Carbon dioxide (CO2) laser surgery is advantageous in current clinical situations. The controlled and precise destruction of target tissue has made it a recommended procedure in intraoral surgery. Implant surgery demands minimal thermal changes in bone surrounding the implant. In this experimental study, different types of implants were placed in vitro in the mandible of a pig and in vivo in the mandibles of two dogs. In continuous mode, 4 and 6 watts, and in repeated pulse, 5 and 8 watts, for 2, 4, and 5 seconds, the CO2 laser contacted several places around and on the implants. Temperature changes were measured at the implant-bone junction. The results showed that the CO22 laser produced minimal temperature changes in the continuous mode power setting at less than 4 watts and in the repeated pulse, 0.05 second-interval power setting at less than 8 watts. Schlagwörter: CO2 laser, endosseous implant, thermal changes