title: Effects of hydrofluoric acid and anodised micro and micro/nano surface implants on early osseointegration in rats.
abstract: Our aim was to evaluate the effects of hydrofluoric acid and anodised micro and micro/nano surface implants on bony ingrowth in the earliest stage of implantation in rats. Sixty cylindrical screwed titanium alloy implants with machined, micro, and hierarchical hybrid micro/nano surfaces (n=20 in each group) were inserted into the distal femurs of 30 female Sprague-Dawley rats. In vivo microcomputed tomography (micro CT) was used to assess microarchitectural changes in the bone around the implants 2 weeks after implantation. All the animals were then killed and the femurs with implants harvested for histological analysis and pull-out testing. Micro CT analysis showed that the trabecular thickness and the bone:volume ratio (bone volume:total volume) (BV:TV) increased significantly in the micro/nano group compared with the other two groups, while the trabecular separation decreased significantly in the micro/nano group compared with the machined group. The mean (SD) bone-implant contacts (%) were 38.94 (9.48), 41.67 (8.71), and 51.49 (12.49) in the machined, micro, and micro/nano groups, respectively. The maximum pull-out forces (N) were 64.95 (6.11), 71.45 (7.15), and 81.90 (13.1), respectively. Both bone-implant contacts and maximum pull-out forces were significantly higher in the micro/nano group, but there was no significant difference between the micro group and the machined group. These data indicate that the hierarchical hybrid micro/nano surface of the implant can promote osseointegration in the earliest stage of implantation, and may be a promising option for further clinical use.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Stomatology, the Fourth Military Medical University, 145 West Changle Road, Xi'an 710032, Shaanxi, China.
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Li
authors.forename: Yuan
authors.initials: Y
authors.lastname: Gao
authors.forename: Bo
authors.initials: B
authors.lastname: Shao
authors.forename: Jianrui
authors.initials: J
authors.lastname: Xiao
authors.forename: Kaijin
authors.initials: K
authors.lastname: Hu
authors.forename: Liang
authors.initials: L
authors.lastname: Kong
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D005260:Female; D006858:Hydrofluoric Acid / Q000737:chemistry / Q000494:pharmacology*; D020007:Implants, Experimental; D008422:Materials Testing / Q000379:methods*; D053758:Nanoparticles / Q000627:therapeutic use* / Q000648:ultrastructure; D016348:Osseointegration / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013499:Surface Properties; D014025:Titanium; D055114:X-Ray Microtomography
chemical_list: D014025:Titanium; D006858:Hydrofluoric Acid