Principles of Instrumentation Flashcards
Fulcrum=
Finger rest
Adaptation=
Rotation or rolling
*keeping the SIDE of the last 2mm of the working end on the tooth
Place the terminal shank _____ to the surface to be instrumented
Parallel
______ of tip adapted to conform to contour of surface
Side
*not middle or toe/tip
Tip should be pointed in the direction of the stroke; pointed distally if going ____, mesial if going _____
Distal, mesial
Scaler and curette surfaces:
Face, back, laterals, 2 CE’s
The shank-
Connects the handle with the working end. Allows for adaptation of the working end to the tooth surface; may be angles, curved, or straight.
_______ of the shank reflect the intended use of the instrument
Design features
Diameter of instrument plays a role in ____ _____
Deposit removal
Thick diameter for ______
Heavier deposit
Thinner diameter for _______
Light deposit, root surface debridement
Rigidity is determined by ______
The shank
Grasp=
Stabilization
Long shank are for ______ teeth
Posterior
Shorter shank for _______ teeth
Anterior
Straight shank=
Simple shank
Multiple bends in shank=
Complex shank
Terminal shank=
KEY POINT
Portion of the shank closest to the blade
Terminal shank
Part which contacts tooth that does the work
Working end
*sharp cutting edge
Cross sectional shapes:
Half moon, half circle- curette
Triangular- scaler
Cylindrical- probe
Trapezoid- file, hose, chisel
Tips:
Blunt- probe
Sharp pin point- explorer
Rounded toe- curette
Back:
Angled/point- slightly sub
Rounded- meant to go deep in tissues
Working end ____ be perpendicular to the shank _____ degrees
May, 90
May be offset at an angle to the shank: _____ degrees
60-70 degrees
Blade size refers to ____ and _____
Width and thickness
Width- from cutting edge to cutting edge
Thickness- from face to back
Scalers are:
Paired or unpaired?
Unpaired
Scaler design features:
Pointed tip Triangle cross section C-sickle or jacquette 2 cutting edges 90 degree shank
Curette design features:
2 CE's 1/2 moon 60-70 degree gracey, 90 universal Rounded toe- sub Looks like spoon to scoop up debris All paired
Gracey curette design features:
60-70 degree to terminal shank 1 useful cutting edge Area specific Shanks=long rigid, flexible Curved in 2 places, length wise and to side
Advantages of gracey curettes
Specific surfaces
Longer shank
Round back
Incidental curettage
Universal curette
design features:
Advantages:
90 degrees to terminal shank and face
Each end has 2 CE’s
Each end mirror images to each other
Rigid shank
Less time because used everywhere
Instruments for detection and assessment
Explorer and probe
Instruments for scaling and root debridement
Scaler and curette
Working angulation (sub and supra)
60-80 degrees
Stroke directions
Vertical or oblique
