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Evaluation of force systems generated by Memory Titanol® springs with different preactivation bends
Henrique Barcelos Brandão1, Jonas Bianchi1, Lucas Arrais de Campos1
1São Paulo State University, School of Dentistry, Department of Morphology and Child Clinic - Orthodontics (Araraquara/SP, Brazil).
Dental Press Journal of Orthodontics
|October 9, 2024
Summary
Different preactivation bends in Memory Titanol® springs (MTS) generated varying forces. Group 3 (60º) produced intrusive molar forces, while Groups 1 and 2 (0º and 45º) resulted in extrusive forces and intrusive premolar forces.
Area of Science:
- Orthodontics and Dental Biomaterials
- Biomechanical Engineering in Dentistry
- Materials Science in Orthodontic Appliances
Background:
- The Memory Titanol® spring (MTS) is a nickel-titanium (NiTi) based orthodontic appliance.
- Understanding the force system generated by MTS with varying preactivation is crucial for predictable tooth movement.
- Previous studies have not fully elucidated the biomechanical effects of specific preactivation angles on MTS.
Purpose of the Study:
- To evaluate the biomechanical force system generated by the Memory Titanol® spring (MTS) with different preactivation angles.
- To quantify the vertical forces and moments on molars and premolars under varying MTS activations.
- To provide data for optimizing orthodontic treatment planning using MTS.
Main Methods:
- Three preactivation angles (0º, 45º, 60º) were tested on MTS using an orthodontic force tester (OFT).
- Activations were applied to a 0.018 × 0.025-in NiTi segment with a 30º posterior activation (β).
- Forces and moments on molar and premolar segments were measured and analyzed for each group (G1, G2, G3).
Main Results:
- Molar vertical forces ranged from -1.33 N (extrusion) in G1 to 0.33 N (intrusion) in G3.
- Premolar forces were intrusive in G1 (-1.34 N) and G2 (-0.77 N), and extrusive in G3 (0.31 N).
- Molar upright moments were distal in G1 (53.45 N.mm) and G2 (19.87 N.mm), and mesial in G3 (-6.23 N.mm).
Conclusions:
- Preactivation angles significantly influence the force system of MTS.
- A 60º preactivation (G3) results in intrusive molar forces and distal premolar moments.
- 0º and 45º preactivations (G1, G2) produce extrusive molar forces and intrusive premolar forces with distal moments.
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