[Bond strength of a bioresorbable bone adhesive: results of a biomechanical study in a sheep model]

The purpose of this study was to investigate the bond strength of a new bone adhesive based on ethylene glycol-oligolactide-bismethacrylate on 36 sheep. A 2-cm metaphysial segment was produced on the ulna of each sheep by an oscillating saw and it was not stabilized by any type of additional osteosynthesis. Adhesive was applied to the osteotomy gaps in 18 sheep, the remaining 18 animals served as controls. A total of 6 animals with glue and 6 controls were euthanized after 21, 42 and 84 days. The bond strength after repair of the gaps through bone adhesive compared to a control group was studied by using a four-point bending test. There was a continual increase of bending stiffness from 21 to 84 days in all sheep, with the highest bending stiffness of 102.83 N/mm2 by the glue group after 84 days as opposed to the control group with 58.48 N/mm2 (p = 0.25). Morphological investigations showed more callus formation by the control group than the adhesive group after 84 days (p = 0.04). In addition, an in vitro gluing of the ulna segment was performed with a four-point bending test after 10, 60 and 360 min polymerization time. The in vitro gluing of the ulna segment showed a continual increase of bending stiffness to 17.32 N/mm2 after 360 min (p = 0.59).