The aim of this study was to investigate the quality of newly formed tissues after using Bio-Oss as a graft material and also to determine the level of BONE REGENERATION and BONE thickness. The incidence of inflammation and any type of forgein body reaction, following using this material was also studied. Five male sheep of the same age, race, weight and systemic condition were selected and 10 surgical defects (5x5x5mm) were created in their mandibular site. At random, one side was filled with Bio-Oss as the test group and another side as the control group, was not filled with any type of graft material. After 6 monthes, the animals were sacrificed and studied histologically and histomorphometrically. The data were analyzed by Mann-Whitney U test showing that the mean percentage of the regenerated BONE and the density of the newly formed BONE in the test group were statistically more than the controls (p=O.OO4).No inflammation and forgein body reaction were observed in Bio-Oss group.It is concluded that applying Bio-Oss graft material in BONE defects can bear useful results. This material can also be successfully used in the procedures of sinuslift and ridge augmentation for implant placement.

Guided BONE REGENERATION (GBR) is a reconstructive procedure of alveolar ridge using membranes. This procedure is indicated when there is no sufficient BONE for implantation, or in the case of optimal implant installation for esthetic or functional needs. GBR can be performed before implant placement, when there is not enough BONE for initial stability of implants and less predictable outcomes (staged approach), or performed simultaneously with implantation (combined approach). GBR techniques have been used for vertical and horizontal ridge augmentations with acceptable results. This literature review discusses the background, principles of GBR, the materials used in GBR (types of membranes and BONE grafts), success criteria and long term results of GBR.