The poly (L-co-DL lactic acid) copolymer, PLDLA, has achieved outstanding position in the temporary prostheses because its degradation life is up to goog extent compatible with the requirement for the bone fracture repair. In vitro degradation of the in- Lab synthesized PLDLA was studied. The PLDLA plates were immersed in a phosphate buffer solution with pH = 7,4 at 37ºC +- 1º C provided by a thermostat controlled bath for specified test times (2, 4, 8, 16 and 30 weeks) and evaluated by using the following techniques: gel permeation chromatography (GPC), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and three point flexural strength test. From in vitro test, it was found that change in the PLDLA molecular weight due to its degradation is already noticeable since the second test-week. The initially amorphous PLDLA presented traces of cristalline signs according to DSC curves, while the thermal stability of the copolymer is affected only after 16 test-weeks as shown by TGA results. The change of PLDLA pieces from dense to porous took 18 in-vitro test-weeks as revealed by SEM. After four test months, PLDLA was capable of retaining more than 80% of its original three-point flexural strengh, which is up to good extent compatible with the requirements for bone consolidation.
synthesis; PLDLA; in vitro degradation
