Standard Gracey curettes are designed for light to moderate scaling and subgingival and root debridement. Often the flexibility of the shank of the Standard Gracey does not aid in scaling heavy calculus (when power scaling cannot be utilized). Rigid and Extra Rigid designs can accommodate these scaling needs (Figure 20).
The Rigid Gracey curette is designed for moderate calculus removal and root debridement as well as periodontal surgery. It has the same shank angulation and blade width as the standard Gracey, but the shank is wider and thus a little more rigid.
The Extra Rigid Gracey curette is designed for heavy calculus removal, gross scaling and debridement and periodontal surgery. It has the same shank width and blade as the Rigid Gracey, but the shank has unique angles and bends to aid in access to areas of the mouth (Figure 21).