title: Frictional properties of regenerated cartilage in vitro.
abstract: Although tribological function is the most important mechanical property of articular cartilage, few studies have examined this function in tissue-engineered cartilage. We investigated changes in the frictional properties of cartilage regenerated from the inoculation of rabbit chondrocytes into fibroin sponge. A reciprocating friction-testing apparatus was used to measure the friction coefficient of the regenerated cartilage under a small load. The specimen was slid against a stainless steel plate in a water vessel filled with physiological saline. The applied load was 0.03 N, the stroke length was 20 mm, and the mean sliding velocity was 0.8 mm/s. The friction coefficient of the regenerated cartilage decreased with increasing cultivation time, because a hydrophilic layer of synthesized extracellular matrix was formed on the fibroin sponge surface. The friction coefficient of the regenerated cartilage was as low as that of natural cartilage in the early stages of the sliding tests, but it increased with increasing duration of sliding owing to exudation of interstitial water from the surface layer.
authors.affiliation: Department of Electronics, Information and Communication, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585, Japan. morita@elc.oit.ac.jp
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Morita
authors.forename: Naohide
authors.initials: N
authors.lastname: Tomita
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Aoki
authors.forename: Masato
authors.initials: M
authors.lastname: Sonobe
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Wakitani
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tamada
authors.forename: Toru
authors.initials: T
authors.lastname: Suguro
authors.forename: Ken
authors.initials: K
authors.lastname: Ikeuchi
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000502:physiology* / Q000648:ultrastructure; D019902:Chondrocytes / Q000502:physiology* / Q000648:ultrastructure; D004548:Elasticity; D005349:Fibroins / Q000737:chemistry; D017276:Friction; D006025:Glycosaminoglycans / Q000378:metabolism; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011817:Rabbits; D012038:Regeneration / Q000502:physiology*; D013314:Stress, Mechanical; D023822:Tissue Engineering; D014783:Viscosity
chemical_list: D006025:Glycosaminoglycans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D005349:Fibroins