|
Adhesive Remnants in Orthodontic Brackets: A Microscopic Study
S Vikram1, Shiji M Kunjappan2, P Vasanthan3, S Sabitha4, Ajeetha Gomathi Selvarajan5, V Saranya6
1 Professor and Head of the Department, Department of Orthodontics & Dentofacial Orthopedics, Vinayaka Mission's Sankarachariyar Dental College, Salem, Tamil Nadu, India
2 Reader, Department of Orthodontics, Vinayaka Mission's Sankarachariyar Dental College, Salem, Tamil Nadu, India
3 Professor, Department of Orthodontics, Vinayaka Mission's Sankarachariyar Dental College, Salem, Tamil Nadu India
4 Reader, Department of Oral and maxillofacial surgery, Vinayaka Mission's Sankarachariyar Dental College, Salem, Tamil Nadu, India
5 Former Professor and Head of the Department, Department of Orthodontics, Vivekanandha Dental College for Women, Elayampalayam, Tiruchengode, Namakkal, Tamil Nadu, India
6 Post-graduate Student, Department of Oral and Maxillofacial Pathology, Ragas Dental College, Chennai, Tamil Nadu, India
Correspondence Address:
 Source of Support: None, Conflict of Interest: None  | Check |
|
|
Background: The concept of bonding resins to enamel has enjoyed applications in all fields of dentistry, including the bonding of orthodontic brackets. In the process of bonding orthodontic brackets to enamel, conventional adhesive systems use three different agents: An enamel conditioner, a primer solution, and an adhesive resin. The bonded brackets should have enough bond strength to withstand masticatory forces, the forces applied during orthodontic treatment and should enable easy debonding, clean up procedure at the end of the treatment without causing iatrogenic damage such as cracks and loss of enamel. Depending on the mode and direction of the loading force different types of bond strengths are evident. Thus, the aim of the study is to evaluate the adhesive remnant index (ARI) of Metal-Chrome Cobalt TP Nu-edge L N bracket system with Primekote base and to compare it with that of 3M Gemini Metal-Stainless Steel bracket with woven mesh base and Ormco Metal-Stainless Steel bracket with the Optimesh base.
Materials and Methods: Three commercially available pre-adjusted edgewise premolar brackets with different base designs were used for the study on 54 premolar teeth. An optical microscope was used to determine the enamel crack after debonding. Scoring was done to calculate the ARI. Statistical analysis: Chi-square test was performed.
Results: Varying fracture sites were noted for 3M Gemini and TP Primekote brackets, with 44% of bond failure occurring at the bracket/adhesive interface. Ormco Optimesh brackets had bond failure site at bracket adhesive interface in about 66% of the samples. The difference in ARI scores noted was statistically significant. The bond failure for tensile bond strength test group occurred at the bracket/adhesive interface.
Conclusion: Sites of bond failure after tensile bond strength test was mostly at the bracket/adhesive interface or within the adhesive. None of the brackets showed failure at the enamel/adhesive interface. Hence, tensile stress can be used for debonding. |
