Ask us - Send your scientific questions to ''Ask Us,'' AJO-DO, University of Washington, Department of Orthodontics, D-569, HSC Box 357446, Seattle, WA 98195-7446 or, via the Internet, to dlturpin@@aol.com. Include your name, mailing address, and e-mail address. We will send selected questions to a few of our expert reviewers for the answers. Questions and answers will be published together in future issues of the Journal.