Alveolar bone preservation following tooth extraction: a perspective of clinical trials utilizing osseous grafting and guided bone regeneration

摘要

Edentulism is still a highly prevalent condition in the American population. Over 20 million teeth are extracted in the United States every year, with 40% of the American population over the age of 60 being edentulous [1]. Alveolar bone resorption is a common consequence of tooth extraction [2,3] and it poses a clinical problem in two different ways: it creates an esthetic problem for the fabrication of conventional or implant-supported prostheses and it can make the placement of dentaTimplants difficult or sometimes impossible. Therefore, preservation of alveolar bone dimensions following tooth extraction is desirable.A review of the literature (up to the mid-1990s) on the effect of various materials and surgical techniques in preserving alveolar ridge dimensions following tooth extractions was limited to various case reports or studies that did not employ a fixed reference measurement point [4-10]. Although the concept of alveolar ridge preservation following tooth extraction made biologic sense and case reports illustrated well the clinical applications of that concept, controlled clinical trials demonstrated no actual evidence that alveolar ridge preservation procedures were effective. The need to objectively examine the effectiveness of alveolar ridge preservation procedures was recognized by the authors' group at University of California-Los Angeles, and they conducted three clinical trials [11-13] that focused on the role exerted by various regenerative materials and techniques in preserving alveolar ridge dimensions following tooth extraction.