By Dr. Mahmoud Abu Zainah
An examination of the significance of alveolar ridge and socket preservation in implant therapy
Maintaining optimal alveolar ridge dimension and socket preservation following tooth extraction are key goals in implant therapy. Once the tooth is extracted, hard and soft tissue remodeling is part of the normal physiologic healing process that occurs to the remaining edentulous ridge. This remodeling negatively affects the ridge dimensions in the buccolingual and apicocoronal aspects. For premolar and molar sites, Schropp et al report ridge width reductions up to 50% (an average loss of 6.1 mm) within the first year post-extraction. With respect to anterior and premolar sites, a systematic review described an average loss of 3.87 mm in ridge width, and 1.67 to 2.03 mm in ridge height. Considering these ridge alterations may hinder optimal implant placement, compromise esthetics, and create unfavorable defects around neighboring teeth and prostheses, minimizing this bone-resorptive process has been extensively researched. For clinicians, the goal is to provide treatment that preserves the natural tissue contours of the ridge following tooth extraction.
Alveolar socket preservation has been used to describe “a technique in which completely contained extraction sockets are filled with a bone substitute material and/or sealed with membranes, whereas in alveolar ridge preservation, damaged extraction sockets are also included.” Conversely, some review articles consider the terms interchangeable and mainly use alveolar ridge preservation, which has been described as “any procedure developed to eliminate or limit the negative effect of postextraction resorption, maintain the soft and hard tissue
Ridge preservation techniques can be divided into the surgical aspect and material selection aspect.
Surgical Considerations: These mainly relate to the extent of soft tissue manipulation surrounding the extracted tooth. A flapless approach generally means no soft tissue manipulation flapped approach usually involves vertical-releasing incisions, flap reflection and coronal advancement to achieve primary closure.
Material Selection: Alveolar ridge preservation procedures have been extensively tested with numerous materials and combination of materials, such as:
- Bone grafting alone (including autografts, allografts, xenografts and alloplasts)
- Membrane alone (including resorbable or nonresorbable)
- Combinations of membrane and bone grafting