Prefabricated bone flap: an experimental study comparing deep-frozen and lyophilized-demineralized allogenic bones and tissue expression of transforming growth factor β

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

ABSTRACT

The aim of this study was to conduct a biomechanical analysis of the early period bone-implant connection of titanium implants in the same type of subjects. In this study, 18 Sprague Dawley rats were used. Four rats were killed to provide the allogeneic bone before the experiment, and the remaining were divided into a control group and an experimental allogeneic bone transfer group. Titanium machined surfaced implants were integrated in tibias in the controls and in the experimental group; simultaneously, implants were integrated into allogeneic bone in the bone transfer group. All the rats were sacrificed 14 days later. Bone tissues with titanium implants were removed for biomechanical analysis, which found that the resistance to force of the control group and the allogeneic graft group was 2.04 and 2.00 Newtons, respectively, and there was no significant difference between the two groups at 14 days, although numerically a higher figure was detected in the controls (P > 0.05). It was concluded, within the limitations of this study, that an allogeneic bone transfer can be used as an alternative to an autogenous graft.

Bone Graft Prefabrication Following the In Vivo Bioreactor Principle

Large bone defect treatment represents a great challenge due to the difficulty of functional and esthetic reconstruction. Tissue-engineered bone grafts created by in vitro manipulation of bioscaffolds, seed cells, and growth factors have been considered potential treatments for bone defect reconstruction. However, a significant gap remains between experimental successes and clinical translation. An emerging strategy for bridging this gap is using the in vivo bioreactor principle and flap prefabrication techniques. This principle focuses on using the body as a bioreactor to cultivate the traditional triad (bioscaffolds, seed cells, and growth factors) and leveraging the body's self-regenerative capacity to regenerate new tissue. Additionally, flap prefabrication techniques allow the regenerated bone grafts to be transferred as prefabricated bone flaps for bone defect reconstruction. Such a strategy has been used successfully for reconstructing critical-sized bone defects in animal models and humans. Here, we highlight this concept and provide some perspective on how to translate current knowledge into clinical practice.

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The in vivo bioreactor principle and flap prefabrication technique is a promising strategy for bone defect reconstruction.

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The in vivo bioreactor principle focuses on using the body’s self-regenerative capacity to regenerate new tissue.

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This strategy has been successfully used to reconstruct critical-sized bone defects in humans.