What is the teeth whitening method orthodontist patients use?

Bleaching. Cleaning can whiten, but bleaching can whiten beyond the natural color. It is not, however, innocuous; it can irritate the gums, make teeth hypersensitive and hurt the enamel of one's teeth..
Aligner bright. Many orthodontists use a low concentration carbamide peroxide bleaching agent called aligner bright. It is specially made for ortho patients.
DONT!! If you are currently and orthodontic patient don't whiten! this will cause you to have discolored patches on your teeth when the braces come off. Wait for the braces to come off then whiten. If you are planning on getting braces do it before and then wait until they are done. Talk to your provider for more details.
Depends. There are many bleaching systems available. Most have a combination of in-office and at-home use for the best results.