Potential of autogenous or fresh-frozen allogeneic bone block grafts for bone remodelling: a histological, histometrical, and immunohistochemical analysis in rabbits

Abstract

Our aim was to compare the wound healing of autogenous bone grafts with that of fresh-frozen allogeneic block bone in rabbits. We used 25 animals. One was killed before the experiment to provide the allogeneic bone, and the remainder were killed at four time points (n=6 in each group). On histometrical analysis there was a significant difference between the two groups only at 45days and between 15 and 45days in the intergroup analysis. However, there was significantly more revascularisation (p<0.05), resorption (p<0.05), and bony replacement (p<0.05) in the autogenous group in the immunohistochemical analysis. In later periods, the autogenous bone was replaced by newly-formed bone in all samples, whereas it was always possible to find regions of devitalised bone in the fresh-frozen allogeneic bone grafts. Autogenous grafts were completely replaced whereas, in the fresh- frozen allogeneic grafts, we found acellular tissue that had been incorporated into the receptor bed interface during the later evaluation times.

Horizontal Alveolar Ridge Augmentation with Allogeneic Bone Block Graft Compared with Autogenous Bone Block Graft: a Systematic Review

“…Moreover, a randomized controlled trial assessing HARA with FFA compared with autogenous bone block revealed new bone formation with both treatment modalities, but FFA demonstrated clear signs of inflammation [20]. Similar healing patterns have been observed in an experimental study demonstrating statistically significant greater revascularization and bony replacement after HARA with autogenous bone block compared with allogeneic bone block [63].…”

“…Autogenous bone block was replaced by newly formed bone, whereas regions of non-vital bone were seen after HARA with allogeneic bone block [63]. Consequently, both treatment modalities seem to facilitate new bone formation.…”

Osseointegration Levels of Implants Placed With Allogenic and Xenogenic Bone Ring: An Experimental Biomechanical Analysis

“…Junior and colleagues reported that dehiscence may occur on the implant surface even after a lengthy healing period due to nonvascularized tissue areas supported by allogenic grafts. They also suggested that complete revascularization is never possible in allogenic block grafts, and even after a long time, necrotic areas may be present at the application site 31. In a study, implants were followed for 30 to 35 years, and allograft was preferred as the graft material for bone defects.…”

Biomechanical Examination of Osseointegration of Titanium Implants Placed Simultaneously With Allogeneic Bone Transfer

“…In another study in animal, when they compared the allogeneic block graft with the autogenic block graft, they reported that there were necrotic areas in the allogeneic group even after 180 days, which may be due to the delay in the first revascularization, but the autogenic group was completely revascularized after 180 days and there were no necrotic areas. Junior et al 13 also reported that the necrotic, non-vascularized tissue areas in their implants supported by allogeneic graft may create conditions for the formation of bone sequestration areas later, and may cause openings on the surface of the implant even after a long period of application, and complete removal of the block graft will be required. In addition, they suggest that the allogeneic block graft can never be completely revascularized and necrotic areas will remain even after a long time.…”