title: The ovariectomised sheep as a model for testing biomaterials and prosthetic devices in osteopenic bone: a preliminary study on iliac crest biopsies.
abstract: A histomorphometric and ultrastructural evaluation on sheep iliac bone was performed. Six sheep were ovariectomised (OVX Group) and 6 were left intact (Sham-aged, Control Group). An iliac crest biopsy was performed randomly in 6 animals at the beginning of the study, then, in all the animals, after 12 and 24 months. A significant decrease in trabecular bone volume, trabecular thickness (p<0.0005) and cell volume (p<0.005) was observed in OVX animals. A modest decrease in trabecular number and osteoid thickness together with an increase in trabecular separation were observed in OVX animals at 12 and 24 months. The osteoid volume showed a significant difference (p<0.05) between the groups. In OVX animals, at 12 months, Scanning Electron Microscopy revealed an enlargement of the trabecular space and a progressive replacement of bone matrix with adipose tissue. These signs were accentuated at 24 months. In conclusion, OVX sheep showed a loss of trabecular bone starting at 12 months after ovariectomy. The developed osteopenic state may be considered as a useful tool when doing research on biomaterial osteointegration.
authors.affiliation: Experimental Surgery Department, Rizzoli Orthopaedic Institute, Bologna, Italy. milena.fini@ior.it
authors.forename: M
authors.initials: M
authors.lastname: Fini
authors.forename: G
authors.initials: G
authors.lastname: Pierini
authors.forename: G
authors.initials: G
authors.lastname: Giavaresi
authors.forename: G
authors.initials: G
authors.lastname: Biagini
authors.forename: M M
authors.initials: MM
authors.lastname: Mattioli Belmonte
authors.forename: N
authors.initials: N
authors.lastname: Nicoli Aldini
authors.forename: M
authors.initials: M
authors.lastname: Rocca
authors.forename: L
authors.initials: L
authors.lastname: Martini
authors.forename: R
authors.initials: R
authors.lastname: Giardino
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001672:Biocompatible Materials; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D007085:Ilium / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D016348:Osseointegration; D015663:Osteoporosis, Postmenopausal / Q000473:pathology*; D010052:Ovariectomy; D019736:Prostheses and Implants; D012756:Sheep
chemical_list: D001672:Biocompatible Materials