Instrumentation Of Endodontics Question And Answers

Instrumentation Of Endodontics Important Notes

• Classification of instruments
  • Grossman’s classification
    • Exploring instruments – smooth broaches, endodontic explorer
    • Debridement – barbed broaches
    • Shaping instruments – reamers and files
    • Obturating instruments – pluggers, spreaders, lentulospirals
  • ISO grouping of instruments
    • Group 1 – hand use only
    • Group 2 – made to be attached to a handpiece
    • Group 3
      • Engine given latch type
      • Rotary canal instruments
    • Group 4 – root canal points
• Standardization of instruments
  • By Ingle le Vine
    • Numbering from 10 – 100
      • Advance by 5 up to 60
      • Advance by 10 up to 100
    • Diameter
      • D at tip – 1/10 of a mm
      • Ex. For instrument No.25 D1 = 0.25mm
      • D2 at the end of shaft
    • Length of working portion
      • 16mm from D1 to D2
    • Taper of 0.02 mm per mm
    • Angle of the tip 75 ± 15 degrees
    • Color coding
• H files
  • Made from a round blank to produce spiral flutes
  • They show higher cutting efficiency but is more prone to fracture
  • The angle between cutting edge and the long axis of the instrumentis about 60-65°
  • They are designed primarily for a linear filling motion
  • Due to positive rake angle they cut in one direction only

Endodontic Instruments

Endodontic Instruments Names

• K flex files
  • Cross section is rhombus or diamond shaped
  • They have better cutting ability and flexibility
  • The instrument is fabricated of V-4 steel
• Unifiles
  • Mc-Spadden modified the traditional H files
  • The blade present a S shape or double helix design
  • It has two continuous cutting edges
  • It can be used for cutting in both filling and reaming action
  • They are less subject to fracture
  • They are stiff in coronal and middle thirds but bends in apical 1/3rd
• Nickel – titanium files
  • Composition
    • Nickel – 54%
    • Titanium – 44%
    • Cobalt – 0.2%
    • Boran – added to improve surface hardness
  • At high temperature, it exists a body centered cubic lattice referred to as autestentic phase – a stronger phase
  • On cooling, this phase transfers to close packed hexagonal, weak phase known as martensitic phase
  • Two unique features of it are: shapre memory and super elasticity
  • The main disadvantage of it is its cutting efficiency is only 60%
• Flexogates
  • Derivative of Gates Glidden drills
  • Used to enlarge the apical region of the canal
  • Less likely to cause apical transporation
  • Less fracture resistant
  • Non cutting guiding tip
• Giromatic and Racer handpiece
  • Giromatic
    • It is commonly used reciprocating handpiece
    • It accepts only latch-type instrument
    • In this type the quarter turn motion is delivered 300 times per minute
    • It uses a barder broach or reamer through 90° reciprocating arc at a speed of 1000 cycles/min
  • Racer handpiece
    • It uses a standard file and oscillates the file in root canal
    • These instruments can be used for opening root canals but should not be used for root canal preparation
• Peaso reamer
  • They are more often used in preparing coronal portion of the root canal for past and core
  • Instrument fractures always near the shank
• Ultrasonic and sonic instruments
  • Used for cleaning and shaping of root canals
  • Ultrasonic instruments contains a magnetostrictive hand piece which hold a K file or diamond file
  • It is operated at 2000 – 25000/section
  • It uses sodium hypochlorite as irrigant
  • Sonic instruments operate at 1500 – 6500 cycles/min
  • It uses water as irrigant
• Colour coding

• Lentulospirals
  • They are used for placement of sealer, cement and calcium hydroxide
  • It must be operated clockwise in the handpiece and started or stopped outside the root canal
  • If started in the canal it may cut into the wall of the root canal and break

Endodontic Instruments Names

Read And Learn More: Endodontics Question and Answers

• Modifications of H file
  • Safety hed stroem
  • Hyflex file
  • Unifiles
  • S file
• Differences between reamer and file

Endodontic Instruments

• Gates Glidden drill
  • Uses
    • To remove lingual shoulder during access cavity preparation
    • To enlarge root canal orifices
    • For shaping cervical third of root canal in step back preparation

Instrumentation of Endodontics Long Essays

Question 1. Classify Endodontic Instruments. Describe standardization and sterilization of them.
Answer.

Grossman’s Classification:

• Exploring Instruments – Smooth broach
• Extripating Instruments – Barked broach
• Cleaning and Shaping Instrument – Files and Reamers
• Obturating Instruments – Pluggers and Spreaders

ISO And FDI Classification

• Group 1 – Hand operated Instruments
• Group 2 – Engine driven Instruments
  • Parts
  • Cutting head
  • Latch type of attachment
• Group 3 – Fabricated from single piece of metal Ex. Gates Glidden drill
• Group 4 – Usually materials Ex. GP points, paper points

Standardization: By Ingle le Vine

• Numbering from 10-100
  • Advance by 5 up to 60
  • Advance by 10 up to 100
• Diameter
  • D at tip – 1/10 of a mm
  • Ex. For instrument No.25 D1 = 0.25mm
  • D2 at the end of shaft
• Length of working portion
  • 16mm from D1 to D2
• Taper of 0.02 mm per mm
• Angle of the tip 75 ± 15 degrees
• Color coding

Endodontic Instruments

Sterilization:

Instrumentation of Endodontics Short Essays

Question 1. Endosonic Instruments.
Answer.

Introduced by Richman

Activation:

Endosonic Instruments Advantages

• Cleans the canal
• Enhances the action of NaOCl

Endosonic Instruments Types:

• Magnetostrictive
• Piezoelectric

Endosonic Instruments Mechanism:

• Navigation
• Acoustic streaming

Endodontic Instruments Names

Endosonic Instruments Uses:

• Access enhancement
• Orifice location
• Irrigation
• Sealer placement
• Guttapercha obturation
• MTA placement
• Endodontic retreatment.

Question 2. Obturating Instruments.
Answer.

• Obturating Instruments Spreaders:
  • Use: For lateral compaction
  • Material used: Stainless steel/Nickel titanium
  • Types:
    • Hand – Do not have standardized size and shape
    • Finger – Standardized and color coded to match size of GP points
• Obturating Instruments Pluggers:
  • Use: For vertical compaction, Forsectional method
  • Material use to pack: Calcium hydroxide/MTA

• Lentulospiral:

Question 3. Broaches.
Answer.

Broaches Types:

• Smooth broaches
• Barbed broaches

Broaches Broaches:

• Short handles instruments
• Made from round steel wires

Broaches Uses:

• Extripation of pulp tissues
• Removal of dressing
• Loosen necrotic debris
• Pathfinder [smooth broach]

Broaches Method Of Use:

Broaches Precaution:

• Should not be forced apically into canal

Question 4. H-files.
Answer.

H-files Manufacture:

• Round steel wire, machined to produce spiral flutes

H-file advantage:

• Higher cutting efficiency
• Push debris coronally

H-files Manner Of Use:

• Pull motion, cut dentin when the instrument is withdrawn

H-files Features:

• Positive Rake angle
• Distance between the flutes

H-files Disadvantages:

• Aggressive
• Lack flexibility
• Tend to fracture

H-files Use:

• For flaring coronal half of preparation
• To machnie straight canals

H-files Modifications:

• Unifiles
• Helifile
• S-file

Question 5. NiTi Files.
Answer.

NiTi Files

Known as Nitinol [NiTi Navol Ordinance Laboratory]

NiTi Files Types And Composition:

• 55 NiTinol [55% Ni, 45% Ti]
• 60 NiTinol [60% Ni, 40% Ti]

NiTi Files Advantages:

• Shape memory
• Super elasticity
• Softer
• Corrosion resistance
• Resiliency is good

NiTi Files Disadvantage:

• Poor cutting efficiency
• Do not show signs of fatigue
• Poor resistance to fracture

Instrumentation of Endodontics Short Answers

Question 1. Lentulospirals.
Answer.

Lentulospirals

• It is a obturating instrument
• Have latch type attachment

Lentulospirals Used:

• To coat the walls of root canal for sealer

Lentulospirals Significance:

• By sealing the canal walls, space between canal wall and material is avoided

Instrument used along with it: Giromatichand piece.

Question 2. Peaso – Reamer.
Answer.

Peaso – Reamer

• It is latch type rotatory instruments
• Have cutting sides
• Made up of stainless steel

Peaso – Reamer Used For:

• For parallel post preparation
• To remove guttapercha from canal

Peaso – Reamer Precaution:

• It do not follow canal curvature
• It is not flexible
• Should be used with low speed to prevent over instrumentation and perforation

Peaso – Reamer Sizes:

Question 3. Gates glidden Drill.
Answer.

Gates glidden Drill Description:

• Head – flame shaped with safe tip
• Culting end – Resembles American football
• Shank – long, elliptical shaped

Gates glidden Drill Used Along With:

• Latch attachment, slow speed handpiece

Gates glidden Drill Uses:

• Enlarging orifice in coronal 3rd of tooth
• To prepare post space
• To remove guttapercha/instrument

Gates glidden Drill Sizes:

Question 4. Files and Reamer
Or
Cross section of files and reamers.
Answer.

Files and Reamer

• These are cleaning and shaping instrument
• Difference

Question 5. Sterlization of instruments.
Answer.

Sterlization of instruments

Instrumentation Of Endodontics Viva Voce

• Broaches break easily
• Broaches should not be inserted unless the root canal is enlarged to a size of 20 or 25 reamer or file
• File contains more number of flutes and is four sided instrument
• Giromatic and Racer are contra angled engine driven instruments
• The instrument should be used with a 1/4 – 1/2 turn and withdrawn with a pull stroke
• Gates Glidden drill and Peaso reamer are power driven instruments
• Over instrumentation causes forcing of debris into periapocal area
• Instrumentation short of apex causes ledging of canal
• Instrumentation with large instruments causes enlarging of canal
• Reamers are used with pushing-rotating motion
• Files are used with rasping or pulling motion
• H file is used to finish the instrumentation of the coronal third of the root canal
• Endodontic explorer are most commonly used diagnostic and exploring instruments for idenfication of canal orifices