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11

Diala Derbashi

Rada Haddadin

…

Afnan Ali

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د+ما تقلقوا من عدد الصفحات في كتير صوريعطيكم العافية , الشيت شامل الساليدات + ترتيب الشيت مختلف في بعض االشياء عن الريكور

-Remainder: the main cause of pulp periapical diseases is bacteria

-Aims of endodontic treatment:

•To remove all micro-organisms from the root canal system

• To remove all canal contents (organic or otherwise) that

may lead to growth of micro-organisms or the breakdown of

toxic products and their release into the periapical tissues

• To prepare the canal for its disinfection and to develop a

shape that permits a simple and effective root canal filling to

be placed

• To prevent micro-organisms from entering the tooth again

and re-establishing infection in the root canal system as this

causes apical periodontitis

-Is it possible to do RCT in one visit especially

when you are treating an infected canal? NO

-when bacteria enters the canal , it becomes

infected →then necrosis and pulpless happens

-after bacteria enters the canal, it can also

enter the dentine

-as you see in the figure:

*there is 81% of bacteria in zone A

*in zone B+C , bacteria is also exist

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-The results below were shown after doing one-visit endodontic

treatment for a certain number of teeth then they extracted them and

checked the microbial status of the teeth by looking at their histological

sections

Notice that the dentinal

tubules are permeable so

microbes can hide and

exist inside them

Notice the complexity of root

canal system ; it has fins

,transverse anastomoses ,lateral

canals ,accessory canals ,etc →

all of them can have bacteria

and microorganisms inside

-Notice that most of the microbes are found in the isthmus and lateral canals

because these two areas are inaccessible to endodontic files and irrigant

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-these histological sections show you that there are microbes in isthmus

and fins after single Vs two visit treatment (and of course two visits is

better)

the yellow area is dentine

-A classical study (which was made by Bystrom ,Sundqvist ,Sjogren)

shows that even after using sodium hypochlorite , we only get 50% of the

canals free of bacteria but when using EDTA(chelating agent) + NaOCl it

goes up to 70% (there is still 30% of the canals that are not bacteria free)

Single visit treatment Two visit treatment

- So, irrigants doesn't really eliminate all of the bacteria from root canal system

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-Another classical study was made showing the microbiological analysis

of teeth with failed endodontic treatment and the outcome of

conservative re-treatment

Notice that when 12% of teeth had microbes present at time of root

filling , only 33% of these cases healed overtime. But when 88% had no

microbes present at time of root filling , 80% of cases healed over time

→ this means that when we don't have bacteria inside the canals , we

will have more predictable outcome.

-The study below shows the influence of infection at the time of root filling

on the outcome of endodontic treatment of teeth with apical periodontitis.

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*when there was a positive culture (which means that microbes are

present at the time of root canal filling (RCF) ) ,the healing (successful

outcome) was for 68% of cases

*when there was a negative culture at the time of RCF ,the healing was

for 94% of cases

*Notice that the result of this study support what we saw in the

previous studies.

-All the previous studies support and emphasize: (Discussion)

1) Emphasises the need to eliminate bacteria from canals prior to placing

the RCF.

2) This cannot be reliably achieved with one-visit treatment procedure.

3) Demonstrate – it is not possible to remove all organisms from root

canals without the support of inter-appointment anti-microbial dressings.

-Observation:

Bacterial numbers increased in the empty canals between appointments

(that is why we should place inter-appointment medicaments inside the

canal)

Leaving a space inside the canal →give opportunity for the bacteria to

increase in number →so the aim of endodontic treatment is not achieved

-Conclusion:

An inter-appointment antibacterial dressing is necessary to predictably

achieve canals that are free of bacteria (actually it will not be completely

free from bacteria but the more you reduce its number , the better the

outcome is )

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-When treating infected canals , use two or more visits AND an

intracanal medicament in order to:

(1) increase predictability of periapical healing by destroying more

bacteria and by changing the environment within the canal

(2) reduce post-operative pain and external inflammatory root resorption

(external inflammatory resorption means :that the root get resorbed due

to inflammation (it occurs with the resorption of bone) )

-One visit is enough

-suggested arguments for 'one visit':

=>canals not infected

=>no apical periodontitis

-The canals are not considered infected in these cases:

a) the pulp is still vital

b) pulpitis

c) Elective endodontics

-Elective endodontics : it is doing an endodontic treatment for a normal

pulp in specific cases ,such as: when I need retention of a restoration in

case of loss in tooth structure all around and the tooth doesn’t need

endodontic treatment but I should do in order to place a post inside the

canal ( treating an normal pulp just for a restorative reasons)

From the internet: A post and core crown is a type of dental restoration required where there is

an inadequate amount of sound tooth tissue remaining to retain a conventional crown. A post is

cemented into a prepared root canal, which retains a core restoration, which retains the

final crown

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-What is the diagnosis of this case?

Answer: acute irreversible pulpitis and acute apical periodontitis (notice

the radiolucency)

-removing the pulp implies severing the nerve fibers, this will invoke

periapical inflammation (even when removing a normal pulp)

This is the reason why some patients still feel pain when they apply a

force on the tooth even after doing a RCT for it

نفس مبدأ انه لما تنجرح راح يصير في Inflammation مكان الجرح

-The neural response to removing the pulp is a derangement of the

plexus of nerves around the apical third of the root:

disorganized axon "sprouting and branching" (due to the inflammation that will happen)

some features are similar to neuromas (normal neuromas)

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Notice the sprouting

and branching of

nerves

Notice the sprouting and branching→ which result in amplification of the response

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-An experiment that has done in cats (by Holland) shows that the

inflammatory and neural changes continue for at least one year after

RCT ( it may be longer in humans).

This can explain the different sensation/discomfort/awareness repeated

by some patients after endodontic treatment (the solution for these

patients in order not to feel pain when apply a force on the tooth: simply

advise them to stop applying that force on the tooth in order not to make

trauma in the nerve again; just let it heal).

-The neural and inflammatory responses can be greatly reduced (but not totally

eliminated) by using corticosteroids ( it has an anti-inflammatory action).

→ Holland used corticosteroids systemically in cats (injection).

→ In humans: we can use intracanal corticosteroids (it is not logic to

give the patient an injection to reduce the inflammation of a certain

tooth. Instead, we place it locally inside the canals.

- using corticosteroids →neural and inflammatory responses reduce

→chances of having a post-operative pain after irreversible pulpitis and

elective endodontics reduce.

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Notice that after using dexamethasone ,the chances of having a post-

operative pain are significantly reduced .

الدكتورة ما شرحت الرسمة الي فوق بس حكت هاي الجملة عنها

-The neural response due to removing the pulp differs from natural

amputation (e.g: pulp necrosis ,deciduous exfoliation) Holland-1995

{Explanation: in case of pulp necrosis or when the deciduous teeth are

fallen due to physiological process→ the previous response

(derangement of plexus ,branching ,….) will not happen → instead, the

nerves are degenerated (a physiological process) }.

-In case of natural amputation, healing occurs gradually and nerves grow

out to innervate new target tissue (e.g: gingiva, bone, periodontal

ligament).

-When treating pulpitis or electively removing normal pulps, use two or

more visits and an intracanal medicament in order to:

1) reduce periapical inflammation

2) reduce nerve sprouting

3) reduce pain

4) ensure no bacteria remain in the root canal system (actually I am not

worried about bacteria because it is a sub-infected case)

المذكورة فوق وحدة لكن يفضل اكتر بسبب النقاط بهاي الحاالت انا ممكن اخلص الشغل بزيارة

-Between appointments / visits: use an intracanal medicament (the canal

should not be left empty) + place a temporary restoration.

So we should do temporisation of the tooth.

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-Temporisation during endodontics includes:

• temporary coronal restoration (coronal seal)

– interim

Temporary

• temporary root canal filling (by placing the intracanal medicament)

-Why do we use intracanal medicaments?

1) anti-bacterial action

*reduce the number of residual bacteria in canals and inaccessible

area (such as: tubules, fins) that are protected from chemomechanical

preparation, immune host response and systemic antibiotic

* prevent contamination between visits

* anti-bacterial action in periapical region

* anti-bacterial action in periodontal tissue

2) prevent or reduce pain (especially when using a medicament that

containing corticosteroids)

3) reduce periapical inflammation

4) induce apical hard tissue barrier formation (this is important in case

of having an open apex or any perforation along the canal)

5) help eliminate apical exudate (apical exudate is a sign of continuing

inflammation and infection, so by using medicaments you eliminate it)

6) stimulate periapical tissue repair

Temporisation During Endodontic Treatment

Temporisation of root canal

Why? Because the

medicament spreads into

dentine (diffusible)

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7) prevent or inhibit inflammatory resorption

-Endodontic Medicaments Choices:

• corticosteroid / antibiotic based medicaments (CS/Ab)

e.g: Ledermix paste, Odontopaste

• calcium hydroxide medicaments ( Ca(OH)2 )

e.g: Calasept Plus paste, PulpDent

• 50:50 mixture { CS/Ab + Ca(OH)2 }

there is no scientific evidence of this

-Which medicament do we use? You should select the appropriate

type of medicaments according to the problem

-Major functions and choices of medicaments:

1. anti-inflammatory action

*the anti-inflammatory action is needed in cases of:

-acute irreversible pulpitis, acute apical periodontitis

*ledermix paste, odontopaste

2. anti-bacterial action

*the anti-bacterial action is needed in cases of:

-pulpless or necrotic pulp

-root-filled + infected root canals (a previously endodontic treated tooth)

*calcium hydroxide

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3. stimulate hard tissue repair

*we need it in case of having an open apex (we should do

apexification)

*calcium hydroxide

• Ledermix paste

• Odontopaste

• Septomixine Forte paste

• Pulpomixine paste

Ledermix Paste

*it is the best medicament to use in case of trauma (trauma causes

inflammation)

*developed in 1960 ( Prof. André Schroeder)

*commercially available since 1962

*52 years of research and clinical use! يستخدموه لفوائده( رجعوا )النه زمان كانوا ضد استخدامه بس بعدين

-The components of Ledermix:

1) triamcinolone – 1% → corticosteroid part (CS)

2) demeclocycline (tetracycline) – 2% → antibiotic part (AB)

In a water soluble paste of:{ Not mentioned by doctor }

• Triethanolamine NF

• Calcium chloride USP

• Zinc oxide

• Sodium sulphite (anhydrous)

Corticosteroid / Antibiotic medicaments

the most popular

are not used anymore because they are carcinogenic

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• Polyethylene glycol 4,000 USP

• Distilled water

-any medicament in the canal to be effective it should diffuses into the

dentinal tubules reaching the periapical and peri-radicular tissues.

A good thing about Ledermix is having a very rapid release in the first

day → which is important in case that the patient cannot sleep because

of his tooth pain so using Ledermix will reduce post-operative pain

immediately at the same day.

Notice that Ledermix has very rapid release initially then slow and

steady release that last up to 6 weeks (so I shouldn't leave it in the canals

more than 6 weeks).

-Abbott confirmed that the triamcinolone (CS) part of Ledermix has

been detected in peri-radicular areas which means that it is effective

around the root and sufficient for anti-inflammation action.

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-Ledermix paste can be used in endodontic therapy for its:

• anti-inflammatory action (the mainly usage) (by the help of CS part)

- reduces and prevents pain, reduces nerve sprouting

• anti-bacterial action (limited; I cannot rely on ledermix as

anti-bacterial action) (by the help of AB part)

- helps to reduce inflammation, starts the healing process

• inhibition of clastic cells (by the help of AB(tetracycline) part)

-reduces resorption of tooth and bone (by inhibiting the clast cells)

• inhibition of PMN (polymorphonuclear) neutrophil collagenase

- reduces tissue destruction

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Odontopaste (Australian made product)

-the main disadvantage of ledermix is: if the access cavity isn't cleaned

well from ledermix then the tooth exposed to light (especially ant teeth),

discoloration of tooth will happen.

and it is an important thing to keep in mind especially when using

ledermix in anterior teeth. So they discovered odontopaste to overcome

this disadvantage .

-It is similar to ledermix paste

but AB is clindamycin

it contains 1-2% Ca(OH)2 - has varied (e.g. 5% originally)

-Provides an alternative for some cases:

e.g. If an infection is not responding (resistant infection)

e.g. If discoloration is a concern (it is good for using in anterior teeth)

*The most popular intracanal medicaments used

*calcium hydroxide is powder originally but we mix it with another

substance by using a vehicle in order to improve its flow (because it is

difficult to put a powder in the canals) and to facilitate its dissociation.

*Chemical properties:

• white odourless powder

• high pH (12.5-12.8) → we use Ca(OH)2 because its high pH that

comes from the hydroxyl ions which is important for the

anti-bacterial action

Calcium hydroxide

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• low solubility in water

• dissociates into Ca+2 and OH-

• vehicle – enhance radiopacity, consistency, flow and antimicrobial

activity

• vehicle type (aqueous, viscous and oily) determines:

a) rate of ionic dissolution (aqueous have higher rate than

viscous)

b) solubility in tissue fluids ( high solubility→ high rate of

dissolution)

c) longevity of desired effects (it will be longer when using

viscous than aqueous)

-in some cases like apexification for example when I need to put Ca(OH)2

in the canals for 3 months, I should use a viscous vehicle BUT if I need a

very quick result and a rapid dissociation, I should use the aqueous.

*Commercial preparation of Ca(OH)2 :

1) Saline base (aqueous vehicle)

Calasept Plus

2) Methyl-cellulose base ( a little bit more viscous)

Pulpdent paste

3) Powder - to mix with various liquids (such as: saline ,local anesthesia)

4) Impregnated on GP points (not effective)

Roeko

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*This figure shows where the action of calcium hydroxide occurs

1→ inside the canal

2→ in periapical tissue

3→ inflammatory root resorption (apical and lateral)

4→ root fracture (I need to put a calcific barrier)

5→ apical resorption

*Calcium hydroxide is the most widely used endodontic medicament

throughout the world (WHY?)

1) mainly because of its anti-bacterial activity →which is acquired

from its high pH → that comes from the release of hydroxyl ion OH- →

hydroxyl ion is a free radicle that bacterial enzymes of cytoplasmic

membrane + act as a physical barrier

2) stimulate hard tissue formation (calcific barrier)

3) helps dissolve necrotic tissue (improve the tissue solubility of NaOCl)

4) inhibits inflammatory tooth resorption

5) detoxifies bacterial endotoxin (LPS)

1 2 5 4 3

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*LPS causes inflammation and bone resorption by stimulation

macrophages to release cytokines ( e.g: TNF/ IL-1,6,8)

*LPS was not inactivated by biomechanical preparation and irrigation

with: saline, chlorhexidine (2%) , NaOCl (1% , 20.5% , 5% )

but LPS was inactivated by calcium hydroxide.

*efficacy of calcium hydroxide depends on release and diffusion of

hydroxyl ions through dentine.

→this result in production of pH gradient (because the pH in the canals

isn't equal the pH outside)

→ notice that the pH in the canal is the highest. As you go away from

the canal, the pH will become less.

*Release and diffusion of hydroxyl ions through dentine depends on:

• Period of exposure (if you put calcium hydroxide for one day, the

dentine will not have any OH- ion or any change in pH →so

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calcium hydroxide should be put in the canal for enough period of time)

• Dentine permeability

(the dentine is more permeable and tubules is larger in

coronal(cervical)part than apical part) , (the inner dentine is more

permeable than the outer dentine which contributes in having a pH

gradient)

• Vehicle type (viscous / aqueous)

• Smear layer (if the smear layer is still exist, it will interfere the

diffusion)

• Cementum layer (if the cementum layer is intact, the OH- ion will

not reach the peri-radicular tissue)

• Dentine buffering capacity? (it was thought that the dentine can

buffer the alkaline but actually it isn't proven scientifically )

• Level of placement (for example, if I put calcium hydroxide in the

upper area then the apical dentine will not have any pH change)

• Method of placement

• Retreatment procedure (if I want to make a retreatment of a

previously treated tooth and gutta percha is still there, the OH- ion

will not be able to diffuse)

*Limitations and potential problems with calcium hydroxide:

1. toxicity (initial and long-term)→ if calcium hydroxide is pushed

outside the canal, the patient will have a painful and inflammatory

reaction to it – it is tissue toxic)

2. increased replacement resorption (especially when using it in case of trauma)

(remember that ledermix is the best medicament used in case of trauma)

(replacement resorption means that the root which is resorbed will be replaced by bone)

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3. increased ankylosis ( pathological fusion between alveolar bone and

the cementum of tooth – there is no periodontal ligament space)

(when using calcium hydroxide in case of trauma, it will increase the

ankylosis BUT Ledermix will not)

4. may promote inflammatory resorption

5. may affect dentine mechanical properties (long term)

This is not really confirmed when using calcium hydroxide in short-term period

*For how long should medicaments be used?

• Absolute MINIMUM time: 2 weeks

→Since inflammation takes 10-14 days to resolve

• Most BENEFICAL and MAXIMUM times:

-Ledermix paste

4 →6 weeks (because after 6 weeks, it will not be therapeutic anymore)

-Calcium hydroxide

3 - 4 weeks →6 months (depends on the type of vehicle used)

*this figure shows the pH changes in root dentine:

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Notice that the pH in inner area is higher

The highest pH (therapeutic level) for each area will be reached after 21 days

*look at the figure below:

Notice that after (3-4) weeks, calcium hydroxide will reach its

therapeutic level (highest pH).

According to the vehicle type used, I will decide the time needed for

calcium hydroxide to be left in the canals.

*Application of medicaments:

1. spiral filler

-it is spiral in shape (زي الزنبرك) , used in the slow speed handpiece in

an 'in and out' motion

-Preferred: most effective & easiest method

-ONLY if the canal has been enlarged

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2. hand file

-it resembles putting the sealer in the canal using endo files

-if canal has NOT been enlarged or prepared

→Not advised applications:

• Injection… because you may extrude the medicaments which

could be a tissue toxic, no control, over-extension likely.

• Paper point… because it is very soft, break down, periapical irritant.

*How to use spiral root filler?

-it is used in the slow speed handpiece then put inside the canal(it

should not bind to the walls)

- we should insert it (3-4)mm shorter than the working length in

'in and out' motion many times

-you should repeat this procedure (2-3) times then the medicament will

be float

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*The functions of temporary coronal restoration:

• prevent bacterial ingress during treatment (between appointment)

• prevent bacteria ingress after treatment (until definitive restoration

is placed)

• provide a sound base for rubber dam placement (effective control

for moisture and leakage)

• protect against tooth fracture during treatment (it holds the tooth

altogether during treatment especially when the walls of the tooth

is missing)

• provide a stable reference point (which is important in determining

the working length)

• provide aesthetics where required

*The two considerations of temporary coronal restoration:

1. restoration of the tooth (interim restoration)

2. restoration of the access cavity (temporary restoration)

Temporisation of the crown

We have to remove the

amalgam restoration and the

cause of the problem. Then

we have to temporize the

crown.

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-it lasts for a longer period of time than temporary restoration.

- interim restoration replaces all the walls that are missed after

removing a previous restoration or caries.

-done by using glass ionomer (ketac silver / ketac fil (tooth-colored) )

with or without using stainless steel orthodontic bands.

-ketac silver contains silver so it can withstand the mechanical bite

forces and because of that we use it for posterior teeth.

*must follow the manufacturer's instructions:

~ use dentine conditioner (in order to remove the smear layer and to

have a better retention) (it is different than acid etching)

• Retention: little difference

• Sealing: more reliable if conditioned

~ use resin cover (ketac glaze or bond) after placing the glass ionomer

while setting (we use it to cover the restoration- not the dentine- for

moisture control)

-notice the temporary filling (white

material) that is put in order to

replace the access cavity

-we don't use glass ionomer inside

the canals because it will be very

hard to re-access the tooth

- we use a material that is easily

removed in order to replace the pulp

chamber

-notice the silver material (glass

ionomer)

-GIC→ glass ionomer cement

Not mentioned by doctor

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*ketac silver is preferred wherever possible because:

• color contrast helps removal

can conserve more tooth structure

• stronger material - less brittle (because it contains silver) (it can

withstands high occlusal forces)

especially during lateral access cavity preparation

• less sensitive to moisture loss (saliva, blood)→ this is important in

cases of having deep margins

during setting ,, later when isolated with rubber dam

*look at the pictures below:

1→ notice the temporary filling

2→ notice the stainless steel band (it is not a matrix band; it is a permanent

band that always exists around the tooth) which protects the tooth from flection

and fracture

3→ notice the ketac fil which is a tooth colored glass ionomer (for

anterior teeth)

4→ notice the ketac silver (for posterior teeth)

1 4 3 2

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*ketac fil is used when aesthetic restoration required (in anterior teeth).

ketac silver isn't acceptable aesthetically for the usage in anterior teeth,

instead we use ketac fil.

*in case of tooth fracture, it is very hard to restore the tooth by putting a

filling (it will not stick with the tooth)

*Options after post/crown removed?

1) cotton wool (CW) / cavit: deep in post hole

(using the internal of canals for retention of the temporary crown)

-temporary post/crown with IRM or temporary cement {from slides}

temp. crown→ temp. post→ cavit→ CW→ dressing :الترتيب من برا لجوا

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-I cannot place the temporary post directly into the canal, instead I have

to protect the canal by putting a small cotton wool and cavit (temporary

filling) inside the canal then I can do cementation of temporary post and

crown

-Why I should place cotton and cavit? Because if the crown was fallen,

the root canal would be protected

2) CW/cavit in pulp chamber

-then place a GIC over exposed dentine (over the cavit) AND a

temporary overlay denture (removable denture)

3) CW/cavit in pulp chamber

-then place a temporary composite bridge bonded to root and to the

adjacent teeth

اجوا لبرالترتيب من : dressing→ CW→ cavit → GI →denture

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-we use both cavit and IRM (intermediate restoration material)→ double

seal

-Cavit is a calcium sulphate based material. It is also sense upon

contacting moisture

-components of cavit: {not mentioned by doctor}

Calcium sulphate

Zinc oxide

Glycol acetate

Polyvinyl acetate

Polyvinyl chloride acetate

Triethanolamine

Red pigment

-IRM is a reinforced zinc oxide eugenol

-after I place the interim

restoration, in the next

appointment I will drill through

this interim (so now I have

interim replacing the walls +

access cavity) then I prepare the

canals and take the working

length. After that, I should

temporise the access cavity

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-cotton wool must be sterile and condensed inside very well (because

any thread of cotton that is not condensed may be considered as a

pathway for the bacteria to enter the root canals

- low wear resistance means it cannot withstand the occlusal forces

-IRM prevents bacterial penetration because it contains eugenol which is

an anti-bacterial material.

-have a high wear resistance so it protects the cavit.

-have a low solubility BUT it cannot prevent the moisture penetration

alone.

*Why I should use both cavit and IRM together?

to use the advantages and to overcome the disadvantages of the

materials available

(+)→advantages

(-) →disadvantages

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*Eight essential steps to reduce the endodontic microbial flora:

1. Identify and remove the cause

2. Aseptic procedures

3. Mechanical instrumentation

4. Anti-bacterial irrigants

5. Intracanal medicaments

6. Interim & temporary restorations

7. Root canal filling

8. Coronal restoration

→ so we conclude that intracanal medicaments + interim and temporary

restoration are important to reduce bacteria and prevent it from entering

the canals during treatment

يا دفعة معلش

-finally, I end up having the

access cavity filled with

different materials which are

easily removed