trimmer, gingival margin

trimmer, gingival margin,

n (margin trimmer), a binangled, double-paired, chisel-shaped, single-beveled, double-planed lateral cutting instrument. The blade is curved left or right similar to a spoon excavator; the cutting edge is straight and not perpendicular to the axis of the blade. The pair with the end of the cutting edge farthest from the shaft forming an acute angle is termed
distal and is used to bevel a distal gingival margin or accentuate a mesial axiogingival angle; the pair with the acute angle of the cutting edge closest to the shaft is called
mesial and is used to bevel a mesial gingival margin or accentuate a distal axiogingival angle. When one of these trimmers is used, all four must be used.

Gingival margin trimmer.