COMPARISON OF SURFACE-TREATED AND UNTREATED ORTHODONTIC BANDS - EVALUATION OF SHEAR FORCE AND SURFACE-ROUGHNESS

In an attempt to increase retention of orthodontic bands, orthodontic companies market bands with surfaces prepared to increase roughness. A comparison of six groups of bands, including two with untreated surfa ces, revealed a wide range of variation in shear forces. Three classes of retention may be differentiated on the basis of non-statistically significantly different mean shear forces in each category: high (Unit ek, treated), moderate (Unitek, untreated; A Co., treated; GAG, treate d), and low (A Co., untreated; Dentaurum, treated). Surface roughness, as evaluated through atomic force microscopy, correlated moderately w ith shear force (r = 0.61; p < 0.05). This method is examined and comp ared with the qualitative profiles of the orthodontic band surfaces pr ovided by optical micrography.