Purpose To report experience in the treatment of persistent corneal epithelial defect using overnight wear of a prosthetic device for the ocular surface. Design Retrospective interventional case series. Methods A clinical database of patients who underwent prosthetic replacement of the ocular surface ecosystem (PROSE) treatment from March 2003 to August 2008 was searched to identify patients treated for persistent corneal epithelial defect. In early 2003, overnight wear of a PROSE device and addition of commercially available, nonpreserved, topical ophthalmic moxifloxacin to the saline in the device reservoir became standard practice at this center when treating persistent corneal epithelial defect. Medical records were abstracted to obtain underlying diagnoses, previous treatments, days to re-epithelialization, and complications for subsequent analysis. Results PROSE treatment incorporating overnight wear, with adjunctive use of moxifloxacin, was employed in 20 eyes of 19 patients for a total of 372 days. Re-epithelialization occurred in 17 of 20 eyes. Median duration of treatment incorporating overnight wear was 8.5 days (range = 2-76 days). Healing occurred in ≤7 days in 12 eyes, 8-14 days in 3 eyes, and >14 days in 2 eyes (range = 1-35 days). There were no cases of microbial keratitis. Conclusions Overnight wear of a PROSE device is effective in promoting healing of persistent corneal epithelial defect. In comparison to an earlier series from this center, the rate of microbial keratitis as a complication of treatment has been reduced with the use of a nonpreserved topical fourth-generation fluoroquinolone in the device reservoir.