Comparison of T-Loop vs Opus Loop in Canine Retraction Efficacy and Anchorage Loss Control – A Split- Mouth Randomized Clinical Trial

Authors

  • Ayesha Ashraf Khan Author
  • Sarah Irfan Author
  • Tabassum Ahsan Bahria University Health Sciences, Campus, Karachi Author
  • Maria Moin Author

DOI:

https://doi.org/10.51985/

Keywords:

anchorage loss, angulation, canine retraction, Opus loop, T-loop

Abstract

 Objective: The primary aim was to compare the rate of canine retraction between T loop and Opus loop. The secondary objectives were to compare the angulation of canine, anchorage loss and molar rotation for the two loops used. Study Design and Setting: A Split- Mouth Randomized Clinical Trial done at Department of Orthodontics, Bahria University of Health Sciences Campus Karachi

 

Methodology: This study conducted including 14 participants who received both the Opus loop and T-loop in different quadrants. The primary outcome assessed was rate of canine retraction which was measured clinically at every appointment using calibrated calliper. Secondary outcomes included changes in canine angulation, anchorage loss and molar rotation. Canine angulation was measured using periapical radiographs of maxillary canine to 1st molar taken by DIGORA™ Optime at the start of canine retraction and after completion of canine retraction. Anchorage loss and molar rotation was measured by model analysis. For statistical analysis non-parametric test Wilcoxon signed-rank test was used to compare the treatment changes between Opus loop and T-loop.

 

Result: rate of canine retraction was higher in Opus loop (1.5 mm/month) compared to T-loop (1.45 mm/month) however no statistically significant differences between was found in rate of canine retraction, angulation change, anchorage loss, or molar rotation (p > 0.05), indicating comparable clinical performance of both mechanics during space closure. Conclusion: Both loops showed similar efficacy during canine retraction. 

References

1. Ribeiro GL, Jacob HB. Understanding the basis of space

closure in Orthodontics for a more efficient orthodontic

treatment. Dent Press J Orthod. 2016;21:115–25.

2. Barsoum HA, ElSayed HS, El Sharaby FA, Palomo JM,

Mostafa YA. Comprehensive comparison of canine retraction

using NiTi closed coil springs vs elastomeric chains: a splitmouth randomized controlled trial. Angle Orthod.

2021;91(4):441–8. DOI: https://doi.org/10.2319/110620-916.1

3. Trpevska V, Tanatarec I, Srbinoska D, Mijoska A. Straight

wire and segmented technique in canine retraction: case

reports. Arch Public Health. 2022;14:1. DOI: https://doi.org/

10.3889/aph.2022.6024

4. Nandan H, Kumar CS, Jha P. Comparison of maxillary canine

retraction using split-mouth design with dual force cuspid

retractor and T-loop segmental arch: a split-mouth randomized

clinical trial. Cureus. 2023;15(2).

5. Davis S, Sundareswaran S, James J. Comparative evaluation

of the efficiency of canine retraction using modified Marcotte

and T-loop retraction springs – a split-mouth, randomized

clinical trial. J Orthod Sci. 2019;8:1–7.

6. Ozaki H, Tominaga JY, Hamanaka R, Sumi M, Chiang PC,

Tanaka M, et al. Biomechanical aspects of segmented arch

mechanics combined with power arm for controlled anterior

tooth movement: a three-dimensional finite element study. J

Dent Biomech. 2015;6:1–9. DOI: https://doi.org/10.1177/

1758736014566337

7. Techalertpaisarn P, Versus A. Mechanical properties of Opus

closing loops, L-loops, and T-loops investigated with finite

element analysis. Am J Orthod Dentofacial Orthop.

2013;143(5):675–8. DOI: https://doi.org/10.1016/ j.ajodo.

2013.01.011

8. Burstone CJ, Koenig HA. Optimizing anterior and canine

retraction. Am J Orthod. 1976;70(1):1–9. DOI: https://doi.org/

10.1016/0002-9416(76)90257-8

9. Kumari S, Niranjane P. Evaluation and comparison of momentto-force ratio of a new “PRP loop” with that of Opus loop

and L loop: a finite element method study. J Clin Diagn Res.

2023;17(5):ZC11–ZC15. DOI: https://doi.org/10.7860/

JCDR/2023/63343.179440. Geramy A, Mahmoudi R, Geranmayeh AR, Borujeni ES,

Farhadifard H, Darvishpour H. A comparison of mechanical

characteristics of four common orthodontic loops in different

ranges of activation and angular bends: the concordance

between experiment and finite element analysis. Int Orthod.

2018;16(1):42–59. DOI: https://doi.org/10.1016/j. ortho.2018.

01.011

11. do Amaral Ferreira M, Rodrigues FRM, Luersen MA, Borges

PC. Closing loops: geometry and mechanical properties – a

review. Orthod J Nepal. 2022;12(1):64–74.

12. Nanda R. Biomechanics in clinical orthodontics. Philadelphia:

Saunders; 1997.

13. Siatkowski RE. Continuous arch wire closing loop design,

optimization, and verification. Part I. Am J Orthod Dentofacial

Orthop. 1997a;112:393–402. doi:10.1016/S0889-5406(97)

70047-7 DOI: https://doi.org/10.1016/S0889-5406(97)70047-

7

14. Siatkowski RE. Continuous arch wire closing loop design,

optimization, and verification. Part II. Am J Orthod Dentofacial

Orthop. 1997b;112:487–95. doi:10.1016/S0889-5406(97)

70075-1 DOI: https://doi.org/10.1016/S0889-5406(97)70075-

1

15. Safavi MR, Geramy A, Khezri AK. M/F ratios of four different

closing loops: 3D analysis using the finite element method

(FEM). Aust Orthod J. 2006;22(2):121–6.16. Obaidi H, Sabah O. Evaluation of tipping, rotation and rate

of space closure of canine retraction by frictionless orthodontic

techniques (An in vitro study). Al-Rafidain Dent J. 2006;6(3):

30–7.

17. Barot M, Shah A, Hirani S, Thakore K, Desai S, Pancholi D.

Comparative evaluation of different loops for individual

canine and en-masse retraction: a finite element method (FEM)

study. Int J Health Sci. 2022;6(S1):3037–50. DOI: https://doi.

org/10.53730/ijhs.v6nS1.5302

18. Masaes MM, Burhan AS, Youssef M, Nawaya FR. T-loop

spring vs Ricketts maxillary canine retractor in canine retraction

efficacy and anchorage loss control: a cone-beam computed

tomography study. AJO-DO Clin Comp. 2022;2(1):26–40.

DOI: https://doi.org/10.1016/j.xaor.2021.12.001

19. Rodrigues EU, Maruo H, Guariza Filho O, Tanaka O, Camargo

ES. Mechanical evaluation of space closure loops in

orthodontics. Braz Oral Res. 2011;25:63–8. doi:10.1590/

S1806-83242011005000003

20. Sanjay N, Rajesh RN, Scindia R, Ajith SD. Space closure

with loop mechanics for treatment of bimaxillary protrusion:

a case report. J Int Oral Health. 2015;7(5):65–8.

21. Harada R, Yokoi Y, Kamoi A, Miyawaki R, Yoshida T,

Kawamura J, et al. Biomechanical analysis of extraction space

closure with various loop springs incorporated into an archwire.

Appl Sci (Basel). 2023;13(4):2616. doi:10.3390/app13042616

Downloads

Published

2026-07-01

Issue

Section

Original Articles

How to Cite

Comparison of T-Loop vs Opus Loop in Canine Retraction Efficacy and Anchorage Loss Control – A Split- Mouth Randomized Clinical Trial. (2026). Journal of Bahria University Medical and Dental College, 16(03), 663-668. https://doi.org/10.51985/

Similar Articles

11-16 of 16

You may also start an advanced similarity search for this article.