Effects of diode and Nd : YAG laser irradiation on titanium discs: A scanning electron microscope examination

Background: Dental lasers have been recommended for uncovering submerged im plants as well as decontaminating implant surfaces when treating peri-impla ntitis. The aim of this study was to show the possible alterations in titan ium disc surfaces using an Nd:YAG or a diode laser, Methods: Three different titanium discs were used (sandblasted, titanium pl asma-sprayed [TPS], and hydroxyapatite [HA] coated) to determine the effect s of laser irradiation on these surfaces using a scanning electron microsco pe (SEM). The discs were either irradiated with a pulsed Nd:YAG laser with a contact handpiece and power settings of 2.0, 4.0, and 6.0W or with a diod e laser at 5.0, 10.0, and 15.0W power settings and continuous wave (cw) in the contact handpiece. Irradiated areas were compared with control titanium sites which were not lased. The specimens were prepared for SEM examinatio n after the disc irradiation. Results: The SEM examination demonstrated extensive melting in all of the N d:YAG laser irradiated areas. Damage was seen in all TPS- and HA-coated dis cs even at the lowest power setting. toss of porosity, coating microfractur es, and a relatively smooth surface were observed. In contrast, the diode l aser did not cause any damage or modify the disc surface. Regardless of the power setting, there was no visible difference between lased and non-lased surfaces after cw irradiation with the diode laser. Conclusions: From these findings, it was concluded that the diode laser (98 0 nm) does not damage titanium surfaces, which should be of value when unco vering submerged implants and treating peri-implantitis.