Protaper Universal

8/13/2019 Protaper Universal

1/21

1

Universidad de SevillaFacultad de Odontologa

Departamento de Estomatologa

PPAATTOOLLOOGGAAYYTTEERRAAPPUUTTIICCAADDEENNTTAALLIIIIII

CCuurrssoo22001133--1144

INSTRUMENTACINROTATORIA CON

PROTAPER UNIVERSAL


2/21

2

INSTRUMENTACIN ROTATORIA HORARIA CONTINUACON EL SISTEMA PROTAPER UNIVERSAL

El sistema de limas que utilizaremos es el Protaper Universal.


3/21

3

En estos esquemas D1 se corresponde en la actualidad con D0.


4/21

4


5/21

5

PROTOCOLO DE USO PARA LAS LIMAS PROTAPER UNIVERSAL:

- Estos instrumentos no deben sumergirse en soluciones de hipoclorito sdico.

- Descontaminacin de los instrumentos: seguir estrictamente las instrucciones de

descontaminacin que dice el fabricante; primero limpiar y descontaminar losinstrumentos y sus soportes, luego esterilizarlos en bolsas en autoclave a 134C y 3 bardurante 18 minutos.

- Irrigacin frecuente y abundante.

- Establecer un camino permeable (glide-path) del conducto con limas manuales por lomenos hasta un ISO 015.

- Usarlo en rotacin continua a una velocidad de 150-350 RPM con ligera presin apical.

- Limpiar las helicoides frecuentemente y revisar si aparecen signos de distorsin odebilitamiento.

- Para un uso ptimo, se recomienda utilizar motores con control de torque.

- Usar las limas de preparacin (S1, S2 y SX) con un movimiento de cepillado hacia fueradel conducto para crear un acceso en lnea recta al conducto.

- Usar las limas de acabado (F1, F2 , F3, F4 y F5) sin movimiento de cepillado.

- Usar las limas de acabado de manera correcta para llegar pasivamente a la longitud detrabajo y posteriormente sacarlas.


6/21

6

Protocolo clnico:

1. Crear un acceso recto al orificio del conducto.

2. Siempre irrigar y confirmar que existe un camino permeable del conducto (glyde-path)

con una lima manual ISO 015.

3. Secuencia clnica:

- Localizar el orificio de entrada del conducto.- Usar pasivamente una lima manual ISO 015 hasta encontrar resistencia (glyde-path).- Usar la lima de preparacin S1con movimiento de cepillado hasta la misma distancia

que lleg la lima manual ISO 015.- Repetir esta secuencia hasta que se determine la longitud de trabajo con la lima manual

ISO 015 y la lima S1 llegue a dicha longitud de trabajo.- Usar la lima de preparacin S2con movimiento de cepillado hasta alcanzar la longitud

de trabajo.- Reconfirmar la longitud de trabajo.- Usar la lima de acabado F1(movimiento de no cepillado) llegando en cada insercin a

mayor profundidad hasta alcanzar la longitud de trabajo.- Medir el foramen con limas manuales.- Usar la correcta lima de acabado (F2, F3, F4, F5)con el mismo movimiento de no

cepillado hasta la longitud de trabajo si se requiere ms ensanchamiento o el foramenes mayor.

- Si es necesario, usar la lima SXcon movimiento de cepillado para alejar la partecoronal del conducto de la furca y/o crear ms ensanchamiento coronal.


7/21

7


8/213

Advantages ofNiTi Rotary Systems

In the last decade, after generations of little change, various technological advances(e.g. microscopes, ultrasonics, new obturation concepts and materials) have

revolutionised the discipline of endodontics. It is the rotary Nickel Titanium (NiTi)instruments, however, that have had the greatest impact. Particularly advantageouswas the advent of instruments of increased taper with their crown down preparationcreating predefined shapes.

The 5 main advantages of the NiTi rotary systems are:

1. Predictable results every time even when dealing with curvedcanals.

2. Time Saving: with practice a standard molar can betotally cleaned and shaped in far less time than handinstrumentation.

3. Less Fatigue for the operator compared to handinstrumentation.

4. Less post-op pain owing to debris being extruded from thecanal during the crown-down technique instead of being

pushed through the apex during step-back.5. Less Transportation of canals

There are 4 aspects of NiTi rotary files that need to be discussed in order to obtain aclearer understanding of their correct and safe use.

1. The use of Hand Files

There is a misconception that hand files are unnecessary when using NiTi rotaryfiles. This could not be further from the truth. In fact, the role of hand files has beenredefined since the introduction of NiTi rotary files. Hand files are complementary toNiTi rotary files, and serve the following functions:

To determine straight line access

To give information regarding the root canal system anatomy

To 'scout' the canal to either create or confirm a 'glide path'

To act as 'patency finders'

To determine working length To finish the preparation when there is an 'irregular glide path'


9/214

2. Tapers

Most dentists are now aware of the concept

of tapers. For nearly 50 years 'conventional'hand files have had a constant taper of 2% i.e.measuring from the tip for every millimetre we movecoronally, the diameter of the instrument increasesby 0.02mm. Since the introduction of NiTi rotaryinstruments we have seen a whole range of tapersup to 12%. However, regardless of the percentagetaper of the file, the taper was always constant foreach individual file (see figure 1).

That rule has also changed recently with the adventof the ProTaper NiTi rotary filing system. The fileshave variable tapers within each individual file (seefigure 2).

ProTapers were the brainchild of four endodontistswho were looking to design a safer file whichwould give increased torque strength and increased

resistance to metal fatigue.Adequate taper is so important to ensure betterpenetration of irrigants in order to obtain bettercleaning of the root canal system. It also provides betterhydraulics for better Gutta Percha compaction.

3. Separations

The benefits of using rotary NiTi files are well documented. Therefore, why isnt

everybody using them? Price is not the reason; although more expensive per individualfile compared to hand files, rotary NiTi files are more cost effective owing to theirefficiency. It is the fear factor of separated instruments that is still preventing somepractitioners from taking the next step into NiTi rotary files.

There are only 2 ways NiTi rotary files will separate:

1. Excessive Torque:Torque is a resistance to rotation; basically you have exceededthe strength of the instrument.

2. Metal Fatigue:When a NiTi rotary file is rotated around a curve it goes from

maximum stretch to maximum compression. Sooner or later it will experiencemetal (or cyclic) fatigue. Metal fatigue is accumulative.

figure 2


figure 1


10/215


figure 3 X-Smart Unit

Please refer to the following chart for factors affecting both Torque Failures and MetalFatigue failures. As an example, with ALL OTHER FACTORS BEING THE SAME, if you

increase the pressure on the file you increase the likelihood of Torque Failure.Torque Failures Metal Fatigue Failures

Pressure Curvature

Curvature Radius

Surface Area Diameter of instrument

R.P.M. Taper

Lubrication No. of forward/reverse cycles

Referring to this chart, it now makes sense that in the straight portion of a canal weneed high torque strength (large tapers/diameters). However, around the curve weneed flexibility and increased resistance to metal fatigue. Therefore, we choose asmall taper instrument. It can now be seen that if you have a constant taper in afile then that file cannot have high torque strength and at the same time have highresistance to metal fatigue.

The uniqueness of a variable tapered instrument e.g. ProTaper S1 is that it givesapical flexibility (small apical taper and minimum metal fatigue), but at the same timeincreased torque strength because of its larger coronal tapers.

In recent times with the introduction of the latest generation of torquecontrolled motors (see figure 3), an increase in the safe use of NiTifiles has occurred. These motors are programmed so that the optimaltorque for each file can be selected.

Rotary files should be used passively within the canal, andtheir use continued as long as they move easily in anapical direction. Never force NiTi rotary files. NickelTitanium is so flexible that if forced it will buckle andeventually succumb to metal fatigue.

There are typically 3 factors affecting a rotary file from passively moving in an apicaldirection:

1. Canal size/Instrument size

2. Debris INTRACANAL and INTRABLADE. Ensure that the canal is free of debrisby using copious irrigation and frequent recapitulation. Ensure that flutes are freeof debris.


11/216

3. Root Canal Anatomy e.g. mid-root curvature(may appear calcified on the radiograph) or

abrupt apical curve. We are aiming to obtaina smooth, reproducible glide path so thatthe tip of our rotary instrument can passively,accurately and safely follow the canal.

4. Cross-Section of Cutting Blades

Rotary NiTi files can either be classified as ACTIVE(in one example semi-active) or PASSIVE (see figure4). Basically an active file will rotate and cut in a canal without pressure; a passive

file needs apical pressure to cut.When using a rotary NiTi file it is essential to knowthe cross-sectional design of that file in order toknow how it can and should be used. For instancefigure 4 shows the ProFile in cross-section which isan example of a passive cutting blade. The radiallands 'plane' the walls of the canal, and althoughrepeated return is not recommended, if you do you

are less likely to get transportation of the canal.Figure 5 shows the ProTaper (SX, S1, S2, F1, F2)in cross-section, which is an example of an activecutting blade. No radial lands, and the slightlyconvex triangular shape reduces the contact areabetween the blade of the file and dentine. This feature serves to enhance cuttingefficiency, reduces torsional friction and improves safety. However, this type ofcutting blade needs to be used in a techniquewhere repeated return is prohibited to preventtransportation of the canal.

To follow is an explanation of the files in the ProTapersystem and a detailed step-by-step technique ontheir safe use. Figure 6 serves to emphasize thetypical anatomy found in a mandibular molar.One needs to appreciate the position, size andmorphology of the pulp chamber. Often the floorof the pulp chamber is constricted creating internal

triangles of dentine. Additionally, one should bealert to root curvatures, external root concavitiesand root canal system anatomy.

figure 5 ProTaper

figure 6


figure 4 ProFile


12/217

figure 7

The NiTi ProTaper system is comprised of just three shaping and five finishinginstruments. The instruments have handles that are 13mm long to facilitate access

and are available in 21, 25 or 31mm lengths. TheProTaper files have non-cutting guiding tips to helpauger soft tissue out of the canal. The ProTaperinstruments are only used in canals that have aconfirmed 'smooth, reproducible glide path' (moreon this shortly).

The SX file (figure 7) has a gold coloured handlewithout any identification rings. It has an overalllength of just 19mm. This shorter length allows itto be introduced into more restrictive areas whereaccess is a problem. SX may be used to optimallyshape canals in shorter roots, relocate canals away from external root concavitiesand produce more shape, as desired, in the coronal one-third of canals in longerroots. SX has 9 increasingly larger tapers ranging from 3.5% to 19%.

The SXdiameters between D6D9 may be equatedto the Gates Glidden drills 14. Strategically, theSX file is used with a lateral brushing motion tocut dentine, between D6D9, on the outstroke.Importantly, the apical extent of SX should NOTengage dentine; rather passively follow a canalthat has a confirmed smooth, reproducible glidepath. The S1(figure 8) has a purple identificationring and exhibits 12 increasingly larger tapersover the length of its cutting blades. The S2hasa white identification ring and exhibits 13 tapers

over the length of its cutting blades. The S1 is designed to prepare the coronal one-third whereas the S2 is designed to enlarge and prepare the middle one-third of thecanal. In general, each instrument engages, cutsand performs its own crown-down preparation.

The first three finishing files, termed F1, F2 and F3(figure 9) have yellow, red and blue identificationrings on their handles corresponding to tipdiameters of 0.20, 0.25 and 0.30mm respectively.

The F1, F2 and F3 have fixed tapers of 7%, 8%and 9% in their apical extents, respectively, anddecreasing percentage tapers in the coronal two-thirds of their cutting blades.

figure 8

figure 9



13/21


14/219

Preparation Sequence

figure 12

The preparation sequence that will be described involves

the following steps: Scout the coronal 2/3rds of the canal

Pre-enlargement of the coronal 2/3rds

Scout the apical 1/3rd of the canal

Finish the apical 1/3rd preparation

1. Scout Coronal 2/3rds

For the purposes of this exercise, 'scout' means using #10 and #15 handfiles. Thesescouting files give you an idea of:

cross-sectional diameter of the canal

canal anatomy

access: where is the handle? Is it standing up tall? Do I have radicular and coronalaccess? The handles of small handfiles are frequently off axis in furcated teeth dueto internal triangles of dentine (see page 6).

Following complete straightline access, a #10handfile may be used to scout a portion of theoverall length of the canal (figure 12). The #10handfile will create more space than its numericalname would suggest as it is 0.10mm at D0andtapers to 0.42mm at D16. Small #10 and 15handfiles are used to either create sufficient spaceor to confirm available space prior to using more

efficient NiTi rotary files.We will use 2/3rds as our step 1 scoutingdistance, but this will vary from case to case.Wiggle in (can use small watch winding motion)#10 handfile until it meets resistance (until it issnug), and then pull back. Note the length that the #10 reached. Feed it in again,snug, pull back etc. Do this about 6 times. Remember at this stage you are not tryingto get to working length.

The #15 handfile is 50% larger at D0than the #10. It is 0.47mm at D16, and servesto expand and refine the glide path. Before safely introducing a ProTaper into a canal,sufficient space must exist to accommodate and guide its modified guiding tip.


15/2110

Wiggle in #15 handfile until snug and then pullback (figure 13). Again do this about 6 times. It

should reach the same length as the #10 handfile.If experiencing any problems (especially in vitalcases) use a lubricant such as Glyde. Irrigate,recapitulate with #10 handfile (push/pull) andre-irrigate.

You have completed Step 1:Scout Coronal 2/3rds of the canal

2. Pre-enlargement ofCoronal 2/3rds

ProTaper instruments are not end cutting, butare rather designed to safely follow a smoothreproducible glide path. S1 has a D0 diameterof 0.17mm and its modified guiding tip easilyfollows the part of the canal that was previouslyscouted with #10 (0.10mm) and #15 (0.15mm)handfiles.

The S1 is used with virtually no apical pressure.When any rotary instrument ceases to progressivelyand passively advance deeper into a canal,it should be removed and its blades cleaned.Importantly, the S1 expands, refines and smooths the glide path. I like to think of theS1 as our 'workhorse'.

Set the motor at the correct torque for S1 (figures 15 & 16). Advance

the S1 to the same length as the #15 handfile reached (figure 14). DO NOTGO ANY DEEPER. If you have reached the required depth, DO NOT RE-ENTERcanal with S1. Remember these files have active cutting blades and repeated

return is unnecessary and fraughtwith danger. If you did not reach therequired depth, then take the S1 outof the canal, clean the flutes andreintroduce in to the canal, butdeeper this time.

DO NOT GO BACK TOTHE SAME LENGTH.

figure 16


figure 14

figure 13

figure 15


16/2111

Shaping files can be used with a 'brushing' motion.

Once required depth obtained then irrigate,

recapitulate with #10 handfile (push/pull) andre-irrigate.

Furcated teeth have internal triangles of dentine(figure 17) which should be removed during theinitial stages of treatment to facilitate shapingprocedures. Uprighting the handle of the smallersized hand files often requires refining andexpanding the access preparation in conjunctionwith removing the mesial triangle of dentine from

the cervical third of the canal.With just a single instrument, the ProTaper SX filemay be used to rapidly, effectively and safelyremove restrictive triangles of dentine (figure 18).

Set the motor for the correct setting for SX The SX is carried in to the canal and passively

allowed to advance until its apical movementslows.

The SX file is then lifted coronally about 1mmand its middle one-third blades between D6 andD9 (remember from page 7, these diametersequate to Gates-Glidden 14 drills) may beused. These middle one-third blades are usedin a lateral brushing motion to cut dentine onthe outstroke. Cut away from the furcation.Once lateral space has been created, then SX

will invariably advance passively deeper intothe canal.

The cycle of passive advancement followed bybrush-cutting dentine on the outstroke is repeatedto create lateral space so the rapidly tapering blades can progressively shape deeperinto the canal. Importantly, the apical extent of SX is NOT designed to cut dentine,but passively follow the glide path. The reason for the cutting blades on the apicalportion of SX is to help auger soft tissue out of the canal. The use of SX is continueduntil about 2/3rds of the overall length of its cutting blades are below the orifice

(figure 19). DONT FORGET: Irrigate, recapitulate with #10 handfile (push/pull) andre-irrigate.

You have completed Step 2: Pre-enlargement of Coronal 2/3rds.

figure 17

figure 18


figure 19


17/2112

3. Scout Apical 1/3rd

With excellent radicular access, a pre-measured

and pre-curved #10 handfile is used to scoutand negotiate the rest of the length of the canal(figure 20).

The #10 handfile is moved gently to theterminus, then minutely through the foramento establish patency. Repeat the 6 pullbackmovements done previously.

Irrigate

The #15 handfile follows the path of the #10,improves the glide path and dictates the nextclinical move. When it is difficult to pass smallhandfiles to length, then viscous chelators(e.g. Glyde) should be used to encourage themechanical objectives.

Determine working length with an electronic apexlocator (e.g. PROPEX) and confirm radiographically

(with #15 handfile) (figure 21). Repeat the 6 pullback movements (as donepreviously) to length with the #15 handfile(figure 22). Irrigate, recapitulate (#10 handfilepush/pull), re-irrigate.

We are now ready to finish the apical 1/3rdpreparation. However, we first must determine ifwe can use rotary files to do this or whether we

finish with handfiles. We do this by verifying if wehave a smooth, reproducible glide path.

You have completed Step 3:Scout Apical 1/3rd of the canal.

4. Finish Apical 1/3rd

A smooth, reproducible glide path is important. A

#15 handfile may be used to verify whether theapical one-third of a pre-enlarged canal has eithera smooth or irregular glide path (figure 23).


figure 20

figure 21

figure 22

figure 23


18/2113


figure 24

A smooth, reproducible Glide path is verified if a brand new #15 handfile can begently pushed over a few millimetres, and can passively slide to length.

If you encounter obstructions when trying to move the #15 handfile passively (asoutlined below) then you do not have a smooth, reproducible glide path. You,therefore, cannot expect a rotary file to be used in an area where a handfile couldnot go freely.

This is a critical technique:

1. Move the #15 file 1mm short of the working length and gently push back toworking length. Do this WITHOUT any twisting.

2. Move the #15 file 2mm short of working length and repeat the above.




Did you obtain a smooth, reproducible glide path?

NOthen finish the apical one-third by hand filing.

See p.15 for details on finishing with ProTaper Universal for hand use.

YESthen it is safe to finish the apical one-third with ProTaper.

Lets assume that we have a smooth, reproducible glide path and, therefore, willcomplete the preparation with ProTaper.

We commence with the S1 file (and NOT ProTaper finishing files).

Check correct torque setting on motor. Remember all ProTaper shaping files can be used with a 'brushing' motion.

S1 will now be taken to full working length(figure 24). When the S1 will not achieve length,passively remove the instrument, clean its cuttingblades and irrigate, recapitulate and re-irrigate.Appreciate that depending on the degree ofapical curvature, it may require one, two or three

passes to safely move the S1 to length. Once youhave reached working length with the S1, doNOT go back into the canal with this instrument.


19/2114

4. Finish Apical 1/3rd(continued)

Set the motor at the correct torque for S2

The ProTaper S2 (figure 25) with the whiteidentification ring on its handle is designed toperform its own crown-down work.

It carries another wave of shaping deeper into thecanal and will typically move easily to the desiredworking length on the first pass. Do NOT go backin to the canal with this instrument once workinglength has been achieved. Irrigate, recapitulate and re-irrigate.

The first ProTaper finishing file selected is theF1 (#20/.07) with the yellow identification ring(figure 26).

Set the motor at the correct torque for F1

The F1 is designed to smoothly blend the deep,apical 1/3rd shape into the middle 1/3rd of thecanal. Before using the F1 it is wise to reconfirm

working length, as a more direct path to theterminus has been created. The finishing files areused passively with short penetrating strokes until length is achieved. When the F1achieves working length, then it is withdrawn asthe shape is cut. Do NOT go back in to the canalwith this instrument. Irrigate, recapitulate and re-irrigate.

Following the use of the F1 (#20/.07) to length,

the foramen is gauged using a #20 handfile(figure 27). If the #20 handfile is snug at length,gently tap the handle of the file. If it remains inposition, the canal is fully shaped and readyto obturate. A #20/.07 F1 ProTaper to lengthis consistent with our cleaning and shapingobjectives in that it has kept the foramen size as small as practical. If using lateralcondensation, use the F1 GP for ProTaper. If using a ProTaper Obturator, use sizeF1.

If the #20 handfile is loose at length, then gauge the size of the foramen with a#25 handfile. If the #25 handfile is snug at length, then the canal is fully shapedand ready to pack.


figure 25

figure 26

figure 27


20/2115

The following procedures are only necessary if the#25 handfile as previously described was short of

length. The next ProTaper finishing file selected isthe F2 (#25/.08) with the red identification ring(figure 28).


The F2 is used passively and when length isachieved, it is withdrawn. Following the use of theF2 to length, the foramen is gauged using a #25handfile. If the #25 is snug at length and tapping

the handle does not move the file beyond the foramen, the canal is fully shaped andready to obturate. If the #25 is loose at length, then gauge with the #30 handfile. Ifthe #30 handfile is snug at length, then the canal is fully shaped and ready to pack.If the #30 handfile is short of length, then proceed to F3.


F3 (#30/.09) has the blue identification ring(figure 29). The F3 is used passively and, in morecurved canals, just short of length as the previous

rotary files have created a more direct path to theterminus. Following the use of the F3, the foramenis gauged using a #30 handfile. If the #30 issnug at length (do tapping test), the canal is fullyshaped and ready to obturate.

If the #30 handfile is loose at length, then proceedto F4 and F5 as necessary to easily complete these more open and straightforwardcases. Also in short canals or large straight canals, after initial negotiation ('scouting')

use the SX in a circumferential mode. It is not necessary to use the S1 or S2 inthese cases. Instead, after confirming working length, proceed to gauge the foramendiameter. Then use the appropriate ProTaper Finishing file to prepare the apicalterminus.

Finishing the preparation with ProTaper Universal forhand use

ProTaper Universal for hand use, with silicone handles, has the same design as its

rotary equivalent. The deep shape produced ensures superior root canal preparationsthan those obtained using conventional stainless steel files (figure 30).

The sequence is identical to that used when using rotary ProTaperUniversal files.

figure 28

figure 29



21/21

As mentioned previously, sometimes it is notpossible to obtain a glide path in the apical

third of the preparation (e.g. complex rootcanal anatomies). In these cases hand filingis recommended over rotary to complete thepreparation. ProTaper for hand use gives superiorcontrol, predictability and quality than currentlyavailable stainless steel files. ProTaper Universalfor hand use can be used either in a modifiedbalance force technique or in a reaming (backand forth) motion.

Obturation

Now that we are more frequently finishing ourapical preparations with larger tapers we needto review how we obturate these canals moreefficiently. We need to be more aware of tip sizesand apical tapers of the finishing files we areusing.

Let us first look at Lateral Condensation havingprepared a canal with ProTaper NiTi rotary files.If, for instance, our last ProTaper to length was theF1 (remember it has an ISO tip size of 20 and 7%apical taper) then dont waste your time tryingconventional 2% GP cones as your master points.Instead use a GP point for ProTaper F1 which willgive a snug fit to length. Minimal accessory GPpoints will now be needed. In fact, single cone

obturation may be sufficient (figure 31).The use of warm obturation techniques hasbecome popular in recent years. Materials suchas Thermafil result in ideal 3-D fills, thanks to theexcellent shapes produced by NiTi rotary files likeProTaper Universal. Continuing the tradition ofThermafil, the colour-coded ProTaper obturatorscorrespond to the matching ProTaper Universal

finishing files (figure 32).

figure 30

figure 31

fi 32

Documents

Protaper Universal