Hand instruments and instrumentation
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Transcript of Hand instruments and instrumentation
HAND HAND INSTRUMENTSINSTRUMENTS
Flow chart IntroductionIntroduction HistoryHistory MaterialsMaterials Properties of materials usedProperties of materials used NomenclatureNomenclature ClassificationClassification Instrument formulaInstrument formula Instrument designInstrument design Various hand instruments techniquesVarious hand instruments techniques Individual instrumentsIndividual instruments Maintenance of instrumentsMaintenance of instruments
• sharpening of instrumentssharpening of instruments• SterilizationSterilization
INTRODUCTIONINTRODUCTION
In order to perform intricate and In order to perform intricate and detailed procedures associated with detailed procedures associated with conservative dentistry ,the dentists must conservative dentistry ,the dentists must have a complete knowledge of the have a complete knowledge of the purpose and application of the many purpose and application of the many instruments required.instruments required.
Hand Instruments remain an Hand Instruments remain an essential part of the armamentarium for essential part of the armamentarium for quality restorative dentistry.quality restorative dentistry.
HISTORY
The best guide to the future is to The best guide to the future is to study about the paststudy about the past.
In 16th century the excision of carious material was done by using burning stick.
Earlier materials like bone, ivory were some of the materials used to manufacture the instruments.
Materials used in manufacturing the Materials used in manufacturing the instrumentsinstruments
Stainless steel Stainless steel Carbon - 6 to 10 %, Carbon - 6 to 10 %, chromium – 18%, chromium – 18%, iron – 81 to 81.4 %iron – 81 to 81.4 %
When When 12 to 30% of chromium12 to 30% of chromium is added to iron, the is added to iron, the alloy is called stainless steel.alloy is called stainless steel.
- It is extremely hard- It is extremely hard- Resistance to staining in these alloys is attributed Resistance to staining in these alloys is attributed
to the formation of a thin transparent oxide on to the formation of a thin transparent oxide on their surface.their surface.
DrawbackDrawback - Loses a sharp edge on repeated usage - Loses a sharp edge on repeated usage easily compared to carbon steel. easily compared to carbon steel.
Carbon steel :Carbon steel :-- these are iron carbon binary alloys that contain these are iron carbon binary alloys that contain
less than approximately less than approximately 2.1 % carbon2.1 % carbon..
- It is capable of hardened, softened, and tempered.- It is capable of hardened, softened, and tempered.- Its melting point is approximately 1500- 1600 C.- Its melting point is approximately 1500- 1600 C.- Maintains keen edge under use, hence used for Maintains keen edge under use, hence used for
making blade and cutting edge.making blade and cutting edge.DrawbackDrawback – corrodes when un protected. – corrodes when un protected.
CarbideCarbide – –
Carbon steel containing Carbon steel containing 0.8% carbon0.8% carbon..- Provide more durable cutting edge.Provide more durable cutting edge.- Hard and wear resistant.Hard and wear resistant.
Monel metalMonel metal Nickel - 67%,Copper - 28%,Iron - 5%Nickel - 67%,Copper - 28%,Iron - 5% It’s a It’s a natural alloynatural alloy It is markedly resistant to acid and superheated steamIt is markedly resistant to acid and superheated steam NichromeNichrome Nickel - 60 to 80%,Chromium - 12 to 20%,Iron - 0.2 to 6%Nickel - 60 to 80%,Chromium - 12 to 20%,Iron - 0.2 to 6% Can be subjected to high degrees of temperatureCan be subjected to high degrees of temperature Does not oxidize easily Drawback : does not maintain sharp edge Stellite Cobalt 65- 90%, chromium 10-35% High melting point Maintains cutting edge and resistant to action of acids. Cobalt imparts hardness, strength and rigidity to alloy
In order to gain maximal benefits Carbon steel and In order to gain maximal benefits Carbon steel and stainless steel must be submitted to hardening and stainless steel must be submitted to hardening and tempering heat treatmenttempering heat treatment
Hardening heat treatmentHardening heat treatment Tempering heat treatmentTempering heat treatment
hardens and makes it brittle. Steel is reheated for 1 hour athardens and makes it brittle. Steel is reheated for 1 hour at steel is heated to steel is heated to 1500 F(815 C)1500 F(815 C) 350 F 350 F (176 C)(176 C) and then in oxygen free environment and and then in oxygen free environment and quenched. It relieves strain and quenched. It relieves strain and
then quenched water. then quenched water. increases the toughness. increases the toughness.
NOMENCLATURENOMENCLATURE Described by Described by G.V. BlackG.V. Black
1. 1. OrderOrder – denotes the purpose of the – denotes the purpose of the instrument. instrument.
E.g. excavator, scalerE.g. excavator, scaler2. 2. SuborderSuborder – denotes position or manner of – denotes position or manner of
use. use. E.g. push ,pullE.g. push ,pull (variable and non-specific)(variable and non-specific)3. 3. ClassClass – describes form of the blade – describes form of the blade E .g. hatchet , chiselE .g. hatchet , chisel
4. 4. AngleAngle – denotes number of angle in – denotes number of angle in shank shank
Classification Classification (Sturdevant)(Sturdevant) HAND INSTRUMENTS
CUTTING NON-CUTTING
EXCAVATORS
ORDINARY HATCHET
HOE
CHISELS
ANGLE FORMER
SPOON EXCAVATOR
STRAIGHT
CURVED
BINANGLE
ENAMEL HATCHET
GINGIVAL MARGINAL TRIMMER
AMALGAM CONDENSER
MIRRORS
EXPLORERS
PROBES
OTHERS
KNIVES
FILES
SCALERS
CARVERS
Hand instrumentHand instrument::1.Cutting instruments1.Cutting instruments
Hatchets Hatchets Chisels Chisels Hoes Hoes Excavators Excavators 2.Condensing 2.Condensing
instrumentsinstruments -pluggers-pluggers3.Plastic 3.Plastic
instrumentsinstruments -spatulas-spatulas -carvers-carvers -burnishers-burnishers -packing -packing
instruments.instruments.
4.Finishing and 4.Finishing and
polishing polishing instrumentsinstruments
- orange wood stick- orange wood stick - polishing points - polishing points - finishing strips- finishing strips
5.Miscellaneous 5.Miscellaneous instrumentsinstruments
- mouth mirrors. - mouth mirrors. - explorers.- explorers. - scissors.- scissors. - pliers.- pliers.
INSTRUMENT FORMULAINSTRUMENT FORMULA 4 unit formula4 unit formula
1.1. Width of the blade or primary cutting edge in tenths Width of the blade or primary cutting edge in tenths of a mm.of a mm.
2.2. Primary cutting edge angle ,expressed as a percent Primary cutting edge angle ,expressed as a percent of 360 degrees.of 360 degrees.
3.3. Indicates blade length in mm.Indicates blade length in mm.4.4. Indicates blade angle relative to the long axis of the Indicates blade angle relative to the long axis of the
handle in clockwise direction.handle in clockwise direction.– 3 unit formula3 unit formula
1.1. Width of the blade or primary cutting edge in tenths Width of the blade or primary cutting edge in tenths of a mm.of a mm.
2.2. Indicates blade length in mm.Indicates blade length in mm.3.3. Indicates blade angle relative to the long axis of the Indicates blade angle relative to the long axis of the
handle in clockwise direction.handle in clockwise direction.
blade
Cutting edge
Handle or shaft
shank
INSTRUMENTSINSTRUMENTS
A)A) direct cuttingdirect cutting instrument-instrument- forces applied in forces applied in the same plane the same plane of blade and of blade and handle.handle.
B)B) Single planedSingle planed
C)C) Can be used in Can be used in both direct and both direct and lateral cutting. lateral cutting.
B) B) lateral cutting instrument-lateral cutting instrument- force applied at right angle to force applied at right angle to blade and handleblade and handle
Double planedDouble planedused only in lateral cuttingused only in lateral cutting
Thinner the cross sectionMore the force is concentratedon the working area
Main principle of cutting instrument is to concentrate forces on a very thin cross section of theinstrument at the cutting edge
2.2. ContranglingContrangling depends on length of the blade and angulation in shankdepends on length of the blade and angulation in shank..PurposePurpose---mainly to gain access.-mainly to gain access.
-instruments are designed such that -instruments are designed such that working point is working point is within 3mmwithin 3mm from the axis of handle.from the axis of handle.
-short blade and small blade angles require only binangle -short blade and small blade angles require only binangle contrangling.contrangling.
-longer blade and greater blade angle require triple angle -longer blade and greater blade angle require triple angle contrangling.contrangling.
Greater angles are used inGreater angles are used in – –-posterior teeth-posterior teeth-incisal portion of proximal cavities-incisal portion of proximal cavities inin
anteriorsanteriors..
For optimal anti rotationaldesign, the blade edge must be within 3mm fromthe axis of handle.All dental instruments need to satisfy thisprinciple of balance.
For optimal anti rotationaldesign, the blade edge must be within 3mm from the axis of handle.All dental instruments need to satisfy thisprinciple of balance
3.Right and left instrument:3.Right and left instrument: Direct cutting instrument held Direct cutting instrument held
with the cutting edge facing with the cutting edge facing down and pointing away from down and pointing away from the operator and the bevel is the operator and the bevel is on right side, it is right on right side, it is right instrument. if bevel is on the instrument. if bevel is on the left, left instrument.left, left instrument.
These are single planed These are single planed instruments. instruments.
Lateral cutting instrument Lateral cutting instrument are made right and left by are made right and left by having the curve or angle. having the curve or angle. these are always used in these are always used in scraping actions. scraping actions.
4.4.Single bevelled instrument:Single bevelled instrument: Single planed Single planed
Cutting edge at right angles to long axis of shaft.Cutting edge at right angles to long axis of shaft.
Bevelled on the side away from the shaft –distally Bevelled on the side away from the shaft –distally bevelled.bevelled.
Bevelled on the side towards the shaft- mesially Bevelled on the side towards the shaft- mesially bevelled.bevelled.
When the instrument have When the instrument have no angle or angle ofno angle or angle of 12 12 degree or lessdegree or less, it is used in push (direct cutting) and , it is used in push (direct cutting) and scraping motions.scraping motions.
If angle in shank If angle in shank exceeds 12 degreeexceeds 12 degree, , instrument is instrument is used in pullused in pull (distally bevelled) and (distally bevelled) and push (mesially bevelled) motions.push (mesially bevelled) motions.
5.5.BibevelledBibevelled instrumentinstrument:: Only hatchets and Only hatchets and
straight chisels can straight chisels can be bibevelledbe bibevelled..
Blade is equally Blade is equally bevelled on both bevelled on both sides.sides.
They They cut bycut by pushingpushing them in them in the direction of the the direction of the long axis of the long axis of the blade. blade.
6.6.Triple bevelled instrument:Triple bevelled instrument:
Bevelling the blade laterally, forms Bevelling the blade laterally, forms three distinct cutting edges.three distinct cutting edges.
Most modern single planed Most modern single planed instruments are triple bevelled.instruments are triple bevelled.
AdvantageAdvantage-additional cutting -additional cutting potential.potential.
7.Circumferentially bevelled 7.Circumferentially bevelled instrumentsinstruments
Usually occurs in Usually occurs in double planed double planed instruments instruments
Bevelled at all Bevelled at all peripheriesperipheries
8.Single ended and double ended 8.Single ended and double ended instrumentsinstruments
The most modern instruments are double The most modern instruments are double ended.ended.
Single planed instruments with no angle Single planed instruments with no angle in the shank have potential 5 cutting in the shank have potential 5 cutting movements. They are –movements. They are –
vertical,right ,left,push and pullvertical,right ,left,push and pull Mesially and distally bevelled single Mesially and distally bevelled single
planed instruments the 4 movements are planed instruments the 4 movements are vertical,right ,left ,push or pull.vertical,right ,left ,push or pull.
Hand instrument techniquesHand instrument techniques1.1. Modified pen graspModified pen grasp
- -permits the permits the greatest delicacy of greatest delicacy of touch.touch.
-palm of the hand -palm of the hand generally facing away generally facing away from the operator.from the operator.
-pad of the middle -pad of the middle finger placed near top finger placed near top of the instrument.of the instrument.
2. Inverted pen grasp-2. Inverted pen grasp- -The hand is rotated so -The hand is rotated so
that the palm faces that the palm faces more towards the more towards the operatoroperator
-Used for tooth -Used for tooth preparations utilizing preparations utilizing the lingual approach on the lingual approach on anterior teeth.anterior teeth.
3.Palm and thumb grasp3.Palm and thumb grasp - Has limited use- Has limited use - Used for preparing - Used for preparing
incisal retention for a incisal retention for a class III preparation class III preparation on a maxillary incisoron a maxillary incisor
4.Modified palm and thumb grasp4.Modified palm and thumb grasp
RestRest When the modified pen grasp and inverted When the modified pen grasp and inverted
pen grasp are used, rests are established by pen grasp are used, rests are established by placing the ring or ring and little finger on a placing the ring or ring and little finger on a tooth of the same arch or close to the tooth of the same arch or close to the operating siteoperating site
when palm and thumb grasp are used, rest when palm and thumb grasp are used, rest are created by placing the tip of thumb on are created by placing the tip of thumb on the tooth being operated or adjacent or area the tooth being operated or adjacent or area which is convenient. which is convenient.
Guards Guards Are hand instruments or other Are hand instruments or other items, such as interproximal wedges used to items, such as interproximal wedges used to protect soft tissue from contacting with protect soft tissue from contacting with sharp cutting or abrasive instruments.sharp cutting or abrasive instruments.
INDIVIDUAL INSTRUMENTSINDIVIDUAL INSTRUMENTS ExcavatorsExcavators
1.1. Hatchet excavatorsHatchet excavators• edge of the blade is edge of the blade is
parallel with handle parallel with handle • Single planed Single planed
bibevelled bibevelled instrumentinstrument
• Cut by push or Cut by push or scraping motionscraping motion
• Used for delicate Used for delicate cutting within cutting within preparations preparations especially in incisorsespecially in incisors
2.Hoe excavators2.Hoe excavators• Bevel run at right Bevel run at right
angle to the shaftangle to the shaft• TypesTypes-distally -distally
bevelled or mesially bevelled or mesially bevelledbevelled
• Use Use -cutting of -cutting of mesial and distal mesial and distal walls of premolars walls of premolars and molarsand molars
• Single planed ,4 Single planed ,4 cutting movements-cutting movements-vertical ,push or vertical ,push or pull, right and leftpull, right and left
3.Spoon excavators3.Spoon excavators• Made in pairs with Made in pairs with
one blade curved to one blade curved to right and other to leftright and other to left
• Curve of the blade Curve of the blade makes it lateral makes it lateral cutting instrumentcutting instrument
• Double planed Double planed instrument with right instrument with right or left cutting or left cutting movements onlymovements only
• Use-removal of Use-removal of carious dentincarious dentin
4.Discoid(disc like) excavators4.Discoid(disc like) excavators
• Blade circular in Blade circular in shapeshape
• Circular blade is Circular blade is placed at right placed at right angle to the shaftangle to the shaft
• Double planed Double planed instrument with instrument with right or left cutting right or left cutting movements onlymovements only
• Use-removal of Use-removal of carious dentincarious dentin
5. 5. Cleoid (claw like) excavatorCleoid (claw like) excavator
• Type of spoon Type of spoon excavator except excavator except the blade comes to the blade comes to a pointa point
• Use-carving Use-carving amalgam and amalgam and excavating deep excavating deep cariescaries
• Double planed Double planed instrument with instrument with only lateral cutting only lateral cutting movementsmovements
• CHISELSCHISELS
• Mainly intended for cutting enamel.Mainly intended for cutting enamel.• Used to smoothen cavity walls.Used to smoothen cavity walls.• Usually bevelled on one side only.Usually bevelled on one side only.• Used to sharpen cavity preparation.Used to sharpen cavity preparation.
4 types of Chisel4 types of Chisel
1.1. Straight chiselsStraight chisels– Straight blade in Straight blade in
line with the handle line with the handle and shankand shank
– Cutting edge on Cutting edge on one side onlyone side only
– Bevel of blade at Bevel of blade at right angle to the right angle to the shaftshaft
– Single planed with Single planed with 5 possible cutting 5 possible cutting movementsmovements
2.Monoangle chisel2.Monoangle chisel
Similar to straight Similar to straight chisels except that chisels except that blade is placed at blade is placed at an angle to the an angle to the shaft.shaft.
It may be mesially It may be mesially bevelled or distally bevelled or distally bevelled.bevelled.
Single planedSingle planed
3.Binangle chisel3.Binangle chisel
Blade is placed at a Blade is placed at a slight angle to slight angle to shaft.shaft.
Mesially or distally Mesially or distally bevelled.bevelled.
Use-to cleave or Use-to cleave or split undermined split undermined enamel.enamel.
Single planed.Single planed.
4.4.Triple-angle chiselTriple-angle chisel
Used to flatten Used to flatten pulpal floors.pulpal floors.
Mesially or distally Mesially or distally bevelled.bevelled.
Special forms of chiselsSpecial forms of chisels1.1. Enamel hatchet:Enamel hatchet:
• Shank has one or Shank has one or more angles or curves.more angles or curves.
• Blade is parallel with Blade is parallel with the shaft.the shaft.
• It is single plane It is single plane instrument.instrument.
• Design similar to Design similar to ordinary hatchet.ordinary hatchet.
• Blade is heavier, Blade is heavier, larger and beveled on larger and beveled on only one side.only one side.
• Use –for splitting or Use –for splitting or cleaving undermined cleaving undermined enamel in proximal enamel in proximal cavities. cavities.
2.2.Gingival Marginal TrimmerGingival Marginal Trimmer Similar in design to enamel hatchet Similar in design to enamel hatchet
except blade is curved.except blade is curved. Double ended, paired instrument Double ended, paired instrument
(mesial or distal).(mesial or distal). Primary cutting edge is at an angle to Primary cutting edge is at an angle to
axis of blade.axis of blade. when the second number iswhen the second number is 90 to 100 distal gingival margin.90 to 100 distal gingival margin. 85 to 75 mesial gingival margin.85 to 75 mesial gingival margin.
The 100 and 75 pairs are for inlay or The 100 and 75 pairs are for inlay or onlay preparations with steep gingival onlay preparations with steep gingival bevels.bevels.
90 and 85 pairs are for amalgam 90 and 85 pairs are for amalgam preparations with gingival enamel bevels preparations with gingival enamel bevels that decline slight gingivally.that decline slight gingivally.
Primarily lateral cutting instrument.Primarily lateral cutting instrument.
Used in pull and push motions to sharpen Used in pull and push motions to sharpen point and line angels.point and line angels.
Distal Gingival marginal trimmer
Mesial gingival marginal trimmer
GMT ENAMEL HATCHETGMT ENAMEL HATCHET
- 4 unit formula- 4 unit formula- Blade is curved - - Blade is curved - Bi planed Bi planed - Used to give - Used to give gingival cavosurface gingival cavosurface bevel, rounding of axio bevel, rounding of axio pulpal line angles. pulpal line angles.
- 3 unit formula- 3 unit formula- Not curved - Not curved - Monoplaned - Monoplaned - Used to break - Used to break enamel wall of enamel wall of proximal box, proximal box, smoothen gingival smoothen gingival seatseat
3.3.Angle FormerAngle Former
Are made by grinding the bevel at an Are made by grinding the bevel at an angle of 80 degree with the shaft, angle of 80 degree with the shaft, forming an acute angle with the long axis forming an acute angle with the long axis of the shaft.of the shaft.
Single planed instrument.Single planed instrument. Used to cut line and point angles.Used to cut line and point angles. They share three cutting potentials They share three cutting potentials
vertical, push and pull.vertical, push and pull.
4.4.Wedelstaedt Chisels.Wedelstaedt Chisels. Its like a straight chisel, with a slight Its like a straight chisel, with a slight
vertical curvature in the shank.vertical curvature in the shank. Bevelled on only one side of the shank.Bevelled on only one side of the shank. Single planed instruments with three Single planed instruments with three
cutting motions, vertical, right and left.cutting motions, vertical, right and left. Mesially bevelled used in push Mesially bevelled used in push
movement, distally bevelled in pull movement, distally bevelled in pull motions.motions.
USE-USE- For cleaving undermined enamel.For cleaving undermined enamel. For shaping walls.For shaping walls. Used primarily on anterior teeth.Used primarily on anterior teeth.
5.5.Off Set HatchetsOff Set Hatchets Rectangular hatchet except the Rectangular hatchet except the
hole blade is rotated forward or hole blade is rotated forward or backward around its long axis.backward around its long axis.
Single paned instrument.Single paned instrument.
They will be right or left They will be right or left instrument.instrument.
Useful to create and shape Useful to create and shape specific angulations for cavity specific angulations for cavity walls specially in areas of difficult walls specially in areas of difficult access.access.
6.6.Triangular Chisels.Triangular Chisels.
Blade is triangular in shape, Blade is triangular in shape, with base of the triangle away with base of the triangle away from the shaft.from the shaft.
It has a terminal cutting edge It has a terminal cutting edge like straight chisel.like straight chisel.
7.7.Hoe chiselHoe chisel:: Similar to hoe excavators, has Similar to hoe excavators, has
a sturdier blade.a sturdier blade.
NON CUTTING INSTRUMEMTS Similar in Similar in
appearance to appearance to cutting instruments cutting instruments except, blade is except, blade is replaced by nib or replaced by nib or point.point.
1.1. Amalgam carriersAmalgam carriers:: Types: Types:
a)regular a)regular b)largeb)large
Usually Usually Double ended.Double ended.
Available as Available as mini, regular, mini, regular, large, jumbo.large, jumbo.
2.2.Condensers:Condensers: Working ends or nibs are round with flat ends.Working ends or nibs are round with flat ends.
Shapes-round,triangular,rectangular or Shapes-round,triangular,rectangular or diamond.diamond.
Vertical condensationVertical condensation: amalgam condensed : amalgam condensed against preparation floor through vertical against preparation floor through vertical pressure.pressure.
Lateral condensationsLateral condensations: condensed against : condensed against vertical walls of preparation.vertical walls of preparation.
3.Carvers3.Carvers
1.1.Cleoid-discoid carversCleoid-discoid carvers::• Use:-occlusal carving of amalgam Use:-occlusal carving of amalgam
restoration.restoration.• - carving occlusal surfaces of posterior resin - carving occlusal surfaces of posterior resin
composite restoration.composite restoration.
2.2.Walls no.3 carversWalls no.3 carvers :-used for carving :-used for carving occlusal surfaces.occlusal surfaces.
-for shaping cusps and carving facial and -for shaping cusps and carving facial and lingual walls of large amalgam restorations.lingual walls of large amalgam restorations.
. . 3.3.Hollen back No.1/2 carverHollen back No.1/2 carver:: useful for occlusal,proximal,axial(facial useful for occlusal,proximal,axial(facial or lingual) surfaces. or lingual) surfaces.
4.inter proximal carvers4.inter proximal carvers:-:- specially valuable for carving proximal specially valuable for carving proximal
amalgam surfaces.amalgam surfaces.
5.No.14L carver:5.No.14L carver: (sickle shaped carver) (sickle shaped carver) Use Use - - interinter proximalproximal areasareas..- for carving convex facial and lingual - for carving convex facial and lingual
surfaces of large amalgam surfaces.surfaces of large amalgam surfaces.- To remove amalgam over hangs- To remove amalgam over hangs
Hollen back carver
Diamond or Frahms carver
Titanium carbide instruments
Wards carver
4.Burnishers4.Burnishers BurnisherBurnisher is defined as “to make shiny or lustrous, especially by is defined as “to make shiny or lustrous, especially by
rubbing; to polish”; and “to rub ( a material) with a tool rubbing; to polish”; and “to rub ( a material) with a tool for compacting or smoothening or for turning an edge”.for compacting or smoothening or for turning an edge”.
useuse-to shape metal matrix bands.-to shape metal matrix bands. -large burnishers are used to pinch off -large burnishers are used to pinch off
freshly condensed amalgam at margins. freshly condensed amalgam at margins. -PKT3 (P.K.Thomas No.3)burnisher useful in sculpting -PKT3 (P.K.Thomas No.3)burnisher useful in sculpting
occlusal anatomy in posterior resin composite.occlusal anatomy in posterior resin composite. -to bend cast gold near the margin.-to bend cast gold near the margin.
5.Plastic instruments5.Plastic instruments Originally they were Used with silicates and Originally they were Used with silicates and
acrylic resins . acrylic resins .
Now used to carry and shape tooth colored Now used to carry and shape tooth colored restorative materials .restorative materials .
It is a double ended instrument.It is a double ended instrument.
Available as hard plastic and metal.Available as hard plastic and metal.
use- to eliminate abrasion of metal by the quartz use- to eliminate abrasion of metal by the quartz in resin composite, which cause grayness.in resin composite, which cause grayness.
6.Cement spatulas6.Cement spatulas
Variety of instrument Variety of instrument require mixing on require mixing on glass slab, or paper glass slab, or paper pad.pad.
Larger spatulas used Larger spatulas used for mixing, luting for mixing, luting cements.cements.
Smaller spatulas used Smaller spatulas used for cavity liners and for cavity liners and resin luting cements. resin luting cements.
7.Mouth mirror7.Mouth mirror
Allows indirect visualization of Allows indirect visualization of obscure areas of the mouthobscure areas of the mouth
Allows the operator to Allows the operator to maintain body position that maintain body position that reduces health problems reduces health problems associated with poor posture.associated with poor posture.
Serves as retractor of soft Serves as retractor of soft tissue to aid in access and tissue to aid in access and visualization.visualization.
Front surface mirror- Front surface mirror- reflective surface of the reflective surface of the mirror is towards the surface mirror is towards the surface of glass.of glass.
Widely used sizes No.4 and Widely used sizes No.4 and No.5, for posterior region No.2 No.5, for posterior region No.2 is used. is used.
Normal mouth mirror reflects a secondary image Normal mouth mirror reflects a secondary image from the front of the glass in addition to main from the front of the glass in addition to main image from the silvered backing.image from the silvered backing.
This can be avoided by using front surface mirror This can be avoided by using front surface mirror where the reflective coating is deposited on the where the reflective coating is deposited on the front of the glass or the base, revealing fine detail front of the glass or the base, revealing fine detail more clearlymore clearly
Unfortunately, this coated surface gets weared Unfortunately, this coated surface gets weared easily, thus it does not last longereasily, thus it does not last longer
8.Explorers8.Explorers
It has 3 parts:It has 3 parts: - handle, shank and - handle, shank and
the exploring tip.the exploring tip. 4 Types: 4 Types: - straight explorer- straight explorer - right-angled - right-angled
explorerexplorer - arch explorer - arch explorer - interproximal - interproximal
explorer explorer
No.23 explorer
No.17explorer
9.Forceps 9.Forceps
Cotton forcepsCotton forceps Hemostats - helpful in Hemostats - helpful in
placing or removing items placing or removing items used to confine amalgam used to confine amalgam for condensation.for condensation.
Articulating paper forceps- Articulating paper forceps- to mark the contacts of to mark the contacts of teeth in opposing arches teeth in opposing arches during closure.during closure.
Maintainance of hand instrumentsMaintainance of hand instruments• Instruments with dull cutting edge cause:Instruments with dull cutting edge cause:
Prolong operating time Prolong operating time More painMore pain Less controllableLess controllable Reduce quality and precision in tooth preparation.Reduce quality and precision in tooth preparation.sharpening of hand instruments:sharpening of hand instruments:
types of sharpening equipementstypes of sharpening equipements::1.Stationary sharpening equipements1.Stationary sharpening equipements::
-most frequently used.-most frequently used. -also called oil stone.-also called oil stone. -available as coarse,medium or fine grit.-available as coarse,medium or fine grit. -shapes:flat,grooved,cylindric and tapered.-shapes:flat,grooved,cylindric and tapered.
Materials used for sharpening Materials used for sharpening instrumentsinstruments
Arkansas stoneArkansas stone:-(naturally occurring mineral):-(naturally occurring mineral) Preferred for fine sharpening.Preferred for fine sharpening.
Types-hard and soft.Types-hard and soft.Silicon carbideSilicon carbide:-commonly used for :-commonly used for
-grinding wheels.-grinding wheels. -sand papers.-sand papers. -sharpening stone. -sharpening stone. AluminumAluminum
oxideoxide -coarse or medium grit stones are speckled tan or -coarse or medium grit stones are speckled tan or brownish in color.brownish in color.-fine grit stones are usually white.-fine grit stones are usually white.DiamondDiamond:- hardest abrasive.:- hardest abrasive.-most effective.-most effective.-Only material routinely capable of sharpening carbide and -Only material routinely capable of sharpening carbide and
steel instruments. steel instruments.
2.2.Rx honing machineRx honing machine: it is a mechanical : it is a mechanical sharpener.sharpener.
• 3 3 Handpiece sharpeningHandpiece sharpening stonesstones:: -mounted silicon carbide.-mounted silicon carbide. -aluminum oxide. -aluminum oxide.
References Operative dentistry – modern theory & practice
Marzook, Simonton, gross (1st edition) Pichard’s manual of operative dentistry (8th edition)
Kidd, Smith & Watson Principles & practice of operative dentistry
(2ndedition) Gerald T . Charbeneau et al Studervant Fundamentals of operative dentistry.
A Contemporary approachSummit, Robbins, Schwartz
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