Advantages of the self-ligating or ligatureless SS bracket vs the conventional SS bracket and SS ligature at θ ≤ θ_c. When properly used at θ ≈ θ_c, the self-ligating SS bracket outperforms the conventional appliance. If θ >> θ_c, however, any relative advantage substantially disappears (G. A.Thorstenson and R. Kusy, in preparation). Conditions for the self-ligating system: AWs = 18 × 25 mil SS (Ormco); BRs = 22 mil SS (Damon SL, Ormco); state = dry; temperature = 34°C; N_FR = 300 cN; IBD = 18 mm. Conditions for the conventional SS system: AWs = 18 × 25 mil SS (Ormco); BRs = 22 mil SS (Mini Diamond Twin, Ormco); ligatures = 10 mil SS (PL1010 ligature, GAC); state = dry; temperature = 34°C; N_FR = 300 cN; IBD = 18 mm