The effect of single plane curvature on half-round cast clasps

The quality of retention produced by a half-round cast clasp is affected by its curvature in the plane of its flat side. Uncurved clasps and those that curve 90 degrees, 180 degrees, and 270 degrees become progressively stiffer. Conversely, as the radius of the curvature increases, so does the flexibility of the clasp.