Scratch assays were performed as a model for wounding on dishes and Ti disks with or without treatment. In a confluent monolayer of OECs that had been serum-starved in DMEM for 6 h, a scratch was made with a cell scraper. The width of the scratch was measured at the beginning and after 3 days or 6 days of culturing in DMEM with 0.5% serum. OECs at the edge of the wound were observed by SYTO 9 staining for cell visualization. Relative closure was calculated by dividing the different group wound closures by that of the blank group.