Authors: O Erdemli O Çaptug H Bilgili D Orhan A Tezcaner D Keskin
Publish Date: 2009/09/16
Volume: 21, Issue: 1, Pages: 295-308
Abstract
The objective of this study was to improve the efficacy of polycaprolactone/bioglass PCL/BG bone substitute using demineralized bone matrix DBM or calcium sulfate CS as a third component Composite discs involving either DBM or CS were prepared by compression moulding Bioactivity of discs was evaluated by energy dispersive Xray spectroscopy ESCA and scanning electron microscopy SEM following simulated body fluid incubation The closest Calcium/Phosphate ratio to that of hydroxyl carbonate apatite crystals was observed for PCL/BG/DBM group 153 after 15 day incubation Addition of fillers increased microhardness and compressive modulus of discs However after 4 and 6week PBS incubations PCL/BG/DBM discs showed significant decrease in modulus from 26623 to 5404 and 3345 MPa respectively in parallel with its highest water uptakes 363 and 347 Discs preserved their integrity with only considerable weight loss 75–145 in PCL/BG/DBM group In vitro cytotoxicity tests showed that all discs were biocompatible Composites were implanted to defects on rabbit humeri After 7 weeks new tissue formation and mineralization at boneimplant interface were observed for all implants Bone mineral densities at interface were higher than that of implant site and negative controls defects left empty but lower than healthy bone level However microhardness of implant sites was higher than in vitro results indicating in vivo mineralization of implants Addition of DBM or CS resulted with higher microhardness values at interface region ca 650 μm from implant compared to PCL/BG and negative control Histological studies revealed that addition of DBM enhanced bone formation around and into implant while CS provided cartilage tissue formation around the implant From these results addition of DBM or CS could be suggested to improve bone healing efficacy of PCL/BG composites
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