Patients who suffer loss of jaw bone are left with bony defects that are both aesthetically and functionally challenging. Researchers from Rice University in the United States have developed a technique to generate engineered tissue customised to specific defects by implanting a 3D-printed bioreactor against a rib. The stem cells and blood vessels from the rib grow a natural bone material that is tailored to the patient and can be transplanted to the face.

The goal of the research was to advance craniofacial reconstruction by taking advantage of the body’s natural healing powers. The technique has been developed to replace current reconstruction techniques that use autogenous bone graft tissue.

“A major innovation of this work is leveraging a 3D-printed bioreactor to form bone grown in another part of the body while we prime the defect to accept the newly generated tissue,” said co-author Dr Antonios Mikos, Louis Calder Professor of Bioengineering and Chemical and Biomolecular Engineering at the university.

The researchers made a rectangular defect in the jaw bones of sheep. They created a template for 3D printing and printed an implantable mould and a spacer, both made of bone cement. The goal of the spacer was to promote healing and prevent scar tissue from filling the defect site.

The mould stayed in place for nine weeks before removal and transfer to the site of the defect, replacing the spacer. In the animal models, the new bone knitted to the old and soft tissue grew around and covered the site.