The purpose of study was to compare the bond strength of plasma xenon arc curing light with that of halogen light in orthodontic bracket bonding. One hundred extracted human premolars were prepared for bracket bonding. Group 1 was chemically cured and group 2 was cured by halogen light of Optilux 360(Demetron, U.S.A.) for 40seconds and group 3 was cured by plasma xenon arc light of Flippo(Lokki, France) for 3, 6, or 9 seconds. Each bonded bracket was tested on an Universal Testing Machine(Zwick Z020, Germany) to determine shear bond strength.
After bracket debonding, investigation of detached brackets and enamel surfaces using a´ ´scanning electron microscope(AKASHI Beam Technology SEM SX40 with WDX, Japan)was followed. Statistical analysis of the shear bond strengths and failure mode of brackets were made by means of the Scheffe test and chi-square test.
The results of this study were as follows, there were significant differences in shear bond strengths between the 3s plasma group and 6s plasma group and between the 9s plasma group and the other groups except the 6s plasma group(P<0.05), and there was no significant difference in failure mode between the groups (Chi-square, P>0.05).
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