Abstract
The purpose of this study was to analyze the relationship between the critical contact
angle and the torque angle in an orthodontic bracket and archwire assembly in 3 dimensions.
Three-dimensional mathematical models were created with geometric bracket-archwire
parameters that included 2 slot sizes, 3 bracket widths, and 3 to 4 wire sizes. From
this, 3-dimensional mathematical equations (3DMEs) for the critical contact angle
and the maximum torque that result in critical contact angles of 0 were derived and
calculated. To evaluate the effects of archwire-bracket parameters on critical contact
angles, analysis of variance (ANOVA) was performed at the significance level of P ≤.05. For all bracket-archwire combinations, the critical contact angle decreased
as bracket width, torque angle, and wire size increased. Therefore, all bracket-archwire
parameters except slot height had an effect on the critical contact angle. Results
of the critical contact angle produced from our 3DMEs were the same as those produced
by 3D computer-aided design (SolidWorks Corp, Concord, Mass), thus confirming the
validity of our derived equations. In addition, the effect of a beveled edge was investigated
in some archwires. Furthermore, torsional play angles were calculated and found to
be similar to those in previous reports. The results of this study provide theoretic
and experimental bases for clinical orthodontic practice and indicate that torque
angles should be included in the evaluation of the critical contact angle. (Am J.
Orthod Dentofacial Orthop 2003;123:64-73)
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References
- Frictional forces in fixed appliances.Am J Orthod Dentofacial Orthop. 1989; 96: 249-254
- Assessment of second-order clearances between orthodontic archwires and bracket slots via the critical contact angle for binding.Angle Orthod. 1999; 69: 71-80
- Influence of archwire and bracket dimensions on sliding mechanics: derivations and determinations of the critical contact angles for binding.Eur J Orthod. 1999; 21: 199-208
- A comparative study of frictional resistances between orthodontic bracket and arch wire.Am J Orthod. 1980; 78: 593-609
- Evaluation of friction between ceramic brackets and orthodontic wires of four alloys.Am J Orthod Dentofacial Orthop. 1990; 98: 499-506
- Influence of ceramic and stainless steel brackets on the notching of archwires during clinical treatment.Eur J Orthod. 2000; 22: 409-425
- Frictional coefficients of ion-implanted alumina against ion-implanted beta-titanium in the low load, low velocity, single pass regime.Dent Mater. 1992; 8: 167-172
- A comparison of the frictional characteristics of five initial alignment wires and stainless steel brackets at three bracket to wire angulations—an in vitro study.Br J Orthod. 1994; 21: 15-22
- Surface topography and frictional characteristics of ceramic brackets.Am J Orthod Dentofacial Orthop. 1994; 106: 76-87
- A study of frictional forces between orthodontic brackets and archwires.Br J Orthod. 1994; 21: 349-357
- The effect of artificial saliva on the frictional forces between orthodontic brackets and archwires.Br J Orthod. 1995; 22: 41-46
- The ex vivo effect of ligation technique on the static frictional resistance of stainless steel brackets and archwires.Br J Orthod. 1995; 22: 145-153
- Relative kinetic frictional forces between sintered stainless steel brackets and orthodontic wires.Am J Orthod Dentofacial Orthop. 1995; 107: 20-27
- Relative friction minimization in fixed orthodontic bracket appliances.Biomech. 1996; 29: 483-491
- Frictional resistance between orthodontic brackets and archwires in the buccal segments.Angle Orthod. 1996; 66: 215-222
- Evaluation of frictional resistance in esthetic brackets.Am J Orthod Dentofacial Orthop. 1997; 112: 138-144
- Friction between different wire-bracket configurations and materials.Semin Orthod. 1997; 3: 166-177
- A comparison of self-ligating and conventional orthodontic bracket systems.Br J Orthod. 1997; 24: 309-317
- Frictional forces related to self-ligating brackets.Eur J Orthod. 1998; 20: 283-291
- Friction in perspective.Am J Orthod Dentofacial Orthop. 1999; 115: 619-627
- Comparison of frictional resistance in titanium and stainless steel brackets.Am J Orthod Dentofacial Orthop. 1999; 116: 271-274
- Evaluation of friction during sliding tooth movement in various bracket-arch wire combinations.Am J Orthod Dentofacial Orthop. 1999; 116: 336-345
- The friction and wear patterns of orthodontic brackets and archwires in the dry state.Am J Orthod Dentofacial Orthop. 2000; 118: 662-674
- Sliding mechanics of coated composite wires and the development of an engineering model for binding.Angle Orthod. 2000; 70: 34-47
- Influence of angulation on the resistance to sliding in fixed appliances.Am J Orthod Dentofacial Orthop. 1999; 115: 39-51
- On mechanical properties of square and rectangular stainless steel wires tested in torsion.Am J Orthod Dentofacial Orthop. 1997; 111: 310-320
- Evaluation of titanium brackets for orthodontic treatment: Part II-the active configuration.Am J Orthod Dentofacial Orthop. 2000; 118: 675-684
- Frictional forces when rectangular guiding arches with varying edge bevel are employed.J Orofac Orthop. 1998; 59: 139-149
- On the variability of cross-sectional dimensions and torsional properties of rectangular nickel-titanium arch wires.Am J Orthod Dentofacial Orthop. 1998; 113: 546-557
- The effect of cross-sectional dimensional variations of square and rectangular chrome-cobalt archwires on torsion.Angle Orthod. 1998; 68: 239-248
- Torque transmission between square wire and bracket as a function of measurement, form and hardness parameters.J Orofac Orthop. 2000; 61: 258-265
Article Info
Publication History
Accepted:
April 1,
2002
Received in revised form:
April 1,
2002
Received:
December 1,
2001
Footnotes
*bAssistant Professor, Department of Orthodontics, College of Dentistry, Seoul National University, Seoul, Korea.
**cAssistant Professor, Division of Craniofacial Sciences and Therapeutics, School of Dentistry, University of Southern California, Los Angeles.
*dProfessor Emeritus, Department of Orthodontics, College of Dentistry, Seoul National University, Seoul, Korea.
**Reprint requests to: Seung-Hak Baek, DDS, MSD, PhD, Department of Orthodontics, College of Dentistry, Seoul National University, #28 Yeonkun-dong, Jongro-ku, Seoul, 110-749, South Korea; e-mail, [email protected] .
*0889-5406/2003/$30.00 + 0
Identification
Copyright
© 2003 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
