**1. Introduction**

Alveolar bone loss as a result of teeth extractions, periodontal disease, dentoalveolar trauma, pathologic conditions, failed implants, and failed bone grafting procedures may provide poor bone quality in height, width, and angulation which may result in impaired intermaxillary relationships. Ridge augmentation is considered in such cases to enhance the insertion of dental implants with good diameter and length at a proper prosthetic

position. Several augmentation methods and materials have been successfully used during the last decades, but much controversy still exists [1–10].

Autogenous bone grafts are still considered as the gold standard not only because of their osteogenic, osteoinductive, and osteoconductive biological activities but also due to their safety and their excellent incorporation in the recipient bed. Common extra donor sites such as iliac crest, rib, tibia, and cranium are used and provide large quantities of cortical and cancellous bone. However, extraoral donor sites have several disadvantages that include the need for hospitalization and general anesthesia, prolonged healing time of donor site, concomitant morbidities, and visible scars [11–17].

Different intraoral donor sites are widely used as bone blocks or particulate bone. The most common intraoral sites are the symphysis and ramus/retromolar area [18–22], they have different degrees of morbidities and complications [23–27]. Nonautogenous bone grafts such as allografts, xenografts, and synthetic bone substitutes are widely used either alone or in combinations [28–34]. They eliminate the potential complications associated with autogenous donor sites and their availability is unlimited, however, they have osteoconductive characteristics and lack of osteoprogenitor cells.

The incorporation of the autogenous bone graft at the recipient site depends mainly on the amount of revascularization together with remodeling and substitution of the graft, which leads to the integration of the graft at the recipient bed [35]. There is a solid connection between osteogenesis and revascularization inside and around the graft [36]. Revascularization of the bone graft starts when blood vessels sprouts grow and go through the bone block. They originate from two sources; first, from the bone at the recipient bed, and second from the surrounding soft tissue. Hammack and Enneking in 1960 found that penetration of the blood vessels to the cortical graft was observed on the sixth day [37]. De Marco et al. in 2005 reported the timing and the penetration rate of the blood vessels into the autogenous bone block in rats. New capillaries had migrated from the surface of the recipient bed and penetrated the graft to different degrees [38].

Graft fixation plays a crucial role in cortico-cancellous bone grafts survival. Fixation screws are usually used to prevent micromovement of the augmented bone blocks at the recipient site, preventing and minimizing early graft volume loss and infections [4, 39, 40]. This chapter introduces a new bone augmentation method, Wedge Technique (WT) as a biological approach that utilizes the main advantage of autogenic bone which is transferring living cells, and the main advantage of the allogenic bone as well which is the availability and the unlimited quantities. The surgical procedures of WT, including bone block harvesting, wedge preparation, recipient site preparation, and the augmentation methods are presented in this chapter. The biological rationale, the healing process, and the advantages of the WT are explained and discussed.

## **2. Patients and methods**

Patients were referred by their surgeons due to different types and degrees of alveolar bone deficiencies, a lot of them result from failed implants or failed previous bone augmentation attempts. The majority of the cases had at least two sites at one or both jaws, and the majority of the sites were at the posterior mandible (**Table 1**). Inclusion criteria for the use of wedge-technique in the participants were: atrophic alveolar ridge

