title: Osteointegration of bioactive glass-coated and uncoated zirconia in osteopenic bone: an in vivo experimental study.
abstract: In elderly and osteoporotic patients an age-related loss of osteoinductivity could be the biological cause of implant failure regardless of the high quality of the implanted device. yttria stabilized tetragonal zirconia (YSTZ), either coated with the bioactive glass named RKKP bioglaze (RKKP) or uncoated, was implanted in the distal femurs of sham-operated and ovariectomized female rats. Animals were sacrificed at 30 and 60 days. Histomorphometry and microhardness tests were performed to assess osteointegration rate as well as bone quality around the implants. Significant decreases (p < 0.0005) in trabecular bone volume, BV/TV (41%), trabecular bone surface BS/TV (33%), trabecular thickness Tb.Th (20%), and trabecular number Tb.N (32%), together with a significant increase in trabecular separation Tb.Sp (184%), were found for the osteopenic rats compared with the sham-operated rats. At both experimental times the RKKP coating ensured a better osteointegration rate with higher AI values than the uncoated YSTZ, even when osteopenic rats were used (48% at 30 days and 12% at 60 days). No differences were observed at the bone-biomaterial interfaces for either material when comparing sham-operated with osteopenic rats. The present results demonstrate that the RKKP bioactive glass used as a coating ensures a high osteointegration rate even in osteoporotic bone, which is already visible from postoperative day 30 and is still apparent on day 60.
authors.affiliation: Experimental Surgery Department, Research Institute Codivilla Putti-Rizzoli Orthopaedic Institute, via di Barbiano 1/10, 40136, Bologna, Italy and University of Bologna Medical School, Bologna, Italy.
authors.forename: N Nicoli
authors.initials: NN
authors.lastname: Aldini
authors.forename: M
authors.initials: M
authors.lastname: Fini
authors.forename: G
authors.initials: G
authors.lastname: Giavaresi
authors.forename: L
authors.initials: L
authors.lastname: Martini
authors.forename: B
authors.initials: B
authors.lastname: Dubini
authors.forename: M G
authors.initials: MG
authors.lastname: Ponzi Bossi
authors.forename: F
authors.initials: F
authors.lastname: Rustichelli
authors.forename: A
authors.initials: A
authors.lastname: Krajewski
authors.forename: A
authors.initials: A
authors.lastname: Ravaglioli
authors.forename: M
authors.initials: M
authors.lastname: Mazzocchi
authors.forename: R
authors.initials: R
authors.lastname: Giardino
mesh_terms: D000818:Animals; D001851:Bone Diseases, Metabolic / Q000601:surgery / Q000628:therapy*; D001861:Bone Regeneration / Q000502:physiology*; D018786:Bone Substitutes / Q000378:metabolism*; D001842:Bone and Bones / Q000378:metabolism*; D020099:Coated Materials, Biocompatible; D005898:Glass; D051381:Rats; D015040:Zirconium
chemical_list: D018786:Bone Substitutes; D020099:Coated Materials, Biocompatible; D015040:Zirconium; C028541:zirconium oxide