Amongst the consequences of missing teeth are change of appearance and difficulties in mastication and speech. Dental implants in the maxilla or mandible provide a common treatment modality by offering anchorage to fixed or removable fixtures. In many cases, the lack of teeth is accompanied by lack of appropriate bone volume in the desired area for dental implant placement. Possible causes for this lack of sufficient bone volume are varied and include earlier bone atrophy, traumatic tooth extraction and bone resorption due to periodontal disease. In such cases, dental implant placement is preceded by alveolar bone augmentation . Guided Bone Regeneration (GBR) is a common bone augmentation technique in which a bulk of bone substitute is placed in the area which needs more volume before placing a dental implant. The bone substitute is covered with an inert membrane and may provide a scaffold and encourage cells from the patient to reach the area and build new bone volume. A common bone substitute in use for that matter is Deproteinized bovine bone mineral (DBBM) which resembles human bone and helps encourage new bone formation. On the contrary its structural stability during placement and early healing is low. Bi-Phasic Calcium-Sulphate is another common bone substitute with easy handling properties and good structural stability during early healing. Its replacement by natural bone contributes to the augmentation process. Although DBBM efficacy in GBR process has been investigated, using DBBM in combination with bi-phasic calcium-sulphate as a binding material during GBR was not examined. This prospective study will examine augmented bone quality and quantity following a GBR procedure with common approved bone substitutes: DBBM (Bio-Oss, Geistlich) alone or in a combination with bi-phasic Calcium-sulphate (BondBone, Augma). The GBR procedures will precede dental implant placement as custom. The quality and quantity of the new formed bone will be assessed by a C.T (computerized tomography) which is done routinely before dental implant placement and by further analyses of bone residues which will follow drilling the dental implant placement site while preparing it (as common).

Inclusion Criteria:

• Healthy men and women over 18 years of age, eligible for signing
• Edentulus Patients who require a GBR procedure previous to an insertion of a dental implant
• Patients who understand the meaning of the treatment (routine Guided Bone Regeneration and dental implant insertion) and the follow up study, and approves participation in booth of them

Exclusion Criteria:

• Pregnant or nursing women.
• C567890-hildren or non judgemental patients
• Patients with uncontrolled diabetas mellitus, rheumatoid arthritis or osteoporosis.
• Patients with a pathology present near the site of dental implantation