This document discusses dental instruments including their basic parts, classification, and care. It describes the working end, handle, and shank of instruments and how they are designed for different functions. Instruments are classified as cutting or non-cutting, by the number of working ends, manufacturer's number, and Black's formula. Examples of cutting instruments include chisels, hatchets, and gingival margin trimmers. Non-cutting instruments include mirrors, explorers, burnishers, and carriers. Proper cleaning, maintenance, and sterilization of instruments is covered, as well as tray systems for organizing instruments.

1. BASIC CHAIRSIDE
INSTRUMENTS
& TRAY SYSTEMS
Parts of hand instruments
Classification
Cutting/non-cutting
Instrument care, maintenance and sterilization
Tray systems

2. BASIC STRUCTURAL PARTS OF HAND
INSTRUMENTS

3. WORKING END
• Performs specific function of the instrument
• May be a:
• Point
• Sharp and used to explore, detect and reflect materials
• Blade
• Flat or curved and have rounded or cutting edge
• Cutting edge is formed by a bevel (slanted edge or side)
• Could be bi-beveled (both sides of he blade
• Nib
• Blunt end of an instrument that is serrated or smooth
• Beaks
• Smooth, serrated, grooved
• Rounded ends
• Different sizes and shapes and are used to smooth

4. THE HANDLE
• AKA: Shaft
• Where the instrument is held by the operator
• May be serrated or smooth
• Usually hexagonal (six-sided), for better grip
• Some handles are ergonomically designed
• Larger and designed with finger rests and grooves
• Other handles are covered with soft, rubber-like material that makes the instruments easier to
hold and grip
• Sterilizable and durable
• Some are designed with cone socket handles
• Allow the working ends to be replaced
• Mirrors
• Probes

5. THE SHANK
• Connects the handle to the working end
• Narrows or tapers from the handle to the working end
• May be angled to reach particular areas of the mouth
• Usually, if the instrument is used in the posterior part of the mouth, there
are more angles
• Shanks are formed in the following ways:
• Straight (no angles)
• Curved (slightly bent)
• Monoangle (one angle)
• Binangle (two angles)
• Triple angle (three angles)

6. BASIC CLASSIFICATION OF DENTAL
INSTRUMENTS

7. NUMBER OF WORKING ENDS
• The number of working ends on an instrument falls into two
categories:
• Single-ended
• One working end with long handle
• Double-ended
• Two working ends in the following combinations
• Two ends have similar functions, but one end is larger than the other (amalgam condenser)
• Two ends are paired left and right for preparing the right or left side of the cavity
preparation (gingival margin trimmer)
• Two ends have a combined function in which the ends are used for the same procedure but
each end has a different use (plastic filling instrument)

8. INSTRUMENTS CLASSIFIED BY FUNCTION
• Operative hand instruments are categorized
as cutting and non-cutting
• Other instruments are classified according to a
specialty, use with a specific material, or a
procedure

9. MANUFACTURER’S NUMBER
• Found on the handle of the instrument
• Used when ordering the instrument
• Indicates the instruments placement in a set
of instruments
• Some are named or classified by the name of
the individual who designed the instrument

10. BLACK’S FORMULA
• Developed by G.V. Black to standardize the exact size and
angulation of an instrument
• Minimizes discrepancies in the production of instruments from one
manufacturer to another and simplifies ordering
• Black’s formula for hand-cutting instruments includes the size of
the black and the angle at which its positioned to the handle.
• Some instruments (chisels, hatchets, hoes) have three numbers,
while others (angle formers, GMT’s) have four

11. BLACK’S THREE-NUMBER FORMULA
1. indicates width of the blade in tenths of millimeters
20 indicates a width of 2mm
2. indicates length of blade in millimeters
8 indicates a length of 8mm
3. Indicates angle of blade from long axis of shaft
12 indicates a blade angle of 12 degrees

12. BLACKS 4-NUMBER CLASSIFICATION
• 1- indicates width of the blade in tenths of millimeters
• 20 indicates a width of 2mm
• 2- indicates angle of cutting edge of blade in relation to the handle
• 95 indicates a cutting edge angle of 95 degrees
• 3- indicates length of blade in millimeters
• 8 indicates a length of 8mm
• 4- Indicates angle of blade from long axis of shaft
• 12 indicates a blade angle of 12 degrees
• Examples of 4-number instruments:
• Angle former, Mesial gingival margin trimmer, Distal gingival margin trimmer

13. Cutting Instruments Noncutting Instruments
Angle Formers Mouth mirror
Chisel Explorer
Excavator Cotton pliers
Gingival Margin Trimmer Burnishers
Hatchets Carriers
Hoes Carvers
Composite instruments
Condensers
Files
Plastic filling instruments

14. CUTTING INSTRUMENTS

15. CHISEL

16. ALL CHISELS
•To shape and plane (make surface flat
or level) enamel and dentin walls of the
cavity preparation
•Used with a PUSH motion
•3 types used…

17. CHISEL-STRAIGHT, WEDELSTAEDT, BI-ANGLE

18. STRAIGHT CHISEL
• To shape and plane enamel and dentin
walls of the cavity preparation
• Used with a PUSH motion
• Straight blade
• No angle
• Single-bevel cutting edge
• Single or double ended
• Used on class III or IV cavity preparations
• Used with a mallet to remove fixed
prosthesis

19. WEDELSTAEDT CHISEL
• To shape and plane enamel and dentin
walls of the cavity preparation
• Used with a PUSH motion
• Curved blade
• Single-bevel cutting edge
• Single or double ended
• Class III and IV cavity preparations
• 3-number instrument

20. BINANGLE CHISEL
• To shape and plane enamel and
dentin walls of the cavity preparation
• Used in a PUSH motion
• Two angles in the shank
• Single or doubled ended
• Class II cavity preparations
• 3-numbered instrument

21. HATCHET

22. ENAMEL HATCHET
• To clean and smooth walls in cavity preparation
• To remove enamel not supported by dentin
• Used with a PUSH motion
• Downward motion to refine the cavity walls and
obtain retention in the prep
• Cutting edge on same plane as handle
• Single or double ended
• Paired left and right
• 3-numbered instrument

23. HOE

24. ENAMEL HOE
•To clean and smooth floor and
walls in cavity preparation
•Used with a PULLING motion
•Cutting edge or blade nearly
perpendicular to handled
•3-numbered instrument
• 10-4-8

25. GINGIVAL MARGIN TRIMMER (GMT)
(B) DISTAL, (D) MESIAL

26. GINGIVAL MARGIN TRIMMER
• To bevel gingival margin walls of mesial and distal
retention areas
• Mesial- to place bevels on mesial cervical margin of
prep
• Distal- to place bevels on distal cervical margins of
prep
• Curved blade (unlike hatchet which is flat)
• Double ended(one curves to the right, other to left)
• Placed on the tray in pairs
• 4 number instrument
• M: 13-80-8-14
• D: 13-95-8-14

27. ANGLE FORMER

28. ANGLE FORMER
• To form and define point angles and
sharpen line angles
• Downward pushing motion
• Cutting edge at an angle
• Double ended
• Can be used on right or left surfaces of
prep
• 4-numbered instrument
• 12-80-5-8

29. EXCAVATORS

30. SPOON EXCAVATORS
(1)Large- Curved
blade
(2)Small- Round
blade

31. SPOON EXCAVATOR
• To remove carious material and
debris from teeth
• Secondary functions:
• Remove temporary crowns
• Remove excess temporary cement
• Remove permanent crown during try-in
• Tucking rubber dam material
• Packing gingival retraction cord
• Concave design, spoon shaped with
cutting edge
• Single or double ended

32. NON-CUTTING INSTRUMENTS

33. NONCUTTING INSTRUMENTS
• Include basic examination instruments and instruments used to
insert and finish amalgam and composite restorative materials.
• Examples include:
• Basic exam set up
• Plastic instruments
• Amalgam carriers
• Condensers
• Carvers
• Burnisher
• Files
• Finishing knives

34. BASIC EXAMINATION INSTRUMENTS
• All procedures begin with the operator examining
the teeth, so the mouth mirror, explorer and cotton
pliers are the first three instruments on the tray set
up
• The periodontal probe is optional (in some offices)

35. NONCUTTING INSTRUMENTS
• Basic examination
instruments
• Mouth mirrors
• Explorers
• Cotton pliers
• Periodontal probes

36. NONCUTTING INSTRUMENTS
• Plastic filling instruments (A)
• Placing and condensing restorative materials
• Woodson (B)
• Place and condense restorative materials
• Composite instrument (C)
• Placing, condensing, carving, contouring, and
burnishing
• These instruments are used after the cavity has been
prepped.
• It is important for the dental assistant to learn these
instruments and the sequence in which they are used.
• The instruments are used for placing bases and liners,
placing amalgam and composites, and contouring and
smoothing final restoration.

37. NONCUTTING INSTRUMENTS
•Amalgam carrier
•Carry and dispense amalgam
•Amalgam condenser/plugger
•Pack amalgam into cavity prep

38. NONCUTTING INSTRUMENTS
• Carver
• Remove excess restorative material
• Carve wax inlays and onlays

39. NONCUTTING INSTRUMENTS
• Burnishers
• Smooth restorations
• Shape matrix bands

40. NONCUTTING INSTRUMENTS
•Files
•Trim excess filling material,
smooth margins of the
restorations
•Finishing knife
•Trim excess filling material

41. MISCELLANEOUS INSTRUMENTS

42. NONCUTTING INSTRUMENTS
• Spatulas
• Cement
• Restorative procedures
• Plastic
• Composite resin materials
• Laboratory
• Impression materials and plaster

43. MISCELLANEOUS INSTRUMENTS
• Articulating forceps
• Hold articulating paper
• Colored paper used to check the patient’s occlusion after the filling material has
been placed
• Sometimes locking cotton pliers are used in place of articulating paper holder
• Scissors
• Crown and collar (bridge)
• Short blades
• Straight or curved
• Used to trim matrix bands
• Cut retraction cord

45. INSTRUMENT CARE, MAINTENANCE, AND
STERILIZATION
• Cleaned as soon as possible
• When this cannot be done, they should be placed in a presoak solution to prevent blood and
debris from drying on the instruments
• Place in ultrasonic cleaner
• Hinged instruments should be open
• Rinse and dry thoroughly after ultrasonic
• After sterilizing, dry completely before storing
• When bags are not dry, they become a source of bacterial contamination and they also tear
more easily
• Examine all instruments carefully, checking for
• Corrosion, stains, broken tips, sharpness, hinges

46. TRAY SYSTEMS

47. PRESET TRAY SYSTEM
• Most commonly used
• Efficient means of transporting instruments to tx room
• Instruments are placed in order of use on the tray
• The tray is covered and carried to trx room
• Different trays to choose from
• Metal, plastic, tubs, cassettes
• Could be color coded

48. POSITIONING ON TRAY
• Every operator has their own preference, but some basic
considerations are:
• Clear plastic tray barriers may be placed
• Instruments are placed in order of use, beginning on the left and moving to
the right
• The basic tray setup (mouth mirror, explorer, and cotton pliers) are placed
first
• Instruments should be groupd according to function
• Cotton supplies are usually arranged on top
• Scissors, hemostats, or other hinged instruments are placed to the far right
• Return instruments to their original position after receiving from operator
• Keep instruments clean and free of debris before returning to the tray (2x2)

49. CASSETTE INSTRUMENTS

50. COLOR CODING SYSTEMS
Method for easily identifying instruments and trays
• Color could indicate the following:
• Procedure
• Such as amalgam or composite
• Treatment rooms
• Additional sets of instruments
• There may be four composite setups, each marked for the procedure with one color, and then a
second color for the set
• Individual operators
• Different operators use different instruments
• Sequence
• Instruments can be color coded diagonally to indicate the sequence of use
• Any combination of these