a Dr. Nasser D. Alqahtani 15 Assistant Professor, Division of Orthodontics 16 Department of Pediatric Dentistry and Orthodontics 17 College of Dentistry, King Saud University 18 P.O. Box 60160, Riyadh, Zip Code 11545, Saudi Arabia 19 Telephone: +966553446684. Fax: +966-14679017 20 E-mail: [email protected] 21 22 b Dr. Thikriat Al-Jewair 23 Assistant Professor, Department of Preventive Dental Sc...
