Oral Biology Research

Table. 1.

The average force, hysteresis and unload/peak ratio during repeated extension of Generation II power chain (Ormco, Glendora, CA, USA) and the percentage of the residual force to the force at the first extension

Cycle 12.5 mm peak 11.5 mm load 1 mm unload Hysteresis 1-mm-unload/peak ratio
1st cycle 378.2±11.3a 365.1±10.6a 309.6±8.5a 55.6±2.5a 81.9±0.41%d
100% 100% 100% 100%
2nd cycle 365.5±10.9b 332.5±9.5b 303.2±8.4b 29.3±1.5b 83.0±0.42%c
96.6±0.33% 91.1±0.46% 97.9±0.45% 52.8±2.2%
3rd cycle 358.6±10.1c 323.1±9.3c 299.8±8.4c 23.6±1.5c 83.5±0.38%b
94.8±0.42% 88.5±0.46% 96.7±0.45% 42.5±2.1%
4th cycle 354.3±10.5d 318.1±9.3d 297.0±8.5d 21.2±1.4d 83.8±0.36%a
93.7±0.37% 87.1±0.40% 95.9±0.48% 38.1±1.8%
5th cycle 351.2±10.4e 314.6±9.0e 295.1±8.7e 19.5±1.3e 84.0±0.35%a
92.9±0.42% 86.2±0.45% 95.3±0.56% 35.1±2.7%

Values are presented as mean±standard deviation. Unit: gram-force (gf).

a,b,c,d,eDifferent letters indicate significant statistical differences among cycles (p<0.05, Tukey HSD test).

Oral Biol Res 2022;46:71~77 https://doi.org/10.21851/obr.46.02.202206.71
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