Curved Sickle scalers have two cutting edges. These cutting edges are formed by the junction of the facial surface of the blade with the two lateral surfaces. The two cutting edges converge at the end of the instrument to form a sharp, pointed tip.
The sickle scaler has an almost pointed back and the cross-section view reveals a triangular shape.
Straight sickle scalers, such as a Jacquette scaler, also have two cutting edges that come to a point at the tip of the blade.
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