This presentation is all about restoration of endodontically treated teeth, prefabricated post and core, cast post and core, direct and indirect technique.
This presentation is all about restoration of endodontically treated teeth, prefabricated post and core, cast post and core, direct and indirect technique.
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.
Rehabilitation of endodontically treated teeth : Post & CoreNaveed AnJum
These days we often come across mutilated or badly broken teeth in our practice. However various factors are involved for a better prognosis of such a teeth. This presentation mainly focuses on post and core treatment of such a teeth.
Restoration of endodontically treated teeth / dental implant coursesIndian 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.
classification and configuration for fixed partial dentures/dental coursesIndian 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.for more details please visit
www.indiandentalacademy.com
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.
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.for more details please visit
www.indiandentalacademy.com
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.
Rehabilitation of endodontically treated teeth : Post & CoreNaveed AnJum
These days we often come across mutilated or badly broken teeth in our practice. However various factors are involved for a better prognosis of such a teeth. This presentation mainly focuses on post and core treatment of such a teeth.
Restoration of endodontically treated teeth / dental implant coursesIndian 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.
classification and configuration for fixed partial dentures/dental coursesIndian 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.for more details please visit
www.indiandentalacademy.com
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.
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.for more details please visit
www.indiandentalacademy.com
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.
Rationale of post endodontic restoration /certified fixed orthodontic cours...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.
The structure and composition of teeth is perfectly adapted to the functional demands of the mouth and are superior in comparison to any artificial material…So first of all, DO NO HARM.
POST AND CORE RESTORATIONS
CONTENTS
History
Alterations in endodontically treated teeth
Pre Treatment assessment
Definitions and Classifications
Materials Aspects
Biomechanical principles
Historical Update
20th century: the modern face
1960:Core concept
1961: Ferrule concept
1967: Peter Kurer:Kurer post
1970: Baraban: Parapost
1980: Aesthetic Posts
1990: Duret: Composipost
1994: Sandhaus Pasche: zirconia post
2000 : All Ceramic posts
How are endodontically treated teeth different?
Loss of tooth structure results in loss of stiffness
5% in ideal access cavity
40%- for class II
60%- for MOD
Coronal dentin
Stress bearing areas
Radicular dentin removed
Caries, destruction
How are endodontically treated teeth different?
Altered physical characteristics:
Moisture : 9% less (Helfer et al)
Collagen: Decreased (Rivera et al)
14% reduction in strength
Altered esthetic characteristics
Altered light refraction
Degradation of pulp tissue
Medicaments, fillings
Loss of proprioception
Indications: why do we need posts?
Resistance
Retention
PRE TREATMENT ASSESSMENT
Endodontic evaluation
Periodontal evaluation
Restorative evaluation
Esthetic evaluation
Prosthetic evaluation
Endodontic evaluation
Dense uniform three dimensional obturation of the root canal system.
Fluid impervious apical seal.
Periodontal evaluation
Periodontal disease should be treated prior to placement of definitive restorations.
If there is substantial loss of tooth structure, crown lengthening procedures should be considered to maintain the BIOLOGIC WIDTH.
Any destruction in this width leads to resorption of the alveolar crest, which is not desirable.
Biologic width relates to the amount of tooth structure coronal to the osseous crest upto the gingival attachment apparatus. It is about 2.04mm.
Restorative evaluation
Amount of remaining tooth structure
Anatomical position of the tooth
Functional load on tooth
Esthetic evaluation
Must be done before initiation of post endodontic therapy.
Discoloration from gutta percha can be visible in the coronal aspects of root filled teeth.
Tooth coloured posts should be used in anterior regions.
Prosthetic Evaluation
Extent of tooth destruction.
Method and material used in core build up.
Anterior teeth
Minimal damage: no complete coverage
Composite resin, GIC
Moderate to severe damage:
Post n core, full coverage crown
(Smith and Schuman)
Esthetic considerations
Type of canal
Posterior teeth
Require occlusal coverage
Minimal damage
Moderate damage:
Cuspal coverage
Full coverage
Pin retained amalgam
Severe damage
BASIC COMPONENTS OF A POST AND CORE SYSTEM
DEFINITIONS (GPT)
POST/ DOWEL is a relatively rigid, restorative material placed in the root of the non vital teeth. The foremost purpose
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.
The final restoration over an endodontically treated tooth is as important or probably even more important than the actual root canal therapy itself.
The main aim of endodontics and restorative dentistry is to retain the natural teeth with maximal function and pleasing esthetics.The permanency of endodontically involved teeth has been greatly enhanced by continuing developments made in endodontic therapy and restorative procedures including the use of intraradicular devices.
These devices vary from a conventional custom cast post and core to one visit techniques, using commercially available prefabricated post systems.
These systems are being discussed in this E-content.
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.for more details please visit
www.indiandentalacademy.com
A broad idea about Esthetic Crown objectives and their Indications along side with the drawbacks of SSC also the Classification of esthetic crowns plus the Pros and cons of each esthetic crown.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
263778731218 Abortion Clinic /Pills In Harare ,ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group of receptionists, nurses, and physicians have worked together as a teamof receptionists, nurses, and physicians have worked together as a team wwww.lisywomensclinic.co.za/
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
2. • Introduction
• History
• Definitions
• Why to restore endodontically treated
teeth
• Post & core systems
• Principles of tooth preparation
Contents
3. • Procedure
Post fabrication & Core fabrication
Investing and casting
Evaluation & cementation
• Removal of existing posts
• Conclusion
• References
7. History
1747 Pierre Fauchard
Posts fabricated of gold or silver.
Heat softened adhesive called “mastic
Longevity 15-20 years
Bone, ivory, animal teeth, natural
tooth crowns
Porcelain
8. History
“Pivot crown”.
Early pivot crowns – seasoned wood
Wood posts -“Morbid humors”.
1747 Pierre Fauchard
1800’s – Porcelain pivot crown
Dubois de chemant
1878 Richmond crown
1 piece dowel and crown
Post and Core
9. Definitions
• Dowel (Post):
The dowel is a metal post or other rigid
restorative material placed in the
radicular portion of a non vital tooth.
A dowel usually made of metal is fitted in to a
prepared canal of a natural tooth. When combined
with an artificial crown or core, it provides retention
and resistance for the restoration.
(Glossary of Prosthodontics)
10. • Core:
Refers to properly shaped and well
substructure, which replaces
missing coronal structure and
retains the final restoration.
A centre or a base of a structure. The core is
designed to resemble or become the crown
preparation or crown itself.
(Glossary of Prosthodontics)
11. • Ferrule (Rosenstile):
Is defined as a metal band that
encircles the external dimension of
the residual tooth.
• Ferrule (Weine) :
A ferrule is a metal ring or cap placed
around the end of a cane or tool, giving it
added strength. The ferrule around the
circumference of the tooth strengthens it by
increasing resistance to wedging forces.
12. As prosthodontist – abutment for FPD , RPD, Over denture
As a Restorative dentist -Increase the clinical longevity of
these teeth.
Schwartz et al 1983 found that the failure rate of endodontically treated
teeth was almost double in cases with inadequate restoration.
Weine 1996 more endodontically treated teeth are lost due to poor
restoration than to subsequent endodontic failure.
Why to Restore ?
16. Restorative evaluation
The amount of remaining tooth structure.
The anatomical position of the tooth.
The functional load on the tooth.
The aesthetic requirements of the tooth.
17. The amount of remaining tooth structure
Anterior teeth
Do not need posts and full coverage crowns
Anterior teeth are inclined at an angle to the occlusal plane
Sound tooth with access
opening
Lack of Coronal tooth
structure
18. Posterior teeth
Carry greater occlusal loads
Minimal occlusal access preparations
Teeth with existing restorations involving the marginal ridge or
those with extensive loss of tooth structure
Where ever possible posts should be avoided in posterior teeth
as the roots are often narrow and or curved
20. Ideal properties of a post
Maximum protection to root
Adequate retention within root
Maximum retention of the core and the crown.
Maximum protection of the crown
margin cement seal
Pleasing esthetics when indicated
High radiographic visibility
Retreivability
Biocompatibility
21. • Classification of posts ( D C N A 2002 )
Metallic Non Metallic
Custom cast posts
Prefabricated
Carbon fiber posts
Zirconia posts
Woven fiber composite post
22. Multiple cores- in the same arch
Small teeth
Angle of cores – to be changed
All – ceramic crown
- PGP [platinum-gold- palladium]
- Nickel –chromium
- Cobalt - chromium
- Stainless steel
- Non oxidizing noble alloys
- Au-pt
- Titanium
Custom cast posts :
• Metallic Posts
Indication
combinations
23. Pre- fabricated posts :
Tapered posts :
Mimics natural canal shape
Least amount of retention
Parallel posts :
provides greater retention
Active posts
Indicated :
in short canal space
Passive
24. Carbon fibre posts
Bundles of stretched aligned carbon fibers embedded in
an epoxy matrix
Modulus of elasticity similar to dentine
Unesthetic
Radiolucent
Can bond to dentine
Purton et al 1996
Millstein et al 1999
Bond strength of composite core material to
CFP < Composite core to metal post.
• Non-Metallic Posts
25. Trido et al 1999
Bond strength can be increased by air abrasion of CFP.
Drummond et al 1999 :
Stockson et al 1999 :
Retention of CFP = Metal posts.
Found decrease in bond strength after air abrasion.
Carbon fibre posts
26. Tooth coloured posts :
Zirconium coated CFP
Aesthetic post plus ( Bisco )
All zirconium posts (Cosmoposts & ceraposts )
Fibre reinforced posts
Light post ( Bisco )
Luscent anchor ( Dentatus )
Fibrekor posts
Zirconium posts modulus of elasticity > Stainless steel
lower fracture resistance than metal posts & inability to bond.
Difficult to retrive
27. Resintritt et al in 2000 compared # strength
Titanium post & composite core
&
Zirconium post & composite core
↨ Vectris resin post & composite Core
↨ Custom cast gold post & core
↓ IPS Empress & All Zirconium
28. CORE
Steven M. Morgano & Susan E. Brackett 1999
Desirable features of a core material :
Adequate compressive strength
Sufficient flexural strength
Biocompatibility
Resistance to leakage of oral fluids at the core/tooth interface.
Ease of manipulation.
Ability to bond to remaining tooth structure
Thermal co-efficient of expansion and contraction
Dimensional stability
Minimal potential for water absorption &
Inhibition of dental caries.
29. Classification of core materials :
Cast core Plastic core materials
Metal
Ceramic to Zirconia
dowels
Amalgam
Glass ionomer cement
Resin modified GIC
Dual cure fibre reinforced cores
30. Pissis 1995 proposed a “Monobloc” technique for fabrication of a
post and core and a crown as a single component made out of glass
ceramic material IPS empress.
Kantor and pines 1977 teeth little coronal structure the cast gold
post and core was superior to a stock post and composite resin core.
Cast core
Ceramic to Zirconia dowels
31. Hoag ED, Dwyer TG 1982 Amalgam can be used for core build
ups Due to its self – sealing proprieties, durability and good
working characteristics
Nayyar, Walton, Leonard 1980 reported a technique of
amalgam core build up
Amalgam
32. Barban 1970 was one of the first to suggest the use of
composite resin to fabricate cores.
Linde LA 1983 found that composite cores showed significantly
greater marginal leakage compared with amalgam cores.
MC lean 1985 GIC can be tooth substance remains and where
limited loading is anticipated.
Resin modified GIC not recommended in high stress situations.
34. • Conservation of tooth structure
Preparation of the canal
Preparation of coronal tissue
• Retention form
Anterior teeth
Posterior teeth
• Resistance form
Stress distribution
Rotational resistance
35. • Remove minimal tooth structure form the canal.
• Excessive enlargement can perforate or weaken the root
~ Thickness of remaining dentin – Fracture resistance from
Preparation of the canal :
Helfer AR et al 1972. teeth cemented with thicker posts (1.8 mm)
fractured more easily than those with a thinner (1.3 mm) one.
Photo elastic studies also have show that internal stresses are
reduced with thinner posts.
Conservation of tooth
structure
36. Root canal should be enlarged only enough to enable the post
to fit accurately yet passively while insuring strength and
retention.
Felton DA 1991 said that most root fractures originate from these
concavities because the remaining dentin thickness is minimal.
Most roots have proximal concavities
37. Preparation of coronal tissue :
Milton P and Stein R S 1992 if more than 2 mm of coronal
tooth structure remains, the post design probably has a limited
role in the fracture resistance of restored tooth.
A key element of tooth preparation when using a dowel and core is
the incorporation of a ferrule.
38. A ferrule is a metal band or ring used to fit the root or crown of a tooth.
CERVICAL FERRULE
• Increased fracture resistance
• Antirotational
41. The effectiveness of the ferrule has been evaluated by a variety
of methods, including
Fracture testing
Impact testing
Fatigue testing and
Photo elastic analysis.
1.5 mm of ferrule height
Philip et al 2005 have investigated the resistance to static loading of
endodontically treated teeth with uniform and non uniform ferrule
configuration
2 mm uniform > 0.5 – 2mm ferrule height non uniform
2 mm uniform &
0.5 – 2mm ferrule height non uniform
NO ferrule>
42. what if tooth has inadequate coronal tooth structure to
create a ferrule ?
Surgical :Crown lengthening
Allows ferrule
Less favourable crown root ratio
increased leverage on the root during function
Gegauff 1999: showed that creating ferrule through crown
lengthening resulted in a weaker rather than a stronger restored tooth.
Orthodontic extrusion
•Consider crown lengthening and or extrusion
43. Anterior teeth
Preparation geometry
Post length & diameter
Surface texture and
Luting agent.
Retention form
Post retention is affected by the
44. Preparation geometry :
Elliptical cross section
Must be prepared with restricted amount of taper 6-8
Taper increases – retention decreases similar to extra coronal
preparation.
Canals
Circular cross section
Prepared with a twist drill or reamer to provide a cavity with
parallel walls or minimal taper.
45. Standlee JP et al 1978 confirmed that parallel sided posts more
retentive than tapered posts and that threaded posts are most
retentive.
Increase the retention
Not recommended because of residual stress in dentin.
Threaded posts :
46. Studies have shown that an post length increases, so does
retention. However the relationship is not linear.
A post that is too short will fail
Ideally, as long as possible 5 mm apical seal
not les than 3 mm
Post length :
Post that is too long
47. Post diameter :
Increasing the post diameter in an attempt to increase retention
Ideally
No wider 1/3 root
2 mm of tooth structure.
Tilk M A et al 1979 :1500 teeth (125 of each tooth)
0.6 mm – Mandibular incisors
1.0mm – Maxillary CI, Max and Man canines,
Palatal root of max I molar
0.8 mm Other teeth.
48. Shillingburg et al 1982 in a study of 100 teeth
0.7 mm – Mandibular CI
1.7 mm – Maxillary CI.
49. 4) Post surface texture :
A serrated or roughened post is more retentive than a smooth one.
Controlled grooving of the post and root canal increases the
retention of a tapered post.
5) Luting agent :
Traditional cements – little effect
Adhesive resin luting cements – increased retention
Note: irrigation with ethanol or etching with 37% phosphoric acid
50. Long posts avoided – curved roots and elliptical or ribbon shaped
canals.
Retention is better provided by two or more relatively short posts
in the divergent canals.
Cast core can be used (made in sections that have different paths
of with drawl).
Posterior teeth :
51. Stress distribution
Photo elastic materials.
Strain gauges and
Finite elements analysis
The greatest stress concentrations are found at the shoulder,
particularly interproximally, and at the apex.
Resistance form
The influence of post design on stress distribution has been
tested using.
52. Stresses are reduced as post length increases.
Sharp angles should be avoided because they produces high
stresses during loading
High stress can be generated during insertion, parallel sided posts
Parallel sided posts Tapered posts
53. Threaded posts
Rotational resistance :
Rotation can be prevented by vertical coronal wall.
a small groove placed in the canal
root is bulkiest – lingual aspect
Backed off a half turn
Cement layer
55. 1. Removal of the root canal filling material to the appropriate depth.
2. Enlargement of the canal
3. Preparation of the coronal tooth structures
3 stage operation.
58. 1.REMOVAL OF THE ENDODONTIC FILLING
MATERIAL1. Chemical Removal
2. Thermal Removal
3. Mechanical Removal
Schnell FJ 1978 and Bourgeois R S and Lemon RR (1981)
gutta-percha can be removed with a warm condenser immediately
after obturation.
Dickey DJ et al 1982 Rotary instrument can disturb
apical seal if used immediately after obturation.
59. Steps in removal of gutta-percha & Enlargement of the canal
IF gutta-percha is old and has lost its thermoplasticity, use a
rotary instrument (Peeso-Reames or Gates Glidden drills)
Before enlargement of the canal, the type of post system to
be used for fabrication of the post and core must be chosen.
Calculate the appropriate length of the post
60. 2.PREPARATION OF THE CORONAL
TOOTH STRUCTURE :
Remove all internal and external undercuts
Complete the preparation by eliminating sharp angles
and establishing smooth finish lines.
prepared perpendicular to the post, to create a positive stop & to
prevent over seating and splitting of the tooth.
If insufficient tooth structure remains for this feature, an
antirotation groove should be placed in the canal
66. Indirect procedure :
Pieces of orthodontic wire
Lubricate the canals
a lentulo spiral
syringe in impression material
Apply a thin coat sticky wax to the plastic post
after lubricating the stone cast,
add soft inlay wax in increments
Investing and casting
67. INVESTING AND CASTING
Casting should be slightly undersized
Cast post-and-core should fit somewhat loosely in the canal
Omitting the usual ring liner or
Casting at lower mold temperature
Extra-hard partial denture gold (ADA type IV) or
nickel chromium alloys
EVALUATION :
Casting defects should not interfere with
seating of the post; otherwise, root fracture
will result.
68. Post-and-cores should be inserted with gentle pressure
CEMENTATION :
A rotary (lentulo) paste filler or cement tube
a parallel-sided post is being used, a groove should
be placed along the side of the post
70. Removal of existing posts :
Thin-beaked forceps
Ultrasonic removal
Post puller
Special hollow end-cutting tubes (or trephines)
Drilled out
Masserann kit
If the fractured post is of the threaded type a groove cut in the end
of it may enable it to be unscrewed
73. R
E
F
E
R
E
N
C
E
S
7. Harold Gerstein, "Technique In Clinical Endodontics" 347-
87.
8. Pitt Ford, "Problem-solving in Clinical Practice" 149-164.
9. Gutmann, "Problem-solving in Endodontics" 3rd Edn, 325-
46.
10.Stephen Cohen, "Pathways of the Pulp", 8th Edn, 765-795.
11. Franklin S. Weine, "Endodontic Therapy" 4th Edn, 653-
698.
12. Tylman's "Theory and Practice's of Fixed Prosthodontics",
8th Edn, 407-417.
13. Herbert T. Shillingburg, "Restoration of the Endodontically
Treated Tooth" 1982Edn. .
14. Herbert Shillingburg, "Fundamental of Fixed
Prosthodontics" 3rd Edn, 194-209.
15. Herbert Shillingburg, "Fundamental of Tooth Preparation"
2nd Edn, 321-358.
16. Rosensteil, "Contemporary Fixed Prosthodontics" 3rd
Edn., 272-312.
17. Endod Dent Traumatel1998; 14: 59-63.