title: A comparison of different nanostructured biomaterials in subcutaneous tissue.
abstract: The nanostructured surface of a material can improve its interaction with cells and its acceptance as an implant. We compared two novel biomaterials with different nanostructures: Bioverit II with a coating of nanoporous silica and chitosan-hydroxyapatite composite materials. Pure Bioverit II served as a control. Platelets of these materials were implanted for 28, 85 and 300 days in the subcutaneous tissue in the neck of 38 rabbits. After excising the specimens they were fixed, embedded in epoxy resin and analyzed histologically. All coated Bioverit II implants showed a thin capsule of connective tissue. After 300 days, these capsules tended to be thicker than in pure Bioverit II. No signs of inflammation were observed and the materials appeared unaltered by visual inspection. In case of chitosan-hydroxyapatite composites, massive capsules consisting of dense connective tissue were found, and the material showed signs of biodegradation in form of fissures and cavities. In conclusion, the nanoporous coating showed no obvious positive effect with regard to capsule formation; the chitosan-hydroxyapatite implants provoked a stronger interaction between cells and material. However, most Bioverit II implants showed no alterations optically, whereas chitosan-hydroxyapatite was partly degraded in all cases.
authors.affiliation: Department of Otolaryngology, Medical School Hannover, Germany.
authors.forename: Julia C
authors.initials: JC
authors.lastname: Vogt
authors.forename: Gudrun
authors.initials: G
authors.lastname: Brandes
authors.forename: Ilka
authors.initials: I
authors.lastname: Krüger
authors.forename: Peter
authors.initials: P
authors.lastname: Behrens
authors.forename: Ingo
authors.initials: I
authors.lastname: Nolte
authors.forename: Thomas
authors.initials: T
authors.lastname: Lenarz
authors.forename: Martin
authors.initials: M
authors.lastname: Stieve
mesh_terms: D000818:Animals; D002516:Ceramics / Q000009:adverse effects*; D048271:Chitosan / Q000009:adverse effects*; D020099:Coated Materials, Biocompatible / Q000009:adverse effects; D003238:Connective Tissue / Q000187:drug effects* / Q000473:pathology* / Q000601:surgery; D017886:Durapatite / Q000009:adverse effects*; D005260:Female; D005549:Foreign-Body Reaction / Q000209:etiology* / Q000473:pathology*; D008422:Materials Testing; D049329:Nanostructures / Q000009:adverse effects; D019736:Prostheses and Implants / Q000009:adverse effects*; D011817:Rabbits
chemical_list: C067324:Bioverit; D020099:Coated Materials, Biocompatible; D048271:Chitosan; D017886:Durapatite