The introduction of skeletal anchorage has changed the profession of orthodontics. Tooth movement that was once only possible through orthognathic surgery can now be accomplished with miniscrews and plates. However, data on the impact of these dentoalveolar movements on the periodontium and teeth, as well as their stability are rather limited. This lecture will review and update the concept of the “Envelope of Discrepancy” introduced by William R Proffit to describe the range of dentoalveolar movement. It will discuss and highlight ongoing 3D imaging research to show potential side-effects of large dentoalveolar movements including popular skeletal anchorage treatment protocols correct AP discrepancies, vertical, and transverse deficiencies.
Learning Objectives:
After this lecture, attendees will be able to:
Review 3-D data on the range of possible tooth movement.
Outline potential periodontal side-effects and root resorption in cases involving large incisor retraction for Class II and Class III correction.
Discuss stability and periodontal impact of skeletal anchorage bone-borne expansion.
