1. Esthetics: The orthodontic-periodontic restorative connection;Kokich;Semin Orthod,1996
2. Perspective of facial esthetics in dental treatment planning;Mack;J Prosthet Dent,1996
3. Esthetic considerations in orthodontic treatment of adults;Margolis;Dent Clin North Am,1997
4. The principles of visual perception and their clinical application to denture esthetics;Lombardi;J Prosthet Dent,1973
5. The gingival smile line;Peck;Angle Orthod,1992