Debonding forces of different pads in a lingual bracket system

Area of Science:

• Orthodontics
• Biomaterials Science
• Dental Materials

Background:

• Lingual orthodontic brackets offer aesthetic advantages but require robust bonding solutions.
• Evaluating bracket design impacts bond strength and clinical success is essential.

Purpose of the Study:

• To compare the shear bond strength of lingual orthodontic brackets with metal pads versus resin pads.
• To analyze bond failure location and the adhesive remnant index (ARI) for both bracket types.

Main Methods:

• Forty extracted upper premolars were divided into two groups (n=20 each).
• One group received brackets with resin pads, the other with metal custom base pads.
• Shear bond strength was measured using an Instron universal testing machine; Student's t-test analyzed differences.

Main Results:

• A statistically significant difference in shear bond strength was observed between the groups (p < 0.001).
• Brackets with metal pads exhibited significantly higher shear bond strength than those with resin pads.

Conclusions:

• Lingual brackets with metal pads demonstrate superior bond strength compared to those with composite resin pads.
• The monolithic structure of metal pads contributes to their enhanced bond strength.
• Failure analysis indicated a higher incidence of resin pad failure between the bracket and the resin itself.