What is the fine-grained topic of the following text: Selecting an orthodontist who is a member of the American Association of Orthodontists (AAO) is your assurance that you have chosen an orthodontist: the dental specialist with at least two to three years of post-doctoral, advanced specialty education in orthodontics in a university-based program accredited by the American Dental Association. Only return the topic.
Choosing an AAO-accredited orthodontist