7602224 Endodontic Instrument

8/11/2019 7602224 Endodontic Instrument

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[2008]

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TOSHIBA

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ENDODONTIC INSTRUMENTSDR.SHAWFE AR ! OD" IIUM


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Manual preparation instruments

1. REAMER

2. K-FILE3. FLEXOREAMER 4. FLEXOFILE5. HE !"ROEM FILE#. $i"i

A.REAMER

Reamer% esi&n ' !tru(ture

A reamer is manufactured from a triangular or square steel wire that is twisted to givethe typical shape of a reamer. The angle between the long-axis and the cutting blade issmall, which is why preparation by reamer is effective only in rotating motion.

The tip of the instrument is cutting which makes a reamer suitable for the preparation of straight canals only without the risk of ledging.

Reamer% !i)es ' *o+es

eamers come in si!es "# - $%", all with a taper of "."2. eamer design isidentified by the triangle symbol on the handle.

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R, -1, R15-R4, R45-R , R ,-14,

Reamer% Re(ommen+e+ use

A reamer is the most effective hand instrument in straight canals. 't is used bycontinuous rotation (upper picture) when the resistance is small or moderate and by

balanced force (lower picture) when the resistance is greater.

'n curved canals ledging easily occurs with even small reamer si!es if instruments arenot pre-curved. eamers are excellent instruments in straight canals but poorlyadaptable to curved canals.

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Reamer% !a/et0 tips

eamers can be rotated only using moderate pressure. *se of force, particularly with smaller si!ed instruments, may result in distortion of the helical

structure and ultimately in fracture. +ach instrument should be checked for symmetry by rotating it against an even background before introducing it into the canal.


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. K-FILE

K-/ile% esi&n ' !tru(ture

-files are manufactured from square or sometimes triangular steel wire that istwisted to give the typical shape of a -file. The angle between the long-axis and thecutting blade is greater than in a reamer, and therefore preparation by a -file iseffective both in rotary and filing motion.

The tip of the instrument is cutting which makes the -file best suited for the preparation of straight canals. mall -files (' / "# - $ ) can be also used in curvedcanals without the risk of ledging. mall -files are particularly good for the initial

preparation of very narrow canals.

#


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K-/ile% !i)es ' *o+es

-files are produced in si!es "# - $%", all with a taper of "."2. -file design isidentified by the square symbol on the handle.

K,#-1, K15-4, K45- , K ,-14,

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*. FLEXOREAMER

Fle oreamer% esi&n ' !tru(ture

4lexoreamers are manufactured from a triangular steel wire that is twisted to give thetypical shape of a reamer. The angle between the long-axis and the cutting blade issmall, and therefore preparation by flexoreamer is effective only in rotatory motion.

The tip of the instrument is non-cutting (5bat-tip5, 5inactive tip5) making flexoreamer

well suited for the preparation of evenly curved canals without risk of ledging.

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Fle oreamer% !i)es ' *o+es4lexoreamers come in si!es $ - %", all with a taper of "."2. eamer design isidentified by the triangle symbol on the handle.

4lexoreamers are best distinguished from normal reamers by the si!e code at the topof the instrument7 in flexoreamers the colour of the number is the same as the colourof the handle.

Fle oreamer% Re(ommen+e+ use

The flexoreamer is well suited both for straight canals and slightly curved canals. 't prepares dentin in rotation but not if used as a file. The cutting efficiency and usabilityof flexoreamers are excellent. 'n slightly curved canals the recommended techniquesare continuous rotation (upper picture) when the resistance is small and balancedforce (lower picture) against greater resistance.

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Fle oreamer% !a/et0 tips

4lexoreamers can be rotated only using moderate pressure. *se of force, particularlywith smaller si!ed instruments, may result in distortion of the helical structure andultimately in fracture. +very instrument should be checked for symmetry by rotating it

against an even background before introducing it into the canal.

. FLEXOFILE

Fle oFile% esi&n ' !tru(ture

$$


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4lexofiles are manufactured from triangular (note8) steel wire that is twisted to givethe typical profile of a -file. The angle between the long-axis and the cutting blade is

bigger than in reamers, which is why preparation by flexofile is effective both inrotating motion and in filing motion (up and down movement)

The tip of the instrument is non-cutting (5bat-tip5)which makes the flexofile well suitedfor the preparation of evenly curved canals without the risk of ledge formation

Fle oFile% !i)es ' *o+es

4lexofiles come in si!es $ - %", all with a taper of "."2. -file design is identified by

the square symbol on the handle.

4lexofiles can be best distinguished from normal -files by the si!e code at the top ofthe instrument7 in flexofiles the color of the number is the same as the color of thehandle.

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Fle oFile% Re(ommen+e+ use

4lexofile is suited for both straight canals and slightly curved canals. The flexofile prepares dentin effectively both in filing motion (up and down) and when rotated. 'nslightly curved canals the recommended techniques are continuous rotation (lower

picture) when the resistance is small and balanced force (upper picture) againstgreater resistance. *se of continuous rotation is limited as compared to reamers

because of the screwing effect typical of -files.

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He+stroem File% !i)es ' *o+es

9edstroems come in si!es "3 - $%", all with a taper of "."2. 9-file design is identified by the circle symbol on the handle.

H1,-H4, H45-H , H ,-H14,

He+stroem File% Re(ommen+e+ use

9edstroem can be used both in straight canals and curved canals. The hedstroem prepares dentin effectively only when using a filing, up and down motion. 'n curvedcanals, files (si!es 2":2 and bigger) must be pre-curved to correspond to the shape of the curve. 9-files must always fit loosely in the canal to avoid risk for fracture. This is

easily obtained by selecting a smaller 9-file after each rotating instrument. mall

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si!es up to ;2 can be used down into full preparation length while bigger si!es areoften used $ - & mm short.

He+stroem File% !a/et0 tips

9edstroem files show a greater risk for fracture than reamers and -files if used in awrong way. 9owever, correctly used 9-files rarely fracture. 9edstroem must alwaysfit loosely in the canal and they must never be rotated. 'n curved canals 9edstroem-files are pre-curved to correspond to the shape of the canal. efore introducing theminto the canal, all 9edstroem files must be inspected for possible earlier damage to theinstrument and discarded immediately if an asymmetry in the cutting area is found.

F. $I"I

$#


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$iti File% Re(ommen+e+ use


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2. Rotar0 preparation instruments

$6


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A. ro "aper

ro "aper% esi&n an+ !tru(ture

2"


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>roTaper instruments are prepared from round nickel-titan wire by grinding. 1ross-section of the instruments shows a triangular structure with three cutting points and noradial lands. >roTaper instruments have a non-cutting tip that guides the instrument inthe canal and reduces the risk for ledge formation.

The convex triangular cross-section which reduces the contact area between the fileand dentine. This greater cutting efficiency has been safely incorporated through

balancing the pitch and helical angles. A progressively tapered file engages a smaller!one of dentine which reduces torsional loads, file fatigue and the potential for

breakage. 't clinically serves to improve flexibility, cutting efficiency and typicallyreduces the number of recapitulations needed to achieve length, especially, in tight ormore curved canals.

ro "aper% !i)es ' *o+es

>roTaper instruments are manufactured in six si!es7 " ree s apers and three

finishing files. ? file (no color ring) is $6 mm long and has varying tapers of &. @( $), $6@ ( 6), and 2."@ ( $%). The tip of the instrument is ".$6 mm in diameter.$ (violet) has a tip diameter of ".$3 mm and a taper from 2@ ( $) to $$@ ( $%).2 (white) has a tip diameter of ".2" mm and a taper from %@ ( $) to $$. @ ( $%).

The diameter of all three haper files at $% is the same, $.$6 mm.

4$ file (yellow) has a tip diameter of ".2" mm. The taper is 0@ at $ and . @ at$%.

42 (red) has a tip diameter of ".2 mm. The taper is 3@ at $ and . @ at $%.4& (blue) has a tip diameter of ".&" mm. The taper is 6@ at $ and ." @ at $%.The diameters of the 4 files at $% are $."2 mm, $.$$ mm and $.$# mm, respectively.

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ro "aper% Re(ommen+e+ use

>roTaper is used in a rotating contra-angle with a high torque and a constant speed of2 " - & " rpm employing only light pressure.

Buidelines7$. Cork instruments to light resistance and never force them.2. /nly use instruments in a well irrigated and lubricated canal.&.The appropriate finishing file passively follows the canal to the desired lengthDthen is immediately withdrawn.%. *se in constant rotation at a speed of 2 "-& " rpm.

. 1lean flutes frequently and check for signs of distortion or wear.

The >roTaper technic7+xplore the root canal with a stainless steel


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The ? (no colour ring) is then used with a brushstroke action to selectively removedentine, relocate the canal away from furcal danger and achieve straight line radicularaccess. Cith improved access, the ? is passively fit a little deeper into the canal untilit encounters light resistance. ounce off this resistance and brush out of the canal inan apical to coronal direction. 1ontinue with the ? until about two thirds of the

overall length of its cutting blades are below the orifice. onHt forget to irrigate.

/nce the pre-enlargement procedure is finished with excellent coronal two thirdsaccess, use a precurved $" hand file to negotiate the rest of the canal, establish

patency, and confirm working length. Chen working length is confirmed and asmooth BIJ + path to the terminus is verified, use haping file


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ro "aper% !a/et0 tips

/nly light pressure can be used with the instruments, never force them. >roTaper is anextremely effective instrument that cuts dentin smoothly. 'nstruments must therefore

be constantly cleaned and inspected. istorted instruments must be discardedimmediately. >roTaper is not used with a pecking motion, but lightly pressed forwardin the canal.

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. 6reat "aper

6reat "aper% esi&n an+ !tru(ture

BT instruments are prepared from round nickel-titan wire by grinding. 1ross-sectionof the instruments shows a *-file structure with radial lands that inhibit screwingeffect in dentin. BT instruments have a bat-tip (= inactive tip) that guides theinstrument in the canal and reduces the risk for ledge formation.

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6reat "aper% !i)es ' *o+es

BT instruments are produced in three si!es, 2", &", and %", and each si!e comes infour tapers7 $", "3, "# and "%. The si!e of the instrument is shown by the colour band,and the taper is indicated by the number of taper rings.

'n addition, three bigger instruments are included in the BT familyK si!es & , " and0", all with a taper $2, for preparation of very large canals and for coronal flare inother canals.

2#


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6reat "aper% Re(ommen+e+ use

BT instruments are used in a rotating contra-angle with a high torque and a constantspeed of ($ "-) & " rpm, while employing light pressure. +ach instrument is used for

to $" seconds in a pecking motion7 push forward - draw back - push forward etc. 'fthe instrument does not proceed in the canal, pressure must not be increased but asmaller instrument must be tried.

>reparation is based on a crown-down technique where the coronal and mid-part ofthe canal are prepared with four crown-down instruments before apical preparation.>reparation is finished by coronal flaring, using one or more of the three flaringinstruments. Always refer to the manufacturer5s latest instructions andrecommendations on the correct use of the instruments.

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6reat "aper% !a/et0 tips

/nly light pressure, similar to writing with a pencil, can be used with the instruments.istorted instruments must be discarded immediately. 1rown-down and apical

preparation instruments can be used one to five times, flaring instruments five to tentimes.

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*. roFile

roFile% esi&n an+ !tru(ture

>rofile instruments are prepared from round nickel-titan wire by grinding. 1ross-section of the instruments shows a *-file structure with radial lands that inhibitscrewing effect in dentin. >rofile instruments have a bat-tip (= inactive tip) that guidesthe instrument in the canal and reduces the risk of ledge formation.

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roFile% !i)es ' *o+es

>rofile comes in three series that have different tapers."%-series (taper "."%) includes si!es $ -% , #" and 6", all in lengths 2$ and 2 mm."#-series (taper "."#) includes si!es $ -%" in lengths 2$ and 2 mm.

/rifice shapers are shorter instruments ($6 mm) with tapers from "." to "."3 andwith a different color:si!e match than in other instruments, as follows7white ;2":" , yellow ;&":"#, red ;%":"#, blue ; ":"0, green ;#":"3, black ;3":"3.

roFile% Re(ommen+e+ use

>rofile is used in a rotating contra-angle with a high torque and a constant speed of2 "-&"" rpm, while employing light pressure. +ach instrument is used for to $"

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seconds in a pecking motion7 push forward - draw back - push forward etc. 'f theinstrument does not proceed in the canal, pressure must not be increased but asmaller : next instrument must be tried.

>reparation is based on a crown-down technique where the coronal and mid part of

the canal are prepared before the apical part. Always refer to the manufacturer5s latestinstructions and recommendations on the correct use of the instruments.

roFile% !a/et0 tips

/nly light pressure, similar to writing with a pencil, can be used with the instruments.istorted instruments must be discarded immediately. mall si!es and "% taper

instruments can be used in $ - teeth, "# taper instruments in - $" teeth.

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.7uante(7uante(% esi&n an+ !tru(ture

Luantec instruments are prepared from round nickel-titan wire by grinding. 1ross-section of the instruments shows a special structure of two cutting points and radiallands that inhibit screwing effect in dentin. Luantec instruments are manufactured intwo typesK the 1 series has a cutting tip that has limited ability to penetrate intodentin, and the I?-series with a non-cutting tip.

&2


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7uante(% !i)es ' *o+es

Luantec comes in a series of sixteen instruments with its own color code system anddifferent si!es and tapers as follows7$7 ;2 :"# 27 ;$ :"2 &7 ;2":"# %7 ;2 :"2 7 ;2 :" ;2 :"% 07 ;2 :" 37 ;2 :"# 67 ;%":"2 $"7 ;% :"2

A new starting set includes three nr. 2 instruments ($0 mm) with tapers $2, $" and"3, and three new finishing si!es are ", and #" , all in taper "2. Always refer tothe manufacturer5s latest instructions and recommendations on the correct use of theinstruments.

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7uente(% Re(ommen+e+ use

Luantec is used in a rotating contra-angle with a high torque and a constant speed of2 " rpm, while employing light pressure. +ach instrument is used for to $" secondsin a pecking motion7 push forward - draw back - push forward etc. 'f the instrumentdoes not proceed in the canal, pressure must not be increased but a smaller instrumentmust be tried.

>reparation is started in the coronal and middle parts of the canal that are flared withinstruments ;2 :$2, ;2 :$", ;2 :"3 and ;2 :"#. This is followed by a sequential useof the instruments from % ("2:2 ) to 6 or $" up to the preparation length, when

possible with normal pressure. 'n larger canals, the preparation may be continued withsi!es " - #".

'n large canals that are easily prepared the number of instruments may be reduced asfollows7$, %, 6, $".9owever, this requires extensive experience in the use of these instruments. Alwaysrefer to the manufacturer5s latest instructions and recommendations on the correct useof the instruments.

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Ra*e% !i)es ' *o+es

The a1e instruments are produced as M>re- a1eM instruments with a short workingarea for preparation of the coronal canal and as M a1eM instruments for the

preparation of the middle and apical portions of the canal. Twenty different basicdesigns of a1e instruments are available, different lengths (2$ and 2 mm) give thenumber of instruments of ca. &". The tapers of the >re- a1e and a1e instrumentsvary from "# to $" and from "2 to "#, respectively (see tables in the photo folder).The si!es from ;$ to ;#" are available in the "2 taper series, while a1e instruments

in the "% and "# series have only three si!es (;2 - ;& and ;2" - ;&"). a1e isavailable also in four sets, designed for preparation of canals with different si!es andshapes, or to be used with different techniques (crown down, step back, e.g.)

Ra*e% Re(ommen+e+ use


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The a1e instruments are used with low torque at a speed of &"" - #"" rpm. Torquesettings are available from the manufacturer for different motors, such as +ndostepper (picture in the main window). The manufacturer recommends the use of >re- a1efiles ;%":$", ;& :"3, ;&" and ;%":"# for 1rown down procedure. +xcept the ;%":"#this files are integrated in the prefabricated sequences


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F.Fle Master

Fle Master% esi&n an+ !tru(ture

4lexmaster is a rotary


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Fle Master% Re(ommen+e+ use

The manufacturer recommends the usage of 4lexNaster within a speed of $ "-&""rpm. A torque control motor is useful. epending on the difficulty and wideness ofcanals the following sequences are recommended and offered in a asic it with the'ntro4ile7

Cide canals7 blue sequence with7 ;&" ."#, ;2 ."#, ;2" ."# and ;&" ."%Nedium canals7 red sequence with7 ;2 ."#, ;2" ."#, ;&" ."% and ;2 ."%

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mall canals7 yellow sequence with7 ;2" ."#, ;&" ."%, ;2 ."% and ;2" ."%Apical shaping7 green sequence with7 ;2" ."2, ;2 ."2, ;&" ."2 and ;& ."2

Fle Master% !a/et0 tips

The number of file usages should be calculated. A control sheet makes this workeasier with writing down a cross for every usage in a canal. After at least eight timesshaping of canals, the file should be discarded.

6.K3

K3% esi&n an+ !tru(ture

%"


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The cross section of a & instrument reveals three cutting blades with slightly positiverake angles, followed by radial lands. Two of the radial lands have been partlyreduced ( adial Iand elief) in order to improve the cutting efficiency of the file. Thesafe-ended non-cutting tip of the & instrument follows the root canal and reducesrisk of transportation.

& instruments have a MOariable 1ore iameterM, or variable flute depth. The proportion of the core diameter to the outside diameter is greatest at the tip, wherestrength is most important. The instruments also have a variable helical flute angle toreduce screwing effect.

K3% !i)es ' *o+es

& rotary instruments are available in a variety of si!es, lengths and tapers (see popup pictures for details). The picture in the main window above shows a B >ack set(Breater:Braduate Taper). The taper is shown by the color of the silicone stopper anda color ring in the metal handle, the si!e of the tip is indicate by the other ring color inthe handle. & files are produced in lengths of $0 mm - &" mm, depending on thetaper and si!e of the tip.

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K3% Re(ommen+e+ use

The following instructions are a brief guide for preparing the maGority of root canals.Iarger canals require less preparation in the coronal and middle portions but morecleaning with sodium hypochlorite. The guidelines below follow the principles of astep-down technique.

$. >lace rubber dam and cut an access cavity. +nsure there is straight-line access intoat least the coronal portion of all the canals.2. 'nsert a si!e $" file into each canal to check there is an unobstructed pathway forat least $:2 to &:% of the estimated canal length. 1anal length estimated from pre-operative radiograph.&. >lace an /rifice /pener taper $" into the canal(s) and penetrate for a fewmillimetres. peed 2 " rpm and using a slow gentle in and out movement%. >lace an + TA lubricant into the canal opening(s). Cork an "3 taper orifice opener&-% mms further into the canal.

. 'rrigate with sodium hypochlorite using a gauge 20 or &" irrigation needle.#. Neasure the working length of the canal with a file with the aid of an apex locator or a radiograph. +stablish apical patency by passing the $" file passively through theapex by no more than $."mm.0. egin filing with & "# tapered instruments. peed 2""-2 " rpm using light even

pressure with a slow in and out movement. *se each instrument for no more than #seconds.

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3. 4iles used in sequence from the largest to the smallest. >lace silicone stops on theinstruments at the working length. tart with si!e & , then &", 2 , 2", in a run down tosi!e$ . epeat the step-down from si!e & until si!e 2" reaches the working length.6. 'rrigate after alternate instruments and at completion of filing$". 1heck apical patency with si!e $" file.

ifficult fine and long curved canals4or those occasional difficult canals which are long, very fine and curved use both "%tapers and "# tapers./pen the coronal and middle thirds as described above, the use & starting with si!e&" "# followed by &" "%, then 2 "# followed by 2 "%, and finally 2" "# and 2" "%.'f this method does not reach the working length then widen the guide path with hand

files from si!e $" to $ and then 2" at the full working length. Another run of "#Hsand "%Hs from &" down to 2" will complete the preparation.

& B->ack (Braduating Taper) 'nstrumentation Buide$. /btain traight-Iine Access using the IA Axxess kit.2. Iocate the canal orifices and obtain coronal patency using hand files.&. egin 1rown-down by taking the .$2 Taper & haper to resistance (the .$2 Taper

& haper is designed to open the orifice only).%. Take the .$" Taper & haper to resistance.

. +stablish working length. +stablish this with your +lements iagnostic *nit. Aradiograph may be taken to assist in working length determination.#. Take ."3 taper & haper to resistance.0. Take the ."# Taper ;2 & 4ile to resistance. Nany canals will be finished after thisstep.3. 'n more difficult, curved and narrow canals you have the option of using a ."%Taper ;2 & 4ile and a ."2 Taper ;2 & 4ile until working length is achieved.

ecapitulate back to ."%, then ."# taper, if possible.6. Take each instrument to resistance at &""-& " >N in an electric torque controlmotor, using each instrument for no longer than -0 seconds.

1linical TipsP +stablish a glide path with hand files. 1onfirm patency between all rotary files witha ;"3 hand file.P 'rrigate copiously, alternating between sodium hypoclorite and mear1lear ($0@

+ TA containing antimicrobial and wetting agents).P *se very light pressure. rocedure >ack 'nstrumentation Buide$. /btain traight-Iine Access using the IA Axxess kit.2. Iocate the canal orifices and obtain coronal patency using hand files.&. egin 1rown-down by taking .$" Taper & haper to resistance.%. Take ."3 taper & haper to resistance.

. +stimate apical si!e.#. egin 1rown own using a si!e ;%" & 4ile.

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0. +stablish working length. +stablish this with your +lements iagnostic *nit. Aradiograph may be taken to assist in working length determination.3. 1omplete 1rown own preparation with a ;& & 4ile, ;&" & 4ile, ;2 & 4ile,

by taking each instrument to resistance at &""-& " >N in an electric torque controlmotor, using each instrument for no longer than -0 seconds.

1linical TipsP +stablish a glide path with hand files. 1onfirm patency between all rotary files.P 'rrigate often, alternating between sodium hypoclorite and mear1lear ($0@ + TAcontaining antimicrobial and wetting agents).P *se very light pressure. rocedure >ack will work in many cases, but all canals are different andadditional si!es of & 4iles may be required. Jou will want to begin with a & 4ile &si!es larger than your estimated apical diameter.

K3% !a/et0 tips

All rotary files can break when used carelessly. Always inspect the files before use todetect any asymmetry in the light reflection pattern. 4ollow manufacturer5s detailedinstructions regarding speed, pressure, technics (e.g. pecking), si!es and number ofuses per instrument. +xternal motors can be helpful to maintain even torque and speedto further reduce the risk of file fracture.

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H.En+o!e8uen(e

En+o!e8uen(e% esi&n an+ !tru(ture

+ndo equence is a rotary Hs) along the shank ofthe instrument. espite of constant taper, A1> should result in reduced contact area

%


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during preparation, which according to the manufacturer helps keeping the filecentered in the canal and reduces the torque requirements of the file. To further reducerisk for screw effect, the +ndo equence file has both variable pitch and variablehelical angles.Iike the a1e rotary file, +ndo equence file has been subGected to the process of

electro polishing, which can be detected by the glossy surface of the metal. Accordingto the manufacturer electro polishing improves the physical properties of theinstrument.

En+o!e8uen(e% !i)es ' *o+es

+ndo equence files are manufactured in tapers "# and "%. The smaller "% files have agolden shank, while the "# files have a silver color. "% instruments are available insi!es $ - %"K for the "# files two additional si!es of % and " are also made. 4orinitial canal preparation, an intermediate file with a si!e 20 and "% taper is available

(+xpeditor file). The regular si!ed files are made in three lengths7 2$, 2 and &$mm.1olor coding shows the tip si!e according to the ' / color standard system.

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En+o!e8uen(e% Re(ommen+e+ use

+ndo equence rotary files are used with only very slight pressure for a short time in

the canal. The recommended speed is "" - #"" rpm in electric handpiece. Afterinspection of the canal with a ;$" manual instrument ( -file), the recommendedtechnique is crown-down preparation. Always check for the latest instructions by themanufacturer for the correct and recommended technique.

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En+o!e8uen(e% !a/et0 tips

Any rotary file can break when used carelessly. Always inspect the files before use todetect any asymmetry in the light reflection pattern. 4ollow manufacturer5s detailedinstructions regarding speed, pressure, technics, si!es and number of uses perinstrument. +xternal motors can be helpful to maintain even torque and speed tofurther reduce the risk of file fracture. +ndo equence files are used with a very slight

pressure, each file is only a short time in the canal.

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3. Instruments !el/ Assessment

Hand instruments "rue False

eamers are always made of triangular steel wire

eamers are always made of square steel wire

eamers have a low angle between the long-axis and the cutting blade

The symbol of a reamer is a triangle

A MclassicalM reamer has an actively cutting tip

eamers are manufactured in si!es ;"# to ;$%"

The optimal way of using a reamer is rotation by the clock

eamers cannot be used with the balanced force technics

eamers are not effective in filing motion

-files are always made of square steel wire

The symbol of a -file is a square

The angle between the long-axis and the cutting blade in -files isgreater than in reamers

The optimal instrumentation technics with -files is balanced force

alanced force technics helps to minimi!e screwing effect with -filescrewing effect is a smaller problem in -files than in reamers

A MclassicalM -file has an actively cutting tip

Actively cutting tip help -files to avoid transportation and ledging

mall -files of ;"# - ;$" should not be using for instrumentation ofnarrow, calcified canals


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roTaper does not have radial lands

>rofile has radial lands

't is not necessary to inspect the canals with hand instruments before usingrotary9and instrumentation should be done to si!es $ - 2" before startingrotary

"# taper instruments are generally more flexible than "% taper instruments

/rifice shaper:opener instruments have always "2 - "% taper

9igh torsional loads increase fracture risk

4ile fatigue increases fracture risk

otary files can be used in $ - teeth, depending on the resistance andrecommendations of the manufacturer

otary instruments can be re-used in easy canals even if they areslightly distorted

otary files must always be in vertical motion (going down or up)

BT files have a varying taper in each instrument

a1e files have a varying taper in each instrument

>roTaper files have a varying taper in each instrument

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Documents

7602224 Endodontic Instrument