Comparative Evaluation of Shear Bond Strength of Orthodontic Brackets Bonded After Recycling by Using Four Different Methods: An in-Vitro Study
*Address for Correspondence: DR. Shirish M. Bapat, B.D.S., M.D.S. Director Principal & HOD, K.D. Dental College & Hospital NH-2, P.O. Chhatikara Mathura-281006, U.P. E-mail: email@example.com
Frequent debonding of brackets is a commonest problem in orthodontic treatment which prolongs the treatment. It becomes expensive for the orthodontist to rebond new bracket for every bond failure. Therefore, rebonding same bracket is preferred if the bond strength is adequate.
The purpose of present study was to determine a simple, effective method for reconditioning debonded stainless steel orthodontic brackets for rebonding in the orthodontic office.
Materials and Methods
Total 120 new brackets (control group) were bonded to freshly extracted premolar teeth, then debonded and the bond strength recorded. The debonded brackets were then divided into four groups which were reconditioned using different techniques: (1) Green stone bur (Group A), (2) Flaming followed by acid bath (Group B), (3) Flaming followed by electro polishing (Group C), (4) Sandblasting (Group D). The brackets were rebonded to the premolar teeth, and their bond strengths were measured.
The mean shear bond strength of green stone bur, flaming followed by acid bath and flaming followed by electro polishing methods were found to be 9.99 MPa, 8.2 MPa, and 8.3 MPa, respectively and were statistically significant when compared with the control group (12.62MPa). However, sandblasting method had highest mean shear bond strength of 10.9 MPa which was not significant compared to that of the control group.
Sandblasting method can be recommended for recycling brackets in orthodontic practice as it was comparable to using new brackets for bonding. However, other methods which also gave sufficient bond strength are more simple and economical.
green stone bur, acid bath, electro polishing, sandblasting.