Method: The tests wereperformed in dry enviroment and moistured by artificial saliva (OralBalance), using an EMIC DL 10000 testing machine, simulating asliding of 2 mm of a 019" x 025" rectangular stainless steel wiresover the preangulatedand pretorqueated(right superior canine,roth prescription, slot 0.022"X0.030") brackets (n=18 for eachbracket). For comparisons between groups, in dry and moisturedenviroment, the ANOVA was used and for comparisons related tothe dry x moistured enviroment, the student t test was used foreach group.
Result: The results showed that, in the absence ofsaliva , the Radiance® monocrystalline brackets showed thehighest friction coefficients, followed by the 20/40® and the InVu®polycrystalline brackets. In tests with the artificial saliva, theRadiance® and the 20/40® brackets had statistically similarfriction coefficients and both were greater than that presented bythe InVu® brackets. The artificial saliva did not change themaximum friction force of the Radiance® brackets, but, for theothers (20/40® and InVu®), an increase of friction was observed inits presence.
Conclusion: The InVu® brackets showed, in theabsence and in the presence of saliva, the lowest frictioncoefficient among the brackets tested.