Effect of surface treatment with sandblasting and Er,Cr:YSGG laser on bonding of stainless steel orthodontic brackets to silver amalgam

Abstract

Objectives: Satisfactory bonding of orthodontic attachments to amalgam is a challenge for orthodontists. The aim of this in vitro study was to compare the shear bond strength of stainless steel orthodontic brackets to silver amalgam treated with sandblasting and Er,Cr:YSGG laser. Study Design: Fifty-four amalgam discs were prepared, polished and divided into three groups: In group 1 (the control group) the premolar brackets were bonded using Panavia F resin cement without any surface treatment; in groups 2 and 3, the specimens were subjected to sandblasting and Er,Cr:YSGG laser respectively, before bracket bonding. After immersing in distilled water at 37°C for 24 hours, all the specimens were tested for shear bond strength. Bond failure sites were evaluated under a stereomicroscope. Data was analyzed using one-way ANOVA and a post hoc Tukey test. Results: The highest and lowest shear bond strength values were recorded in the laser and control groups, respectively. There were significant differences in mean shear bond strength values between the laser and the other two groups (p<0.05). However, there were no significant differences between the sandblast and control groups (p=0.5). Conclusions: Amalgam surface treatment with Er,Cr:YSGG laser increased shear bond strength of stainless steel orthodontic brackets. Key words: Amalgam, surface treatment, shear bond strength, sandblasting, Er,Cr:YSGG laser.

The effect of surface treatment with Er:YAG laser on shear bond strength of orthodontic brackets to fiber-reinforced composite

“…Previous authors indicated the capability of Er:YAG laser in roughening different surfaces such as composite ( 15 - 16 ), amalgam ( 23 ) and bracket bases ( 17 - 18 ). Although microscopic evaluaion of the FRC surfaces was not performed in this study, it is possible that laser conditionng provides microporosities and microretentive areas on the FRC surface which increase the surface area for bonding, thus leading to enhanced bond strength of ortodontic attachments.…”

An in vitro evaluation of the effect of sandblasting and laser surface treatment on the shear bond strength of a composite resin to the facial surface of primary anterior stainless steel crowns

“…Roughening the metal surface improves the adhesive interfacial bond strength; this is primarily due to the increased surface area available for bonding and also due to mechanical interlocking feature. Similar mechanical retention represents the predominant mechanism in bracket bonding technique through a mesh base ( 9 , 18 ). It is important to be able to produce the roughened surface repeatedly and uniformly in order to ensure a high degree of reproducibility the process parameters must be tightly controlled which is possible using a laser ( 18 ).…”

A Comparison of Shear Bond Strengths of Metal and Ceramic Brackets using Conventional Acid Etching Technique and Er:YAG Laser Etching

“…Lasers have been used in orthodontics for conditioning of enamel and nonenamel tooth surfaces, 3 - 6 composite removal from bracket base for recycling of brackets, 7 - 9 debonding of ceramic brackets, 10 - 12 and curing. 13 Laser irradiation causes thermal changes on the enamel surface and produces irregular porosities similar to acid etching, 14 which are 10-20 µm in depth and can be used for conditioning of enamel and bonding procedures.…”