Russian researchers have suggested a new technique for accelerating healing of damaged and broken bones. The “magic” substance, used for this purpose, is called fibrin.

Fibrin is a protein, synthesized by an organism, when its system of blood coagulation gets activated. Fibrin fibers form a clot skeleton, thus protecting injured place from blood loss and from infection spread. Fibrin clots are widely used in medical practice – for bleeding control after tooth extraction in dentistry, for instance. However, information whether these clots are able to enhance bone tissue regeneration, is rather scarce. That is why biochemists and medics from Novosibirsk tried to find out whether fibrin really worked for faster bone regeneration.

The experiment was held on laboratory rats with artificially damaged bones of lower jaw. Medics consider best therapeutic effect to form, when fibrin clots used for therapy are made from a patient’s blood. However, in the experiments with rats, fibrin clots belonged to rats other, than those, which participated in the research; however, all rats belonged to one line and were genetically very close.

Researchers worked with rats’ lower jawbone, which is a wide and strong bone, easy to work with. Another reason for choosing this bone is that rats aren’t able to get rid of stitches. Scientists made a round hole in these bones – using anesthesia, of course. Half of animals received a fibrin clot in their injury – this was a test group. Each week during a 5-week period, bones of rats were analyzed by means of light microscopy and X-ray examination.

 

 

After one week, holes in a lower jawbone of rats without the fibrin clot were filled with blood, and the injury’s margins contained fragments of a loose connective tissue. After two weeks, control group showed full coverage of the injury with cartilaginous tissue. In three weeks a new bone formed with only some signs of an injury. Fourth and fifth weeks brought almost full recovery from the injury.

As for rats, which bone injury was covered with a fibrin clot, early recovery stages appeared to be shorter – fragments of a new bone appeared as soon as in one week. Examinations of the test group of laboratory rats in two, three, four and five weeks after treatment showed similar recovery pattern as shown for rats from the control group. Researchers demonstrated that bones with fibrin clots recovered faster, than bones without any treatment – full recovery was detected in two weeks with fibrin, and in three weeks without fibrin.

A fibrin clot soothes an inflammation process, which starts in an injury. Moreover, this clot serves as a skeleton, which helps immune cells, as well as connective tissue cells, to move along the clot. Researchers, who showed that new bone formed faster with fibrin treatment, explain this phenomenon with formation of a new bone starting right after fibrin introduction – without losing time for lysis and removal of a blood clot with large amount of erythrocytes.