The gingival margin trimmers (GMTs) (fig. 4) are modified hatchets that have working ends with opposite curvatures and bevels. As the name implies, GMTs are used to trim, smooth, and shape the gingival floor of a cavity preparation.GMTs are available in double-ended styles and are used in pairs, such as the #26 and #27. This is because the working ends of the even-numbered instruments are designed for use on the distal surfaces, and the odd numbered are used on the mesial surfaces.
