National medical university of LVIV department of therapeutic dentistry



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Reference literature


  1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev. ed.– New Yourk, 2009.– 249 p.

  2. Stephen Cohen, Richard C. Burns. Pathways of the pulp. Eighth edition.– Mosby, 2002.– 1031 p.

  3. Fan B, Wu M-K, Wesselink PR. Leakage along warm gutta-percha fillings in the apical canals of curved roots. Endod Dent Traumatol 2000;16:29-33.

  4. Glosson CR, Haller RH, Brent Dove S, del Rio CE. Comparison of root canal preparations using NiTihand, NiTi engine-driven and K-flex endodontic instruments. J Endod 1995;21:146-51.

  5. Molven O, Halse A, Grung B. Surgical management of endodontic failures: indications and treatment results. Int Dent J 1991;41:33-42.

  6. Seltzer and Bender’s. Dental pulp // Quintessence Publishing, 2002.

Practical lesson No 38
Theme: Filling of the root canals with partially hardening and hardening sealers and fillers.

Short description of theme
Seallers - hardening materials, which are used for filling of the empty spaces between the point and the root canal walls while the root canal obturation.

It is used:



  • for additional lateral root canals obturation;

  • to form the compact layer between the point and a root canal walls;

  • to isolate not straight spaces on the root canal walls.

The properties of the seallers should be as follows:

  • the high adhesion level to the root canal walls;

  • it should lead easily into the root canal;

  • provide full hermetisation of the basic root canal and delts;

  • be visible on X-ray film;

  • the low shrinkage after the hardening;

  • the small particles of sealler filler;

  • should not paint the tooth;

  • must possess bacteriostatic effect;

  • must have the low time hardening;

  • must be resistant to solubility;

  • must not irritate the periapical tissues;

  • in case of the retreatment provide the possibility to be solved by special solvents;

  • do not have the mutagenic and cariogenic features;

  • must have no influence on the immune system.

ZOE- high effective endodontic hermetic. They formed according to Rickert formula, and include next components:

  • ZnO – 42%;

  • Stabelith resin – 27%;

  • Bismuth subcarbonate – 15%;

  • BaS – 15%;

  • Borat Na waterfree – 1%;

  • Eugenol;

As supplements can be used : antiseptics, hormones and others.

„Endomethasone”, „Endobtur”, „Estesone” (Septodont), „Cariosan” (Spofa Dental).

Sealler which is based on the epoxide resins. This is sealler „paste-paste” or „powder-liquid” type which is hardening after the mixing in temperature 36ºC which is last 8-36 h. This type sealers: AH-26, AH-plus (Dentsply), “Diaket” (ESPE).

Seallers, which contain Ca(OH)2 can stimulate the mechanism of cementoblastes integration. As a result it can form the apical barier. The bone tissue revival is possible in case of this type sealler usage. Ca(OH)2 – white powder with 12,5 pH level.( it is very important, because this pH level possesses with antiseptic property. The modern materials: „Sealapex” (Kerr), „Apexit” (Vivadent), „Endocal” (Septodont)



Glassionomers.

This type of materials has a chemical adhesion to dentin that provides long and reliable root canal obturation. The glassionomer for the root canal obturation hardening time is 1,5- 3 h. It can be used in case of wall perforation or when the wall thickness is small.The most popular in this group is: „Ketac-Endo Apical” (ESPE), „Endition” (VOCO).

The sealler disadvantages:


  • cytotoxity that gets weaker while the hardening;

  • it can dissolve, that lead to bad obturation hermetcity and microleakage;

  • the sealler components while spreading in periapical tissues, can provoke the chemical and mechanical irritation;

  • do not hermetically sealedroot canal system obturation;

  • necessity of the fillers usage.



Control questions to|by| practical lesson


  1. What are the advantages and disadvantages of ZOE sealler usage?

  2. What is the advantage and disadvantage of glassionomer sealler using?

  3. What is the advantage and disadvantage of epoxyde resin sealler using?

  4. What is the advantage and disadvantage of use the sealer which contain Ca(OH)2?

  5. What is meant under the definition „sealler”?

  6. Mistakes and complications which can be in work with ZOE sealler.

  7. Mistakes and complications which can be in work with glassionomer sealler.

  8. Mistakes and complications which can be in work with epoxyde resin sealler.

  9. Mistakes and complications which can be in work with the sealer which contain Ca(OH)2.

  10. Indication and contraindication for a sealler use.

  11. Indication and contraindication for the ZOE sealler

  12. Indication and contraindication for the glassionomer sealler

  13. Indication and contraindication for the epoxyde resin sealler

  14. Indication and contraindication for the sealler which include Ca(OH)2.



Situation tasks and test control
1. Standard gutta-percha posts are used as the main post because they:

A. are long, cone-shaped and dissolved in the chloroform

B. penetrate easily into the narrow cursed canals

C. their diameter and form is similar to the diameter and form of the instruments for root canals


2. Standartizated gutta-percha points are used as master points because:

A. they are long, taped and can be dissolved in chloroform

B. can be easily adapted in curved root canals

C. have the same diameter and shape as root canals endodontic tools

D. they are hard,straight and can be adapted easily in the root canal
3. The main gutta-percha post must be closely inserted into the canal:

A. apical 1/3 length

B. in the 1/3 length

C. throughout the entire canal

D. all over the canal
4. The main compound for the majority root cements is:

A. epoxy resin

B. polyvynil resin

C. zinc-oxide-eugenol

D. precipitated silver
5. At present, the most commonly used root canal cement (sealer) is:

A. Rikert’s sealer

B. Vakha’s sealer

C. chloropercha

D. Grossman’s type sealers
6. Prior to gutta percha filling, the canal is prepared with due regard to its walls:

A. they are to be parallel lengthwise

B. they slightly converged to apical narrowing

C. they are the widest in the apical and mesial 1/3 length of the root

D. they extend to apical opening
7. Which of statements about gutta percha is true?

A. gutta-percha-based posts contain 20% of it

B. its molecular elastic properties improve the hermeticity of the canal filling

C. The use of gutta-percha alongwith chemical solved possesses the space stability


8. Which of the statements, concerning silver points is true?

A. The content of silver in them is approximately about 70%

B. Texture of their surface does not influence on the root canal adhesion

C. They prove to be the least toxic in endodontics

D. They can be exposed to corrosion, that possesses the cytotoxic affect
9. What statement about the silver points is true?

A. Silver points contain 70% of silver

B. Silver points corrosion can be cytotoxic

C. They are the least toxic materials in endodontics

D. The surface of pin does not effect on sealler adgesion
10. Free eugenol in the root canal sealer increases:

A. space stability

B. hardening time

C. cytotoxic effect

D. firmness
11. Paraformaldehyde-containing cements of root canals can be used in:

A. temporary pulpotomy

B. treatment of necrotic pulp

C. root canal filling


12. Sealers that contain paraformaldehyde can be used in:

A. temporary pulpotomy

B. pulpectomy

C. necrotizing pulp treatment

D. obturation

Reference literature


  1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev. ed.– New Yourk, 2009.– 249 p.

  2. Stephen Cohen, Richard C. Burns. Pathways of the pulp. Eighth edition.– Mosby, 2002.– 1031 p.

  3. Fan B, Wu M-K, Wesselink PR. Leakage along warm gutta-percha fillings in the apical canals of curved roots. Endod Dent Traumatol 2000;16:29-33.

  4. Glosson CR, Haller RH, Brent Dove S, del Rio CE. Comparison of root canal preparations using NiTihand, NiTi engine-driven and K-flex endodontic instruments. J Endod 1995;21:146-51.

  5. Molven O, Halse A, Grung B. Surgical management of endodontic failures: indications and treatment results. Int Dent J 1991;41:33-42.

  6. Seltzer and Bender’s. Dental pulp // Quintessence Publishing, 2002.

Practical lesson No 39
Theme: Methods of fillings of the root canals. Mistakes and complications during endodontic manipulations, their reasons and ways of removal.


Short description of a theme
Materials and Instruments for Root Canal Obturation.

The goal of obturation is to seal off the root canal and its ramifications from oral fluids and bacteria. Al­though there is no ideal filling material, gutta-percha and sealer cements have proved to be the materials of choice in contemporary endodontics because they ex­hibit minimal toxicity and tissue irritability when con­fined to the root canal system.



Gutta-percha.

Originating from special trees in Africa and South America, pure gutta-percha is considered to be an isomer of natural rubber known as trans-polyisoprene and is less elastic, more brittle, and harder than natural rubber. It can exist in both alpha and beta crystalline forms; these forms are interchangeable depending on the temperature of the material. The alpha form is the natural state, is less subject to shrinkage, and is often used in obturating systems that use thermoplasticized, or heat-softened, gutta-percha. The beta form, which is typically found in gutta-percha cones or points, is used in cold compaction techniques such as lateral con­densation. Gutta-percha cones or pellets used in vari­ous obturation techniques contain approximately 19% to 22% gutta-percha, 59% to 75% zinc oxide, and a se­ries of other additives, including waxes, coloring agents, antioxidants, and metallic salts.

The gutta-percha cone or pellet, in conjunction with a root canal sealer, must be compacted in the canal to conform to the prepared root canal system. Gutta-per­cha cones are available in standardized and nonstandardized forms. The standardized forms conform to the same dimensions and uniformity as those used for endodontic files; thus, a No. 40 gutta-percha cone should reasonably fit a canal that has been properly pre­pared with a No. 40 file. The nonstandardized forms, classified as medium, medium-fine, or fine-fine, have greater tapers than standardized cones and are often used in techniques that involve vertical compaction of heat-softened gutta-percha or filling of the coronal two thirds of a canal after a standardized cone has been com­pacted in the apical third.

A couple of obturating techniques and instruments can be used to compact gutta-percha into the root canal system. In lateral condensation, a long (17- to 30-mm), tapered, metallic instrument with a pointed tip known as a spreader is used to compact the gutta-percha cones and sealer laterally against the canal walls. Spread­ers are available in both hand and finger forms and are made of stainless steel or nickel-titanium for greater flexibility. Root canal pluggers are used in the vertical condensation method. These are long, slightly tapered, metallic instruments with flattened or blunt tips. Avail­able in both hand and finger types, pluggers are de­signed to compact gutta-percha and sealer vertically after the gutta-percha has been thermosoftened with a hearing device.



Root canal sealers.

Root canal sealers are used to cement the gutta-percha in place, to fill voids and the intricate ramifications of the canal system, and to lubricate the cones during lat­eral compaction of the relatively nonrigid gutta-percha points. They should be biocompatible with and well tolerated by periradicular tissues.

The most commonly used sealers are zinc oxide-eugenol (ZOE) and calcium hydroxide-based cements because of their good working properties, sealability, biocompatibility, and ease of removal. Resin-, glass-ionomer-, and silicone-based sealers are also available but are more technique sensitive, difficult to remove, and have variable sealing properties.

When mixed into a thick, creamy consistency, sealers are placed inside the root canal via paper points or a lentulo spiral, or are deposited in a light layer through the counter-clockwise rotation of an en­dodontic file. Examples of endodontic sealers include Roth's 801 (ZOE-based, Roth Drug), Pulp Canal Sealer (ZOE-based, Kerr Analytic), Sealapex (calcium hydroxide-based, Kerr Analytic), ThermaSeal Plus (resin-based, Dentsply), and Ketac Endo (glass ionomer-based, 3M ESPE).

Adjunct Materials

Calcium hydroxide

Calcium hydroxide has been used in dentistry for many years, both as an intracanal medication and as a pulp-capping agent. It is available in a variety of forms, ranging from pure chemical grade to proprietary com­pounds (CalaseptJS Dental; Tempcanal, Pulpdent). For intracanal use, calcium hydroxide has been proven to be antibacterial and may aid in the dissolution of necrotic pulp tissue. Its high pH is responsible for the destruction of bacterial cell membranes and protein structures. When pulps are exposed during routine cavity preparation, a pulp-capping agent such as Dycal (calcium hydroxide [Dentsply]) or mineral trioxide ag­gregate (discussed later in this section) can be placed as a "bandage" over the bleeding tissue in an attempt to promote dentinal bridge formation over time, thus preserving the vitality of the pulp.

Mineral trioxide aggregate.

Mineral trioxide aggregate (MTA) (ProRoot, Dentsply) is one of the newest and most promising materials to enter the realm of endodontics in many vears. This root canal repair material is a grayish powder consist­ing of fine, hydrophilic particles that set in the pres­ence of moisture. The hydration of the pow­der, composed of tricalcium silicate, tricalcium phosphate, tricalcium oxide, and others, creates a col­loidal gel that solidifies to form a strong impermeable barrier. The material sets within 3 to 4 hours and has a working time of 5 minutes; it has been shown to be biocompatible and its seal is superior to that of amal­gam. Although the material is somewhat costly and dif­ficult to work with, primarily due to its naturally sandy consistency when hydrated, the indications for its use include clinical situations that often have no other vi­able options, such as perforation repair. Indications for ProRoot include pulp capping, internal repair of perfo­rations (noncommunicative), apexification, and root-end filling in endodontic surgery.



gutta-percha. The purified coagulated exiidate from the mazer wood tree. It is a high-molecular-weight stereoisomer of polyisoprenc. Since the 1950s, ma­terial compounded in the United States for "gutta-percha" points has been made from balata, a nearly identical latex from a special tree in South America.

Irrigants. Liquids used to dissolve and flush out root canal debris; examples include sodium hypochlorite, saline, and hydrogen peroxide.

Obturation. The complete filling and closing of a cleaned and shaped root canal with a root canal sealer and core filling material.

Control questions to|by| practical lesson


  1. What is the goal of root canal obturation?

  2. What types of endodontic posts for root canal obturatyion do you know?

  3. Describe the features of gutta-percha cones.

  4. What are the most commonly used endodontic sealers?

  5. What techiques of root canal filling do you know?

  6. Describe root canal filling technique with central gutta-percha point.

  7. Describe root canal filling technique with lateral compaction of gutta-percha points.


Situation tasks and test control
1. Which of the assertions as to the silver points is true (correct)?

A. Silver content in them is equal to 70%

B. Texture of their surface does not influence on the sealer adhesion

C. They prove to be the least toxic in endodontics

D. They can be exposed to corrosion that has cytotoxic affect
2. Standard gutta-percha post are used as the basic posts, because they are:

A. long, cone-shaped and thermoplastic

B. they can easily penetrate into the narrow, curved, cursed canals

C. of the same diameter and cone shaping with instruments used for root canals

D. tough, strong and are easily interested into the canal
3. In case the X-ray shows that the standard gutta-percha point is a little bit shorter (up to 0,5 mm), then the dentist can:

A. select the most suitable point among the rest of the same size

B. widen the canal with a help of K-file with a proper size

C. use the lubricant for inserting the post with the apical effort

D. use it, taking into account the necessity in filling a gap with a sealer
4. Which of the mentioned instruments and materials proved to be unnecessary for the lateral condensation?

A. Sealers

B. Standard gutta percha post

C. Spreaders

D. Pluggers

5. How is the sealer introduced in lateral condensation?

A. By a canal filler with 200 rotations per minute that completely fills the canal

B. A small amount of sealer is introduced into the canal with a help of canal filler (200 rotations per minute)

C. A small amount of siler is introduced into the canal with a help of manual canal filler

D. Method of introduction and amount of sealer are not important
6. Working part of instruments for root canal filling. Which of the following instruments is revolving condensor?



7. Which of the enumerated instruments and materials are unnecessary for filling with thermofil?

A. Sealer

B. Spreader – heat-carrier

C. Carrier of gutta-percha – thermofil

D. Over for gutta-percha heating
8. The best facilities for gutta-percha sterilization are the use of:

A. 90% alcohol

B. 3% hydrogen peroxide

C. 70% alcohol

D. 5,25% sodium hypochloride
9. For gutta-percha sterilization it is better to use:

A. 90% alcohol

B. 3% H2O2

C. 70% alcogol

D. 5,25% NaOCl
10. The ideal filling material must:

A. possess a sufficient shrinkage for canal filling

B. readily fill the canal laterally and apically, adjoining its walls

C. resolve under the influence of the tissue fluids, without causing irritation

D. possess spongy surface for supporting the tissue growth
11. The ideal canal cement used with a semisolid point:

A. fills the roughness between the filling and canal walls

B. as a rule, irritates the periapical tissues

C. is radiopaque an applying, but not in final hardening



D. influences insignificantly on the final result of treatment

Reference literature


  1. Clincal endodontics: a textbook /Leif Tronstad.– 3rd rev. ed.– New Yourk, 2009.– 249 p.

  2. Stephen Cohen, Richard C. Burns. Pathways of the pulp. Eighth edition.– Mosby, 2002.– 1031 p.

  3. Fan B, Wu M-K, Wesselink PR. Leakage along warm gutta-percha fillings in the apical canals of curved roots. Endod Dent Traumatol 2000;16:29-33.

  4. Glosson CR, Haller RH, Brent Dove S, del Rio CE. Comparison of root canal preparations using NiTihand, NiTi engine-driven and K-flex endodontic instruments. J Endod 1995;21:146-51.

  5. Molven O, Halse A, Grung B. Surgical management of endodontic failures: indications and treatment results. Int Dent J 1991;41:33-42.

  6. Seltzer and Bender’s. Dental pulp // Quintessence Publishing, 2002.

Practical lesson No 40
Theme: Module control.




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