In vitro effect of a corrosive hostile ocular surface on candidate biomaterials for keratoprosthesis skirt.
OBJECTIVE
Keratoprosthesis (KPro) devices are prone to long-term corrosion and microbiological assault. The authors aimed to compare the inflammatory response and material dissolution properties of two candidate KPro skirt materials, hydroxyapatite (HA) and titania (TiO(2)) in a simulated in vitro cornea inflammation environment.


METHODS
Lipopolysaccharide-stimulated cytokine secretions were evaluated with human corneal fibroblasts on both HA and TiO(2). Material specimens were subjected to electrochemical and long-term incubation test with artificial tear fluid (ATF) of various acidities. Topography and surface roughness of material discs were analysed by scanning electron microscopy and atomic force microscopy.


RESULTS
There were less cytokines secreted from human corneal fibroblasts seeded on TiO(2) substrates as compared with HA. TiO(2) was more resistant to the corrosion effect caused by acidic ATF in contrast to HA. Moreover, the elemental composition of TiO(2) was more stable than HA after long-term incubation with ATF.


CONCLUSIONS
TiO(2) is more resistant to inflammatory degradation and has a higher corrosion resistance as compared with HA, and in this regard may be a suitable material to replace HA as an osteo-odonto-keratoprosthesis skirt. This would reduce resorption rates for KPro surgery.
Tissue Engineering and Stem Cell Research Group, Singapore Eye Research Institute, Singapore.
Xiao Wei
XW
Tan
Andri
A
Riau
Zhi Long
ZL
Shi
Anna C S
AC
Tan
Koon Gee
KG
Neoh
Khiam Aik
KA
Khor
Roger W
RW
Beuerman
Donald
D
Tan
Jodhbir S
JS
Mehta
D000143:Acids / Q000494:pharmacology; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology*; D002478:Cells, Cultured; D003316:Corneal Diseases / Q000601:surgery; D060527:Corneal Keratocytes / Q000187:drug effects* / Q000473:pathology / Q000648:ultrastructure; D003343:Corrosion; D003481:Cuspid / Q000637:transplantation; D017886:Durapatite / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D009883:Ophthalmic Solutions / Q000494:pharmacology; D019736:Prostheses and Implants; D019651:Plastic Surgery Procedures / Q000379:methods; D014025:Titanium / Q000737:chemistry / Q000494:pharmacology*
D000143:Acids; D001672:Biocompatible Materials; D009883:Ophthalmic Solutions; C009495:titanium dioxide; D017886:Durapatite; D014025:Titanium