endodontic instrumen.ppt

5/26/2018 Endodontic Instrumen.ppt

1/18

Endodontic Instruments

Dr Shashit shetty


2/18

According to function Grossman

divided endodontic instruments into

1. Exploring instruments assist in locating andobtaining patency of the root canal. Eg endodonticexplorer, smooth broaches.

2. Debriding instruments assist in removal of pulpand debris from the root canal. Eg barbed broach.

3. Shaping instruments to shape the root canallaterally and apically so as to receive a root canalfilling. Eg files, reamers, etc.

4. Obturating instruments to cement and pack guttapercha into the root canal. Eg spreader, plugger,lenturospiral.

Nowadays an addition has been made. Access cavity

preparation instuments.


3/18

Shaping instruments were further

divided into 3 groups by Cohen

I. Group 1 hand use only. Reamers, files.II. Group 2 instruments having latch type

attachment. Peaso reamer, glades glidden

drill.

III. Group 3 instruments of group 1 used withhandpiece. Giromatic handpiece.


4/18

Standardization of endodontic

instruments.

1. Instruments to be numbered from 10 to 100.Numbers to advance by 5 units till 60 and 10 units till100.

2. Each number will be representative of the diameter

of the instrument in hundredth of a millimeter at thetip. For eg no 10 is 10/100 or 0.1mm at tip. No 25 is25/100 or 0.25mm at the tip.

3. The working blade shall begin at the tip designated as

D0 and terminate 16mm up the shaft. The diameterof the instrument at D16 will be 32/100 or 0.32mmgreater than that of D0, ie a constant increase of0.02mm taper every mm regardless of the size.


5/18


6/18

Other specifications added later on

were

A. Tip angle of 75 15.

B. 100,110,120,130,140,150, 06, 08, & 10 size of instrumentswere added.

C. Color coding was introduced.

15white 20yellow 25red 30blue 35green 40black and so on.D. Available in lengths of 21mm, 25mm, 28mm and 31mm.


7/18

Physical characteristics of reamers

and files.Available as

Carbon steel Stainless steel3. Nickel titanium

Stainless steel wire was ground into either 4 sided {square} or3 sided {triangular} blanks. They were then twisted to formflutes extending 16mm from the tip of the cutting blade.

Number of flutes twisted determines whether the instrumentis a reamer or file.

Reamer flutes are spaced. ie less number of flutes.File flutes are closer. ie more number of flutes.

Blanks used for smaller instruments where instrumentfracture is possible.

Blanks used where cutting efficiency is to be increased.


8/18

K-flex : Recently {rhomboidal} shaped blanks havebeen twisted to produce a file called as K-flex.Combination of square and triangular blanks.

Alternating high and low flutes. Increases flexibility andcutting efficiency.

Hedstroem files : H-files, wire is machine cut toproduce spiral flutes resembling cones or screw.Greater cutting efficiency than K-file, but is fragile andbreaks easily.

Unifiles : machined from wire to produce flutes in adouble helix design.


9/18

Functional characteristics of reamers

and files.

A. Reamer rotating, pushing motion, limited to aquarter turn , engaging the dentin and pulling motion

till the working length is achieved.

B. File same size file is inserted to the workinglength, lateral pressure applied and withdrawn with a

pulling motion. procedure repeated all around thecanal walls. Known as circumferential filling.

Next size reamer is taken and the entire

procedure is repeated.


10/18

Rotary endodontic instruments

These are engine driven. With the introductionof nickel-titanium files, rotary instrumentsbecame popular. Less time consuming and

better canal shape were the advantages. The advantages of ni-ti files were low elastic

modulus and good flexibility.

The disadvantages were, it is expensive anddificult to manufacture. Example : giromatic , racer.


11/18

Recent advances.

1. Profile series and Profile G.T.

2. Protaper series.

3. Light speed.4. Quantec

5. POW-R

6. Hero 6427. Sonic and Ultrasonic.


12/18

Photographs of endodontic

instruments


13/18

Shaping instruments


14/18

Gates Glidden drill Peaso reamer


15/18

Obturating instruments


16/18

Paper points Gutta percha


17/18


18/18

Thank you

endodontic instrumen.ppt

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