Evonik Industries AG researchers are using biodegradable high-strength composites to fix broken bones.
The materials could replace metal implants, which remain in patients' bodies or require surgery for removal. Devices made with Evonik's new composites will be gradually absorbed by the body as the healing process takes place.
The materials consist of polymers and of substances that naturally occur in bones.
The project is being studied at Evonik's Medical Devices Project House in Birmingham, Ala.
“In the long term, our focus is regenerative medicine. We want to create bioabsorbable implants to replace damaged tissues with healthy tissues. Our current work on biodegradable composites is a first step in this direction,” said Dr. Andreas Karau, head of the Project House, in a news release.
“Our leading position in polylactic acid-based polymers is an excellent foundation for the development of materials and solutions for regenerative medicine,” Karau said. The polymers break down into carbon dioxide and water. Degradation time depends on the molecular composition, chain length, and crystallinity.
Evonik's Resomer polymers are currently used in bioabsorbable screws, pins and small plates, primarily for torn ligaments, and for fixing smaller bones in fingers or the face.
“At the moment, the materials we have available are not strong enough to be used for large, load-bearing bones,” Karau said.
Researchers are exploring composites that reinforce biodegradable polymers with inorganic substances, such as derivatives of calcium phosphate. The additives may strengthen the material and enhance its biocompatibility.
“As the polymers gradually break down, calcium and phosphate can be absorbed into the newly formed bone tissue,” Karau said.
He added that a goal of the researchers is to make biodegradable polymers suitable for 3-D printing.
The Project House is part of Evonik's Creavis strategic innovation unit, and in this case the researchers are working with polymer specialists from the company's Health Care and Performance Materials businesses. Project Houses typically concentrate on a defined field for three years, collaborating with multiple business units. Since 2000, Essen,Germany-based Evonik has established a total of 11 Project Houses.