title: [Prolonged inflammatory reactions induced by ceramic powders in the rat air pouch model].
abstract: The subcutaneous air pouch of the male Sprague-Dawley rat was used to study inflammatory potential of artificial ceramics. Local leukocyte influx, proteinase, prostaglandin E2 (PGE2) and tumor necrosis factor (TNF) levels were measured after injection of hydroxyapatite ceramic (HAP), tricalcium phosphate ceramic (TCP) and apatite-wollastonite glass ceramic (GC) into the pouch. Synthetic monosodium urate crystals (MSU) were used as positive controls and normal saline (NS) as a negative control. The response was monitored over a period of 168 hours by irrigating the pouch with 5 ml of NS and withdrawing 4 ml. MSU produced the greatest response in leukocyte counts, proteinase and PGE2, whereas HAP, TCP and GC often appeared later than with MSU. TNF was significantly detected only after ceramics and not after MSU. The chronic and relatively prolonged reaction to HAP, TCP and GC suggests that an inflammatory reaction may occur after implantation of these ceramics in humans. The increased levels of TNF and production of PGE2, which are substances proposed to contribute to osteolysis associated with loosening, are of special interest for further research.
authors.affiliation: Department of Orthopaedic Surgery, Gunma University School of Medicine, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Nagase
authors.forename: E
authors.initials: E
authors.lastname: Udagawa
authors.forename: H R
authors.initials: HR
authors.lastname: Schumacher
authors.forename: D G
authors.initials: DG
authors.lastname: Baker
mesh_terms: D000818:Animals; D002516:Ceramics / Q000009:adverse effects*; D015232:Dinoprostone / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism; D007249:Inflammation / Q000175:diagnosis / Q000209:etiology*; D007958:Leukocyte Count; D008297:Male; D011208:Powders; D019736:Prostheses and Implants; D011475:Prosthesis Failure; D051381:Rats; D011919:Rats, Inbred Strains; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D011208:Powders; D014409:Tumor Necrosis Factor-alpha; D010450:Endopeptidases; D015232:Dinoprostone