Orthodontist

An orthodontist is a dentist (a doctor that works on teeth) that specializes in straightening teeth with things like braces.
Training.
An orthodontist needs to go to dentistry school first. Then they need 3-4 years more of school to become an orthodontist.
Practice.
An orthodontist straightens teeth using braces (metal wire attached to teeth), headgear (metal wire that may attach to teeth and the neck or head), and retainers (removable wire and plastic). They may also pull teeth, or perform surgery.