Comparison of the shear bond strength of brackets using the led curing light and plasma arc curing light: polymerization time.

The xenon plasma arc curing light and the LED curing light have substantially decreased the time required for polymerizing a bracket bonding composite. However, the expense and size of the plasma arc curing light has limited its use. The LED curing light is less expensive, smaller in size, and easier to handle. This study compared the bond strength afforded by the plasma arc curing light with that produced by the LED curing light, according to the polymerization time. In addition, the polymerization time required for adequate adhesion of the bracket was examined. After positioning the orthodontic brackets with the composite resin onto 120 human premolars, the plasma arc curing light and the LED curing light were used to polymerize the composite resin at 4-, 6-, and 8-second timepoints. The results showed that the LED curing light produces a bond strength sufficient for maintaining the orthodontic bracket even with a short burst of polymerization. Therefore, it is expected that the LED curing light will be readily accepted by orthodontists.