Implant-supported canine retraction using different reactivation intervals of elastomeric chains: A CBCT-based...

Area of Science:

• Orthodontics
• Dental Research
• Biomaterials

Background:

• Orthodontic treatment aims for efficiency in time, tooth positioning, and minimizing adverse effects.
• Activation frequency is an unexplored variable in optimizing orthodontic treatment efficiency.

Purpose of the Study:

• To evaluate the impact of different reactivation intervals on the efficiency of orthodontic tooth movement.
• To compare canine retraction rates, tipping, rotation, root resorption, and pain across varying activation frequencies.

Main Methods:

• A split-mouth randomized controlled trial involved 38 patients with specific malocclusions requiring premolar extraction and canine retraction.
• Elastomeric chains (150g) were replaced at 2, 4, 6, or 8-week intervals in 36-37 quadrants per group.
• Canine retraction rate was the primary outcome; tipping, rotation, root resorption, and pain were secondary outcomes, with blinded outcome assessors.

Main Results:

• Canine retraction rates were similar across all intervals (2, 4, 6, 8 weeks).
• Significantly higher root resorption occurred with shorter intervals (2 and 4 weeks) compared to longer intervals (6 and 8 weeks).
• No significant differences in canine tipping, rotation, or reported pain were observed between groups.

Conclusions:

• Reactivation intervals of 2, 4, 6, and 8 weeks yield comparable rates of canine retraction, tipping, rotation, and pain.
• Longer reactivation intervals (6-8 weeks) are associated with reduced root resorption, suggesting a more favorable outcome for root health.
• The study highlights the importance of activation frequency in minimizing adverse effects like root resorption during orthodontic treatment.