Optimization of a procedure for rebonding dislodged orthodontic brackets

• Published in: The Angle orthodontist Vol. 69; no. 3; pp. 276 - 281
• Main Authors: Mui, B, Rossouw, P E, Kulkarni, G V
• Format: Journal Article
• Language: English
• Published: United States 01.06.1999
• Subjects: Acid Etching, Dental - methods; Bisphenol A-Glycidyl Methacrylate - chemistry; Composite Resins - chemistry; Dental Bonding - instrumentation; Dental Bonding - methods; Dental Enamel - ultrastructure; Dental Prophylaxis - instrumentation; Dentistry; Equipment Failure; Humans; Orthodontic Brackets; Phosphoric Acids - administration & dosage; Stress, Mechanical; Surface Properties; Tungsten Compounds
• ISSN: 0003-3219

The purpose of this study was to compare shear bond strength (SBS) of bonded and rebonded orthodontic brackets following a variety of commonly used conditioning treatments and using both light-cured and self-cured composite resin systems. Brackets debonded during the initial determination of SBS were rebonded after the removal of residual resin from enamel surfaces using five different treatments: (1) Remove residual resin using a tungsten carbide bur, re-etch enamel surface, then bond a new bracket; (2) Remove resin from the base mesh with micro-etching then rebond the same bracket, (3) Remove residual resin from the enamel surface using resin-removing pliers, recondition the enamel with an air-powder polisher, then bond a new bracket; (4) Remove residual resin using a rubber cup and pumice, then bond a new bracket; (5) Remove residual resin using pliers alone, then bond a new bracket. The results revealed that the light-cured system produced higher shear bond strength in the initial bond than the self-cured system (p<0.005). Reconditioning the enamel surfaces using a tungsten carbide bur and acid-etching gave the highest SBS (difference 5.8 MPa; p<0.01) and clinically favorable fracture characteristics. The data suggest that the optimal procedure for rebonding dislodged orthodontic brackets is to resurface the enamel using a tungsten carbide bur, acid-etch the enamel, and use a new or re-use an old bracket after microetching.