Many studies have been done on the shear bond strength of brackets adhered to acid-etched enamel and so far, there is no study on shear bond strength of brackets adhere to laser-etched enamel in Iraq. So, this study is an attempt to compare the shear bond strength of brackets adhered to laser-etched enamel with that of brackets adhered to acid-etched enamel. The application of laser irradiation to etch dental enamel for direct bonding of orthodontic appliance has been studied. CO2 (Carbon Dioxide) laser are capable of producing surface irregularities in human enamel which resemble those resulting from etching of enamel with ortho-phosphoric acid. Whether laser conditioning improves the retention of composite resins to the same degree as conventional acid-etching techniques has been the subject of several investigations. Это и многое другое вы найдете в книге Shear Bond Strength of Brackets Adhered to laser-Etch Versus Acid-Etch