1

Problem Solving InEndodontics

10/20/2009 kmw12

2.

2

Pulp chamber is complex and intricate.So always problems should be expected.To handle such problems

1.

3.4.5.

10/20/2009

Extreme careGood observationSkillPatienceExperience

would be helpful.

kmw12

3

Evaluation of the Clinician

Before treating, answer the questions.

1. Do I have the experience ?

2. Do I have the skill ?

3. Do I have all the equipment needed ?

To provide this Endodontic treatment

10/20/2009 kmw12

7.

4

To avoid trouble in endodontics, treatmentprocedure should be involve proper

10/20/2009

1.2.3.4.5.6.

8.9.10.

Patient selectionTooth selectionIsolationAccess cavityCanal irrigationWorking lengthCanal preparationTrial fillingCanal obturationCrown restoration

kmw12

1.

3.

7.

9.

5

1.Patient selection limitations

Medically compromised patient

10/20/2009

2.

4.5.6.

8.

10.

Very old patientPoor oral hygieneRetain rootsCalculiCarious teethRestricted mouth openingPatient’s attitudePatient’s complianceCost

kmw12

1.2.2

5.6.67.

9.

6

2.Tooth selection limitations

Unrestorable tooth

Insufficient periodontal support

10/20/2009

3.4.

8.

10.

Root fractureBizarre anatomyNon--strategic toothExternal/external resorptionProcedural accidentCalcified canalPost retained crownsOpen apex

kmw12

7

Tooth selection

• X-rays1. proper diagnostic radiographs is

mandatory2. Tooth with more complex canal

anatomy and pathology, vertical orhorizontal parallax radiograph isnecessary

Root caries and heavy restorations.

10/20/2009 kmw12

1.2.23.4.5.

8

Indication for re--treatment

Signs of infected root canalSigns of periapical pathologyTechnically inadequate RCFDislodge of post retain crownBroken down crown restorations

10/20/2009 kmw12

9

3.Isolation

1. Remove all the carious dentineand bad restorations

2. Remove gum polyp3. Place matrix band and holder4. Restore with GIC5. Place rubber dam or

isolate with cotton role

10/20/2009 kmw12

4. Access cavity1. To remove the entire roof of the pulp chamber so that

the pulp chamber can be cleaned and canal entranceexposed.

2. To enable root canals to be located and instrumented byproviding direct-line access to the apical third of theroot canals.

3. To avoid damage to floor of the pulp chamber. Naturalfloor tends to guide an instrument in to the canalorifice.

4. To enable a temporary seal to be placed.

5. To conserve as much sound tooth tissue as possiblecompatible with above.

10/20/2009 kmw12 10

Root Canal Access.Learn and remember common variation of the root canal

systems.Plan entrance to the pulp chamber and the canals.Pulp morphology will dictate the shape and size of the coronal

access cavity preparationBe guided by the pre operative radiographs and more

radiographs toAvoid perforation

10/20/2009 kmw12 11

Perforations in access cavity prep

10/20/2009 kmw12 12

•Under preparation and over preparation of accesscavity should be avoided, If perforation occurs For theclosure of the exposure. The choice of material aremineral trioxide aggregate (MTA), Super EBA--orthoethoxybenzoic Acid or Ca (OH)2 may be used.

•over preparation of access cavity or excessive flaringof the coronal preparation can cause fracture of the

crown

10/20/2009 kmw12 13

Pain when removing pulp

Vital pulp remnant

Should be handled with pulpal and otherL.A.injection – Formocresol dressing for threedays

As well make a good careful observation for

more canals,

Un cleared pulp -

A perforation.

10/20/2009 kmw12 14

5.Canal irrigation

Minimum 2.5ml of irrigant (NaOCl)should be used after each fileAvoid Excess volume

Excess speed,needle binding the canal wall,

may lead to emphysemaShould be managed withSteroids and prophylactic antibiotics

10/20/2009 kmw12 15

Tissue emphysema

• Develops when air enters the periradicular tissuethrough the root canal, when attempt is made todry the canal with the air syringe. This shouldnever be done

• Use same syringe suck fluid out from the canaland use paper points to final drying out the rootcanal

10/20/2009 kmw12 16

–

••••

Calcium hydroxide dressing

• Weeping canal (Bleeding excudate cystic fluid)–––

Open apexLarge cystPerforation

Unnegociated canal

– Pulp remnent

Open apexRoot fracturePerio endo lesionRoot resorption

10/20/2009 kmw12 17

To induction of hard tissueformation

• Apexogenesis – continue apical rootdevelopment

• Apexification – close the wide apical foramen• Apical bone formation – elimination of apical

radiolucency• Cement formation – create a mechanical

barrier at a fracture line

10/20/2009 kmw12 18

To control of exudation or bleeding

• Reduction of inflammation and infection

• Arresting bleeding – devitalizing pulp remnant

• drying the canal – absorbing cystic fluid

10/20/2009 kmw12 19

To Control inflammatory rootresorption

• Remove infection

• Devitalized odontoblast

• Induce hard tissue formation

10/20/2009 kmw12 20

To pain control and devitalized thepulp

• Remove infection

- Bactericidal action

• Remove inflammation

- soothing action

• Devitalized the pulp

- fixing the vital pulp

10/20/2009 kmw12 21

1.

2.

3.

5.

5.Working lengthAverage tooth length

Radiographic length

First bound length

4. Pain length

Apex locator length

Calculate Provisional working length

Operative radiograph

+/- 2mm to apex;

Used formula & repeat the x-ray

10/20/2009 kmw12 22

6.Canal preparationTwo distinctions should be recognized

1.This is the only dental treatment thatdepends heavily on the tactilesensation of the fingers of the operator.

2.The ability of the clinician to visualizethree dimensionally the anatomy of thepulp.

10/20/2009 kmw12 23

Instrumentation Problems

Problems due to instrumentation couldbe due to1.Under instrumentation2.Over instrumentation3.Problems in curved canals4.Instrument separation

10/20/2009 kmw12 24

Under instrumentation leaves Debris or pulp tissue in RCcontinuing to disease the periapical and periradiculer

tissues and failure of RCT.

Filing beyond the apical foramen enlarging the apicalforemen, overzealous instrumentation can lead totransportation of foramen or the canal,

10/20/2009 kmw12 25

Curved Canals• Curved canals offer a wide range of

anatomical shapes that can lead toprocedural errors such as,

• Zipping

• ledge formation

• strip perforation

• apical perforation

• transportation

during cleaning and shaping10/20/2009 kmw12 26

Ledging / Transportation /Perforation

10/20/2009 kmw12 27

Zipping

When a curved foramen is filedwith a small file with pressureagainst the outer side of thecurvature, repeated filing Zips andtransport the foramen.The curved area of the foramen isnot cleaned and retains tissuedebris. Foramen cannot beobturated totally and failure of theRCT is certain.

10/20/2009 kmw12 28

An apical perforation should alwaysbe suspected when patient suddenlycomplaints of pain, or the root canalis getting flooded with blood, or ifthe tactile resistance felt on thefingers of the operator is suddenlylost.

10/20/2009 kmw12 29

Checking with a radiograph with filein position will help to detect theperforation. As for treatment in suchapical perforation both the iatral andnatural foramina should be attendedto and perfectly obturated

10/20/2009 kmw12 30

Apical perforation can take place even ina perfectly straight canal when the apicalforeman is needlessly enlarged whenfiling with files larger than the naturalforemen size, and beyond the actualworking length of the root canal. Thisjeopardizes, through extrusion of fillingmaterial when obturating, the repair atthe apical cemento- dentinal junction,.

10/20/2009 kmw12 31

Over instrumentation perforation can betreated by re--establishing the apical foremanslightly shorter than the natural, enlarging thecanal up to the new length with largerinstruments but maintaining the funnel shape.Then very carefully obturating to that length,preventing any extrusion. Apical barrier withMTA is another option.

10/20/2009 kmw12 32

the side of the canal when narrow curved canalsare cleaned. This can cause bleeding, anddamage the structural integrity of the root there

by leading to fracture of the root.

10/20/2009 kmw12 33

Strip perforation

When such perforation takes place repair isvery difficult. The perforation site can bedetermined with a paper point. After firstcleaning and drying the canal, carefully repairthe perforation with Ca(OH)2. Unless acalcific barrier is formed Surgicalintervention, with root resection or extraction

of the tooth may be needed.

10/20/2009 kmw12 34

File separation

Takes place when excessive filing force isused and if the file is old, bent, kinked orwhen the file is used in excess of the torquelimit And cyclic fatigue of the file material.

10/20/2009 kmw12 35

Fractured part in coronal 1/3rd

• In the straight portion of the canal, Loosen it witha H file or an ultrasonic instrument and pull thepart out with a H file or with a curved mosquitoforcep or a locked tweezer.It may even be flushedout if loosened sufficiently.

10/20/2009 kmw12 36

.

Fractured part in middle 1/3 ,or in apical 1/3 of the RC.

Special instrumentsAre available to disengage hold andremove separated instruments from root canals.Eg. Cancellier instrumentsTrepanbur,Messerann extractorsIRS Instrument remover (Dentsply) etc.

10/20/2009 kmw12 37

If it is not possible to disengage thefractured part, bypass the fractured partand do the cleaning and shapingobturate incorporating the part with in

the root filling.Subsequently surgical interference maybe needed. X-ray observation after threemonths, 06 months and after thatannually for at least five years, would bemandatory

10/20/2009 kmw12 38

To avoid file fracture

Avoid use of old worn-out kinked files.Use fine Vaseline coated files to gain a glide path.Check the file before and after every use. Alwayskeep the canal well irrigated and lubricated. Do notexceed fatigue limits. Before entering the apical 1/3,always establish a coronal flare in coronal and middle

1/3ds.

10/20/2009 kmw12 39

Trial filling

• Master points shouldinsert up to the workinglength

• Tug-back action should befelt

10/20/2009 kmw12 40

9.Obturation Errors

Are mainly due to,

– Improper sealing of apical foramen

– Improper sealing of coronal orifice ofRC

– GP shorter than apex

– GP and material beyond apex

– Voids in GP compaction

10/20/2009 kmw12 41

Obturation shorterthan the apex

Can result in micro leakage

May be due to legging

Dentine particles/ mud at apex

Improper cleaning and shaping.

Rx. Clean again and then obturate.

10/20/2009 kmw12 42

Material beyond the apex

Proper cleaning shaping creating thefunnel shaped radicular cavity will

prevent material leaching out due to verynarrow apex and broader flare coronally.

10/20/2009 kmw12 43

Use of pastes

Different pastes are used by some yetbut may leach in to periradiculer tissueresulting in chronic inflammation andtoxicity. As well pastes may getabsorbed due to porosity causing apicalleakage.

10/20/2009 kmw12 44

Studies on extrusion of several sealing material andG.P have shown that, in addition to the ill effect of

the material the symptoms are location related.Teeth with root apices in close proximity to sensory

nerves Eg. Inferior dentalanddtto maxillary sinus

can cause more pain and discomfort.All endodontic procedures of these teeth should be

done with utmost care.

10/20/2009 kmw12 45

Most extrusion cases are symptom less.In many others symptoms are transient. Evenin cases with prolonging discomfort best is towait and watch. Treatment if essential is

surgical.

10/20/2009 kmw12 46

Voids

• The GP will have to fill the entire canal preparation inall planes three dimensionally in a homogenous mass.Voids should be avoided. The funnel shaped canalpreparation allows flow. Both lateral cold compactionand vertical compaction of thermoplastic GP, canleave voids due to several reasons. Lack of skill andcare being the primary reasons.

10/20/2009 kmw12 47

Only a microfilm of sealer isacceptable. Though radiographs

show complete filling due toexcess sealer, unless lateral and

vertical compaction of GP isdone well, voids will remain,

causing micro leakage.10/20/2009 kmw12 48

Vertical fracture

Use of excess force during GPcompaction too may cause vertical

fracture.

10/20/2009 kmw12 49

Vertical fracture

It may happen during pin placementfor core buildup following

endodontic treatment, when excessforce is applied and when a tapered

pin or a posttiis placed.10/20/2009 kmw12 50

Vertical fractureA vertical fracture usually leaves no

room for treatment or recovery andextraction of the tooth becomes

inevitable

10/20/2009 kmw12 51

10.Coronal restoration

It is equally important to place a coronalrestoration that would prevent micro

leakage,between visits and

just after the obturation is completedZno+ Euginol TF is not at all welcome.

10/20/2009 kmw12 52

Placing Posts / Pins

If a post and core should be built there shouldnot be any void between the post and the GP

and the GP should be reduced in the canal –with a heated instrument only.

Cutting burs should not be used to cut theGP.

The GP that remains on the canal wall should

be removed with a GG bur.

10/20/2009 kmw12 53

Avoiding Problems

Proper assessment as said earlier, utmostcare and clinician’s dedication to prevent

problems is the best assurance againstmost the above problems.

10/20/2009 kmw12 54

However some problems cannot be avoidedand are unpredictable.

Eg. Micro leakage to and fro throughaccessory canals that appear at furcations of

the Maxillary and Mqandibular molars maynot be recognized even with good

magnification as they are only about twice thesize of Dentinal tubules

making the clinician helpless.

10/20/2009 kmw12 55