ABSTRACT

The aim of the study was to test the shear bond strength and surface characteristics when applying laser beam at different angulations with different power outputs to the enamel surface In the research 90 extracted human premolar teeth were used. Teeth were etched with Erbium, Chromium: Yttrium, Scandium, Gallium, Garnett (Er, Cr: YSGG) laser at three different power outputs (1,1.25 and 1.5 Watt, 140 nm, 20 Hz) and two different beam an-gulations(45 and 90°). There was no statistically significant difference between the groups in shear bond strengths and adhesive remnant indexes. Laser beam angulation, at these power outputs, does not make sense. All of the other power outputs, except 1 Watt at 900 produced similar etching patterns at both laser beam angulations. It is not extremely important to use the handpiece of the Er, Cr: YSGG laser at different angles to the enamel to etch for orthodontic purposes.