Dental implants have a long history dating back thousands of years. Modern implantology began in the 1950s-60s when Branemark discovered titanium implants could bond irreversibly to bone, termed osseointegration. There are several types of implants but endosseous implants placed directly into the jawbone are most common. Osseointegration occurs in three stages - osteoconduction, de novo bone formation, and bone remodeling. Key factors for successful osseointegration include biocompatibility, implant design, surface, surgical technique, and loading conditions.
This seminar deals with implant-related complications that lead to implant failure.this also discus diagnostic criteria and preventive methods for an implant failure.
This seminar deals with implant-related complications that lead to implant failure.this also discus diagnostic criteria and preventive methods for an implant failure.
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
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
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
Osseointegration, definition, history, process of osseointegration, factors influencing osseointegration, methods for evaluation of osseointegration, failure of osseointegration
Fixed partial dentures transmit forces through the abutments to the periodontium. Failures are due to poor engineering, the use of improper materials, inadequate tooth preparation, and faulty fabrication. Of particular concern to prosthodontist is the selection of teeth for abutments. They must recognize the forces developed by the oral mechanism, and resistance.
Successful selection of abutments for fixed partial dentures requires sensitive diagnostic ability. Thorough knowledge of anatomy, ceramics, the chemistry and physics of dental materials, metallurgy, Periodontics, phonetics, physiology, radiology and the mechanics of oral function is fundamental.
The biological fixation determines the longevity of dental implant treatment. It ensures the long term survival of dental implant. Better the osseointegration,higher will be the survival rate
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
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
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
Osseointegration, definition, history, process of osseointegration, factors influencing osseointegration, methods for evaluation of osseointegration, failure of osseointegration
Fixed partial dentures transmit forces through the abutments to the periodontium. Failures are due to poor engineering, the use of improper materials, inadequate tooth preparation, and faulty fabrication. Of particular concern to prosthodontist is the selection of teeth for abutments. They must recognize the forces developed by the oral mechanism, and resistance.
Successful selection of abutments for fixed partial dentures requires sensitive diagnostic ability. Thorough knowledge of anatomy, ceramics, the chemistry and physics of dental materials, metallurgy, Periodontics, phonetics, physiology, radiology and the mechanics of oral function is fundamental.
The biological fixation determines the longevity of dental implant treatment. It ensures the long term survival of dental implant. Better the osseointegration,higher will be the survival rate
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
Osseointegration/dental implant courses by Indian dental academyIndian dental academy
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.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
CDSCO and Phamacovigilance {Regulatory body in India}NEHA GUPTA
The Central Drugs Standard Control Organization (CDSCO) is India's national regulatory body for pharmaceuticals and medical devices. Operating under the Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, the CDSCO is responsible for approving new drugs, conducting clinical trials, setting standards for drugs, controlling the quality of imported drugs, and coordinating the activities of State Drug Control Organizations by providing expert advice.
Pharmacovigilance, on the other hand, is the science and activities related to the detection, assessment, understanding, and prevention of adverse effects or any other drug-related problems. The primary aim of pharmacovigilance is to ensure the safety and efficacy of medicines, thereby protecting public health.
In India, pharmacovigilance activities are monitored by the Pharmacovigilance Programme of India (PvPI), which works closely with CDSCO to collect, analyze, and act upon data regarding adverse drug reactions (ADRs). Together, they play a critical role in ensuring that the benefits of drugs outweigh their risks, maintaining high standards of patient safety, and promoting the rational use of medicines.
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
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Title: Sense of Smell
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 primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
These lecture slides, by Dr Sidra Arshad, offer a quick overview of the 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 lead (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
6. Describe the flow of current around the heart during the cardiac cycle
7. Discuss the placement and polarity of the leads of electrocardiograph
8. Describe the normal electrocardiograms recorded from the limb leads and explain the physiological basis of the different records that are obtained
9. Define mean electrical vector (axis) of the heart and give the normal range
10. Define the mean QRS vector
11. Describe the axes of leads (hexagonal reference system)
12. Comprehend the vectorial analysis of the normal ECG
13. Determine the mean electrical axis of the ventricular QRS and appreciate the mean axis deviation
14. Explain the concepts of current of injury, J point, and their significance
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. Chapter 3, Cardiology Explained, https://www.ncbi.nlm.nih.gov/books/NBK2214/
7. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
2. HISTORY
• Dental implant history dates back thousands of years and
includes civilizations such as the ancient Chinese, who
4000 years ago inserted bamboo into the jaw bone for
fixed tooth replacements.
• The Egyptians and later physicians from Europe used
ferrous and precious metals for implants over 2000 years
ago, and the Incas used the pieces of sea shells to insert
in jaw bones to replace missing teeth.
3. • A dental implant is defined as shaping a foreign object
to a root and tooth crown form and placing it into an
empty socket or prepared osteotomy of the recipient..
4. The Birth of Modern Implantology
• The true birth of modern implantology, however, can be
found in the late 1950s and 1960s.
• Branemark discovered that the titanium had apparently
bonded irreversibly to the living bone tissue, an
observation which contradicted contemporary scientific
theory of the day..
5. • More importantly, he was able to demonstrate that this
could be achieved with a very high degree of
predictability and, without long-term soft tissue
inflammation, fibrous encapsulation or implant failure.
Branemark named the phenomenon osseointegration.
6. Types of Dental Implants
• Dental implants vary in several aspects, such as shape,
place of anchorage (within the bone or on top of the
bone), composition, coatings, etc.
• In general Oral Implants can be categorized into three
main groups:
– Endosseous Implants
– Subperiosteal Implants
– Transosseous Implants
7. • Endosseous Implants are implants that are surgically
inserted into the jawbone.
• Subperiosteal Implants are implants, which typically lie
on top of the jawbone, but underneath gum tissues. The
important distinction is that they usually do not penetrate
into the jawbone.
8. • Transosseous Implants are implants, which are similar
in definition to Endosseous implants in that they are
surgically inserted into the jawbone.
9. • Endosseous Implants are the most frequently used
implants today. They could be further categorized into
several sub-categories; based on their shape, function,
surgical placement and surface treatment.
10. Subperiosteal Implants
• You can see a typical
Subperiosteal implant for
the lower jaw. This
particular implant has a
whitish-gray
Hydroxyapatite coating
on its bone-contacting
portion.
11. Indications
• Usually a severely resorbed, toothless lower jaw bone,
which does not offer enough bone height to
accommodate Rootform Implants as anchoring devices.
• This implant is custom-made to each individual jaw.
Nowadays, a CT Scan is taken of the jaw and a
computerized modeling machine uses this data to
reproduce a three-dimensional plastic model of the jaw
to be treated.
12. x-ray of a fairly resorbed lower jaw image shows the same jaw with a
Subperiosteal implant in place
13. • After the implant has been
surgically inserted, only a bar
is visible extending from one
side of the lower jaw to the
other, onto which a denture can
be clipped via an internal
attachment mechanism.
• The denture can be made
approximately two weeks after
the surgery and is in general
smaller than a conventional
denture.
16. Blade implant
specifically
designed for the
back-most portion
of the lower jaw.
This implant offers
great anchorage in
that particular area
Custom-made
blade implant
specifically
designed for
the upper jaw
This implant was
specifically and custom-
designed for the lower jaw
of a patient. Notice the
difference in shape to the
upper-jaw implant. These
two implants also feature a
Hydroxyapatite coating
17. Indications
• where the residual bone ridge of the jaw is either too
thin (due to resorption) to place
• Nowadays, if a certain area of the jaw bone is too thin
and has undergone resorption due to tooth loss it is
recommended to undergo a Bonegrafting procedure,
which re-establishes the lost bone, so that conventional
Rootform Implants can be placed.
18. Here you can see an x-ray of a blade implant in place. An important
anatomical structure (mandibular nerve and vessel canal) is outlined in
black underneath. Notice how the implant was placed to avoid injury to
this structure
19. Transosseous Implants
The plate on the bottom is firmly
pressed against the bottom part of the
chin bone, whereas the long screw
posts go through the chin bone, all the
way to the top of the jaw ridge inside
the mouth.
The two attachments that will
eventually protrude through the gums
can be used to attach an overdenture-
type prosthesis.
20. Other Implants
Endodontic stabilizers
• They are placed into the bone through the apices of the
natural teeth.
Intramucosal inserts
• They are buttonlike, non-implanted retention devices that
can be used to stabilize full and partial maxillary and
mandibular removable partial denture prostheses.
24. According to Branemark, Zarb, and Alberktsson (1985)
Osseointegration is defined as structural and
functional connection between ordered living bone and
surface of load carrying implant.
According to American academy of implant dentistry
Osseointegration is the contact established
without interposition of non bone tissue between normal
remodeled bone and an implant entailing a sustained
transfer and distribution of load from implant to and
within the bone tissue.
25.
26. THEORIES OF OSSEONTEGRATION
There are two basic theories regarding bone- implant
interface :
1)Fibro osseous integration supported by Linkow (1970),
2)Osseointegration (James and Weiss (1986) and
Branemark ( 1985)
27. Fibrous- osseous integration
• In 1986, the American academy of implant dentistry
defined it as “tissue to implant contact with healthy
dense collagenous tissue between implant and bone.
• Fibrous osseointegration refers to connective tissue made
of well organized collagen fibers present between bone
and implant. (Meffert 1987)
28. • In this theory collagen fibers functions similar to
Sharpey’s fibers in natural dentition. They are however
different from fibers in periodontal ligament natural
teeth. The fibers are arranged irregularly parallel to
implant surface. When forces are applied, they are not
transmitted through the fibers as seen in natural
dentition.
29. • No Sharpey ‘s fibers are present between bone and
implant so it is difficult to transmit the load. Therefore,
bone remodeling cannot be expected in fibro integration.
• More over the forces applied resulted in widening of
fibrous encapsulation, inflammatory reaction and gradual
bone resorption leading to implant failure.
30. Theory of Osseointegration
• According to Branemark , osseointegration is a
histological definition meaning “ a direct connection
between living bone and load carrying endosseous
implant at the light microscopic level. (Branemark 1969)
• Meffart et al., 1987 redefined and subdivided the term
osseointegration into "adaptive osseointegration and bio-
integratiion.“ Adaptive osseointegration " has the
osseous tissue approximating the implant without
apparent soft tissue interface at the light microscopic
level while Biointegration is a direct biochemical bone
surface attachment confirmed at electron microscopic
level.
31. • Other factors influencing successful osseointegration
include implant oxide layer contamination and poor
temperature control during drilling procedure.
• The oxide layer consist of Tio and Tio2 and Ti2O3,
Ti3O4 and can attract bio molecules. The contaminated
area changes the oxide layer contamination and
inflammatory reaction follows resulting in granulation
tissue formation similar to organization process.
32. • The osseointegration process observed after implant
insertion can be compared to bone fractured healing.
• There is coupling between bone apposition and bone
resorption.
• First woven bone is quickly formed in the gap between
the implant and the bone.
• Second after several months it is replaced by ,lamellar
bone under load stimulation.
• Third a steady stage is reached after about 11/2years
33. • The healing process in this implant system is similar to
primary bone healing. Initially ,blood is present between
fixture and bone, then the blood clot forms. The blood
clot is transformed by phagocytic cells, such as
polymorphonuclear leukocytes, lymphoid cells, and
macrophages.
• The phagocytic activity level peaks during first and third
day after surgery. During this, formation of procallus
occurs, containing fibroblasts, fibrous tissue and
phagocytes.
• The procallus becomes dense connective tissue and
mesenchymal tissue become osteoblasts and fibroblasts.
34. • Osteogenic fibers formed by osteoblasts has a potential
to calcify. The dense connective tissue then forms a
fibrocartilagenous pulley, usually forming between
fixture and bone.
• New bone penetrates and new bone matrix is called bone
callus. This new bone, matures and, increases in its
density and hardness.
• About this time, the prosthesis is attached to the fixture
and with stimulation, bone remodeling occurs. Haversion
bone calcifies becomes dense and homogeneous.
• Occlusal stresses stimulate the surrounding bone to
remodel and osseointegrated fixtures can withstand
masticatory forces.
35. • Junctional epithelium consists of basal cell layer with
basal cells attached by desmosomes . A
hemidesmosomal attachment is seen at the abutment
surface.
• It has both lamina lucida and lamina densa; lamina densa
is attached to the abutment surface.
• The precise attachment mechanism between lamina
densa and abutment is not known yet. However , the
surface oxide layer and hemidesmosomal glycoprotein
are thought to form chemical bond attachment.
36. Mechanism Of Osseointegration
• Osborn and Newsly in 1980 described two different
phenomenas (distance and contact osteogenesis) by
which bone gets integrated with the implant surface.
• Contact osteogenesis involves de novo bone formation
directly on the implant surface.
• Distance osteogenesis is formation of new bone on
surface of existing peri implant bone.
37. • The bone surfaces provide a population of osteogenic
cells that lay down matrix that encroaches the implant.
• An essential observation here is that new bone is not
forming on the implant, but the latter does become
surrounded by the bone. Thus in these circumstances ,
implant surfaces will be partially obscured from bone by
intervening cells.
38. • Distance osteogenesis can be expected in cortical bone
healing since vascular disruption of cortex caused during
the implant site preparation is known to lead to death of
the peri implant cortical bone and its subsequent
remodeling by osteoclasts invasion from the underlying
medullary compartment.
• Initiation of mineralisation of healing bone tissue did not
occur on the implant surface, but bone grew towards the
implant subsequent to the death of the intervening
tissues.
39. • In contrast ,in the process of contact osteogenesis ,new
bone is formed first on implant surface.
40. Stages Of Osseointegration
Osseointegration involves three stages
Stage 1. Osteoconduction
• Following the placement of an implant, wound healing is
initiated. Fibrin, produced as a result of transient blood
clotting at the wound site, adheres to the surface of the
implant, forming a scaffold into which osteogenic cells
derived from undifferentiated connective tissue cells can
migrate.
41. • As healing continues, the fibrin scaffold retracts, making
it critical that the implant surface be able to retain its
fibrin attachment and allow the differentiating
osteogenic cells to reach and remain at the implant
surface.
42. • The mechanical and chemical properties of the implant
surface have a profound influence on osteoconduction
because they)influence the anchorage of the fibrin
scaffold through which osteogenic cells reach the
implant surface.
• A rough implant surface, for example, promotes
osteoconduction by providing both a larger surface area
and sites into which the fibrin can become entangled.
43. Stage 2. De Novo Bone Formation
• De novo bone formation is initiated when the osteogenic
cells have fully differentiated. The four stage process
begins with the secretion of a collagen-free organic
matrix that provides nucleation sites for calcium
phosphate mineralization.
• Following nucleation, calcium phosphate crystal growth
begins at the developing interface, and collagen fiber
assembly is initiated.
44. • In the final stage, the collagen compartment calcifies.
New bone is thus separated from the implant surface by
a layer of non-collagenous bone proteins known as the
cement line.
• Bonding the new bone with the implant occurs by fusion
or micromechanical interlocking of the cement line
matrix with the implant surface.
45. Stage 3. Bone Remodeling
• During remodeling, bone tissue is sculpted by absorption
and deposition, and secondary osteons form. When these
osteons impinge on the implant surface, de novo bone
formation occurs on the transcortical implant.
• Bone remodeling is particularly important for the long-
term stability of the transcortical portion of the implant,
since cortical bone can necrose as a result of surgical
trauma.
46. • This stage leads to functional adaptation of the bony
structures load by changing dimensions and orientations
of supporting elements. (L.J Heitz Mayield,B. Schimd,
C. Weigel. Does excessive occlusal load affect
osseointegration? And experimental study in the dog .
Clin oral implant research 2004 :15 ;1285-89)
47. Key Factors Of Osseointegration
These include
• biocompatibility
• implant design
• implant surface
• implant bed
• surgical technique
• loading conditions