General guidelines for use of BONE GRAFTING
1. The surgical site should be prepared, that is it should be free of granulation tissue.
2. For autogenous grafts- the donor site should be exposed and the graft collected and the bone crushed or if block graft shaped to match the site and stored in saline.
3. When using alloplastic/xenograft etc. the graft should be reconstituted with patient's blood or with physiological saline prior to implantation. Mixtures of alloplastic/xenograft with allograft/autografts are recommended while grafting larger sites to seed regenerative potential in the scaffold grafts.
4. The graft should be placed at the recipient site. The graft recipient site should normally have vital bone tissue devoid of any acute or chronic infection. Sometimes, the site may have to be freshened ie. have small holes drilled to promote bleeding e.g. In autogenous block grafts. The graft may be modelled to suitably ensure the objective of grafting the defect/augmentation. The graft needs to be stabilized in case of block grafts by bone screws. Particulate grafts stabilize due to the clotting of blood and are supported by the overlying membrane.
5. A barrier membrane may be used to stabilize and exclude the graft from epithelial and fibrous tissue and the various types of membranes available have been discussed in the theory text. The membranes have specific surfaces which are to be placed on bone or tissue side and the manufacturer's instructions should be followed. Most membranes are available with template which can first be used to select the shape and model the membrane as per the requirements of the particular clinical situation. It is important though to cover the bone defects and overlap the walls by at least 2mm to allow complete bone contact and prevent lateral gingival connective tissue intrusion.
6. Stabilization of membranes - generally resorbable membranes are hydrophilic and swell up when in contact with blood and are coherent i.e., lending themselves to stable placement, However, fixation of membranes may be required by tacks or suturing through the membrane. It is always better to tack the membranes even if they appear to be stable without the use of tacks.
7. The mucoperiosteal flap should be sutured over the membrane (with no membrane exposure) without tension using either single interrupted sutures or mattress sutures