Is laser conditioning a valid alternative to conventional etching for aesthetic brackets?

Area of Science:

• Orthodontics
• Biomaterials Science
• Laser Dentistry

Background:

• Conventional acid-etching is standard for enamel conditioning before bracket bonding.
• ER:Yag lasers offer a potentially conservative alternative for enamel conditioning.
• Aesthetic orthodontic brackets are increasingly used in clinical practice.

Purpose of the Study:

• To evaluate the efficacy of ER:Yag laser enamel conditioning for bonding various aesthetic orthodontic brackets.
• To compare shear bond strength (SBS) and Adhesive Remnant Index (ARI) scores between laser and acid-etching techniques.

Main Methods:

• Five types of aesthetic brackets (microfilled copolymer, glass fiber, sapphire, polyoxymethylene, sintered ceramic) were tested.
• Two hundred bovine incisors were conditioned using either acid-etching or ER:Yag laser.
• Brackets were bonded, and shear bond strength was measured using a Universal Testing Machine.

Main Results:

• Acid-etching yielded higher SBS for sapphire, polyoxymethylene, and sintered ceramic brackets.
• ER:Yag laser conditioning significantly decreased SBS for sapphire, polyoxymethylene, and sintered ceramic brackets.
• No significant SBS reduction was observed for microfilled copolymer and glass fiber brackets with laser conditioning.

Conclusions:

• ER:Yag laser conditioning can compromise the bond strength of certain aesthetic orthodontic brackets, particularly sapphire, polyoxymethylene, and sintered ceramic types.
• Laser conditioning may be a viable alternative for microfilled copolymer and glass fiber brackets due to maintained bond strength.
• Further research is needed to optimize laser parameters for effective bonding of all aesthetic bracket types.