Orthodontic Extrusion for Implant Site Development Revisited: A New Classification Determined by Anatomy and Clinical Outcomes
Abstract
A contemporary approach to achieving optimal implant esthetic-restorative outcomes requires the knowledge to properly diagnose, coordinate, and execute complex interdisciplinary care. Implant site development utilizing orthodontic extrusion requires an understanding of many important concepts and principles of both disciplines of orthodontics and periodontics. This article reviews basic concepts of orthodontic extrusion and emphasizes a new diagnostic periodontal classification scheme of the pre-treatment anatomy that anticipates osseous and soft tissue responses to orthodontic extrusion. Type 1 classification, the attached gingiva is connected to both bone and root surface, and during orthodontic extrusion an increase in the width of attached gingiva will occur. Type 2 classification, the attached gingiva and MGJ is connected to the root surface, and during orthodontic extrusion the gingival tissue moves coronally with the tooth, but an increase in the width of attached gingiva does not occur. Type 3 classification; a periodontal pocket is present and during orthodontic extrusion the free gingival margin does not move coronally until there is a complete elimination of the periodontal pocket. In addition, the article provides a greater understanding of the orthodontic biomechanical principles and techniques that should be selected based on anatomical considerations for each patient. Mastering the diagnostic and technical aspects of orthodontic extrusion is an invaluable addition to the interdisciplinary practice as it can provide an effective means to treat soft tissue and osseous vertical deficiencies of the periodontium. Orthodontic extrusion may therefore represent a unique treatment alternative to some of the most challenging esthetic situations.