Material properties of absorbable self-reinforced fibrillated poly-96L/4D-lactide (SR-PLA96) rods; a study in vitro and in vivo

Citation
A. Saikku-backstrom et al., Material properties of absorbable self-reinforced fibrillated poly-96L/4D-lactide (SR-PLA96) rods; a study in vitro and in vivo, J MAT S-M M, 10(1), 1999, pp. 1-8
Citations number
44
Categorie Soggetti
Multidisciplinary
Journal title
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE
ISSN journal
09574530 → ACNP
Volume
10
Issue
1
Year of publication
1999
Pages
1 - 8
Database
ISI
SICI code
0957-4530(199901)10:1<1:MPOASF>2.0.ZU;2-N
Abstract
A study was carried out to investigate changes in mechanical properties and degradation of self-reinforced fibrillated poly-96L/4D-lactide (SR-PLA96) rods in vitro and in vivo. The viscosity-average molecular weight, M-v, of the intact sterile (gamma irradiated) rods was around 50 000 g mol(-1). The SR-PLA96 rods of diameter 1.1 mm by 30 mm and diameter 4.5 mm by 50 mm wer e immersed in phosphate-buffered saline or implanted in the dorsal subcutis of rabbits. Bending, shear and torsion strength and bending modulus, toget her with the changes of viscosity and crystallinity, were measured up to 24 wk. The strength values showed only a slight decrease during the follow-up period with the exception of torsion strength, that decreased to 52% of th e initial value during 24 wk. There were no statistically significant diffe rences in the strength retention between in vitro and in vivo groups. Cryst allinity increased over time, being 46-49% at 24 wk. The M-v of the rods de creased over 50% by 24 wk. These promising results motivated us to continue the studies with the fixation of experimental cortical bone osteotomies wi th SR-PLA96 intramedullary rods. (C) 1999 Kluwer Academic Publishers.