hand instruments
TRANSCRIPT
HAND INSTRUMENTS
PRESENTED BY:FASAHAT AHMED BUTT
ROLL# 36GROUP: C
CLASSIFICATION
• Cutting instruments
• Non cutting instruments
CUTTING INSTRUMENTS
EXCAVATOR CHISELS OTHERS
1) ORDINARY HATCHET2) HOE3) ANGLE FORMER4) SPOON
1) CHISEL2) ENAMEL HATCHET3) GINGIVAL MARGIN TRIMMER
1) KNIVES2) FILES3) SCALERS4) CARVERS
NON CUTTING INSTRUMENTS
1) MIRROR2) PROBE3) TWEEZER
Diagnostic instruments Plastic instruments
Amalgam instruments
1) DYCAL APPLICATOR2) CEMENT SPATULA
1) AMALGAM CARRIER2) CONDENSER3) BURNISHER4) CARVER
MATERIALS USED
CARBON STEEL• More corrosion
tendency.• Harder than
stainless steel.• It loses keen edge
slower than stainless steel.
STAINLESS STEEL• Less corrosion
tendency.• Less comparatively.• It loses keen edge
quicker during much use.
PARTS OF HAND INSTRUMENTS
• Most of the instruments are composed of the following parts:
• Handle• Shank• Blade/Nib
HANDLE
• It is used to hold the instrument.• They are available in various sizes and
shapes.• It may be smooth or eight sided and
serrated.• On handle of the instrument, the
instrument formula and manufacturer’s name are written.
SHANK
• It connects the handle with the working point or nib of the instrument.• It is smooth, round or tapered.• It may be straight or bent for better
control of working point when the force is applied.• It has one or more angles to avoid
twisting of the instrument.
BLADE
• Working part of the instrument.
• Connected to the handle by shank.
• Each blade has a cutting edge that is the working end.
BLACK’S CLASSIFICATION• Black classified all instruments according
to:
• FUNCTION: Excavator.• MANNER OF USE: Hand condenser.• DESIGN OF WORKING END: Hatchet• SHAPE OF THE SHANK: Mono-angle, bin
angle, contra-angle.• These names were combined to form the
complete description of the instrument e.g, bin-angle spoon excavator
INSTRUMENT FORMULA
• Hand cutting instruments have formulas describing the dimensions and angles of working end. Placed on the handle as three or four figures.
THREE-NUMBER FORMULA
• For instruments in which the primary cutting edge is at a right angle to the long axis of the blade.
14-10-16
• 14: Width of the blade (in tenths of mm)
• 10: Length of the blade (in mm)• 16: Angle (in centigrade) made by
long axis of the blade and the long axis of the handle
FOUR-NUMBER FORMULA
15-95-10-7
• 15: Width of the blade (in tenth of mm)
• 95: Primary cutting edge angle (in centigrade)• 10: Length of the blade (in mm)• 7: Angle the blade makes with the long axis of the handle (in centigrade)
BEVEL
• Most cutting instruments have on the end of blade a single bevel that forms the primary cutting edge.• Additional two bevel extends from
primary cutting edge for the length of the blade.• This allows cutting in three dimensions.
CUTTING INSTRUMENTS
CHISELS:• Used primarily for cutting
enamel• Used with push motion.• They are grouped as: Straight, slightly curved or
bin-angle Enamel hatchets Gingival margin trimmer
ENAMEL HATCHET• Used primarily in anterior teeth, for
preparing retentive areas and sharpening internal line angles.
• To remove unsupported enamel• It comes as right and left types for use
on opposite sides of the preparation• Used with push, pull & vertical motion.
GINGIVAL MARGIN TRIMMER
• It is used to trim, smooth, and shape the gingival floor of a cavity preparation.
• It is also used for rounding or beveling of the axiopulpal line angle.
• Used with lateral scraping motion.
HOE
• Used to clean and smooth floor and walls in cavity preparation and forming line angles.
• Used with a pulling motion• Cutting edge or blade nearly perpendicular to
handle.
HOE VS HATCHET
• If the angle of the blade is less than 12.5 centigrade, it is mono-angle chisel & if it is more than 12.5 centigrade, it is hoe.
ANGLE FORMERS
• Primarily used for sharpening internal line angles and creating retentive features in dentine in preparation for gold restorations.
• Used in 3 motions vertical, push and pull.
SPOON EXCAVATOR
• Used to remove Soft carious dentine Temporary crowns Temporary cement in temporary restoration Permanent crown during try-in
• Discoid: Cutting edges are circular• Cleoid: Cutting edges are claw like
NON-CUTTING INSTRUMENTS
DIAGNOSTIC INSTRUMENTS
MOUTH MIRROR:
• To reflect light in the mouth• To retract lips, cheeks, and tongue• To provide indirect vision
DENTAL EXPLORER
• It is used to examine caries, calculus, furcation.
• Variety of sizes and typesOrbanPigtailShepherd’s hook
TWEEZER (cotton forceps)
• To grasp or transfer items and/or material into and out of the oral cavity.
• Plain or serrated tips.• Pointed or rounded tips
Locking tweezer
PLASTIC INSTRUMENTS
DYCAL APPLICATOR
• To place calcium hydroxide or glass ionomer in cavity preparation.
CEMENT SPATULA
• It is used for mixing cements and carrying materials.
AMALGAM INSTRUMENTS
• AMALGAM PLUGGER
• To carry and dispense amalgam for cavity preparation
• Single or double ended
AMALGAM INSTRUMENTS
CONDENSER
• Used to pack and condense amalgam into cavity preparation
• Single or double sided • Smooth or serrated ends• Round or flat• Small or large sizes
BURNISHER
• Used to smooth amalgam after condensing.
• Burnish amalgam.
• It is also used to contour matrix band before placement.
• It may be single or double ended.
CARVER
• To carve occlusal anatomy into amalgam restoration
• Single or double ended.
HAND INSTRUMENT TECHNIQUES
• Modified pen• Inverted pen• Palm and thumb• Modified palm and thumb
MODIFIED PEN
INVERTED PEN
PALM AND THUMB
MODIFIED PALM AND THUMB
REFERENCES
• Summit• Art and science• Google