Table 1. Descriptive statistics including mean shear bond strength (MPa) and SD of study groups .

Group	Number	Mean	SD	P value
AM	20	30.45	1.63	< 0.001
AC	20	32.25	1.37
LC	20	20.12	3.43
LM	20	18.32	3.00
AM (acid etching/ metal brackets), AC (acid etching/ ceramic brackets), LM (laser etching/ metal brackets) and LC (laser etching/ ceramic brackets).