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Abstract
The alveolar bone is different from any other bone in the body due to its extremely high turnover and metabolic rate. The main functions of the alveolar bone are to support teeth and to respond to high impact stress exerted on it. (1,2)
Tooth loss is responsible for alveolar bone atrophy leading to decrease in both bone height and width. The resultant ridges present functional and esthetic problems to prosthodontists as well as implantologists. Unesthetic dental restoration and over closure are among the problems that are accelerated by loss of alveolar bone.(3) These problems could be prevented by following a simple procedure termed ridge preservation. It is performed by placing one of the variety of bone grafts and/or grafting materials into the alveoli immediately after extraction.(4)
With the exception of blood, bone is the most frequently transplanted tissue in humans. Autogenous bone is considered the gold standard in bone grafting. It is resorbable, eventually replaced by the patients own bone, and is non-allergic. However, autogenous bone has a number of major drawbacks.The available supply of transplantable tissue is often insufficient for large defects, particulary in children, and there is significant risk of post-operative morbidity at the donor site (pain, hemorrhage, wound problems, cosmotic disability, infection, nerve damage).(5)
Moreover; many types of bone graft materials have been used for ridge preservation after tooth loss. The concept for selection of materials depends on placement of biologically compatible material in the debrided alveolar socket to prevent collapse of bone.(6)
Bioactive glass is a non-resorbable material whose medical use evolved 30 years ago. Bioactive glass is now clinically approved for use in dense form in non-load bearing application such as endossous ridge implants and as a particulate for periodontal defect repair. The use of bioactive glass granules in extraction socket prior to delayed implant placement was statistically significantly increases the interfacial and distant amount of bone tissue compared to implants placed in untreated control areas. These beneficial effects were the direct result of the osteoconductive and osteostimulative properties of these bioactive glass granules of narrow size range. (4,6)
In addition; demineralized freeze dried bone allograft (DFDBA) have been successfully used to reconstruct intra-osseous periodontal defects and furcation defects. The current wide spread use of DFDBA is based on the osteoinductive ability of bone graft preparation where demineralization of the graft exposes the bone inductive proteins (bone morphogenetic proteins) located in the bone matrix. (5,6)