J Oral Maxillofac Surg 70:1064-1069, 2012 Comparative Evaluation of Antimicrobial Effects of Er:YAG, Diode, and CO 2 Lasers on Titanium Discs: An Experimental Study Emre Tosun, DDS, PhD,* Ferda Tasar, DDS, PhD,† Robert Strauss, DDS, MD,‡ Dolunay Gulmez Kıvanc, MD,§ and Cem Ungor, DDS, PhD Purpose: This study examined carbon dioxide (CO 2 ; 10,600 nm), diode (808 nm), and erbium (Er):yttrium-aluminum-garnet (YAG; 2,940 nm) laser applications on Staphylococcus aureus contami- nated, sandblasted, large-grit, acid-etched surface titanium discs and performed a comparative evaluation of the obtained bactericidal effects and the applicability of these effects in clinical practice. Materials and Methods: This study was carried out in 5 main groups: Er:YAG laser in very short pulse (VSP) emission mode, Er:YAG laser in short pulse (SP) emission mode, diode laser with a 320-nm fiber optic diode laser with an R24-B handpiece, and CO 2 laser. After laser irradiation, dilutions were spread on sheep blood agar plates and, after an incubation period of 24 hours, colony-forming units were counted and compared with the control group, and the bactericidal activity was assessed in relation to the colony counts. Results: The CO 2 laser eliminated 100% of the bacteria at 6 W, 20 Hz, and a 10-ms exposure time/pulse with a 10-second application period (0.8-mm spot size). The continuous-wave diode laser eliminated 97% of the bacteria at 1 W using a 10-second application with a 320-m optic fiber, 100% of the bacteria were killed with a 1-W, 10-second continuous-wave application with an R14-B handpiece. The Er:YAG laser eliminated 100% of the bacteria at 90 mJ and 10 Hz using a 10-second application in a superpulse mode (300-ms exposure time/pulse). The Er:YAG laser also eliminated 99% to 100% of the bacteria in VSP mode at 90 mJ and 10 Hz with a 10-second application. Conclusions: The results of this study show that a complete, or near complete, elimination of surface bacteria on titanium surfaces can be accomplished in vitro using a CO 2 , diode, or Er:YAG laser as long as appropriate parameters are used. © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved. J Oral Maxillofac Surg 70:1064-1069, 2012 Over the past 20 years, dental implants have become a successful treatment option for the replacement of miss- ing teeth of edentulous or partially edentulous patients. The failure and loss of implants currently is a major problem in dental implantology. Implant-related prob- lems generally are attributed to bacterial infection, sur- gical trauma, occlusal overload, misplaced implants, and incorrect prosthetic design. 1,2 Peri-implantitis is an inflammatory process charac- terized by progressive bone loss around osseointe- grated implants. Several treatment options such as guided bone regeneration, 3-5 implant decontamina- Received from the Faculty of Dentistry Department, of Oral and Maxillofacial Surgery, Blacksea Technical University, Trabzon, Tur- key. *Faculty of Dentistry, Department of Oral and Maxillofacial Sur- gery, Blacksea Technical University, Trabzon, Turkey. †Faculty of Dentistry, Department of Oral and Maxillofacial Sur- gery, Hacettepe University, Ankara, Turkey. ‡Faculty of Dentistry, Department of Oral and Maxillofacial Sur- gery, Virginia Commonwealth University, Richmond, VA, USA. §Faculty of Medicine, Department of Microbiology, Hacettepe University, Ankara, Turkey. Faculty of Dentistry, Department of Oral and Maxillofacial Sur- gery, Blacksea Technical University, Trabzon, Turkey. Address correspondence and reprint requests to Dr Tosun: Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Blacksea Technical University, Trabzon, Turkey; e-mail: emretosun1980@ gmail.com © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved. 0278-2391/12/7005-0$36.00/0 doi:10.1016/j.joms.2011.11.021 1064