title: Biological performance of a new beta-TCP/PLLA composite material for applications in spine surgery: in vitro and in vivo studies.
abstract: The objective of this research was to carry out an in vitro and in vivo study of the biological performance of PLLA/beta-TCP composite materials, to estimate the scope of their potential applications in bone surgery. Samples with increasing beta-TCP (0-60% w/w) contents were processed by injection molding. The in vitro study consisted of an evaluation of inflammatory potential by assaying the IL-1alpha secreted by monocytes, and then cell proliferation (counting) and phenotype expression (PAL and I collagen) in human osteogenous cells. The in vivo study was carried out using cylindrical implants of composite materials composed of composite materials containing 0 or 60% beta-TCP and pure beta-TCP, respectively. The implants were inserted in femoral sites in rabbits, using the Kathagen protocol. Each animal received a 60% implant, with either a 0 or a 100% implant in the contralateral femur, so that the materials could be compared with one another. Five animals were examined for each material and implantation period, giving a total of 30 animals. This study showed that adding increasing percentages of beta-TCP to a lactic acid polymer matrix stimulated the proliferation of human osteogenous cells and synthesis of the extracellular bone matrix in a dose-dependent manner. In vivo results indicate that, in comparison with pure PLA, tricalcium phosphate-containing composite materials had faster degradation kinetics, caused less inflammatory reaction, and promoted contact osteogenesis. The composite material containing 60% beta-TCP demonstrated a similar performance to pure tricalcium phosphate bone grafts in terms of osteogenesis, and is apparently compatible with the production of intra-osseous implants for situations representing high levels of mechanical strain.
authors.affiliation: Bordeaux 2 University, Spine Unit, 6th Floor, DETERCA Lab, 146 Leo Saignat, Bordeaux 33076, France.
authors.forename: Stephane
authors.initials: S
authors.lastname: Aunoble
authors.forename: Denis
authors.initials: D
authors.lastname: Clément
authors.forename: Patrick
authors.initials: P
authors.lastname: Frayssinet
authors.forename: Marie Francois
authors.initials: MF
authors.lastname: Harmand
authors.forename: Jean Charles
authors.initials: JC
authors.lastname: Le Huec
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D002130:Calcium Phosphates / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism; D019344:Lactic Acid / Q000494:pharmacology*; D009000:Monocytes / Q000378:metabolism; D010011:Osteocytes / Q000166:cytology* / Q000187:drug effects; D010012:Osteogenesis; D011091:Polyesters; D011108:Polymers / Q000494:pharmacology*; D019736:Prostheses and Implants; D011817:Rabbits; D013131:Spine / Q000601:surgery*; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; D007375:Interleukin-1; D011091:Polyesters; D011108:Polymers; C485817:beta-tricalcium phosphate; D019344:Lactic Acid; C033616:poly(lactide)