Most orthodontists offer free complementary consultation. Call a local office for your consultation. You can also ask your dentist to suggest an orthodontist he likes to work with for better coordination of your dental and orthodontic treatments.