Effects on the shear bond strength of orthodontic brackets with different concentration of fluorided etching fluid
Ma, J.; Zhang, Y.; Hong, Y.-h.
Hua Xi Kou Qiang Yi Xue Za Zhi 23(5): 397-399
2005
ISSN/ISBN: 1000-1182 PMID: 16285544 Document Number: 592386
This study was to find out the most suitable concentration of added NaF to enough bonding strength of brackets. Sixty-four teeth were randomly divided into A, B, C and the control group. NaF of four different concentrations (1.23%, 2%, 3% and 0%) was added into 35% phosphoric acid. The four group teeth were etched with four kinds of fluoride etching fluid respectively and were bonded with brackets. Four specimens in each group were selected by turns after 1, 4, 12 and 24 weeks of bonding. The shear bond strength of the teeth were tested, and the adhesive residual index (ARI) of bonding interface were recorded. The shear bond strength at four test time in each group was no significant (P > 0.05). There was statistical difference of the shear bond strength between four groups (P < 0.05), and group C was lower than the other groups. The ARI was no statistical difference between four groups. The effects of etching and bonding had no significant changes when the concentration of added NaF was no more than 2%. The shear bond strength decreased while the concentration of NaF was higher than 3%.