Objective

To compare the resistance to sliding among different self-ligating brackets in dry and wet states.

Methodology

Resistance to sliding was investigated for three self-ligating brackets with active clips (In-Ovation®, Time®, SpeedT) and one self-ligating bracket with a passive slide (DamonT). For all cases, an .018 x .025 stainless steel archwire was drawn through each bracket at a rate of 10 mm/min over a distance of 2.5 mm. For each bracket, the resistances to sliding were measured at 14 different second-order angulations, which ranged from -9° to +9°. Both the dry and the wet (human saliva) states were evaluated at 34°C.

Resistance to Sliding (RS)

Resistance to Sliding (RS)

Damon is a trademark of Ormco Corp., Time is registered by American Orthodontics, Speed is a trademark of Strite Industries and In-Ovation is registered by GAC International, Inc.

Results

The bracket with a passive slide (Damon) exhibited negligible friction; brackets with active clips (In-Ovation, Time, Speed) exhibited frictional forces as great as 50 grams. In the passive configuration, the bracket with a passive slide exhibited small to no resistance to sliding in either the dry or wet states.

Conclusion

Of all self-ligating brackets tested, the one with a passive slide (Damon), produced the least resistance to sliding in both dry and wet states.