The restoration of skeletal function remains an important challenge in a wide range of fields including orthopedics, neurosurgery, and dentistry. Over two million bone graft procedures are performed annually, with five hundred thousand in the United States alone. Despite advances in bone regeneration over the last twenty years, there is a need for a new material that encourages natural replacement without the addition of living cells and other growth factors. The new material must also include biodegradable properties so the body can heal and restore itself in order to limit post-surgical complications. Researchers at the University of Nebraska-Lincoln recently described in Science Advances a new material that may prove to be effective for bone repair that requires either added cells or growth factors.
Two forms of the new material were compared that differ in the alignment of tiny channels through which cells may migrate.
In one form, the channels are aligned horizontally with respect to the bone lesion. In the other, the channels are assigned vertically. The fibers are made from a biodegradable polyester coated with gelatin to promote gradual reabsorption of bone in eighteen to twenty-four months.
The fundamental experiment in this study explores whether horizontal or vertical alignment of fibers is best for bone regeneration. In general, both forms of positioning allow for cells to properly migrate and deposit collagen as needed. Both placement techniques regenerated bone superior to that of the control hydrogel used in this experiment.
Both also led to the formation of a bilayer of highly calcified bone surrounding a spongy interior. To the researcher’s surprise, however, the vertically aligned fibers were more durable than the horizontal fibers. See below Figure 4, 5, and 6.
The researchers are now planning to test their material on larger bone lesions. Lead researcher on the project, Jingwei Xie, stated, “We’re still trying to optimize the structure. Right now, it can enhance bone regeneration, but I think we still can improve it in certain ways.” Dr. Xie also plans to test their implants on the repair of the femur, tibia, and clavicle.