Researchers at the University of California Los Angeles School of Dentistry say they have developed the first adhesive hydrogel designed specifically to regenerate bone and tissue defects following head and neck surgeries. Their invention was inspired in part by the way marine mussels can stick to wet surfaces, they add.
Surgeons and clinicians have begun using hydrogels over the past few years to administer therapeutic drugs and stem cells to help regenerate lost tissues and bone defects. This approach has advantages over the previous standard treatment, bone grafts, which can lead to inflammation and infection as well as be costly.
Made of networks of polymers, hydrogels can effectively carry drugs and stem cells to targeted spots in the body. But they’re less effective when used in oral surgeries because blood and saliva prevent them from properly adhering to surgical sites. The drugs or stem cells they carry, then, don’t stay in place long enough to deliver their regenerating and therapeutic properties.
“We knew that we needed a product that had optimal adhesion within the confines of the mouth or else our goal to effectively regenerate bone and tissue in the oral cavity would fail,” said Dr. Alireza Moshaverinia, assistant professor of prosthodontics and corresponding author of the study.
Inspired by mussels’ natural ability to adhere to surfaces underwater, the researchers modified their hydrogel by applying an alginate-based solution. Alginates are found in the cells of algae and, when hydrated, form a sticky, gum-like substance.
The researchers tested their new hydrogel, loaded with stem cells taken from gum tissue and bone-building bioactive ceramics, in an 18-week study on rats with a version of peri-implantitis. By the end of the study, the bone around the implants in all of the rats had completely regenerated.
The scientists injected the hydrogel in the mouth and, to seal it in place, applied a light treatment similar to the method that dentists use in human beings to solidify dental fillings.
“The light treatment helped harden the hydrogel, providing a more stable vehicle for delivery of the stem cells,” Moshaverinia said. “We believe that our new tissue engineering application could be an optimal options for patients who have lost their hard and soft craniofacial tissues due to trauma, infection, or tumors.”
The study, “An Engineered Cell-Laden Adhesive Hydrogel Promotes Craniofacial Bone Tissue Regeneration in Rats,” was published by Science Translational Medicine.