Purpose: To analyze potential surface alterations in endosseous dental implants induced by irradiation with common dental lasers. Materials and Methods: Sandblasted and acid-etched, plasma-sprayed, hydroxyapatite-coated, and smooth titanium discs were irradiated using Nd:YAG, Ho:YAG, Er:YAG, CO2, and GaAlAs lasers at various power settings. The specimens were examined by scanning electron microscopy and energy dispersive spectroscopy. Results: In an energy-dependent manner, the pulsed YAG lasers induced partial melting, cracking, and crater formation on all 4 surfaces. Within the energy range applied, the CO2 laser caused surface alterations on the hydroxyapatite and plasma coatings as well as in the acid-etched surface. GaAlAs laser irradiation did not damage any of the surfaces. Energy dispersive spectroscopy revealed an altered chemical compound of the surfaces with regard to titanium, oxygen, and silicon. Discussion: The clinical application of most common dental laser systems can induce implant surface alterations. Relevant factors are not only the laser system and power setting, but also the application system. Conclusion: The results of the study indicate that Nd:YAG and Ho:YAG lasers are not suitable for use in decontamination of implant surfaces, irrespective of the power output. With the Er:YAG and CO2 laser, the power output must be limited so as to avoid surface damage. The GaAlAs laser seems to be safe as far as possible surface alterations are concerned. Keywords: energy dispersive spectroscopy, implant surface alteration, peri-implantitis, scanning electron microscopy