instruments

1. cutting

2. condensing

3. plastic

4. finishing and polishing

5. isolation

operative instruments

hand

1. hatchets

2. chisel

3. hoes

4. excavator

5. gmt

6. angle former

7. cleoid discoid

rotary

1. burs

2. stones

3. discs

cutting instruments (hand and rotary)

pluggers - hand and mechanical

condensing instruments

1. carvers

2. spatula

3. burnishers

plastic instruments

rotary

1. finishing brushes

2. mounted brush

3. rubber cups

4. impregnated wheels and discs

hand

1. finishing strips

2. orangewood sticks

3. polishing points

finishing and polishing instruments

1. rubber dam frame

2. clamp

3. forceps

4. punch

5. saliva ejector

6. evacuating tips

7. cotton roll holder

isolation instruments

1. amalgam condensers

2. mirrors

3. explorer

4. probes

non - cutting instruments

blade/nib

point or head. functional end

shank

connects the shaft and the blade or nib

handle/shaft

area where it is grasped

north america

• Small in diameter (5.5mm) and light

• Eight sided and knurled

europe

• Larger in diameter and tapered

A. Straight – Shank having no angle

B. Mon-angle – shank having one angle

C. Bin-angle (Mangle) – Shank having two angles

D. Triple-angle - Shank having three angles

shank angles explain

nib

the working end of a non-cutting instrument

blade

the working end of a cutting instrument

operative cutting instrument formula

these are placed on the handle using a code of 3 or 4 numbers separated by dashes or spaces

1. first - width of the blade or primary cutting edge in tenths of a millimeter (0.1mm)

2. second - primary cutting edge angle ; measured from a line parallel to the long axis of the instrument handle in clockwise centigrade (angle is expressed in percent of 360 degree)

3. third (2nd number of a 3 number code) - blade length in millimeter

4. fourth (3rd number of a 3 number code) - the blade angle ; relative to the long axis of the handle in clockwise centigrade

explain operative cutting instrument formula

single bevel

• excavator, gingival margin trimmers, enamel hatchet

• used with a scraping or lateral cutting action

• made in pairs (left and right)

examples?

bibeveled

If two additional cutting edges extend from primary cutting edges, then the instrument with secondary cutting edge is called bibeveled instruments

triple-beveled

If three additional cutting edges extend from the primary cutting edge, then the instrument is called triple-beveled instrument

pulling

Here, instrument is moved towards operator’s hand.

scraping

Here, instrument is move side-to-side or back and forth on the tooth surface.

pushing

Here, instruments is moved away from operator’s hand.

cutting

Here, instrument is used parallel to the long axis of handle.

1. chisel

• chisel

• hoe

• angle former

• cleoid/discoid

2. hatchet

• hatchet

• gmt

• spoon excavator

2 instrument families and what are they composed of

chisel

are used for cleaving, planing and lateral scraping. In other words, they are used to split tooth enamel, to smooth preparation walls and to sharpen the preparations. Chisels are used with a push motion

straight chisel

• cutting edge makes a 90° angle to the plane of the instrument

• used for gingival restoration of the anterior teeth

• perpendicular to long axis of handle

angled chisel

• primary cutting edge is in a plane perpendicular to the long axis of the shaft and may have either a mesial or distal bevel

• used with a push or pull motion for anterior proximal restorations

hoe

• cutting edge of the blade perpendicular to the axis of the handle

• to smooth and shape the floorand form line angles in Class III and V preparation

• pulling motion

1. monoangle hoe

2. biangle hoe

2 types hoe

angle former

• primarily for defining line angles and creating retentive features in dentin

• combination of a gingival trimmer and chisel

• also bevel

discoid

circular edge

cleoid

claw-like edge

spoon excavator

• a modified hatchet

• removing caries and carving amalgam or direct wax patterns

enamel hatchet

• blade is larger and heavier than an ordinary hatchet, beveled on only one side

• used for cutting enamel

GMT

• designed to produce proper bevel on the gingival enamel margins

• rounding or beveling of the axiopulpal line angle

1. stationary sharpening stones

2. mechanical sharpeners

types of sharpening hand instruments

Stationary Sharpening Stones (Oilstones)

• block or stick of abrasive material

• coarse, medium or fine grit – only the fine grit is suitable for sharpening dental instrument.

arkansas stone

• Naturally occurring mineral containing microcrystalline quartz

• Preferred material for fine sharpening stones

• Semi-translucent, white or gray

1. arkansas stone

2. silicone carbide

3. aluminum oxide

types of materials in stationary sharpening stones

silicone carbide

• Widely used as an industrial abrasive.

• Commonly used material for grinding wheels and sandpapers

• Dark color, black or greenish black

aluminum oxide

• Coarse or medium grit -Speckled tan or brownish

• Fine grit – white (superior in quality)

• Water or light oil can be used as lubricant

carbon steel and stainless steel

hand cutting instruments are manufactured from two main materials:

sterilization

implies the complete destruction of all microbial life including spores and resistant viruses

Dry Heat

Glass Bead

Ultraviolet light

Cold sterilization

Autoclaving (steam under pressure)

Dental Instrument are sterilized by the ff:

carbide

= operates most efficiently at high speed

= has the ability to retain its sharp edge over repeated usage

1⁄4 , 1⁄2 , 2, 4, 6 – 12

round bur

331⁄4,331⁄2, 34,35,37-40

inverted cone bur

55, 56, 57,58 – 61

Cylindrical plain (non-dentate) fissure

556, 557, 558,559, 560 – 563

Cylindrical crosscut fissure (dentate)

168, to 173

Tapered plain fissure

699, 700, 701, 702, 703

Tapered crosscut fissure

Light Amplification by Stimulated Emission of Radiation

device that produces beams of coherent very high intensity light

• Neodymium: yttrium-aluminum-garnet (Nd: YAG)

• Erbium: yttrium-aluminum-garnet (Er: YAG)

• Carbon Dioxide (CO2)

• Argon,Helium-neon

• Excimers

Types of Laser

1950

the first air-abrasive cutting was tested