Purpose: The aim of this study was to evaluate the 5-year success rate of zirconia (ZrO2) implants with three different kinds of surfaces. Materials and Methods: One-piece zirconia dental implants (CeraRoot) with three different roughened surfaces were designed and manufactured for this study: coated, uncoated, and acid-etched. Five different implant designs were manufactured. Standard or flapless surgical procedures were used for implant placement. Simultaneous bone augmentation or sinus elevation was performed when bone height or width was insufficient. Definitive all-ceramic restorations were placed 4 months after implant placement (8 months or more for implants when bone augmentation or sinus elevation was performed). The implants were followed up to 5 years (mean, 3.40 +/- 0.21). Results: In all, 831 implants were placed in 378 patients with a mean age of 48 years. The overall implant success rate after 5 years of follow-up was 95% (92.77% for uncoated implants, 93.57% for coated implants, and 97.60% for acid-etched implants). The success rate of the acid-etched surface group was significantly better than that of the other two. Conclusion: From this midterm investigation, it can be concluded that zirconia dental implants with roughened surfaces might be a viable alternative for tooth replacement. Further follow-up is needed to evaluate the long-term success rates of the implant surfaces studied. Int J Oral Maxillofac Implants 2010;25:336-344.