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A new method to evaluate the positional stability of a self-drilling miniscrew
1Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing, China.
Orthodontics & Craniofacial Research
|February 24, 2015
Summary
Miniscrews used in orthodontic treatment, including those loaded for tooth movement and unloaded ones, demonstrated excellent positional stability. Cone-beam computed tomography (CBCT) confirmed their stability throughout the en-masse retraction phase.
Area of Science:
- Orthodontics
- Dental Implantology
- Biomaterials
Background:
- Miniscrews are widely used as orthodontic anchorage devices.
- Assessing the long-term positional stability of miniscrews is crucial for predictable treatment outcomes.
- Cone-beam computed tomography (CBCT) offers precise three-dimensional imaging for evaluating miniscrew stability.
Purpose of the Study:
- To evaluate the positional stability of loaded and unloaded orthodontic miniscrews.
- To assess miniscrew stability during the en-masse retraction phase of orthodontic treatment.
- To utilize cone-beam computed tomography (CBCT) for quantitative positional analysis.
Main Methods:
- Twenty adult volunteers with maxillary first premolar extractions were included.
- Six miniscrews were placed in the maxilla per volunteer (two loaded, four unloaded).
- CBCT scans were taken at the start (T1) and end (T2) of space closure, with 3D models and PCA analysis used to measure angle change.
Main Results:
- The mean angle change for unloaded miniscrews was 1.64 ± 1.25°.
- The mean angle change for loaded miniscrews was 1.67 ± 1.15°.
- No statistically significant difference in angle change was observed between loaded and unloaded miniscrews.
Conclusions:
- Both loaded and unloaded miniscrews exhibited positional stability during en-masse retraction.
- CBCT imaging confirmed the reliable performance of miniscrews in this orthodontic context.
- Miniscrews can be considered a stable anchorage option for orthodontic tooth movement.
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