One-arch Orthodontic Bonding Using a Bleaching Light Curing Unit

Objectives: To investigate the bond strengths achieved when using a Bleaching Curing Light (BCL) to cure orthodontic bracket light cure bonding cement.
Methods: 160 anterior bovine teeth were used to form 20 average sized human arches (8 teeth in each). These were divided into 2 groups according to the light curing method used: group 1 (Bleaching Curing Light for 40 seconds) and the group 2 (conventional light cure for 10 seconds). After a 24-hour latency period in a controlled humid environment, Shear Bond Strength (SBS) and Adhesive Remnant Index (ARI) were calculated.
Results: Statistically significant differences were found according to bracket position along the arch. Group 1 showed significantly lower SBS in the most posterior position, which corresponds to the mean position of first molar attachments (group 1: 2.86±1.68MPa, group 2: 3.38±1.36MPa), and significantly higher bond strength in the most anterior position (group 1: 5.07±1.85MPa, group 2: 3.80±1.16MPa). A high correlation was found between the position of the bracket and the debonding values (p<0.02). Bonding failures occurred more frequently in the more posterior arch positions within group 1. No significant correlations were found between ARI and the debonding force within both groups. Group 2 showed significantly lower ARI than group 1.
Conclusions: Light curing orthodontic bracket cement with the BCL was found to result in clinically relevant bond strength values in the anterior and premolar regions. Therefore, this procedure may be acceptable in the incisor and premolar area, while curing of the posterior segments should be done separately.