ABSTRACT
There are several bone-grafting materials that can be used in bone regeneration procedures. These materials include autogenous bone, allogeneic substitutes as demineralized freeze-dried human bone, xenogenic substitutes as deproteinized bovine bone mineral (DBBM), synthetic bone substitutes, and a combination of these materials. The xenogenic bone is frequently used as a comparator biomaterial with many other bone substitutes in the bone research field (Piattelli et al. 1999), and is one of the most widely used scaffolds in dehiscence defects around implants (Berglundh & Lindhe 1997; Hämmerle et al. 1998; Mayfield et al. 2001). Its physical properties are similar to those of human cancellous bone, both in its morphological structure and its mineral composition, presenting
1 INTRODUCTION
Oral rehabilitation with implants has allowed for therapeutic solutions that are unquestionably more advantageous for the patient, as it pertains to function, esthetics and comfort. Insufficient amounts of bone in the implant beds decrease the success rates. Considerable efforts have been made to develop techniques and materials that increase the host bone volume, thus increasing the boneto-implant contact. The most commonly used techniques in clinical practice that promote bone regeneration around exposed implant threads involve the four processes that promote new bone formation: osteogenesis that can be achieved with the use of autogenous human bone (Lang et al. 2003); osteoinduction, creating cell differentiation by means of specific growth factors (GFs) (Misch & Dietsh 1993); osteoconduction, where a grafting material serves as a scaffold for new bone formation (Jensen et al. 1996); and guided bone regeneration (GBR), which allows space maintenance through the use of barrier membranes, into
a good osteoconductivity and biocompatibility (Wetzel et al. 1995).
