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Degradation rates of polymers and copolymers of polylactic and polyglycolic acids

1974; Elsevier BV; Volume: 37; Issue: 1 Linguagem: Inglês

10.1016/0030-4220(74)90171-6

1878-2175

Duane E. Cutright, Bienvenido Perez, Joe D. Beasley, Wayne J. Larson, William R. Posey,

Graphene and Nanomaterials Applications

This study has substantiated the following previously reported characteristics of these polymers and copolymers: They are biodegradable. The degradation is accomplished by capillary ingrowth and/or phagocytic foam cells. The degradation is not accompanied by inflammation. The pellets are replaced by fibrous connective tissue and/or bone and marrow tissue. Bone is deposited directly upon and within these materials, thus providing good continuing stabilization. Furthermore, this study has established that, by varying the proportions of PLA to PGA, resorption times can be varied from less than 100 days to periods in excess of 220 days. These materials degrade in the following order: 25 per cent PLA degrades first; 50 per cent PLA degrades second; 75 per cent PLA degrades third; 100 per cent PLA degrades fourth; 100 per cent PGA degrades the slowest. The fast-cooled and slow-cooled polymers with different crystal formations do not affect the degradation rates. The ranges of resorption encompass the times required for fracture fixation. Studies are presently in progress on other proportions of these polymers and on different polymers.