Studies on poly(propylene fumarate-co-ethylene glycol) based bone cement.

Poly(propylene fumarate-co-ethylene glycol) random (PPF-1) and block (PPF-2) copolymer oligomers were prepared. Comparing the setting characteristics of PPF-1 and PPF-2 with comonomer n-vinyl pyrrolidone (n-VP) and swelling characteristics of cured PPF-1 and PPF-2, lower setting temperature and setting time was observed with the former leading to higher swelling coefficient and lower cross link density in the cured PPF-1. Due to the high swelling coefficient and low setting exothermic temperature associated with PPF-1, the bone cement was prepared from PPF-1, n-VP and hydroxyapatite (HAP). The in vitro degradation studies reveal lesser weight loss and deformation of PPF-1/n-VP/HAP based cured resin in Ringer's solution and phosphate buffered saline in comparison with that of PPF-1/n-VP cured resin. Though the bone cement composite has adequate mechanical properties with HAP, the compressive strength and modulus of the composite aged in Ringer's solution and PBS reduced appreciably which is due to extensive hydration and plasticization by the PEG unit. However, the bone-binding and bond strength of the bone cement determined as the load for separation of bones was found to be similar to that of fast setting calcium phosphate-atelocollagen (5%) bone cement. The bone cement PPF-1/n-VP/HAP could be used as scaffold for correcting the bone defects.