الفهرس | Only 14 pages are availabe for public view |
Abstract one proplem that clinicians face during treatment is the bracket failure. This is usually the consequence of a patient accidently applying inappropriate force to the bracket or a poor bonding technique. Thus, a significant number of teeth must be rebonded in a busy orthodontic practice. One solution is to recycle the brackets. Bracket recycling can be performed either in the dental office or by specialized companies. However, because of time consuming process of commercial recycling, in-office recycling is preferred option. The in-office recycling method employed in this study was the Er:YAG laser. The purpose of the present study was to evaluate the effects of recycling and repeated recycling with Er:YAG laser on shear bond strength and surface characteristics of stainless steel orthodontic brackets. This study was carried on ninety human upper first premolars extracted as a part of orthodontic treatment. The teeth were randomly divided into 3 groups; one control and two experimental groups of 30/ each. group I (control group): Thirty new brackets were bonded to upper first premolars and subdivided into: •Twenty brackets for shear bond strength testing. •Ten brackets debonded for scanning electron microscope to identify the surface characteristics of the bracket mesh. group II: Thirty debonded brackets were recycled one time with Er:YAG laser and subdivided into: •Twenty recycled brackets were rebonded to upper first premolars as with initial bonding and subjected to shear bond strength testing. |