Effect of Surface Texture of a Polyimide Porous Membrane on the Bone Formation Rate

抄録

The surface texture of implant materials affects their clinical performance, but the fundamental mechanisms by which tissues sense differences in the surface characteristics of materials are unclear. In this study, we applied a novel polyimide double-faced porous membrane with openings of different sizes on each side to a rat calvarial bone regeneration model and, using CT and histological methods, evaluated the bone formation rate in the direction of the transplant membrane. The tissue around the membrane reacted asymmetrically, with a different rate of bone formation depending on the direction of the implant membrane. When the bone defect faced the side of the membrane with small openings (10-30 µm aperture), bone formation indices, such as the bone mineral density, bone mineral content, and bone volume, changed more rapidly compared with those when the bone defect faced the membrane side with large openings (40-60 µm) during the early stage of bone regeneration. Our results suggest that cells detected the difference in membrane surface texture and changed their behavior accordingly to accelerate bone regeneration. We believe that the manipulation of the surface texture of implant materials is important for improving medical applications in bioengineering.