Introduction:
The ultimate goal of root canal therapy is to conquer the complex root canal system by perfect obturation. The primary objectives of operative endodontics are total debridement of the pulpal space, development of a fluid–tight seal at the apical foramen and total obturation of the root canal. Earlier, root canals have been reported to be filled with Amalgam, Asbestos, Balsam, Bamboo, Cement, Copper, Gold Foil, Iron, Lead, OxyChloride of Zinc, Paraffin, Pastes, Plaster of Paris, Resin, Rubber, Silverpoints, Tin foil etc., Among all these materials tried, none of them met the requirements of an ideal obturating material.
Even after a three dimensional obturation of the system, coronal restoration may fail to provide a perfect seal and may permit microorganism & their toxins along the canal walls to their periapical tissue, leading to the failure of the treatment. So the quality of the coronal seal should be adequate to prevent micro leakage in to the canal space.Thus the concept of double seal came . Lack of satisfactory temporary restoration during endodontic therapy ranked second amongst the contributing factors in continuing pain after commencement of treatment.
Over the years various materials referred to as ‘Intra-orifice barriers’ have been sought by investigators to prevent coronal micro leakage & help produce a secondary seal for obturated canal. Thus along with time many sealing material for coronal sealing was tested. This also implies that an adequate coronal filling or restoration be placed to prevent oral bacterial microleakage. It has been shown that endodontic treatment success is dependent both on the quality of the obturation and the final restoration.1
Definition:
A DOUBLE seal consisting of gutta percha underneath material such as temporary cement ; used to close the coronal opening in a tooth during endodontic treatment. A DOUBLE seal consisting of gutta percha underneath material such as temporary cement ; used to close the coronal opening in a tooth during endodontic treatment.
• Many materials can be used to achieve some of these goals for effective inter-
appointment temporization. It is essential to have adequate knowledge of temporization techniques and material properties in order to satisfy a wide variety of clinical requirements such as time , occlusal load and wear ,complexity of access and absence of tooth structure.
Coronal 3-4 mm should be left for the placement of this double seal.
An inlay may cap none, or may cap all but one cusp.
Sturdevant’s 4th ed. page579
Inlays may be used as single-tooth restorations for proximo-occlusal or gingival lesions with minimal to moderate extensions
Shillingburg page 1
An inlay may be defined as a restoration which has been constructed out of mouth from gold, porcelain, or other material & then cemented into the prepared cavity of a tooth.
William McGehee pg410
introduction, history of rotary instruments in endodontics, classification, properties of NiTi, generations and design features, rotary file systems available
Smear layer is a controversial topic in the field of operative dentistry and endodontics. This presentation includes composition, concepts, structure, advantages, disadvantages, and removal methods of smear layer.
An inlay may cap none, or may cap all but one cusp.
Sturdevant’s 4th ed. page579
Inlays may be used as single-tooth restorations for proximo-occlusal or gingival lesions with minimal to moderate extensions
Shillingburg page 1
An inlay may be defined as a restoration which has been constructed out of mouth from gold, porcelain, or other material & then cemented into the prepared cavity of a tooth.
William McGehee pg410
introduction, history of rotary instruments in endodontics, classification, properties of NiTi, generations and design features, rotary file systems available
Smear layer is a controversial topic in the field of operative dentistry and endodontics. This presentation includes composition, concepts, structure, advantages, disadvantages, and removal methods of smear layer.
Post endodontic restoration /certified fixed orthodontic courses by Indian de...Indian dental academy
Welcome to Indian Dental Academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
This presentation is all about restoration of endodontically treated teeth, prefabricated post and core, cast post and core, direct and indirect technique.
As an intracanal medicament
Definition
Clinical application
Mechanism of action
Vehicles
Placement of Calcium hydroxide paste
Dentin and Calcium hydroxide
Effect of Calcium hydroxide on clinical outcome
Calcium hydroxide and Chlorhexidine
Calcium hydroxide and Sodium Hypochlorite
Removal of Calcium hydroxide from the canal
When to replace Calcium hydroxide dressing?
Calcium hydroxide and CO2
Toxicity
As a Root canal Sealer
Clinical significance
Classification
Composition
Properties
Leakage
Solubility
- In tissue fluids
- In chemical solvent
Biocompatibility
Antimicrobial
Toxicity
Conclusion
References
Techniques of direct composite restorationMrinaliniDr
Techniques of the direct composite restoration. Includes different instruments, matrix system, wedges, bevel, etching, bonding, and placement of composite along with finishing and polishing and clinical management
dental Monoblock obturation technique or concept in endodonticsAhmed Ali
dental Monoblock obturation technique or concept in endodontics which are classified into primary ,secondary & tertiary based upon resin , now the bioceramics
Post endodontic restoration /certified fixed orthodontic courses by Indian de...Indian dental academy
Welcome to Indian Dental Academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
This presentation is all about restoration of endodontically treated teeth, prefabricated post and core, cast post and core, direct and indirect technique.
As an intracanal medicament
Definition
Clinical application
Mechanism of action
Vehicles
Placement of Calcium hydroxide paste
Dentin and Calcium hydroxide
Effect of Calcium hydroxide on clinical outcome
Calcium hydroxide and Chlorhexidine
Calcium hydroxide and Sodium Hypochlorite
Removal of Calcium hydroxide from the canal
When to replace Calcium hydroxide dressing?
Calcium hydroxide and CO2
Toxicity
As a Root canal Sealer
Clinical significance
Classification
Composition
Properties
Leakage
Solubility
- In tissue fluids
- In chemical solvent
Biocompatibility
Antimicrobial
Toxicity
Conclusion
References
Techniques of direct composite restorationMrinaliniDr
Techniques of the direct composite restoration. Includes different instruments, matrix system, wedges, bevel, etching, bonding, and placement of composite along with finishing and polishing and clinical management
dental Monoblock obturation technique or concept in endodonticsAhmed Ali
dental Monoblock obturation technique or concept in endodontics which are classified into primary ,secondary & tertiary based upon resin , now the bioceramics
Isolation is very important aspect in clinical dentistry. Rubber dam plays very important role in isolation in pediatric dentistry. In day to day clinical dentistry rubber dam becames choice of isloation among dentists. This presentation covered everything about rubber dam and recent advances of it. Parts of clamps, forceps, types of sheets and technique of usng rubber dam.
In this lecture I explain the basic concept of root canal filling or what called obturation. The lectures discuss different techniques used in that matter in step-by-step fashion and explanatory pictures.
It is directed to the level of undergraduate mind.
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
Critical review on glass ionomer seal under composite resin of obturated root...Ziad Abdul Majid
Introduction: The root canal treated teeth need an adhesive seal for coronal leakage prevention. Glass ionomer sealant is the usual interface used between the coronal restoration and dental hard tissue however when composite resin material is used as a coronal restoration, some dental clinician prefer not to use it. The aim of this review is to determine the need to seal the orifice of an obturated root canal with glass ionomer under composite resin to prevent microleakage. Material and methods: Electronic searches were performed in the Pubmed and Scopus databases using relevant keywords. Textbook searching was also applied. Following selection, articles were fully reviewed to ensure that they met inclusion/ exclusion criteria. Results: The intracoronal sealing abilities of a wide variety of restorative materials have been investigated, assessed and compared within the dental literature. Conclusion: No definitive guidelines were found regarding the use of orifice sealing materials following endodontic treatment. This review was not able to answer the research question, and further investigation is required to achieve this goal.
Restoration of endodontically treated teethSanket Pandey
Seminar on restoration of endodontically treated tooth.
Credits to Cohen, Ingle, Respected researchers for their research in this field.
and everyone who previously tried to make a good presentation using the research work.
Similar to Double seal in endodontics and conservative dentistry (20)
Global launch of the Healthy Ageing and Prevention Index 2nd wave – alongside...ILC- UK
The Healthy Ageing and Prevention Index is an online tool created by ILC that ranks countries on six metrics including, life span, health span, work span, income, environmental performance, and happiness. The Index helps us understand how well countries have adapted to longevity and inform decision makers on what must be done to maximise the economic benefits that comes with living well for longer.
Alongside the 77th World Health Assembly in Geneva on 28 May 2024, we launched the second version of our Index, allowing us to track progress and give new insights into what needs to be done to keep populations healthier for longer.
The speakers included:
Professor Orazio Schillaci, Minister of Health, Italy
Dr Hans Groth, Chairman of the Board, World Demographic & Ageing Forum
Professor Ilona Kickbusch, Founder and Chair, Global Health Centre, Geneva Graduate Institute and co-chair, World Health Summit Council
Dr Natasha Azzopardi Muscat, Director, Country Health Policies and Systems Division, World Health Organisation EURO
Dr Marta Lomazzi, Executive Manager, World Federation of Public Health Associations
Dr Shyam Bishen, Head, Centre for Health and Healthcare and Member of the Executive Committee, World Economic Forum
Dr Karin Tegmark Wisell, Director General, Public Health Agency of Sweden
India Clinical Trials Market: Industry Size and Growth Trends [2030] Analyzed...Kumar Satyam
According to TechSci Research report, "India Clinical Trials Market- By Region, Competition, Forecast & Opportunities, 2030F," the India Clinical Trials Market was valued at USD 2.05 billion in 2024 and is projected to grow at a compound annual growth rate (CAGR) of 8.64% through 2030. The market is driven by a variety of factors, making India an attractive destination for pharmaceutical companies and researchers. India's vast and diverse patient population, cost-effective operational environment, and a large pool of skilled medical professionals contribute significantly to the market's growth. Additionally, increasing government support in streamlining regulations and the growing prevalence of lifestyle diseases further propel the clinical trials market.
Growing Prevalence of Lifestyle Diseases
The rising incidence of lifestyle diseases such as diabetes, cardiovascular diseases, and cancer is a major trend driving the clinical trials market in India. These conditions necessitate the development and testing of new treatment methods, creating a robust demand for clinical trials. The increasing burden of these diseases highlights the need for innovative therapies and underscores the importance of India as a key player in global clinical research.
Navigating Challenges: Mental Health, Legislation, and the Prison System in B...Guillermo Rivera
This conference will delve into the intricate intersections between mental health, legal frameworks, and the prison system in Bolivia. It aims to provide a comprehensive overview of the current challenges faced by mental health professionals working within the legislative and correctional landscapes. Topics of discussion will include the prevalence and impact of mental health issues among the incarcerated population, the effectiveness of existing mental health policies and legislation, and potential reforms to enhance the mental health support system within prisons.
CHAPTER 1 SEMESTER V - ROLE OF PEADIATRIC NURSE.pdfSachin Sharma
Pediatric nurses play a vital role in the health and well-being of children. Their responsibilities are wide-ranging, and their objectives can be categorized into several key areas:
1. Direct Patient Care:
Objective: Provide comprehensive and compassionate care to infants, children, and adolescents in various healthcare settings (hospitals, clinics, etc.).
This includes tasks like:
Monitoring vital signs and physical condition.
Administering medications and treatments.
Performing procedures as directed by doctors.
Assisting with daily living activities (bathing, feeding).
Providing emotional support and pain management.
2. Health Promotion and Education:
Objective: Promote healthy behaviors and educate children, families, and communities about preventive healthcare.
This includes tasks like:
Administering vaccinations.
Providing education on nutrition, hygiene, and development.
Offering breastfeeding and childbirth support.
Counseling families on safety and injury prevention.
3. Collaboration and Advocacy:
Objective: Collaborate effectively with doctors, social workers, therapists, and other healthcare professionals to ensure coordinated care for children.
Objective: Advocate for the rights and best interests of their patients, especially when children cannot speak for themselves.
This includes tasks like:
Communicating effectively with healthcare teams.
Identifying and addressing potential risks to child welfare.
Educating families about their child's condition and treatment options.
4. Professional Development and Research:
Objective: Stay up-to-date on the latest advancements in pediatric healthcare through continuing education and research.
Objective: Contribute to improving the quality of care for children by participating in research initiatives.
This includes tasks like:
Attending workshops and conferences on pediatric nursing.
Participating in clinical trials related to child health.
Implementing evidence-based practices into their daily routines.
By fulfilling these objectives, pediatric nurses play a crucial role in ensuring the optimal health and well-being of children throughout all stages of their development.
Medical Technology Tackles New Health Care Demand - Research Report - March 2...pchutichetpong
M Capital Group (“MCG”) predicts that with, against, despite, and even without the global pandemic, the medical technology (MedTech) industry shows signs of continuous healthy growth, driven by smaller, faster, and cheaper devices, growing demand for home-based applications, technological innovation, strategic acquisitions, investments, and SPAC listings. MCG predicts that this should reflects itself in annual growth of over 6%, well beyond 2028.
According to Chris Mouchabhani, Managing Partner at M Capital Group, “Despite all economic scenarios that one may consider, beyond overall economic shocks, medical technology should remain one of the most promising and robust sectors over the short to medium term and well beyond 2028.”
There is a movement towards home-based care for the elderly, next generation scanning and MRI devices, wearable technology, artificial intelligence incorporation, and online connectivity. Experts also see a focus on predictive, preventive, personalized, participatory, and precision medicine, with rising levels of integration of home care and technological innovation.
The average cost of treatment has been rising across the board, creating additional financial burdens to governments, healthcare providers and insurance companies. According to MCG, cost-per-inpatient-stay in the United States alone rose on average annually by over 13% between 2014 to 2021, leading MedTech to focus research efforts on optimized medical equipment at lower price points, whilst emphasizing portability and ease of use. Namely, 46% of the 1,008 medical technology companies in the 2021 MedTech Innovator (“MTI”) database are focusing on prevention, wellness, detection, or diagnosis, signaling a clear push for preventive care to also tackle costs.
In addition, there has also been a lasting impact on consumer and medical demand for home care, supported by the pandemic. Lockdowns, closure of care facilities, and healthcare systems subjected to capacity pressure, accelerated demand away from traditional inpatient care. Now, outpatient care solutions are driving industry production, with nearly 70% of recent diagnostics start-up companies producing products in areas such as ambulatory clinics, at-home care, and self-administered diagnostics.
Leading the Way in Nephrology: Dr. David Greene's Work with Stem Cells for Ki...Dr. David Greene Arizona
As we watch Dr. Greene's continued efforts and research in Arizona, it's clear that stem cell therapy holds a promising key to unlocking new doors in the treatment of kidney disease. With each study and trial, we step closer to a world where kidney disease is no longer a life sentence but a treatable condition, thanks to pioneers like Dr. David Greene.
Explore our infographic on 'Essential Metrics for Palliative Care Management' which highlights key performance indicators crucial for enhancing the quality and efficiency of palliative care services.
This visual guide breaks down important metrics across four categories: Patient-Centered Metrics, Care Efficiency Metrics, Quality of Life Metrics, and Staff Metrics. Each section is designed to help healthcare professionals monitor and improve care delivery for patients facing serious illnesses. Understand how to implement these metrics in your palliative care practices for better outcomes and higher satisfaction levels.
3. Contents:
Introduction
Definition
Review of the articles
Purpose of double seal
Material used for coronal sealing
Combination of material used
Results of different combinations
Conclusion
References
4. Introduction
The ultimate goal of root canal therapy is to conquer the complex root
canal system by perfect obturation. Even after a three dimensional obturation
of the system, coronal restoration may fail to provide a perfect seal and may
permit microorganism & their toxins along the canal walls to their periapical
tissue, leading to the failure of the treatment. So the quality of the coronal seal
should be adequate to prevent micro leakage in to the canal space.Thus the
concept of double seal came .
5. Lack of satisfactory temporary restoration during
endodontic therapy ranked second amongst the
contributing factors in continuing pain after
commencement of treatment.
6. A DOUBLE seal consisting of gutta percha underneath material such as temporary
cement ; used to close the coronal opening in a tooth during endodontic treatment.
Seal is defined as something that blocks entry into or out of a container or other
objects. Hence it is a difficult term to justify or use clinically since complete sealing
is impossible with current available dental materials and due to the porous
structure of the tooth itself.
7. •Many materials can be used to achieve some of these goals for effective inter-
appointment temporization. It is essential to have adequate knowledge of temporization
techniques and material properties in order to satisfy a wide variety of clinical
requirements such as time , occlusal load and wear ,complexity of access and absence
of tooth structure.
Coronal 3-4 mm should be left for the placement of this double seal.
Numerous factors may effect coronal leakage in root canal treatment including
The oral flora
The root canal sealer
The smear layer
Coronal restoration
8. •Sommer,Ostrander and Crowley state that the pulp chamber opening
should be sealed by applying a softened layer of gutta-percha over the dressing ,
with a space of 1.5 mm alllowed for the final cements.
• Stewart ,mention that a double seal is generally employed to prevent
medication from escaping from the tooth.The inner seal generally consist of
Gutta percha and an outer seal of “some cement substance is then placed.’’
•Grossman in discussing the selection of a temporary filling material, states
that zinc oxide –eugenol cements are probably best and that gutta percha
preparations, intermediate and zinc phosphate cements are the worst. He
recommends the use of zinc phosphate cement over gutta percha to seal
posterior teeth and zinc oxide eugenol over gutta percha over anterior teeth.
Related studies:
9. • Fischer made a careful study of the zinc phosphate cement and other
permanent filling materials. He found that under the conditions of testing used
in his study, every filling material tested showed some degree of fluid
penetration at the margin.
• Massler and Ostrovasky ,and Weiss tested the relative sealing properties
of a number of commonly used filling materials. The results of these two studies
confirmed the reports of previous investigators, that is that the commonly used
filling materials exhibit marginal leakage in a short period of time and that ,at
room temperature, zinc oxide eugenol cement and amalgam are most effective
sealing agent
10. .
• Saunders and saunders (1990)study indicated that pulp chambers
restored with glass ionomer ,cermet cement,or amalgam leaked significantly
less than those filled with gutta percha and root canal sealer.
•Magura et al(1991) suggested that when temporizing the access opening
of an endodontically treated tooth consideration must be given to the material
choosen to fill the voids.Their results suggested that a thickness of IRM greater
than 3 mm should be used or the clinician should use double seal, possibly Cavit
And IRM to ensure the integrity of the root canal.
• Magura et al(1993) evaluated the coronal leakage of human saliva in
endodontically treated teeth.They reported that saliva penetration at 90
days was significantly greater than seen at 2,7,14,28 days.This study
came to conclusion that obturated canal that have been exposed more
than three month should be re-treated.
11. Few studies have tested the sealing ability of temporary restorative materials
in various situations
Pai et al.(1999) found micro leakage at the interface between amalgam
restoration & IRM,
Caviton & a double seal of Caviton & IRM temporary restorations was less than
the leakage of temporary materials & tooth cavity walls
In another in vitro study access cavities were prepared entirely in amalgam
restorations and temporised with CAVIT,CAVIT-G,TERM ,zinc phosphate cement
and observed microleakage
Polycarboxylate cement, glass ionomer cement, apart from zinc phosphate &
polycarboxylate cement all the tested material provided a leak proof seal
It has also been demonstrated that access cavity prepared with composite resin
& temporised with ZOE or cavit showed less leakage when compared with
amalgam was used in place of composite.
12. Over the years various materials referred to as ‗Intra-orifice
barriers‘ have been sought by investigators to prevent coronal
micro leakage & help produce a secondary seal for obturated
canal. Thus along with time many sealing material for coronal
sealing was tested.
13. Materials used for coronal sealing are:
• Gutta percha
• Amalgam,
•Intermediate restorative material
•Glass ionomer
•Composites
•Cavit
•Resin bonded cement
•Dental adhesives
•Super-EBA
•TERM
•Coltosol
•White & Grey MTA
14. Gutta percha:
Introducer :Bowman(1867)
Sapodilla Family,Genera Payena
Trans isomer of 1,4-poly isoprene
Two
crystalline
forms
Alpha
1)Direct
form2)Brittle
3)Low melting point
4)Ahesive5)Good
flow
Beta
1)Commercial
form
2)Flexible
15. GUTTA PERCHA : EVOLUTION INTO
DENTISTRY
―GETAH‖- meaning gum
―PERTJA‖- name of the tree in Malay
language
First introduced to dentistry as a temporary
filling material by Edwin Truman.
16. Composition of Gutta Percha
Matrix-Gutta Percha 20%
Filler-Zinc oxide 66%
Radiopacifier –heavy metal sulphates 11%
Plasticizer –Waxes and Resin 3%
17. Gutta percha is available in conventional & standardized sizes
.
Conventional sizes include:
•Extrafine
•Fine fine
•Fine
•Medium
•Fine Medium
•Large
•Extra Large
Standerdized size:
•ISO 2% from size nos.15 to 140
•Greater taper Gutta percha like 4 or 6%
•Protaper like F1 ,F2,F3, F4, F5 which is a variable taper
shaping instruments.
18. Type of Cone:
Standardized cones: Corresponds in diameter and taper of root canal shaping instruments
according to ISO sizes. Sizes of gutta percha Ranges from ISO 10 to ISO
140 and taper available in 0.02,0.04,0.06,0.07,0.08 &0.09
Non standardized : The taper is constant but there is no tip diameter. Hence they need
to be customized.Availble in sizes x-fine,fine-fine,medium-fine,fine-
fine –medium,medium,medium-large & large
Accessory cones : Larger taper descriptive size may be used for lateral compaction
Greater taper cones: Cones with 0.04 or 0.06 taper used together with special engine
driven root canal shaping instruments
Compaction cones : Taper corresponds to the taper of fine spreaders
Another classification of Gutta percha
19. Advantages of gutta percha:
Do not shrinke after insertion
Easily Sterilized
Does not encourage bacterial growth
Radio opaque,non-staining
Impervious to moisture
Easy removal
Least toxic and less irritating
Disadvantage of gutta percha:
Lack of rigidity
Lack of length controll
20. Protaper gutta percha
Recent advances in instrument designs
and materials have resulted in the use of
Ni-Ti rotary and hand PROTAPER
instruments for better shaping and
cleaning of the teeth.
Ni Ti rotary and hand protaper instruments
used to prepare Root canal
in a crown down technique .
Gutta percha cones are now produced to
match the taper of canals prepared
with Protaper hand & rotary instruments.
21. With NiTi protaper rotary preparation of the root canal and use
of a sealer, these cones provides three dimensional obturation
of the root canal over its whole length without the use of
accessory cones or time spent on lateral condensation.
Manufacturers of gutta percha points matching the canal
shapes created by instruments of similar taper claim that they
can fill tapered canal effectively.
Available in boxes of individual sizes,F1, F2, F3 & assortments
of F1 to F3 and F4 to F5
.
22. Protaper next
These unique gutta percha points mirror the progressively tapered designs
of PROTAPER NEXT rotary finishing files for system based efficacy.
Precision machined gutta-percha master cones
No more size irregularities from hand rolling
Consistent sizing between precise and predictable fit
The variable –tapered designs conforms to the file and shaped root canal
Micronized formula helps deliver warm gutta percha 4.5 mm beyond a heat
source
Working temperature of 105-108ºC
Latex free
Available in X2,X3,X4,X5
23. •Gutta percha & temporary stopping gutta percha were among the first material
tested,with less than ideal characteristics.
•Paris et al. found that gutta percha temporary fillings leaked when subjected
to two extreme temperature 4-60 degree.
•Findings from different studies,Kakar & Subramanian said that Gutta percha is
Inferior to ZOE with or with out thermocycling.
•Thus gutta percha is not a commonly used temporary restorative material & not
recommended for this purpose in endodontics.
24. Amalgam
Rhein in 1897 used amalgam to seal the pulp canal after complete root resection.
Initially copper amalgam was used and later silver amalgam was used widely.
a·mal·gam: any alloy of mercury with
another metal or other metals [silver
amalgam is used as a dental filling]†
25. Classification of amalgam alloy:
Based on Copper content:
•Low copper alloys :copper less than 6%
•High copper alloys:copper more than 6%
1. Admixed or dispersed or blended alloys
2. Single composition or unicomposition alloys
Based on Zinc Content
• Zinc containing alloys
• Zinc-free alloys
Based on shape of the Alloy Particle
• Lathe cut alloys
• Spherical alloys
• Spheroidal alloy
Based on number of alloyed metals
• Binary alloys,e.g .silver tin
• Ternary alloys,e.g.silver-tin-copper
• Quaternary alloys,e.g.silver-tin-copper-indium
Based on Size of Alloy
• Micro cut
• Macro cut
26. Alloy Powder Composition
Type Ag Sn Cu Zn Other
Low copper 63-72 26-28 2-7 0-2 —
High-Cu admixed
lathe-cut
40-70 26-30 12-30 0-2 —
High-Cu admixed
spherical
40-65 0-30 20-40 0 0-1 Pd
High-Cu unicomp-
ositional spherical
40-60 22-30 13-30 0
0-5 In,
0-1 Pd
compositions in weight percent
27. Amalgam Capsules
Contain (in separate
compartments):
powdered amalgam
alloy
liquid mercury
Some are manually
activated, others self-
activated
Pestle usually
included
30. Properties of Mercury
Only liquid metal at room temperature
Evaporation rate
Theoretical maximum is 57.9 µg·cm2·s–1 from pristine,
oxide-free surface into a vacuum (= 57,900 ng·cm2·s–1)
Measured rate in vacuum is ~40 µg·cm2·s–1 (= ~40,000
ng·cm2·s–1)
Oxidation of Hg lowers rate by factor of 1000
31. Mercury Dose from Amalgam
Person with average number of fillings (7) would
absorb ~1.6 µg/day
Person with a moderately high number of fillings (13)
would absorb ~3 µg/day
Absorbed dose of mercury from food, water, and air is
5.7 µg/day
32. Disadvantages:
•The placement of amalgam as restorative of choice in
which has metallic post or crown for restoration could
create galvanic couple and generate significant amount
of galvanic current.
• Sufficient depth must be provided to place base
material such as calcium hydroxide or zinc oxide
eugenol to prevent galvanism.
•Amalgam may be scattered in the perforated area and
may cause staining.
33. Zinc phosphate cement:
• Studies regarding the sealing ability of the zinc phosphate cement is controversial.
In an in vivo study by Krakow et al.1977 said that no leakage was found in
maximum cases.
•In another study using the fluid filtration method to test microleakage,
Zinc phosphate did not show significant microleakage
•Bobotis et al.1989 found visible micro leakage after temporisation with ZnPO4
cement.
•It was found that zinc phosphate cement was inferior to zinc oxide/calcium
sulphate based material when compared to the property of condensed amalgam
and ZOE.
•Thus Zinc phosphate cement is not widely used for endodontic temporisation
in combination with any other sealing material.
34. Polycarboxylate cement:
•This material has been tested as a temporary restoration in vitro studies with
conflicting result.
•Marosky et al.(1977) found polycarboxylate cement to provide least desirable
seal when compared to Temp seal,Cavit,ZOE,zinc phosphate cement and IRM.
•Polycarboxylate cement is not commonly used in endodontics as its clinical
effectiveness is not well established
35. Zinc oxide eugenol
PCS regular & Extended Working Time PCS EWT
Powder:
Zinc Oxide 34-41.2%
Precipatated silver 25-30%
Oleo resins 30-16%
Thymol iodide 11-12%
Liquid:
Oil cloves 78-80%
Canada Balsam 20-22%
Advantage:
• Excellent lubricating property
•More working time
•Germicidal
•Greater bulk
Disadvantage
•Staining ability
•Rapid setting in high heating
• Type IV zinc oxide eugenol cements are used for intermediate restoration
36. Zinc oxide eugenol
Advantage Disadvantage
Ease of manipulation
Plasticity
Radio opaque
Germicidal
Minimal staining
Accepted working time
Low setting time
Good sealing
Irritation
Not easily absorbed from
periapical tissue
Zinc eugenolate is
weak & unstable material
Has staining property due to
silver content
37. Liquid/Powder
• Mixed on an oil-resistant paper pad.
• Mixing time ranges from 30 to 60 seconds.
• Setting time in the mouth ranges from 3 to 5 minutes.
Paste
• Supplied as a two-paste system as temporary cement.
• Pastes are dispensed in equal lengths on a paper pad
and mixed.
Zinc oxide eugenol is supplied as:
38. Many temporary restoration products are ZOE based with or without
reinforcement.
Plain ZOE with a powder to liquid of 4:1g/ml as commonly used results in a
poor initial seal.
A lower water W/P ration of 2:1 gives better initial seal ability but seal slightly
deteriorate with time(Pashley et al.)
Simple ZOE temporary cement was found less effective in precluding radio-activ
tracer leakage when compared to cavit & temp seal , but superior to
zinc phosphate cement ,IRM & polycarboxylate cement.(Maroksy et al.1977)
After thermocycling,Dentemp(commercial name of ZOE ) ,is less effective
in preventing silver nitrate penetration when compared to TERM & three different
cavit preparation., But almost equally effective when compared to IRM
Properties of ZOE based cements:
39. Influence on final restoration
•Material used for provisional restorations in endodontics can affect the polymerisation
& adhesion obtained with composite resins & other materials used to restore
endodontically treated tooth.
•Residual eugenol may have a deleterious effect on physical properties of composite
•Residual eugenol may effect the bond strength of composite
•Incidence & extent of marginal leakage when temporised with Zinc oxide eugenol
•Thus not very effective in Double seal technique
40. IRM(Intermediate restorative material)
Dentsply International,Caulk Division,USA
Temporary filling material in powder and liquid form.
•It’s a ZOE cement reinforced with polymethyl methacrylate.
•This reinforcement provides the restoration with improved
compressive strength, abrasion resistance & hardness(Blanley et al
1981,Anderson et al.1990)
•It provides more optimal physical properties.
•A softer mix of IRM provides better sealing ability due to hydrolysis and
release of eugenol.
•Leakage of IRM increased when subjected to thermal stress.
•Other in vitro studies using radio isotopes & electrochemical method
showed more favourable results with IRM when compared to cavit .
41. Powder contains
75% zinc oxide
20% polymethacrylate
Liquid contains
greater than 99% eugenol
less than 1% acetic acid.
.
Composition:
42. Coming to conclusion from different studies ,It can be stated that ZOE
temporary restorative material including IRM ,can provide adequate
resistance to bacterial penetration during the course of endodontic treatment
especially when used with low P/L ratio. It seals better than amalgam and it
is not affected by root end conditioning agents. It has good tissue
tolerance.It does not have any hard tissue forming capacity.
43. Glass ionomer
Glass ionomer has variety of application in the field of endodontics(Friedman 1990)
It consists of poly acrylic acid and a glass
powder such as alumino silicate.
Glass ionomer cements can be either
light or chemical cure.
Seal and marginal adaptation of the light
cure is superior to the chemical cure.
Seal is better than amalgam and similar
to that of IRM.
Glass ionomer cements are susceptible
to attack by moisture during initial setting
45. Types of Glass Ionomer
Type I
• For the cementation of metal restorations and direct-bonded orthodontic
brackets.
Type II
• Designed for restoring areas of erosion near the gingiva.
Type III
• Used as liners and dentin bonding agents.
Type IV
Fissure sealants
Type V
Orthodontic cements
Type VI
Core build up
46. Benefits of Glass Ionomer:
Powder is an acid-soluble calcium. The slow release of fluoride from this
powder aids in inhibiting recurrent decay.
Causes less trauma or shock to the pulp than many other types of cements.
Low solubility in the mouth.
Adheres to a slightly moist tooth surface.
Has a very thin film thickness, which is excellent for seating ease.
47. Supply of Glass Ionomer:
Powder/liquid
• Mixed manually on a paper pad or
a cool, dry glass slab.
• Glass slab increases the working
time of the cement.
Premeasured capsules
• Triturated and expressed through
a dispenser.
48. Glass-ionomer alone or on top of an IRM base provided a significantly
superior seal against penetration of S.mutans when compared to cavit,
IRM and glass-ionomer on a cavit base
The adhesion mechanism of glass-ionomer cements explains their acceptable
sealing ability.(Watson 1999)
Moreover glass-ionomer cement posses excellent antibacterial property
against bacterial strains(Tobias et al ,1985)
The antibacterial activity of the material is attributed to the release of fluoride
,low Ph, and /or the presence of certain cations,such as strontium & zinc.
49. • Mineral trioxide aggregate is a new biocompatible material
with numerous exciting clinical application in endodontics.
• MTA was introduced by Torabinejad et Al at Loma Linda
university in 1993 as a root-end filling material and for repair
of lateral perforation .
• It has been patented and has received approval of FDA and is
commercially available as Pro-Root MTA by Dentsply
International .
• Several in vitro and in vivo studies have shown that MTA
prevents microleakage, is biocompatible and promotes
regeneration of original tissues when placed in contact with
periradicular tissues or dental pulp.
Mineral trioxide aggregate
50. MTA (Mineral Trioxide Aggregate)
Scanning electron microscopic analysis indicated that cementoblasts
could reattach and grow on MTA. In addition strong expression of
osteocalcin gene was seen after application of MTA. MTA also
increases the production of both proinflammatory and anti
inflammatory cytokines from osteoblasts
ProRoot MTA(Dentsply)
Mineral Trioxide Aggregate
Composition
Available in White & Grey color
Grey color contains---
Tricalcium silicate
Dicalcium silicate
Bismuth oxide
Calcium sulphate
Tetracalcium aluminoferrite
White color MTA contains same composition as grey color
MTA except
Lack of tetra calcium alumino-ferrite
51. •MTA has longest setting time of 2 hours and 45 minutes.
•Compressive strength is lowest at 24 hours-40 MPa, but it increases to
67MPa , 21 days after mixing.
•The compressive strength, radiopacity and the solubility of MTA are as
those of amalgam, super EBA and IRM.
• But it is more radiopaque than IRM and super EBA. Initially pH is of 10.2,
which rises to 2.5, three hours after mixing;
•pH is about 9.5 at 168 hours after mixing.
• Mean particle size is 10µm.Range of particle size is from 0.1 µm to 100
µm.
•Holland et al theorized that the tricalcium oxide in MTA reacts with tissue
fluid to form calcium hydroxide resulting in hard tissue formation.
•Studies in dogs have reported with less peri-radicular inflammation and
cementum deposition immediately adjacent to the material.
Properties:
52. continuation.....
Has biological properties like calcium
hydroxide
High compressive strength
Produce high setting non resorbable surface
Hydrophilic nature
Low solubility, resist to marginal leakage
Biocompatible
Non sticky
Bacteriostatic
Disadvantages:
Difficult to manipulate
Long setting time
Costly
53. Management
Pro root (commercial name of MTA) is mixed with anaesthetic solution or
sterile water to a heavy, cake like consistency.
A small amount of the material is picked and introduced into the canal
with a micro-tube carrying device, such as customized spinal tap needle or
on the side of West perforation repair instrument.
Pro root is then tamped and coaxed down the canal to approximate
length using a customized nonstandard gutta percha cone as a flexible
plugger.
54. SETTING REACTION
• On addition of water compound in MTA react to produce calcium
silicate hydrate gel that is calcium hydroxide contained in a
silicate matrix.
• The dissolution of anhydrous phase of MTA occurs followed by
the crystallization of the hydrate in a interlocking mass which
consists of cubic and needle like crystal.
• In the crystal kinetics point of view the complexity of MTA
resulted in different nucleation rates and some parts move
rapidly than others to construct the epitaxillary growth.
• According to patent of MTA C3S is a predominant phase and play
an important role in its hydration behaviour.
55. • The hydration of C3S is follows chemical process and
produces calcium silicate hydrate and calcium hydroxide.
The set MTA exhibits both crystalline and amorphous phases.
• The crystalline material is essentially calcium oxide and
amorphous phase is calcium phosphate.
• MTA consists of hydrophilic particles and sets in presence of
moisture.
• In clinical setting a moist cotton pellet need to be placed
over MTA to help in setting reaction.
56. 2. USAGE TECHNIQUE
To prepare medium size portion: one measure of MTA powder + 01 drop of distilled water.
a- Put one measure of powder and one drop of distilled water upon a
sterilized glass plate;
b- Spatulate both for 30 seconds until the perfect homogeneity of the
components. The cement got must have a sandy consistency, similar to
amalgam, but more humid;
c- Insert the spatulated cement in the place desired, using a sterilized
amalgam-place or another professional instrument of your preference;
d- Condensate the material inside the dental cavity.
57. Studies on adaptation/microleakage
• Fluid transport models comparing microleakage of MTA and
amalgam or EBA, amalgam and MTA showed less microleakage
with MTA (Yasshushiri et al )
• Torabinejad et Al evaluated marginal adaptation using SEM
revealed that MTA had better adaptation than other material.
• Endotoxin studies by Torabinejad et Al also confirms superior
sealing ability of MTA using E.Faecalis to test sealing property.
58. •Study by Lawley et Al using PCR followed by
reverse blot confirms superior sealing and
adaptation of MTA.
•Schress found that MTA did not allow
passage of strict anaerobes for duration of
47 days. MTA also gives seal against
S.Epidermidis,F.nucleatum,S.Marcesences
59. Mechanism:
MTA’ s sealing ability and better marginal
adaptation is probably due to its hydrophilic nature,
longer setting time and slight expansion when it is
cured in moist environment.
MTA contains 5% gypsum that expands during
setting contributing to better adaptation .
60. Studies:
Investigation of why MTA appears to induce
cementogenesis found that material seemed to
offer a biologically active substrate for osteoblasts,
allowing good adherence of the bone cells to the
material while also stimulating production of
cytokines.
Koh et Al found that MTA causes an increase in
production of interleukin IL-1α, IL-1β, IL-6 and
osteocalcin.
Osteocalcin is an abundant protein and may be an
indicator or bone matrix production.
Mitchell et Al found that set MTA induced
production of IL-6, IL-8, and macrophage colony
stimulating factor
61. IL-8 promotes the development of new blood
vessels and activate precursor of osteoblasts.
Macrophage stimulating factor may have a
significant function in osteoclast development and
maturation.
The source or origin of new cementum is not
clearly understood, Two possibilities exists, one
derived form remaining PDL or one from growing
connective tissue from bone.
62. White MTA in concentration of 50 mg/ml may
exert an antifungal effect against C.albicans a
period of up to 30 days.
Recently it has been suggested to mix
chlorhexidine to MTA to enhance its
antibacterial properties ,however its not clear
what effect chlorhexidine has on physical and
chemical properties of MTA.
63. Although EBA, ZOE, and MTA are ineffective against a number
of bacteria MTA is superior to others due to its sealing ability
preventing migration of bacteria and some antibacterial
activity against facultative anaerobes.
64. ROOT-END FILLING:
Numerous materials have been used as a root-end filling
material. The main disadvantage include their inability to
prevent egress of irritants from infected root canal into peri
radicular tissues, lack of biocompatibility, and their inability to
promote regeneration of peri radicular tissues to their
preassessed status and normalcy.
MTA is superior to other material as it provides “DOUBLE
SEAL” that is physical seal due to its excellent sealing
property and biological seal due to regeneration of cementum
over it.
65. Precaution for MTA use:
a. MTA –material should be kept in closed container to avoid moisture
b. Material should be immediately placed after mixing to avoid
dehydration during setting
c. Working time is 5 minutes,if more working time is needed then
It should be covered by moist gauge or add a small drop of water during
capillary condensation technique
USE:
As pulp capping material
Perforation repair agent
Root end filling material as apical barrier
As a paste filling material for obturation
66. •MTA as a double seal in combination with GIC &/or IRM is significantly
better than any other combination.
•Thus MTA with a combination of GIC and / or IRM can be recommended as
coronal sealing material to prevent microleakge in an endodontically treated tooth.
•MTA without secondary seal leak significantly.
www.endoexperience.com/documents/Endotemps.pdf
67. TERM
(composite resin)
Temporary restorative materials for endodontics
This material is a single component light curable resin
Contains:
•Urathane dimethacrylate polymer-matrix/binder
•Inorganic radio opaque filler
•Organic prepolymerised filler
•Coupling agent-organo silanes
•Hydroquinone-inhibit to prevent premature polymerisation
•Opacifier-titanium Di-oxide & aluminium oxide
•UV absorbers-for color stability
•Pigments
•Initiators
68. Properties:
Undergoes polymerisation shrinkage 2.5% of its volume
Has higher hardness ,tensile strength & compressive
strength in comparison to cavit
Sealing ability is effected by intra-canal medicaments
Thermocycling causes increased micro-leakage
Inferior to IRM & Cavit in the context of physical properties
but marginal sealing ability is better
Dye penetration is more after thermocycling when
compared to Cavit
69. Properties:
Undergoes polymerisation shrinkage
Contraction is followed by expansion owing to secondary water
sorption
Minimum thickness for effective cavity sealing was investigated
in vitro using thermocycling and fluid filtration technique...it was
found that 1-3 mm thick TERM is effective for cavity sealing.
TERM has higher hardness,tensile & compressive than Cavit.
Sealing ability is not effected by intra canal medicament(Rutledge
& Montgomery 1990)
Continued...
Uranga et al.(1999) found that composite resin & resin modified
glass ionomer cement provided a better seal against methylene
blue than TERM
70. TERM Can be used in combination with GIC in double seal technique.
But due to polymerisation shrinkage of TERM micro leakage is observed.
Thus not very effective. But the result is controversial
71. (Cavit)
It’s a premixed temporary filling material
Composition:
Zinc oxide
Calcium sulphate
Zinc sulphate
Glycol acetate
Polyvenyl acetate resins
Polyvinyl chloride acetate
Triethanol amine
Pigments
Properties:
•Cavit posses high co efficient of linear expansion resulting from water sorption
•Hygroscopic in nature
•Excellent marginal sealing ability
•Compressive strength is half of the ZOE.
•Properties are not effected by intracanal medicaments
•More effective than TERM & IRM
Zinc oxide/calcium sulphate preparation
72. Types of Cavit
A. Cavit
B. Cavit -G
C. Cavit-W
D. Cavidentin( calcium sulphate based addition of potassium
aluminium sulphide as catalyst,thymol as antiseptic)
Differ in their content of resin & their resulting hardness & setting.
The hardness and dimensional stability of cavit,cavit –w,cavit-G decrease
respectively
Provides equal water tight seal
Cavidentin &Cavit G were almost equally effective
Cavit
73. Advantages:
Easy manipulation
Premixed
Adequate seal
Disadvantages:
Less hardness
Less wear resistance
Slow setting
Deterioration with time
Continution...
74. ).
• In in vivo studies, no leakage or minor leakage was found in 27 out
of 32 cases when Cavit was used to temporize access cavities in
anterior teeth and only15% of cases tested showed gross leakage. In
another study,
• Cavit in a 4 mm thickness provided the best seal over a 3 week
temporization period when compared to IRM and TERM (Beach et
al. 1996).
75. A double seal using cavit as an inner layer and IRM as an outer layer
has been recommended to compensate for the undesirable physical
properties of cavit .Furthermore this combination showed better dentine
adaptation when compared to IRM alone(Pal et al.1999)
76. CALCIUM HYDROXIDE CEMENT
It’s a rigid self limiting ,radio opaque calcium hydroxide composition.
Due to their alkaline nature they also serve as a protective barrier
against irritants from certain restoration.Recently ,a light cured
calcium hydroxide base material and a calcium hydroxide root canal
sealing paste have been introduced.
Application:
•For direct & indirect pulp capping
•As low strength bases beneath silicate & composite restoration for pulp
protection
•Apexification
Commercial names:
• .Self cured –Dycal ,Life ,Care,Calcidor
• Light cured-Plasma VLC dycal
77. Available as
Two paste system ,base &
catalyst
Light cured system
Single paste in syringe
Powder form(mixed in distilled
water)
Composition:
Base paste:
1,3 Butylene glycol disalicylate
Zinc oxide
Calcium phosphate
Calcium tungstate Iron
Oxide pigments
Catalyst paste:
Calcium hydroxide
N-ethyl-0/p-toluene sulfonamide
Zinc oxide
Titanium Dioxide
Iron oxide pigments
78. Properties:
Poor mechanical properties
Low compressive strength(10-27MPa after 24 hours)
Low tensile strength(1.0 Mpa)
Low modulus of elasticity
Thermal insulation is possible when used in 0.5 mm in
thickness
The cement is alkaline in nature,
High alkalinity & its consequent antibacterial & protein
lysing effect helps formation of reparative dentin
79. Coltosol
(Colten Whaledent,Mahwah,NJ,USA)
Composition:
•Zinc oxide
•Zinc sulphate
•Calcium sulphate hemihydrate
PROPERTIES:
•Coltosol hardens within 20-30 min.when in contact with moisture
•It is designed for the short term temporisation not exceeding 2 weeks
•Not very effective for endodontic field
80. Materials that can be used in combination in as DOUBLE SEAL are:
Glass ionomer Type II over gutta percha followed by light cure composite resin
as the final seal
Mineral trioxide aggregate over gutta percha followed by Glass ionomer type II
as the final seal
Dycal over gutta percha followed by Glass ionomer Type II as the final seal
Mineral trioxide aggregate over gutta percha followed by intermediate
restorative material as the final seal
81. Combination of GIC & composite is a---
Well documented combination of restorative materials
Can be used for both anterior and posterior teeth
This laminate or “sandwich technique “ has been suggested primarily
for decreasing micro leakage
The combined glass ionomer & composite restoration provides a reliable
chemical bond to dentin
Micromechanical bonding of the composite to ionomer surface and an
acceptable esthetic result
But polymerisation shrinkage of composite may lead to micro leakage
82. The imperfect sealing of the GIC linings might be explained by their
hydrophilic properties,micro gaps and or porosities
.
Initial bond strength to dentin is not strong enough to withstand the
polymerisation shrinkage stress of resin composite.
Moreover GIC absorb considerable amount of fluid while setting
leading to micro leakage
83. MTA with GIC:
•Study was conducted by Hardy et al using MTA for furcation where it was
found that MTA without a secondary seal leaked significantly.
But result is controversial.
• Different studies have that MTA as a Double Sealing Material in combination
with GIC or IRM group can be preferred over the other combination.
• There is no significant difference between the combination of GIC or IRM
along with MTA
84. GIC with Dycal showed
Highest leakage among the combination used
So this combination is not very recommended
85. Methods of evaluation of leakage
Passive method of dye penetration
Fluid filtration & trasportation
methodology
Bacteria and toxin infiltration method
Dye extraction method
3D Computer assisted re-construction
86. Passive method of dye penetration
The phenomenon of capillarity is of utmost importance in this passive method
used mainly for assessing apical leakage, as the tooth apex is submerged in the
dye that penetrates through any space between the canal walls & filling materials
Next ,the teeth are sectioned longitudinally ,transversely ,or cleared and the
linear penetration of the dye is recorded.
Longitudinal sectioning method:
•The longitudinal sectioning method enables examination of the exposed filing
material and at the interface of dentinal wall on one side.
•Ahlberg et al. Suggested a variation of this technique ;where by roots are
worn down to visualize the leakage through a thin layer of dentin, thus reducing
the risk of dye dissolution during sectioning
•They also affirmed that this technique provides more reliable information about
the real leakage pattern than the transverse section or clearing
•The disadvantage is that in longitudinal sectioning the random choice of the
cut axis and the very low probability of the section being made through the
•Deepest dye penetration point, with the consequences of underestimation
& recording of unreliable data.
87. According to Martin et al. and Ahlberg et al transverse root sectioning
results in loss of part of the dentinal tissue & dye due to the technique itself
and only allows one to determine whether or not there is penetration in
each section.
The clearing technique recommended by Okumura in 1927,in which the
teeth become transparent after a process of demineralisation ,dehydration and
immersion in methyl salicylate ,provides a three dimensional view of the internal
anatomy of root canals without the loss of dentinal substance, making it easier to
view the leakage area.
88. Fluid filtration & trasportation methodology:
• The fluid filtration method ,in which the sealing capacity is measured by means
air bubble movement inside a capillary tube, was developed by Pashley’s group
in 1987 & modified by Wu et al.in 1993 for use in root canals.
• It consist of a filled canal that has its coronal portion connected to a tube filled
with water under atmospheric pressure ,and its apex to a 20 micro L glass capillary
tube 170mm long and of uniform calibre filled with water.
•Finally a pressure of 0.1 atm is applied through the coronal part, which forces
the water through the empty spaces along the root canal .
•The results are generally expressed in micro L/min
89. Dye extraction method:
•In the dye extraction method ,the teeth are dissolved in acids that release all
the dye from the interface and the optical density of the solution is measured
by a spectrophotometer.
•It is fast and can be carried out with equipment available at most universities
•According to Camps,Pashley,there was no correlation between dye penetration,
fluid filtration and dye extraction techniques which determine microleakage.
•The fluid filtration gives similar results to those of dye extraction, because both
take in to consideration the porosity of the interface between the filling
material and the root.
90. Bacteria and toxin infiltration method:
•According to Timpawat et al. The use of bacteria to asses leakage is
considered to be of greater clinical and biological relevance than the
dye penetration method.
•Many different strains of bacteria have been used to assess marginal
leakage and has lead to contradictory results, because the method
depends on type of bacteria used.
•More over, if the sealer has antimicrobial property, it is unfeasible to employ
the bacterial method
•The system generally comprise two chambers and enable the apical and
coronal extremities of each specimen to be completely separated.
•The turbidity of the broth in the apical chamber is the first indication
of contamination by micro organism.
•If the pulp chamber becomes contaminated than root canal treatment
may fail .
91. From the various literature ,it is noted that various methodologies are available
for assessing leakage. Some are simple such as dye penetration, and others are
complex, such as bacterial leakage.
It was found that all the methods are really very technique sensitive, thus the
outcome is variable.
92. Rational for Coronal seal:
•It prevents micro leakage
•Without proper seal it takes only 19 days for staphylococcus penetration
•Bacterial endotoxin could damage the total seal
•
•Prevent exchange of fluids between root canal & oral cavity
•Prevents escaping medications from root canal
94. Double seal→
•Gives tight seal of the coronal restoration
•Prevents ingress of the micro organism in to the root canal after
commencement of the root canal therapy
•Prevents ingress of the fluids & organic materials from oral cavity to
the root canal
•Prevents seepage of the intracanal medicaments
•Provides acceptable aesthetics
•Protect tooth structure during treatment
•Prevents accidental penetration of permanent filling material inside
the root canal
95. ENDODONTICS: Arnaldo castellucci
PATHWAYS OF THE PULP (6th Edition): Stephen Cohen, Richard C. Burns
PRINCIPLES AND PRACTICE OF ENDODONTICS (3RD EDITION): Walton & Torabinejad
ENDODONTIC THERAPY (6th Edition): Franklin S. Weine
INGLE’S ENDODONTICS 6
GROSSMAN’S ENDODONTIC PRACTICE 12TH Edition
SKINNER’S SCIENCE OF DENTAL MATERIALS:Phillips 9th Edition
STURDEVANT’S ART& SCIENCE OF OPERATIVE DENTISTRY 6th Edition
References: