... digital era . Journal of Clinical Orthodontics 36 : 221 – 236 Ackerman J L , Ackerman M B , Brensinger C M , Landis J R 1998 A morphometric analysis of the posed smile . Clinical Orthodontics ... parted) and a full dentition record with the aid of cheek retractors were made. The reliability and clinical application of this digital videographic measurement method has been tested previously. ... consider when evaluating the aesthetic zone, is the effect of age on lip line height. Based on clinical experience, the prosthetic literature demonstrates that with age the lips become less...