HEALING OF OSSEOUS DEFECTS USING DEMINERJQIZED-FREEZE DRIED BONE WITH RESORBABLE AND NON-RESORBABLE MEMBRANES (AN EXPERIMENTAL STUDY)

Abstract

The restoration of osseous defects represents a problem inherent to many dental and medical specialists including oral and maxillofacial surgery. Defects created by congenital anomalies, neoplasms, trauma and orthognathic surgical procedures are regularly faced by the surgeon (I).

The introduction of bone-grafting techniques in the late nineteenth century, led to their use in the treatment of nonunions, filling of bone cavities secondary to infection, replacement of bone loss secondary to trauma or tumour reconstruction, and replacement of joint surfaces (2).

In view of its osteoinductive capacity and lack of immunogenicity, autogenous bone is considered to be the most suitable bone graft. The greatest disadvantage in the use of autogenous tissue is the necessity of a second surgical procedure with the associated risks of prolonged anesthesia, increased blood loss, donor site morbidity and patient discomfort(!).

Decalcified freeze-dried bone allograft (DFDBA) has been widely used m dentistry and medicine since 1965. Urist demonstrated that DFDBA can stimulate the formation of new bone through osteoinduction. Demineralization of the bone allograft with hydrochloric acid exposed a family of bone morphogenic proteins, now characterized in the Transforming Growth Factor( TGF-B )superfamily, which may induce undifferentiated host mesenchymal cells to differentiate into osteoblasts followed by bone formation (3).

Guided tissue regeneration Is a surgical technique that uses a physical membrane barrier to prevent the ingrowth of undesirable cell populations at the surgical site