In vitro peel/shear bond strength evaluation of orthodontic bracket base design

Area of Science:

• Orthodontics
• Biomaterials Science
• Dental Materials

Background:

• Bracket-enamel adhesion is crucial for successful orthodontic treatment.
• Understanding the adhesive capacity of various bracket types is essential for clinical decision-making.
• Recycled metal brackets present a potential cost-effective option, but their bonding performance requires thorough evaluation.

Purpose of the Study:

• To compare the adhesive capacity of 17 different orthodontic bracket types.
• To evaluate the effect of aluminum oxide air abrasion on recycled metal bracket bonding.
• To determine the influence of bracket base design on bond strength.

Main Methods:

• In vitro peel/shear testing was conducted on 17 bracket types.
• Orthodontic adhesive Concise was used for all bonding procedures on silane-treated metal substrates.
• Scanning electron microscopy (SEM) was employed for morphological examination of bracket bases.

Main Results:

• Adhesive capacity varied significantly, with ceramic brackets (Allure Accu Arch) showing the highest bond strength (13.9 MPa) and plastic brackets (CeramaFlex Advant Edge) the lowest (1.6 MPa).
• Certain metal brackets (Mini Masters, Omni Arch) demonstrated comparable bond strength to high-performing ceramic brackets.
• Bracket wing fracture was noted in some ceramic brackets, and air abrasion of recycled metal brackets yielded inconsistent results.

Conclusions:

• The bracket base material and design are primary determinants of adhesive capacity.
• While ceramic brackets can offer superior bond strength, metal brackets may provide a viable alternative.
• The effectiveness of sandblasting recycled metal bracket bases for improved adhesion is not uniform.