The Expansion ‘W’ and its Modification in Orthodontic Treatment

Abstract

A quad helix expansion device is described and modifications shown which increase its range of action.

A randomized controlled trial comparing the quadhelix and the expansion arch for the correction of crossbite

“…The quadhelix is a W-shaped arch with four helical loops that is inserted into sheaths on the palatal aspects of the upper first molar bands. 20 Those used in the present study were preformed in 0.9 mm stainless steel wire ( Figure 1; 3M Unitek, PO Box 1, Bradford, West Yorkshire BD5 7BR, UK).…”