Stress distribution during orthodontic maxillary canine retraction using 3D finite element analysis

Area of Science:

• Orthodontics
• Biomaterials Engineering
• Computational Mechanics

Background:

• Maxillary canine retraction is a critical orthodontic procedure.
• Understanding stress distribution in the periodontium is essential for optimizing treatment and preventing root resorption.
• Current methods for analyzing biomechanical forces during retraction have limitations.

Purpose of the Study:

• To analyze and compare stress distribution in the periodontium during maxillary canine retraction.
• To evaluate the biomechanical effects of applying forces at the canine orthodontic bracket versus a power arm.

Main Methods:

• A three-dimensional finite element analysis (3D FEA) model was developed using ANSYS software.
• The model included the power arm, archwire, orthodontic bracket, and periodontium.
• Simulations were performed with varying force applications (150 gm) at different points.

Main Results:

• Maximum stress in the periodontium was observed when a 150 gm force was applied at a power arm soldered to the canine bracket at 13 mm.
• Minimum stress in the periodontium occurred with force application directly at the canine bracket hook.
• Maximum principal stress (tension) and minimum principal stress (compression) were highest at the power arm (9mm) and lowest at the canine bracket hook.

Conclusions:

• The location of force application significantly influences stress distribution in the periodontium during maxillary canine retraction.
• Using a power arm, especially at greater distances from the bracket, generates higher stress concentrations.
• Force application directly at the canine bracket hook appears to distribute stress more favorably within the periodontium.