The document discusses the parts and functions of various dental instruments. It describes the typical components of hand instruments which include the shaft, shank, and blade. It then explains the dimensions and angles used to code instruments, such as blade width and cutting edge angle. Finally, it provides details on specific instruments used for examination, cutting, restoration, and finishing procedures in dentistry.

2.  Every hand instrument has the
following parts:
 The shaft, which is used as a handle,
is straight and is usually without
variation in size. It may be serrated to
increase friction for hand gripping.
 The shank, which connects the shaft
with the blade or working point. It
usually tapers from its connection
with the shaft to where the blade
begins.
 The blade is the part of the
instrument bearing the cutting edge.
It begins at the angle if one angle is
present in the shank; or at the last
angle, if more than one angle is
present in the shank; or at the point
which terminates the shank . The
blade ends in the cutting edge.

3. The blade angle is defined
as the angle between the
long axis of the blade and
the long axis of the shaft.
The cutting edge is the
working part of the
instrument. It is usually in
the form of a bevel with
different shapes.
The cutting edge angle is
defined as an angle between
the margin of the cutting
edge and the long axis of
the shaft.

4. (1) – Blade width
(2) - Cutting edge angle
(3) - Blade length
(4) - Blade angle
EXAMPLE

5.  Cutting instruments have formula describing the dimensions and angles
of the working end. These are placed on the handle using a code of
three or four numbers separated by dashes or spaces (e.g. 10-85-8-
14).
 The first no. indicates the width of blade or primary cutting edge in
tenths of a millimeter(0.1mm) (e.g.10=1mm).
 The second number of a four number code indicates the primary cutting
edge angle measured from a line parallel to the long axis of the
instrument handle in clockwise centigrade. The angle is expressed as a
percent of 360 degrees (e.g. 85= 85% x 360 degrees= 306 degrees).If
the edge is locally perpendicular to the blade, this number is normally
omitted, resulting in a three-number code.
 The third number (second number of a three-number code) indicates
the blade length in millimeter (e.g. 8=8mm).
 The fourth number (third number of a three number code) indicates the
blade angle relative to the long axis of the handle in clockwise
centigrade (14=50 degrees ).

6.  EXPLORING INSTRUMENTS
 Mouth mirror
 Tweezers
 Probes/explorers
 Instruments for tooth structure removal
 Hand cutting instruments
1. Excavators : Hatchet, hoes, spoon, angle formers
2. Chisels : straight, monoangle, biangle, and triple angle
3. Special forms of chisel : enamel hatchets, gingival marginal trimmers
 Rotary cutting and abrasive instruments
1. Handpiece
2. Burs
3. Ultrasonic instruments

7.  RESTORING INSTRUMENTS
 Mixing instruments : stainless steel or plastic spatula
 Condensing instruments : rounded, triangular, diamond, or parallelogram
condensers
 Burnishing instruments : ball/ egg/ conical-shaped burnishers
 Carvers: Hollenback's discoid and cleoid, diamond shaped carvers
 Files : hatchet
 Knives : bard parker knife and stein’s knife
 FINISHING AND POLISHING INSTRUMENTS
 Burs, stones, brushes, rubber (wheel, cups or cones), cloth or felt

8. • Mouth mirrors are used as
supplement to improve
access to instrumentation.
• Used to reflect dental light
on to a specific area of oral
cavity.
• It is used for retraction of
soft tissues such as the
cheeks and the tongue to
aid in better visualization of
the operating field.
• Mirror is placed in oral
cavity that cannot be seen
directly without
compromising dentist’s
position.
MOUTH MIRROR

9. •These have angled tip
and are available in
different sizes.
• They are used to
place and remove
cotton rolls and other
small materials.
• It comes in different
sizes to fit various
needs.
TWEEZERS

10. •The probe is used for the
identification of tooth
lesions.
•There are 4 types of
explorers used in dentistry:
1. STRAIGHT EXPLORER
2. RIGHT-ANGLED EXPLORER
3. ARCH EXPLORER
4. INTERPROXIMAL EXPLORER
PROBE

11. • Any instrument where the cutting
edge is parallel or close to parallel to
the plane of the instrument is called
hatchet.
• Hatchet is a paired instrument in
which blade makes 45 or 90 degree
angle to the shank.
• In paired right and left hatchets,
blades are beveled on opposite sides
to form their cutting edges.
• Hatchets are used for cleaving
enamel and walls so as to have sharp
outline of the preparation.
HATCHET

12. • Chisels are used for cleaving,
planning and lateral scraping.
• They are used to split tooth
enamel, to smooth preparation
walls and to sharpen the
preparations.
• Chisels are used with a push
motion.
• Chisels are of 4 types :
1. STRAIGHT CHISEL
2. MONOANGLE CHISEL
3. BINANGLE CHISEL
4. WEDELSTAEDT CHISEL
CHISELS

13. •The gingival margin trimmer
(GMT) is a modified hatchet
which has working ends with
opposite curvatures and
bevels.
• The GMT is available in a set
of two double ended styles
and is used in pairs. The
distal GMT is used for the
mesial surface.
• GMT is used for planning
gingival cavosurface margin
that is removal of
unsupported enamel and to
bevel axiopulpal line angle in
classII tooth preparation
GINGIVAL MARGINAL TRIMMER

14. • Dental hoe resembles
a miniature garden
hoe.
• The blade makes
more than 45 to 90
degree angle to the
long axis of the
handle.
• Hoe is used with a
pulling motion.
• Hoe is use to shape
and smoothen the floor
and form line angles in
class III and V
restorations.
HOE

15. • They are use to deliver and
condense the restoration to
the tooth preparation.
• The hammer like working
end of condenser should be
large enough to pack
restoration.
• It comes in single and
double ended designs.
• They are available in
differently shaped and sized
working ends like round,
triangular or parallelogram,
which may be smooth or
serrated.
CONDENSER

16. • Amalgam carriers carry
the freshly prepared
amalgam restorative
material to the prepared
tooth.
• It have hollow working
ends called barrels into
which the amalgam is
packed for
transportation.
• It can be single and
double ended.
AMALGAM CARRIERS

17. •It makes the surface shiny by
rubbing.
• They are used to smoothen and
polish the restoration and to
remove scratches present on the
amalgam surface after its
carving.
• It have smooth rounded working
ends and come in single and
double ended types.
BALL BURNISHER

18.  Rotary cutting instruments are
those instruments which rotate
on an axis to do the work of
abrading and cutting on tooth
structure.
 Types of rotary cutting
instruments:
 Handpiece : It is a power device
- Straight hand piece
- Contra-angle handpiece
 Bur : It is a cutting tool.

19.  According to their mode of attachment to hand piece:
 Latch type
 Friction type
 According to their composition:
 Stainless steel burs
 Tungsten carbide bur
 Combination of both
 According to their motion:
 Right bur
 Left bur
TUNGSTEN CARBIDE BURS

20.  According to the length of their
head:
 Long
 Short
 Regular
 According to their use:
 Cutting burs
 Finishing burs
 Polishing burs
 According to their shapes:
 Round bur
 Inverted cone
 Pear-shaped
 Wheel shaped
 Tapering fissure

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