Reliable coupling of orthodontic elements to mini-implants: An in-vitro study

Area of Science:

• Orthodontics
• Biomaterials Engineering
• Dental Implantology

Background:

• Mini-implants are crucial in orthodontics for anchorage.
• Reliable fixation of wires to mini-implants is essential for effective treatment.
• Current methods for wire fixation require evaluation for mechanical strength and durability.

Purpose of the Study:

• To compare the reliability of mechanical and adhesive fixation methods for rectangular wires in mini-implants.
• To assess the influence of different surface preparation techniques on adhesive fixation strength.
• To evaluate the durability of fixation methods under simulated intraoral conditions.

Main Methods:

• Rectangular wires were fixed to mini-implants using either mechanical crimping or four adhesive preparation methods.
• Adhesive preparation involved untreated wire, ROCATEC-Pre, ROCATEC-PRE + Espe Sil, and ROCATEC-PRE + ROCATEC-PLUS + Espe Sil.
• Fixation integrity was tested using a universal testing machine after aging via 500 temperature cycles.

Main Results:

• The untreated wire with adhesive showed the lowest maximum load capacity (3 N and 10.8 N) and failed quickly during aging.
• The most effective adhesive fixation (Adh. 4: sandblasted and silanized) withstood the highest loads (average 43.3 N, 41.5 N after aging).
• Mechanical fixation with a crimped ligature demonstrated reliable strength, withstanding an average load of 38.7 N.

Conclusions:

• Adhesive fixation is most effective for rectangular wires in mini-implants when the wire is sandblasted and silanized prior to application.
• Mechanical coupling using a crimped ligature provides a reliable alternative for wire fixation in mini-implant systems.