This document discusses dental hand instruments. It begins by defining instruments and their purposes. It then discusses the history and evolution of instruments from large, heavy designs to smaller, more precise tools. It categorizes instruments as cutting or non-cutting and describes common types like excavators, mirrors, and probes. It details the parts of instruments, materials used, and techniques for proper handling.

1. HAND
INSTRUMENTS
~ HARNI.N
III YEAR
ASAN MEMORIAL DENTAL
COLLEGE AND HOSPITAL

2. Introduction:
 • The term ‘instrument’ refers to a tool, device or
implement used for a specific purpose or type of work
and is preferred in professional or scientific fields as
precision items to perform specific procedures.
 • In order to perform the intricate or detailed
procedures associated with operative dentistry, the
dentist must have a complete knowledge of the
purpose and application of the many instruments
required.
 The instruments available
 The purpose of the instrument
 The position or manner of use
 The application of the instrument.

3. HISTORY:
 Most hand instruments of the
mid 19th century,
- Large, heavy handles and
inferior metal alloys .
- Cumbersome, awkward to use,
ineffective.
- No uniformity of manufacture
or nomenclature.

4. As cavitypreparationsrefinedandaccessto thevarioussurfacesof theteethdesired:
~ Grasp changed to pen grasp,
~ Instruments with large straight blades, changed to
smaller angular blades.

5. CLASSIFICATION OF HAND
INSTRUMENTS:
Accordind to sturdevant:
 Cutting instruments
 Non cutting instruments
 This classification was proposed by
G.V.Black.

6. CUTTING INSTRUMENTS
EXCAVATOR
1) ORDINARY
HATCHET
2) HOE
3) ANGLE
FORMER
4) SPOONS
CHISELS
1) CHISEL
2) ENAMEL
HATCHET
3) GINGIVAL
MARGIN
TRIMMER
OTHERS
1) KNIVES
2) FILES
3) SCALERS
4) CARVERS

7. NON CUTTING INSTRUMENTS
- Amalgam
condensers
- Mirrors
- Explorers
- Probes
- Others

9. MATERIALS USED
CARBON STEEL
• More corrosion tendency.
• Harder than stainless steel.
STAINLESS STEEL
• Less corrosion tendency.
• It loses keen edge quicker during much use.
Stellite
• High resistance to acid
• Hardness
*Alloys of nickel, cobalt or chromium are also used

10. PARTS OF HAND
INSTRUMENTS:
Most of the instruments are composed of
the following parts:
• Handle
• Shank
• Blade/Nib

12. HANDLE
• It is used to hold
the instrument.
• They are available
in various sizes and
shapes.
SHANK
• It connects the handle
with the working point
or nib of the instrument.
• It is smooth, round or
tapered.
BLADE/
NIB
• Working part of the
instrument.
• Connected to the
handle by
shank.

13. NAMES
 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,
binangle
 spoon excavator

15. INSTRUMENT FORMULAS
 Hand cutting instruments have formulas
describing the dimensions and angles of
working end.
 Placed on the handle as code of three or four
numbers separated by dashes or spaces.

16. 1. Width of the blade
in 1/10 of a mm.
2. Primary cutting edge
angle-
Measured from line parallel to
Long axis of handle in
clockwise
centigrade in percent of 3600
eg:- 85= 85% x 360= 3060
• If edge is perpendicular to
blade,
this number is omitted
3. Blade length- in mm
4. Blade angle- relative to long
axis of handle in clockwise
centigrade

17. 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 3
directions; facial and lingual
walls of the proximal cavity.

18. CUTTING INSTRUMENTS
 CHISELS:
 • Used primarily for cutting enamel
 • Used with push motion.
 • They are grouped as:
 Straight, slightly curved or binangle
 Enamel hatchets
 Gingival margin trimmer

20. 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.

21. GINGIVAL MARGINAL 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.

22. 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.

23. Ordinary hatchet excavator
 Cutting edge of blade directed in the same plane as
that of the long axis of the handle and is bibevelled.
 Used primarily on anterior teeth for preparing retentive
areas and sharpening internal line angles, particularly
in preparations for direct gold restorations.

24. 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.

25. 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.

26. 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.

27. CLEOID DISCOID

28. Other cutting instruments
KNIVES-
• finishing knives,
amalgam knives or
gold knives designed
with thin knife-like
blade.
• For trimming excess
restorative material
on the gingival, facial
or lingual margins of
a proximal
restoration.

29. FILES
 • To trim excess restorative material
 • Particularly useful at gingival margins
 • Blades are very thin & short teeth on cutting
surfaces
 • Either push or pull instrument

30. DISCOID-CLEOID
 • Used principally for carving occlusal
anatomy in unset amalgam restorations
 • To trim/ burnish inlay-onlay margins

31. DIAGNOSTICINSTRUMENTS
 MOUTH MIRROR:
 • To reflect light in the mouth
 • To retract lips, cheeks, and
tongue
 • To provide indirect vision

32. EXPLORER
 • It is used to examine
caries, calculus,
furcation.
 • Variety of sizes and
types
 Orban
 Pigtail
 Shepherd’s hook

33. AMALGAMCONDENSER
 • Used to pack and condense amalgam into
cavity preparation
 • Single or double sided
 • Smooth or serrated ends
 • Round or flat
 • Small or large sizes

34. PROBE
 Used to measure the
sulcus or pocket
depth of the
periodontium of each
tooth.
 This measurement
provides the clinician
with overall gingival
health of that area.

35. Handinstrument techniques
 • Modified pen
 • Inverted pen
 • Palm and thumb
 • Modified palm and thumb

36. Modified pen grasp
 Pads of thumb, index and middle finger
contact instrument, while tip of the ring finger
and/or little finger is placed on a nearby tooth
of the same arch as REST.

37. Invertedpen grasp
 • Hand rotated so that palm faces more
toward the operator.
 • Used mostly for tooth preparations utilizing
lingual approach on anterior teeth.

38. Palm andthumb grasp
 Handle placed in the palm of the hand and
grasped by all the fingers, while thumb is free
of the instrument and rest provided by tip of
thumb on nearby tooth of same arch or on a
firm, stable structure.

39. Modified palmand thumb grasp
 • Used when its feasible to rest the thumb on the tooth
being prepared or the adjacent tooth
 • Used universally

40. RESTS
 INTRA-ARCH HARD TISSUE REST:
 In modified pen grasp and inverted pen grasp,
rests are established by placing ring or ring
and little fingers on tooth of the same arch
and as close to operating site as possiblE.

41. SOFT TISSUE REST
 Soft tissue rest or too distant hard tissue rest
does not afford a reliable control.
INDIRECT REST
 When it is impossible to establish normal
finger rests with the hand holding the
instrument, instrument control maybe gained
using forefinger of the opposite hand on the
shank of the instrument.

43. GUARDS
 The use of interproximal wedges to protect
soft tissues from contact with sharp rotary
cutting instruments.