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Are torque values of preadjusted brackets precise?
Alessandra Motta Streva1, Flávio Augusto Cotrim-Ferreira, Daniela Gamba Garib
1Department of Orthodontics, Dental School, University of São Paulo, São Paulo, SP, Brazil. amstreva@yahoo.com.br
Journal of Applied Oral Science : Revista FOB
|September 30, 2011
Summary
Torque precision varies significantly among metallic orthodontic brackets from different brands. Some brands show significant deviations, potentially impacting final tooth positioning in orthodontic treatments.
Area of Science:
- Orthodontics
- Biomaterials Science
- Dental Mechanics
Background:
- Torque control is crucial in orthodontic treatment for precise tooth positioning.
- Metallic brackets with MBT (McLaughlin, Bennett, and Trevisi) prescription are widely used.
- Variations in bracket manufacturing can lead to inaccuracies in applied torque.
Purpose of the Study:
- To evaluate the torque precision of metallic canine brackets from six commercial brands.
- To compare measured torque values against the MBT prescription standards.
- To identify brands with significant torque deviations.
Main Methods:
- Six commercial brands of maxillary and mandibular canine brackets were selected.
- Torque angles were measured using an optical microscope and computer analysis.
- Measured values were compared to MBT prescription specifications.
Main Results:
- Morelli maxillary canine brackets showed a statistically significant difference in torque (-3.33º) compared to the MBT standard (-7º).
- American Orthodontics (-6.34º) and Ortho Organizers (-6.25º) mandibular canine brackets significantly differed from the MBT standard (-6º).
- Morelli exhibited significant torque differences compared to other brands for maxillary canines, but no inter-brand differences were found for mandibular canines.
Conclusions:
- Significant variations in torque values exist among assessed metallic orthodontic brackets.
- These torque inaccuracies could clinically compromise the buccolingual tooth alignment at the conclusion of orthodontic therapy.
- Dentists should be aware of potential torque discrepancies when selecting brackets.
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