Recycling stainless steel orthodontic brackets with Er:YAG laser - An environmental scanning electron microscope and shear bond strength study

ABSTRACT Objectives: To evaluate the in vivo effects of two acidic soft drinks (Coca-Cola and Sprite) on the shear bond strength of metal orthodontic brackets with and without resin infiltration treatment. In addition, the enamel surface was evaluated, after debonding, using a scanning electron microscope. Materials and Methods: Sixty noncarious maxillary premolars, scheduled for extraction in 30 orthodontic patients, were used. Patients were randomly divided into two groups according to the soft drink tested (Coca-Cola or Sprite). In each group, application of resin infiltration (Icon. DMG, Hamburg, Germany) was done on one side only before bonding of brackets. Patients were told to rinse their mouth with their respective soft drink at room temperature for 5minutes, three times a day for 3months. Shear bond strength was tested with a universal testing machine. After shearing test, a scanning electron microscope was used to evaluate enamel erosion. Statistical analysis was performed by twoway analysis of variance followed by the least significant difference test. Results: The Coca-Cola group without resin infiltration showed the lowest resistance to shearing forces. Scanning electron micrographs of both groups after resin application showed a significant improvement compared with results without resin use, as the enamel appeared smoother and less erosive. Conclusion: Pretreatment with the infiltrating resin has proved to result in a significant improvement in shear bond strength, regardless of the type of soft drink consumed.

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A comparative evaluation of the effectiveness of erbium-doped yttrium aluminum garnet laser with other in house refurbishing methods for reconditioning stainless steel and ceramic brackets. An environmental scanning electron microscope and shear bond strength analysis: An in-vitro study

APOS Trends in Orthodontics ◽

10.4103/2321-1407.163422 ◽

2015 ◽

Vol 5 ◽

pp. 202-207

Author(s):

Nimay Devjee ◽

Sonali V. Deshmukh ◽

Sandeep Jethe ◽

Charudatta R. Naik

Keyword(s):

Stainless Steel ◽

Bond Strength ◽

Shear Bond Strength ◽

Yttrium Aluminum Garnet ◽

Er:Yag Laser ◽

Environmental Scanning ◽

Erbium Doped ◽

Yttrium Aluminum ◽

Ceramic Brackets ◽

Scanning Electron

Introduction Brackets can be recycled by sending them to a commercial recycling company but it is time consuming and the bracket cannot be bonded in the same appointment. Hence in-house methods for recycling of brackets would be beneficial to both the orthodontist and the patient. Aim In our study, we compared the shear bond strength of brackets after being recycled with erbium-doped yttrium aluminum garnet (ER:YAG) laser, sandblasting and the thermal method. Materials and Methods The study was carried out on 126 extracted premolars. The bonding procedure was performed with mandibular premolar metal and premolar ceramic brackets. Eighty-four teeth were subdivided into three groups for each method of recycling. These groups were further subdivided into two groups of 14 teeth each for the types of brackets used. Prior to the initial bonding the bracket was also viewed under an environmental scanning electron microscope to examine the meshwork of the brackets and once again after the respective recycling methods had been performed. Results We found that for stainless steel brackets, the sandblasting method was superior to the ER:YAG laser, as the recycled brackets showed a higher shear bond strength. For ceramic brackets the ER:YAG laser recycled group had the highest recycled shear bond strength therefore was the best method of recycling ceramic brackets.

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