Bone Healing in the Presence of a Biodegradable PBS-DLA Copolyester and Its Composite Containing Hydroxyapatite

The healing process of the fractured bone in a presence of poly(butylene succinate-butylene dilinoleate) (PBS-DLA) copolymer containing nanosized hydroxyapatite (HAP) particles has been investigated. The PBS-DLA material containing PBS hard segments and DLA soft segments (50:50 wt %) was used to prepare a polymer/ceramic composite with 30 wt % HAP. A new PBS-DLA copolymer showed a high elasticity of 500% and 15 MPa tensile strength. Addition of HAP improved tensile strength up to 25 MPa while high elasticity has been preserved going down only to 300% of elongation at break. A polymer nanocomposite was fabricated into small elastic polymer rods 15 mm long and 1 × 2 mm in cross section and used for tibia bone fixation in rats. Mallory trichrome staining indicated that new biodegradable copolymers and its composite containing HAP have triggered the most advanced bone healing of all tested materials, thus indicating their high potential for bone tissue engineering and repair.