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Updated: Aug 8, 2026
04:11
The Establishment of a Murine Maxillary Orthodontic Model
Published on: October 27, 2023
Leveling of the second molar with a superelastic spring
Christian Sander1, Franz Martin Sander, Franz Günter Sander
1University of Ulm, Department of Orthodontics, Oberer Eselsberg, 89081, Ulm, Germany. guenter.sander@uni-ulm.de
Summary
A novel superelastic segmental archwire effectively aligns second permanent molars during orthodontic treatment. This method uses moderate forces to intrude, derotate, and upright molars without causing bite opening.
Area of Science:
- Orthodontics
- Biomaterials Engineering
Background:
- Second permanent molars frequently erupt during orthodontic treatment with fixed appliances.
- Bonding buccal tubes to erupting second molars in the correct position can be challenging.
Purpose of the Study:
- To present a method for aligning second permanent molars using a superelastic segmental archwire.
- To evaluate the forces and moments generated by different archwire materials for molar alignment.
Main Methods:
- A superelastic segmental archwire was employed for aligning second permanent molars.
- In-vitro testing with a hexapode simulated molar vertical deviation.
- Clinical application of the described method was investigated.
Main Results:
- Stainless steel and TMA archwires generated high forces (13 N and 5 N) and moments (55 Nmm and 25 Nmm).
- The superelastic late-leveler produced significantly lower forces (1.3 N) and moments (4 Nmm) at greater deflection (5 mm).
Conclusions:
- High forces/moments from stainless steel and TMA archwires are unsuitable for second molar alignment.
- The superelastic late-leveler provides controlled forces for intrusion, derotation, and uprighting.
- The archwire's vertical component effectively prevents iatrogenic bite opening.
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