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1. Instruments and equipment for
tooth preparation
Dr. Mazen D Doumani

2. Hand instruments
General classification of instruments
Cutting hand instruments
excavators, chisels
Non-cutting hand instruments
amalgam condensers, mirrors, explorers, probes
A) Diagnostic instruments
B) Restoring instruments

3.  Instruments that are used by the hands.
Parts of the hand instruments
 Composed of 3 parts:Handle , shank , and blade(nib).
 Noncutting instruments:the part corresponding to blade
is termed Nib
 Blade on both ends of the handle are known double-
ended instruments
I. Hand instruments

4. Blade
Handle
(shaft)
Shank

5.  The handle is used to hold the instrument.
 Different sizes and shapes .
 It may be smooth or serrated.
 The number , series , manfacturer’s name are written
on the handle.
Handle(shaft)

7.  It connects handle with the working pointnib , blade
of the instrument.
 It tapers from the shaft down to the blade and is
normally smooth , round or taperd
 It may be straight or bent for better control of the
working point when force is applied.
 The working point should be within 3mm to the center
of the long axis of the handle.
shank

8.  According to the numbers of angles , the instruments are
classified as:
- Straight :no angle
- Mon-angle: one angle
- Bin-angle: two angles
- Triple-angle: three angles
 If the shank has more than one angle ,it is termed (contra-
angled).

9.  it is connected to the handle by the shank.
 For cutting instrument, the working point is called blade.
 For non cutting instrument, the working point is called nib.
 If the blade is only in one end it is called single ended instrument.
 If the blade is only in two ends it is called double ended instrument.
Working point :Blade(nib)

10.  Most blades have three bevels :
- one on the end of the blade forming the primary cutting edge.
- two along the side of the blade forming the secondary cutting
edge .
- the instrument is called bi-beveled instrument .
Working point :Blade(nib)

11. 1- function (scaler , excavator).
2- manner of use (hand condenser).
3- design of the working end (spoon excavator , sickle scaler).
4- shape of the shank (mon-angle,bin-angle).
5- these names were combined to form the complete description
of the instrument:bin-angle spoon excavator
Black’s classification system by instrument
name categorized instruments by

12. Dr. G. V. Black classified instruments according to order
names, suborder names, class names, and subclass names.
Order names :denote the purpose for which the instrument
is to be used, such as mallet or clamps.
Suborder names :define the manner or position of use of the
instrument, such as hand mallet or molar clamps.
Class names: describe the working point of the instrument,
such as spoon excavator or inverted cone bur.
Subclass names: indicate the angle of the shank, such as bin-
angle.

13. Black’s instrument formula
 Black’s formula describes :
 the dimensions of an instrument.
 the angulation of the instrument.

14. Hand - cutting instruments
(cut hard or soft tissues)
A- Excavators
Hatchet,hoes,spoons,
angle former
B- Chisels
Straight ,curved, bin –angle,
enamel hatchet
C- Others
Knives,files,carvers,gingival
marginal trimmer

15. Ordinary hatchet excavator:
 The cutting edge of the blade directed in the same
plane of the long axis of the handle and is bi-beveled.
 we use it primarily on anterior teeth to prepare
retantative areas and sharpening internal line angles
A- Excavators

16. Hoe excavators:
 has the primary cutting edge of the blade perpendicular
to the axis of the handle.
 we use it for: planning tooth preparation walls and
forming line angles.
used in class III and V for direct golden restorations.and
intended for use on enamel of posterior teeth.
A- Excavators

17. angle former:
• it is used for sharpening line angles and creating retentive
feauters in dentin in preparation for gold restorations .
• It also may be used in placing a bevel on enamel margins.
• It is mon-angled and has the primary cutting edge at an angle
(other than 90 degrees) to the blade.
• It may be described as a combination of a chisel and gingival
margin trimmer.
• It is available in pairs (right and left).
A- Excavators

18. Spoon excavators:
 they are used for removing caries and carving amalgam or
direct wax patterns.
The blades are slightly curved and the cutting edges are either
circular or clawlike.
 The circular edge is known as a discoid, whereas the clawlike
blade is termed a cleoid.
 The shanks may be bin-angled or triple-angled to facilitate
accessibility.
A- Excavators

19. Straight Chisel:
The straight chisel has a straight shank and blade, with the
bevel on only one side.
Its primary edge is perpendicular to the axis of the handle.
B- Chisels

20. The bin-angle and Wedelstaedt chisels:
 the primary cutting edges is in a plane perpendicular to the
axis of the handle.
 may have either a distal bevel or a mesial (reverse) bevel.
The blade with a distal bevel is designed to plane a wall that
faces the blade's inside surface.
B- Chisels

21. Enamel hatchet:
 it is similar in design to the ordinary hatchet except that the
blade is larger, heavier, and is beveled on only one side.
 It has its cutting edges in a plane that is parallel with the axis of
the handle. It is used for cutting enamel and comes as right or left
types for use on opposite sides of the preparation.
B- Chisels

22. Gingival margin trimmer:
 is designed to produce a proper bevel on gingival enamel margins
of proximoocclusal preparations.
 It is similar in design to the enamel hatchet, except the blade is
curved.
 the primary cutting edge is at an angle (other than perpendicular)
to the axis of the blade.
 It is made as right and left types
B- Chisels

23.  Other hand cutting instruments, such as the knife, file, and
discoid-cleoid instrument, are used for :
trimming restorative material rather than for cutting tooth
structure.
C- Other cutting instruments

24. 1- knives: known as finishing knives, amalgam knives,or gold
knives, are designed with a thin, knifelike blade that is made in
various sizes and shapes.
Knives are used for trimming excess restorative
material on the gingival, facial, or lingual margins of a
proximal restoration or trimming and contouring the
surface of a Class V restoration.
C- Other cutting instruments

25. File:
 They used to:
 trim excess restorative material.
 They are particularly useful at gingival margins.
Blades of files are very thin, and teeth on the cutting
surfaces are short.
C- Other cutting instruments