PHYSICAL PROPERTIES
CHEMICAL PROPERTIES
STRUCTURE OF ENAMEL
DEVELOPMENT OF ENAMEL
EPITHELIAL ENAMEL ORGAN
AMELOGENESIS
LIFE CYCLE OF AMELOBLASTS
AGE CHANGES IN ENAMEL
DEFECTS OF AMELOGENESIS
CLINICAL IMPLICATIONS
It is a presentation in detail about the strongest structure of the oral cavity "ENAMEL". It is a simple topic but people find it difficult to learn about it. I hope my presentation is a simple method to learn about it. I would like to thank my professors for assign me this project and i learn't a lot from it and still learning my basics daily.
Amelogenesis is the formation of enamel. During amelogenesis, the ameloblast (enamel-forming cells) undergo various stages i.e the life cycle of ameloblast.
For more content check out my blog: www.rkharitha.wordpress.com "a little about everything dental"
It is a presentation in detail about the strongest structure of the oral cavity "ENAMEL". It is a simple topic but people find it difficult to learn about it. I hope my presentation is a simple method to learn about it. I would like to thank my professors for assign me this project and i learn't a lot from it and still learning my basics daily.
Amelogenesis is the formation of enamel. During amelogenesis, the ameloblast (enamel-forming cells) undergo various stages i.e the life cycle of ameloblast.
For more content check out my blog: www.rkharitha.wordpress.com "a little about everything dental"
I prepared this presentation during the first year of my MDS. This will give you a basic idea and necessary information about the pulp of the teeth and its histology. Hope you guys find it useful.
An odontoblast is a biological cell of neural crest origin whose main function is formation of dentin.
This slide gives a detailed explanation of the same.
Coronal and radicular pulp
Apical foramen
Accessory canal
Functions of dental pulp
Components of dental pulp
Functions of pulpal extracellular matrix
Organization of cells in the pulp
The principle cells of the pulp
The pathways of collagen synthesis
Matrix and ground substances
Vasculature and lymphatic supply
Innervation of Dentin- pulp complex
Disorders of the dental pulp
Advances in pulp vitality testing
I prepared this presentation during the first year of my MDS. This will give you a basic idea and necessary information about the pulp of the teeth and its histology. Hope you guys find it useful.
An odontoblast is a biological cell of neural crest origin whose main function is formation of dentin.
This slide gives a detailed explanation of the same.
Coronal and radicular pulp
Apical foramen
Accessory canal
Functions of dental pulp
Components of dental pulp
Functions of pulpal extracellular matrix
Organization of cells in the pulp
The principle cells of the pulp
The pathways of collagen synthesis
Matrix and ground substances
Vasculature and lymphatic supply
Innervation of Dentin- pulp complex
Disorders of the dental pulp
Advances in pulp vitality testing
Slides do curso avançado de atualização em implante de Anel de Ferrara, elaborado por Ferrara Ophtalmics. Para material completo, acesse www.aneldeferrara.com.br
Upload By : Ahmed Ali Abbas
Babylon University College of Dentistry
download this file from Website on google theoptimalsmile.wix.com/dentistry
Oral histology
Definition
General properties
Composition
Function of saliva
Formation of saliva
Method for collecting saliva
Advantages
Limitations
Analysis of saliva done for the diagnosis of systemic disease
Definition:
by Stedmann’s & Lipincott medical dictionary.
A clear, tasteless, odourless, slightly acidic (pH 6.8) viscous fluid, consisting of the secretion from the parotid, sublingual, submandibular salivary glands and the mucous glands of the oral cavity.
General properties
Volume: 1000 to 1500 mL of saliva is secreted per day and, it is approximately about 1 ml/ minute.
Contribution by each major salivary gland is:
i. Parotid glands: 25%
ii. Submandibular glands: 70%
iii. Sublingual glands: 5%.
Reaction: Mixed saliva from all the glands is slightly acidic with pH of 6.35 to 6.85.
Specific gravity: It ranges between 1.002 and 1.012.
Tonicity: Saliva is hypotonSalivary flow
The average person produces approximately 0.5 L – 1.5 L per day
Unstimulated Flow (resting salivary flow―no external stimulus)
Typically 0.2 mL – 0.3 mL per minute
Stimulated Flow (response to a stimulus, usually taste, chewing, or medication [eg, at mealtime])
Typically 1.5 mL – 2 mL per minute
INTRODUCTION
Tongue is a muscular organ
Situated in the floor of the mouth
FUNCTION
Taste
Speech
Mastication
Deglutition
EXTERNAL FEATURES
Tongue has
A Root
A tip
A body
ROOT
Is attached to the mandible and soft palate above and hyoid bone below.
These attachments prevent the swallowing of the tongue.
In between the 2 bones it is related to the geniohyoid and mylohyoid muscles.
TIP
Of the tongue forms the anterior free end which lies behind the upper incisor teeth.
BODY
Has
A curved upper surface or dorsum
An inferior or ventral surface MUSCLES OF THE TONGUE
Middle fibrous septum divides the tongue into right and left halves.
Intrinsic muscles
Superior longitudinal
Inferior longitudinal
Transverse
Vertical
Extrinsic muscles
Genioglossus
Hyoglossus
Styloglossus
Palatoglossus
Central face begins to develop by 4th week, when olfactory placodes appear on both sides of the frontonasal process.
Gradually both placodes develop to form the median and lateral nasal process.
Upper lip is formed by 6th week by fusion of two median nasal processes in midline and the maxilllary process of the 1st branchial arch.
PRE-NATAL GROWTH AND DEVELOPMENT OF PALATEFormation of primary and secondary palate
Elevation of palatal shelves
Fusion of palatal shelves
Introduction
Epidemiology
Etiology
Manifestations
TNM staging
Squamous cell carcinoma is defined as malignant epithelial neoplasm exhibiting squamous differentiation as characterised by the formation of keratin and/or the presence of intercellular bridges.
( Pindborg et al, 1997).
Occipital (2-4)
Superior nuchal line between sternocleidomastoid and trapezius
Occipital part of scalp
Superficial cervical lymph nodes
Accessary lymph nodes
Mastoid (1-3)
Superficial to sternocleidomastoid insertion
Posterior parietal scalp
Skin of ear, posterior external acoustic meatus
Superior deep cervical nodes Accessary lymph nodes
Preauricular (2-3)
Anterior to ear over parotid fascia
Drains areas supplied by superficial temporal artery
Anterior parietal scalp
Anterior surface of ear
Superior deep cervical lymph nodes
Parotid (up to 10 or more)
About parotid gland and under parotid fascia
Deep to parotid gland
External acoustic meatus
Skin of frontal and temporal regions
Eyelids, tympanic cavity
Cheek, nose (posterior palate)
Superior deep cervical lymph nodes
Facial
Superficial(up to 12)
Maxillary
Buccal
Mandibular
Distributed along course of facial artery and vein
Skin and mucous membranes of eyelids, nose, cheek
Submandibular nodes
Deep
Distributed along course of maxillary artery lateral to lateral pterygoid muscle
Temporal and infratemporal fossa
Nasal pharynx
Superior deep cervical lymph nodesSuperficial
Anterior jugular vein between superficial cervical fascia and infrahyoid fascia
Skin, muscles, and viscera of infrahyoid region of neck
Superior deep cervical lymph nodes
Deep
Between viscera of neck and investing layer of deep cervical fascia
Adjoining parts of trachea, larynx, thyroid gland
Superior deep cervical lymph nodes
Anterior cervical/Superficial
Submental (2-3)
Submental triangle
Chin
Medial part of lower lip
Lower incisor teeth and gingiva
Tip of tongue
Cheeks
Submandibular lymph node to jugulo-omohyoid lymph node and superior deep cervical lymph nodes
Is a phenomenon of reflex sequence of muscle contractions that propels the ingested materials and pooled saliva from the mouth to the stomach.
PATTERNS
Infantile (visceral) swallow
Adult/mature swallow
ADULT SWALLOWING
Is composed of 4 stages
Voluntary
Preparatory phase
Oral or buccal
Involuntary: Controlled By Medulla and Lower Pons
Pharyngeal
b. Oesophageal
• Function
• External features
• Papillae of tongue
• Muscles of the tongue
• Arterial supply
• Venous drainage
• Lymphatic drainage
• Nerve supply
• Histology
• Development of tongue -
Intrinsic muscles
Superior longitudinal
Inferior longitudinal
Transverse
Vertical
- Extrinsic muscles
Genioglossus
Hyoglossus
Styloglossus
Palatoglossus
1. Vallate or circumvallate papillae
These are large in size 1-2mm in diameter and are 8-12 in number.
They are situated immediately in front of the sulcus terminalis.
Each papillae are cylindrical projection surrounded by a circular sulcus.
The walls of the papilla are raised above the surface.
2. Fungiform papillae
Are numerous
Near the tip and margins of the tongue, but some of them are scattered over the dorsum.
These are smaller than the vallate papillae but larger than the filliform papillae.
Each papilla consists of a narrow pedicle and a large rounded head.
They are distinguished by their bright red colour.
3. Filliform papillae
Conical papilla
Cover the presulcal area of the dorsum of the tongue and gives it a characteristic velvety appearance.
They are the smallest and most numerous of the lingual papillae.
Each are pointed and covered with keratin
The apex is often split into filamentous processes.
Fifth cranial nerve
Have a large sensory root and a small motor root.
Motor root arises – arises from the lateral aspect of lower pons (cranially) the motor root cross the apex of the petrous temporal bone beneath the superior petrosal sinus, to enter the middle cranial fossa.
Sensory root – arises from the lateral aspect of lower pons (caudally).
RELATIONS
Medially
(a) internal carotid artery
(b) posterior part of cavernous sinus
Laterally - middle meningeal artery
Superiorly - parahippocampal gyrus
Inferiorly
motor root of trigeminal nerve
(b) greater petrosal nerve
(c) apex of the petrous temporal bone
(d) foramen lacerum.OPTHALIMIC DIVISION
Terminal branches of Ophthalmic division of trigeminal nerve, are
1. Frontal
Supratrochlear
Supraorbital
2. Nasociliary
Branch of ciliray ganglion
2-3 long ciliary nerves
Posterior ethmoidal
Infratrochlear
Anterior ethmoidal
3. Lacrimal
Branches
From main trunk
Meningeal branch
Nerve to medial pterygoid
From the anterior trunk
Sensory branch
Buccal nerve
Motor branch
Masseteric
Deep temporal nerve
Nerve to lateral pterygoid
From the posterior trunk
Auriculotemporal
Lingual
Inferior alveolar nerves
COTTON-WOOL APPEARANCE
Active phase showing disorganised bone architecture with numerous, large, multinucleated osteoclasts. The stroma is vascular and fibrous
The late phase features thick trabeculae with a prominent mosaic pattern of prominent, hematoxyphilic, cement lines at the interfaces of episodes of resorption followed by deposition.
Paget disease showing very prominent blue cement lines. The lamellae are arranged haphazardly giving an overall effect of a jigsaw puzzle.
Hume- “caries is essentially a progressive loss by acid dissolution of the apatite component of the enamel then the dentin or of the cementum then dentin.”
According to location:
Pit or Fissure caries
Smooth Surface caries
According to rapidity:
Acute
Chronic
Arrested
According to occurrence:
Primary (Virgin) caries
Secondary (Recurrent) caries
According to the site of occurrence:
Enamel caries
Cemental caries.
Acidogenic [ Miller’s Chemico-parasitic] theory.
Proteolytic theory.
Proteolysis- chelation theory.
The lymphatic system has three functions:
Fluid recovery.
Immunity
Lipid absorption
The lymphatic vessels of the small intestine receive the special designation of lacteals or chyliferous vessels.
The components of the lymphatic system are :-
lymph, the recovered fluid;
Lymphatic vessels, which transport the lymph;
Lymphatic tissue, composed of aggregates of lymphocytes and macrophages that populate many organs of the body; and
Lymphatic organs, in which these cells are especially concentrated and which are set off from surrounding organs by connective tissue capsules.
A Magnified Microscopic Image Is Worth More Than A Thousand Words.
DARK FIELD MICROSCOPE
PHASE CONTRAST MICROSCOPY
POLARIZED LIGHT MICROSCOPY
FLUORESCENT MICROSCOPY
STEREO MICROSCOPE
ELECTRON MICROSCOPY
Maxillary Second Premolar
the maxillary first premolar in function
Less angular ,rounded crown in all aspects.
Single root
Smaller crown cervico occlusally
Root length is as great or greater
BUCCAL ASPECT
Not as long as that of the first premolar
Less pointed
Mesial slope is
shorter than the distal slope
Buccal ridge of the crown may not be so prominent whencompared with the first premolarLINGUAL ASPECT
Lingual cusp is longer making the crown longer on the lingual sideMESIAL ASPECT
Cusps of second premolar are shorter with the buccal and lingual cusps more nearly the same length
Greater distance between cusp tips-that widens the occlusal surface buccolingually
No developmental depression on the mesial surface of the crown as on the first premolar
Crown surface is convex instead
No deep dev. Groove crossing the mesial marginal ridgeOCCLUSAL ASPECT
Outline of the crown is more rounded or oval rather than angular
Central dev. groove is shorter and more irregular
Tendency toward multiple supplementary grooves radiating from the central groove that may extend out to the cusp ridges
Makes for an irregular occlusal surface and gives a very wrinkled appearance
Centered in the maxilla, one on either side of median line, with mesial surface of each in contact with mesial surface of other
Two in number
Larger than the lateral incisor
These teeth supplement each other in function, and they are similar anatomically
Shearing or cutting teeth
Major function is to punch and cut food material during the process of mastication
These teeth have incisal ridges or edges rather than
cusps such as are found on canines & posterior teeth
First evidence of calcification
Crown completion
Eruption
Root completion
3-4 months
4-5 years
7-8 years
10-11 years
PRENATAL GROWTH OF MANDIBLE
Occurs between the 4th and 7th week of intrauterine life.
4th week of intrauterine life
Formation of the head fold
Following which the developing brain and the pericardium form 2 prominent bulges on the ventral aspect of the embryo.
The 2 bulges are separated from each other by a shallow depression called stomatoedum (corresponding to the primitive mouth).
Floor of the stomatodeum is formed by the Buccopharyngeal membrane, which separates the stomatodeum from the foregut.Soon, mesoderm covering the developing forebrain proliferates, and forms a downward projection that overlaps the upper part of the stomatodeum – this downward projection is called frontonasal process.
Since the formation of various parts of the face involves fusion of diverse components.
Occasionally this fusion can be incomplete give rise to various anomalies
MANDIBULOFACIAL DYSOSTOSIS OR FIRST ARCH SYNDROME
- Entire first arch may remain underdeveloped on one or both sides, affecting
Lower eyelid
Maxilla
Mandible
External ear.
- Prominence of the cheek is absent
- Ear is displaced ventrally and caudally
Face develops in humans between 4th – 10th week of intrauterine life.
prenatal growth of the maxilla
DEVELOPMENT OF UPPER LIP
Development of lower lip
Development of nose
hare lip
OBLIQUE FACIAL CLEFT
macrostomia
lateral facial cleft
microstomia
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
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
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
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!
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.
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.
Follow us on: Pinterest
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
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
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.
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.
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.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
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
Ocular injury ppt Upendra pal optometrist upums saifai etawah
ENAMEL
1. ENAMELENAMEL
DR AMITHA G, BDS, MDSDR AMITHA G, BDS, MDS
ORAL AND MAXILLOFACIAL PATHOLOGYORAL AND MAXILLOFACIAL PATHOLOGY
2. CONTENTSCONTENTS
INTRODUCTIONINTRODUCTION
PHYSICAL PROPERTIESPHYSICAL PROPERTIES
CHEMICAL PROPERTIESCHEMICAL PROPERTIES
STRUCTURE OF ENAMELSTRUCTURE OF ENAMEL
DEVELOPMENT OF ENAMELDEVELOPMENT OF ENAMEL
EPITHELIAL ENAMEL ORGANEPITHELIAL ENAMEL ORGAN
AMELOGENESISAMELOGENESIS
LIFE CYCLE OF AMELOBLASTSLIFE CYCLE OF AMELOBLASTS
AGE CHANGES IN ENAMELAGE CHANGES IN ENAMEL
DEFECTS OF AMELOGENESISDEFECTS OF AMELOGENESIS
CLINICAL IMPLICATIONSCLINICAL IMPLICATIONS
3. INTRODUCTIONINTRODUCTION
Hardest biological tissue
present
as outer most covering of the
crown.
Epithelial derived hard tissue
, formed by ameloblasts
which cannot be reform
itself.
Non vital as it is acellular ,
avascular.
4. PHYSICAL PROPERTIESPHYSICAL PROPERTIES
TRANSLUCENT TISSUE .TRANSLUCENT TISSUE .
YELLOWISH WHITE TO GRAYISH WHITE.YELLOWISH WHITE TO GRAYISH WHITE.
THICKNESS VARIESTHICKNESS VARIES
HARDNESS – 296KHNHARDNESS – 296KHN
BRITTLEBRITTLE
SPECIFIC GRAVITY – 2.8SPECIFIC GRAVITY – 2.8
DENSITY- 2.8 TO 3.0 GM/SQ.CMDENSITY- 2.8 TO 3.0 GM/SQ.CM
SEMI- PERMEABLESEMI- PERMEABLE
7. ENAMEL RODSENAMEL RODS
ENAMEL CONSISTS OF RODS, ROD SHEATH AND INTER-ENAMEL CONSISTS OF RODS, ROD SHEATH AND INTER-
ROD ENAMEL.ROD ENAMEL.
5 MILLION (MAND LATERAL) TO 12 MILLION (MAX FIRST5 MILLION (MAND LATERAL) TO 12 MILLION (MAX FIRST
MOLAR)MOLAR)
TORTUOUS COURSE FROM DEJ TO OUTER SURFACETORTUOUS COURSE FROM DEJ TO OUTER SURFACE
DIAMETER - DEJ :OUTER SURFACE - 1:2DIAMETER - DEJ :OUTER SURFACE - 1:2
BREADTH – 5UM , LENGTH – 2.5 MMBREADTH – 5UM , LENGTH – 2.5 MM
12. INCREMENTAL LINES OF RETZIUSINCREMENTAL LINES OF RETZIUS
• APPEAR AS BROWNISH BANDS IN GROUND SECTIONS OF ENAMELAPPEAR AS BROWNISH BANDS IN GROUND SECTIONS OF ENAMEL
• REPRESENTS INCREMENTAL DEPOSITION OF THE ENAMEL, I.E.REPRESENTS INCREMENTAL DEPOSITION OF THE ENAMEL, I.E.
SUCCESSIVE APPOSITION OF LAYERS OF ENAMEL.SUCCESSIVE APPOSITION OF LAYERS OF ENAMEL.
• REPRESENT WEEKLY RHYTHM.REPRESENT WEEKLY RHYTHM.
14. SIGNIFICANCESIGNIFICANCE
THESE LINES BECOME PROMINENTTHESE LINES BECOME PROMINENT
DURING CARIOUS ATTACKS.DURING CARIOUS ATTACKS.
REFLECT VARIATION IN STRUCTUREREFLECT VARIATION IN STRUCTURE
AND MINERALIZATION DURING GROWTH.AND MINERALIZATION DURING GROWTH.
HELPS IN CHRONOLOGICAL MAPPINGHELPS IN CHRONOLOGICAL MAPPING
OF DENTAL DEVELOPMENTOF DENTAL DEVELOPMENT
15. STRIATIONSSTRIATIONS
DARK TRANSVERSE LINES SEEN CROSSING THE ENAMEL GIVING ADARK TRANSVERSE LINES SEEN CROSSING THE ENAMEL GIVING A
STRIATED APPEARANCE TO THE ENAMEL RODS.STRIATED APPEARANCE TO THE ENAMEL RODS.
REPRESENTS DAILY INCREMENTS OF GROWTH DURING ENAMELREPRESENTS DAILY INCREMENTS OF GROWTH DURING ENAMEL
FORMATION.FORMATION.
RATE OF ENAMEL FORMATION IS APPROX. 4 UM/DAY.RATE OF ENAMEL FORMATION IS APPROX. 4 UM/DAY.
16. NEONATAL RING OR NEONATAL LINESNEONATAL RING OR NEONATAL LINES ::
• ACCENTUATED INCREMENTALACCENTUATED INCREMENTAL
LINE OF RETZIUSLINE OF RETZIUS
• BOUNDARY BETWEEN PRE-BOUNDARY BETWEEN PRE-
NATAL AND POST-NATALNATAL AND POST-NATAL
ENAMELENAMEL
• USUALLY SEEN IN THEUSUALLY SEEN IN THE
DECIDUOUS TEETH ANDDECIDUOUS TEETH AND
PERMANENT FIRST MOLARS.PERMANENT FIRST MOLARS.
PRENATAL ENAMEL POSTNATAL ENAMEL
NEONATAL LINE
17. HUNTER SCHREGER BANDSHUNTER SCHREGER BANDS ::
OPTICAL PHENOMENONOPTICAL PHENOMENON
PRODUCED BYPRODUCED BY
CHANGE IN DIRECTIONCHANGE IN DIRECTION
BETWEEN ADJACENTBETWEEN ADJACENT
GROUPS OF RODS.GROUPS OF RODS.
ALTERNATING LIGHTALTERNATING LIGHT
AND DARK BANDS AREAND DARK BANDS ARE
SEEN IN LONGITUDINALSEEN IN LONGITUDINAL
SECTIONS UNDERSECTIONS UNDER
OBLIQUE REFLECTEDOBLIQUE REFLECTED
LIGHT.LIGHT.
USUALLY FOUND INUSUALLY FOUND IN
INNER 2/3 OF ENAMEL ,INNER 2/3 OF ENAMEL ,
STARTING FROM DEJ.STARTING FROM DEJ.
18.
19. • SIGNIFICANCESIGNIFICANCE
FUNCTIONAL ADAPTATIONFUNCTIONAL ADAPTATION
MINIMIZING THE RISK OFMINIMIZING THE RISK OF
CLEAVAGE IN AXIAL DIRECTIONCLEAVAGE IN AXIAL DIRECTION
DUE TO MASTICATORY FORCES.DUE TO MASTICATORY FORCES.
20. GNARLED ENAMELGNARLED ENAMEL
• A COMPLEXA COMPLEX
ARRANGEMENT OFARRANGEMENT OF
RODS WHICHRODS WHICH
INTERTWINEINTERTWINE
IRREGULARLY NEARIRREGULARLY NEAR
THE CUSPAL AREA ORTHE CUSPAL AREA OR
INCISAL REGION.INCISAL REGION.
Gnarled Enamel
22. SIGNIFICANCESIGNIFICANCE
NOT SUBJECTED TONOT SUBJECTED TO
CLEAVAGE AS ISCLEAVAGE AS IS
REGULAR ENAMELREGULAR ENAMEL
DOES NOT YIELDDOES NOT YIELD
READILY TO THE PRESSUREREADILY TO THE PRESSURE
OF BLADED, HANDOF BLADED, HAND
CUTTING INSTRUMENTS INCUTTING INSTRUMENTS IN
TOOTH PREPARATION.TOOTH PREPARATION.
23. DENTINO-ENAMEL JUNCTIONDENTINO-ENAMEL JUNCTION
• ALSO CALLED AS AMELO-DENTINAL JUNCTION.ALSO CALLED AS AMELO-DENTINAL JUNCTION.
•
DEJ is Scalloped in cross section with
convexities directed towards Dentin
24. SIGNIFICANCESIGNIFICANCE
Scalloping is a functional adaptation to increase
the surface area for enamel
Lateral spread of dental caries.
Stress distribution and resist enamel crack
propagation.
25. IN SOMEIN SOME
PATHOLOGICALPATHOLOGICAL
CONDITIONS LIKE -CONDITIONS LIKE -
*DENTINOGENESIS*DENTINOGENESIS
IMPERFECTAIMPERFECTA
* EHLER- DANLOS* EHLER- DANLOS
SYNDROMESYNDROME
DEJ BECOMES FLATDEJ BECOMES FLAT
AND SO ENAMELAND SO ENAMEL
GETS EASILYGETS EASILY
CHIPPED OFF.CHIPPED OFF.
26. ENAMEL TUFTSENAMEL TUFTS
• ARISE AT THE DEJ & REACH INTOARISE AT THE DEJ & REACH INTO
ENAMEL TO ABOUT 1/5 TO 1/3 OFENAMEL TO ABOUT 1/5 TO 1/3 OF
ITS THICKNESSITS THICKNESS
• CONSISTS OF HYPOCALCIFIEDCONSISTS OF HYPOCALCIFIED
RODS & INTERPRISMATICRODS & INTERPRISMATIC
SUBSTANCESUBSTANCE
• CONSISTS OF HIGHEST ENAMELCONSISTS OF HIGHEST ENAMEL
PROTEIN CONCENTRATIONPROTEIN CONCENTRATIONEnamel Tufts
Enamel Spindle
27. • ACCORDING TOACCORDING TO
TENCATES, THESETENCATES, THESE
DEVELOP BECAUSEDEVELOP BECAUSE
OF ABRUPTOF ABRUPT
CHANGES IN THECHANGES IN THE
DIRECTION OFDIRECTION OF
GROUP OF RODSGROUP OF RODS
THAT ARISE FROMTHAT ARISE FROM
DEJ.DEJ.
• BEST VISUALISED INBEST VISUALISED IN
TRANSVERSETRANSVERSE
SECTIONSECTION
28. ENAMEL LAMELLAEENAMEL LAMELLAE
THIN LEAF LIKE HYPO-THIN LEAF LIKE HYPO-
CALCIFIEDCALCIFIED
STRUCTURES.STRUCTURES.
EXTEND FROM OUTEREXTEND FROM OUTER
ENAMEL – DEJ.ENAMEL – DEJ.
FORMED DUE TOFORMED DUE TO
STRESS AND STRAINSSTRESS AND STRAINS
CREATED DURINGCREATED DURING
ENAMEL MATURATION ,ENAMEL MATURATION ,
ALSO CALLED ASALSO CALLED AS
GEOLOGICAL FAULTS.GEOLOGICAL FAULTS.
29. BASED ON CONTENTS OFBASED ON CONTENTS OF
LAMELLAE THEY ARELAMELLAE THEY ARE
DIVIDEDDIVIDED
TYPE A – ONLY ENAMEL--TYPE A – ONLY ENAMEL--
POORLY CALCIFIED RODPOORLY CALCIFIED ROD
SEGMENTSEGMENT
TYPE B –MAY REACHTYPE B –MAY REACH
DENTIN-- DEGENERATEDDENTIN-- DEGENERATED
CELLSCELLS
TYPE C –MAY REACHTYPE C –MAY REACH
DENTIN-- ORGANICDENTIN-- ORGANIC
MATTER FROM SALIVAMATTER FROM SALIVA
30. • BEST VISUALISED INBEST VISUALISED IN TRANSVERSETRANSVERSE
SECTIONSECTION
• LAMELLAE – C.T. - CEMENTUMLAMELLAE – C.T. - CEMENTUM
FORMATION.FORMATION.
- ENAMEL ORGAN- ENAMEL ORGAN
CELLS- HORNIFIED CUTICLECELLS- HORNIFIED CUTICLE
• LAMELLAE ARE SITE OF WEAKNESSLAMELLAE ARE SITE OF WEAKNESS
FOR CARIES INITIATION.FOR CARIES INITIATION.
31. ENAMEL SPINDLESENAMEL SPINDLES
• IS THE THICKENEDIS THE THICKENED
ODONTOBLAST PROCESSODONTOBLAST PROCESS
PASSING ACROSS THE DEJPASSING ACROSS THE DEJ
TO ENAMEL.TO ENAMEL.
• APPEARS DARK INAPPEARS DARK IN
TRANSMITTED LIGHT WHENTRANSMITTED LIGHT WHEN
SEEN IN GROUNDSEEN IN GROUND
SECTIONS.SECTIONS.
Commonly seen in
region of cusp where
most crowding of
odontoblasts occur
32. • BEST SEEN INBEST SEEN IN LONGITUDINALLONGITUDINAL
SECTIONSECTION
SIGNIFICANCESIGNIFICANCE
- SUDDEN SENSITIVITY- SUDDEN SENSITIVITY
EXPERIENCED DURINGEXPERIENCED DURING
CAVITY CUTTING AS THE BURCAVITY CUTTING AS THE BUR
REACHES THE DEJ.REACHES THE DEJ.
33. SURFACE STRUCTURES OF ENAMELSURFACE STRUCTURES OF ENAMEL
• STRUCTURELESS LAYER OF ENAMELSTRUCTURELESS LAYER OF ENAMEL
• CRACKSCRACKS
• ROD ENDSROD ENDS
• PERIKYMATA AND IMBRICATION LINESPERIKYMATA AND IMBRICATION LINES
OF PICKERAL.OF PICKERAL.
34. RODLESS ENAMELRODLESS ENAMEL
• RELATIVELY 30 UM THICK.RELATIVELY 30 UM THICK.
• NO PRISM OUTLINES SEEN,NO PRISM OUTLINES SEEN,
SO PRISMLESS ENAMEL.SO PRISMLESS ENAMEL.
• SEEN IN 70% PERMANENT,SEEN IN 70% PERMANENT,
AND IN ALL DECIDUOUS TEETH.AND IN ALL DECIDUOUS TEETH.
• COMMON IN CERVICALCOMMON IN CERVICAL
AREAS, LEAST AT CUSP TIPSAREAS, LEAST AT CUSP TIPS
35. CRACKSCRACKS ::
• NARROW FISSURE LIKENARROW FISSURE LIKE
STRUCTURES SEEN ONSTRUCTURES SEEN ON
ALMOST ALL SURFACESALMOST ALL SURFACES
• OUTER EDGES OF ENAMELOUTER EDGES OF ENAMEL
LAMELLAELAMELLAE
• DISAPPEARS ONDISAPPEARS ON
DECALCIFICATION.DECALCIFICATION.
• ORIGINATE AT RIGHTORIGINATE AT RIGHT
ANGLES FROM THE DEJANGLES FROM THE DEJ
36. PERIKYMATAPERIKYMATA
WAVE-LIKE TRANSVERSEWAVE-LIKE TRANSVERSE
STRUCTURESSTRUCTURES
PARALLEL TO EACH OTHERPARALLEL TO EACH OTHER
AND TO CEJAND TO CEJ
30 PER MM NEAR CEJ30 PER MM NEAR CEJ
10 PER MM IN10 PER MM IN
CUSPAL/INCISAL AREA.CUSPAL/INCISAL AREA.
ABSENT IN OCCLUSAL PARTABSENT IN OCCLUSAL PART
OF PRIMARY TEETH ANDOF PRIMARY TEETH AND
PRESENT IN POSTNATALPRESENT IN POSTNATAL
CERVICAL AREASCERVICAL AREAS
37. • BELIEVED TO BE THE EXTERNAL MANIFESTATIONS OF STRIAE OF RETZIUSBELIEVED TO BE THE EXTERNAL MANIFESTATIONS OF STRIAE OF RETZIUS
38. ENAMEL ROD ENDSENAMEL ROD ENDS
• CIRCULAR DEPRESSIONSCIRCULAR DEPRESSIONS
• SHALLOWEST – CERVICAL REGIONSSHALLOWEST – CERVICAL REGIONS
DEEPEST – INCISAL OR OCCLUSAL SURFACESDEEPEST – INCISAL OR OCCLUSAL SURFACES
SIGNIFICANCESIGNIFICANCE
CONTRIBUTE TO ADHERENCE OF PLAQUE MATERIALCONTRIBUTE TO ADHERENCE OF PLAQUE MATERIAL
WITH A RESULTANT CARIES ATTACKWITH A RESULTANT CARIES ATTACK
39. DEVELOPMENT OF ENAMELDEVELOPMENT OF ENAMEL
• EPITHELIAL ENAMEL ORGANEPITHELIAL ENAMEL ORGAN
• LIFE CYCLE OF AMELOBLASTSLIFE CYCLE OF AMELOBLASTS
• AMELOGENESISAMELOGENESIS
42. AMELOGENESISAMELOGENESIS
• ENAMEL FORMATION.ENAMEL FORMATION.
• IT IS SLOW DEVELOPMENTALIT IS SLOW DEVELOPMENTAL
PROCESSPROCESS
• CAN TAKE AS LONG AS 5 YRSCAN TAKE AS LONG AS 5 YRS
Ref:Ten Cate:Oral histology development ,structure&function
43. TWO STEP PROCESSTWO STEP PROCESS
•ORGANIC MATRIX FORMATIONORGANIC MATRIX FORMATION
•MINERALIZATIONMINERALIZATION
: PRODUCES PARTIALLY MINERALIZED: PRODUCES PARTIALLY MINERALIZED
ENAMEL(30%)ENAMEL(30%)
: INFLUX OF ADDITIONAL MINERAL: INFLUX OF ADDITIONAL MINERAL
COINCIDENT WITH REMOVAL OF ORGANICCOINCIDENT WITH REMOVAL OF ORGANIC
MATERIAL AND WATERMATERIAL AND WATER
45. STAGES OF AMELOGENESISSTAGES OF AMELOGENESIS
• PRE SECRETORY STAGEPRE SECRETORY STAGE
• SECRETORY STAGESECRETORY STAGE
• MATURATION STAGEMATURATION STAGE
STAGES OF AMELOBLASTSSTAGES OF AMELOBLASTS
• MORPHOGENETIC STAGEMORPHOGENETIC STAGE
• DIFFERENTIATING /ORGANIZINGDIFFERENTIATING /ORGANIZING
• FORMATIVEFORMATIVE
• MATURATIVEMATURATIVE
• PROTECTIVEPROTECTIVE
• DESMOLYTICDESMOLYTIC
Ref:Ten Cate:Oral histology development ,structure&function
46. PRE SECRETORY STAGEPRE SECRETORY STAGE
• DIFFERENTIATING AMELOBLASTSDIFFERENTIATING AMELOBLASTS
ACQUIRE THEIR PHENO TYPEACQUIRE THEIR PHENO TYPE
• CHANGE POLARITYCHANGE POLARITY
• DEVELOP AN EXTENSIVE PROTEINDEVELOP AN EXTENSIVE PROTEIN
SYNTHETIC APPARATUSSYNTHETIC APPARATUS
• PREPARE TO SECRETE THE ORGANICPREPARE TO SECRETE THE ORGANIC
MATRIX OF ENAMELMATRIX OF ENAMEL
Ref:Ten Cate:Oral histology development ,structure&function
47. SECRETORY STAGESECRETORY STAGE
• AMELOBLASTS ELABORATE AND ORGANIZEAMELOBLASTS ELABORATE AND ORGANIZE
ENTIRE ENAMEL THICKNESSENTIRE ENAMEL THICKNESS
•
Ref:Ten Cate:Oral histology development ,structure&function
As initial layer is formed , ameloblasts migrate away
from dentin surface and develop Tomes process.
48. DEVELOPMENT OF TOMES PROCESSDEVELOPMENT OF TOMES PROCESS
• THE SURFACES OF AMELOBLAST FACING THETHE SURFACES OF AMELOBLAST FACING THE
DEVELOPING ENAMEL IS NOT SMOOTH. THERE ISDEVELOPING ENAMEL IS NOT SMOOTH. THERE IS
AN INTERDIGITATION OF CELLS &THE ENAMELAN INTERDIGITATION OF CELLS &THE ENAMEL
RODS THAT THEY PRODUCE.RODS THAT THEY PRODUCE.
• PROJECTION OF AMELOBLAST INTO MATRIX ISPROJECTION OF AMELOBLAST INTO MATRIX IS
CALLED AS TOMES PROCESS CONTAININGCALLED AS TOMES PROCESS CONTAINING
ABUNDANT R.E.R. & MITOCHONDRIA.ABUNDANT R.E.R. & MITOCHONDRIA.
49.
50. -- THE BULK OF EACH ROD ISTHE BULK OF EACH ROD IS
FORMED BY ONEFORMED BY ONE
AMELOBLAST. WHERE AS 3AMELOBLAST. WHERE AS 3
OTHERS CONTRIBUTE TO THEOTHERS CONTRIBUTE TO THE
TAIL OF EACH ROD.TAIL OF EACH ROD.
- EACH ROD IS FORMED BY- EACH ROD IS FORMED BY
4 AMELOBLASTS AND EACH4 AMELOBLASTS AND EACH
AMELOBLASTS CONTRIBUTESAMELOBLASTS CONTRIBUTES
TO 4 DIFFERENT RODS.TO 4 DIFFERENT RODS.
51. DISTAL TERMINAL BARSDISTAL TERMINAL BARS
• DURING FORMATION OF TOMES PROCESSDURING FORMATION OF TOMES PROCESS
TERMINAL BARS APPEAR AT DISTAL ENDTERMINAL BARS APPEAR AT DISTAL END
WHICH SEPARATE TOMES PROCESS FROMWHICH SEPARATE TOMES PROCESS FROM
REST OF CELLSREST OF CELLS
• STRUCTURALLY, LOCALISED CONDENSATIONSTRUCTURALLY, LOCALISED CONDENSATION
OF CYTOPLASMIC SUBSTANCE CLOSELYOF CYTOPLASMIC SUBSTANCE CLOSELY
ASSOCIATED WITH THICKENED CELLASSOCIATED WITH THICKENED CELL
MEMBRANEMEMBRANE
52. MATURATION STAGEMATURATION STAGE
• AMELOBLASTS MODULATE AND TRANSPORTAMELOBLASTS MODULATE AND TRANSPORT
SPECIFIC IONS REQUIRED FOR CONCURRENTSPECIFIC IONS REQUIRED FOR CONCURRENT
ACCRETION OF MINERAL.ACCRETION OF MINERAL.
53. * EACH ROD MATURES FROM DEPTH TO SURFACE AND SEQUENCE OF* EACH ROD MATURES FROM DEPTH TO SURFACE AND SEQUENCE OF
MATURING RODS IS FROM CUSPS OR INCISAL EDGES TOWARDS CERVICALMATURING RODS IS FROM CUSPS OR INCISAL EDGES TOWARDS CERVICAL
LINE.LINE.
54. LIFE CYCLE OF AMELOBLASTS:LIFE CYCLE OF AMELOBLASTS:
DIFFERENTIATION OF AMELOBLASTS IS MOST ADVANCEDDIFFERENTIATION OF AMELOBLASTS IS MOST ADVANCED
IN INCISAL EDGES OR TIPS OF CUSPS AND LEAST ININ INCISAL EDGES OR TIPS OF CUSPS AND LEAST IN
CERVICAL LOOP.CERVICAL LOOP.
LIFE CYCLE IS DIVIDED IN TO 6 STAGESLIFE CYCLE IS DIVIDED IN TO 6 STAGES
1. MORPHOGENIC STAGE1. MORPHOGENIC STAGE
2. ORGANIZING STAGE2. ORGANIZING STAGE
3. FORMATIVE STAGE3. FORMATIVE STAGE
4. MATURATIVE STAGE4. MATURATIVE STAGE
5. PROTECTIVE STAGE5. PROTECTIVE STAGE
6. DESMOLYTIC STAGE.6. DESMOLYTIC STAGE.
55.
56. 1.1. MORPHOGENIC STAGE :MORPHOGENIC STAGE :
• HERE CELLS ARE SHORT AND COLUMNARHERE CELLS ARE SHORT AND COLUMNAR
WITH LARGE OVAL NUCLEI WHICH FILLSWITH LARGE OVAL NUCLEI WHICH FILLS
ENTIRE CELL BODY.ENTIRE CELL BODY.
• MITOCHONDRIA ARE EVENLY DISTRUBUTEDMITOCHONDRIA ARE EVENLY DISTRUBUTED
IN ENTIRE CYTOPLASM.IN ENTIRE CYTOPLASM.
• GOLGI APPARATUS AND CENTRIOLES AREGOLGI APPARATUS AND CENTRIOLES ARE
LOCATED IN THE PROXIMAL ENDS OF THELOCATED IN THE PROXIMAL ENDS OF THE
CELLS.CELLS.
57. 22. ORGANISING STAGE:. ORGANISING STAGE:
THE INNER ENAMEL EPITHELIUM INTERACTSTHE INNER ENAMEL EPITHELIUM INTERACTS
WITH ADJ C/T CELLS, WHICH DIFFERENTIATESWITH ADJ C/T CELLS, WHICH DIFFERENTIATES
INTO ODONTOBLASTS.INTO ODONTOBLASTS.
• AA REVERSAL OF FUNCTIONAL POLARITYREVERSAL OF FUNCTIONAL POLARITY OFOF
CELLS TAKES PLACE AS THERE IS MIGRATIONCELLS TAKES PLACE AS THERE IS MIGRATION
OF GOLGI APPARATUS AND CENTRIOLES -OF GOLGI APPARATUS AND CENTRIOLES -
PROXIMAL ENDS TO DISTAL ENDS, ANDPROXIMAL ENDS TO DISTAL ENDS, AND
MITOCHONDRIA MIGRATES TOWARDS THEMITOCHONDRIA MIGRATES TOWARDS THE
PROXIMAL PART OF THE CELLS.PROXIMAL PART OF THE CELLS.
58. • DURING TERMINAL PHASE OF THEDURING TERMINAL PHASE OF THE
ORGANIZING STAGE,ORGANIZING STAGE, THE FORMATION OFTHE FORMATION OF
DENTINDENTIN BEGINS.BEGINS.
• WHEN DENTIN FORMS IT CUTS OFFWHEN DENTIN FORMS IT CUTS OFF
AMELOBLASTS FROM THEIR ORIGINAL SOURCEAMELOBLASTS FROM THEIR ORIGINAL SOURCE
OF NOURISHMENT, AND FROM HERE THEY AREOF NOURISHMENT, AND FROM HERE THEY ARE
SUPPLIED BY CAPILLARIES THAT SURROUNDSUPPLIED BY CAPILLARIES THAT SURROUND
THEM THEREBYTHEM THEREBY REVERSAL OF NUTRITIONREVERSAL OF NUTRITION..
59. 3.3. FORMATIVE STAGEFORMATIVE STAGE::
-- AFTER THE 1AFTER THE 1STST
LAYER OF DENTIN IS FORMEDLAYER OF DENTIN IS FORMED
AMELOBLASTS ENTER INTO FORMATIVE STAGE.AMELOBLASTS ENTER INTO FORMATIVE STAGE.
- DURING THE FORMATION OF ENAMEL MATRIX THE- DURING THE FORMATION OF ENAMEL MATRIX THE
AMELOBLASTS RETAIN THE SAME LENGTH ANDAMELOBLASTS RETAIN THE SAME LENGTH AND
ARRANGEMENT.ARRANGEMENT.
- INITIATION OF SECRETION OF ENAMEL MATRIX- INITIATION OF SECRETION OF ENAMEL MATRIX..
- AMELOBLASTS DEVELOPS BLUNT CELL PROCESSES ON- AMELOBLASTS DEVELOPS BLUNT CELL PROCESSES ON
THEIR SURFACES CALLED ASTHEIR SURFACES CALLED AS TOMES PROCESSTOMES PROCESS..
60.
61. 44.. MATURATIVE STAGE:MATURATIVE STAGE:
OCCURS AFTER MOST OF THE THICKNESSOCCURS AFTER MOST OF THE THICKNESS
OF ENAMEL MATRIX HAS BEEN FORMED INOF ENAMEL MATRIX HAS BEEN FORMED IN
THE OCCLUSAL OR INCISAL AREAS BUT INTHE OCCLUSAL OR INCISAL AREAS BUT IN
CERVICAL AREAS IT IS STILL IN PROGRESS.CERVICAL AREAS IT IS STILL IN PROGRESS.
- HERE AMELOBLASTS ARE SLIGHTLY- HERE AMELOBLASTS ARE SLIGHTLY
REDUCED IN LENGTH AND ARE CLOSELYREDUCED IN LENGTH AND ARE CLOSELY
ATTACHED TO ENAMEL MATRIX.ATTACHED TO ENAMEL MATRIX.
- AND AMELOBLASTS- AND AMELOBLASTS DISPLAY RUFFLEDDISPLAY RUFFLED
BORDER AND SMOOTH BORDERBORDER AND SMOOTH BORDER
ALTERNATIVELYALTERNATIVELY DISPLAYING THE RESORPTIVEDISPLAYING THE RESORPTIVE
AND SECRETOSY PHASES.AND SECRETOSY PHASES.
62. 55.. PROTECTIVE STAGEPROTECTIVE STAGE::
- WHEN ENAMEL GETS COMPLETELY DEVELOPED AND- WHEN ENAMEL GETS COMPLETELY DEVELOPED AND
HAS FULLY CALCIFIED AMELOBLASTS – S I AND OEE -HAS FULLY CALCIFIED AMELOBLASTS – S I AND OEE -
FORMSFORMS REDUCED ENAMEL EPITHELIUMREDUCED ENAMEL EPITHELIUM WHICHWHICH
PROTECTS THE MATURED ENAMEL.PROTECTS THE MATURED ENAMEL.
6.6. DESMOLYTIC STAGE:DESMOLYTIC STAGE:
- HERE EPITHELIAL CELLS- HERE EPITHELIAL CELLS ELABORATE ENZYMESELABORATE ENZYMES THATTHAT
ARE ABLE TO DESTROY C/T FIBRES BY DESMOLYSIS.ARE ABLE TO DESTROY C/T FIBRES BY DESMOLYSIS.
- PREMATURE DESTRUCTION OF REDUCED ENAMEL- PREMATURE DESTRUCTION OF REDUCED ENAMEL
EPITHELIUM MAY PREVENT ERUPTION OF TEETH.EPITHELIUM MAY PREVENT ERUPTION OF TEETH.
64. AMELOGENESIS IMPERFECTAAMELOGENESIS IMPERFECTA
HEREDITARY DEFECTS OFHEREDITARY DEFECTS OF
ENAMELENAMEL
ECTODERMALECTODERMAL
DISTURBANCE-DEFECT INDISTURBANCE-DEFECT IN
CODING GENE FORCODING GENE FOR
AMELOGENIN.AMELOGENIN.
THERE ARE DIFF TYPES OFTHERE ARE DIFF TYPES OF
AI LIKE;AI LIKE;
1.HYPOPLASTIC1.HYPOPLASTIC
2.HYPOCALCIFIED2.HYPOCALCIFIED
3.HYPOMATURATIVE3.HYPOMATURATIVE
66. HYPOCALCIFIEDHYPOCALCIFIED
• DISTURBANCE INDISTURBANCE IN
EARLYEARLY
MINERALIZATION OFMINERALIZATION OF
ENAMEL.ENAMEL.
• IT APPEARS NORMALIT APPEARS NORMAL
IN THICKNESS.IN THICKNESS.
• SOFT AND CAN BESOFT AND CAN BE
REMOVED EASILYREMOVED EASILY
WITH BLUNTWITH BLUNT
INSTRUMENT.INSTRUMENT.
67. HYPOMATURATIONHYPOMATURATION
INTERRUPTION IN LATE MATURATIONINTERRUPTION IN LATE MATURATION
STAGE.STAGE.
LESS HARD, TRANSLUCENT BUT NOT SOFTLESS HARD, TRANSLUCENT BUT NOT SOFT
NORMAL IN THICKNESSNORMAL IN THICKNESS
CAN BE PIERCED BY LITTLE FIRMCAN BE PIERCED BY LITTLE FIRM
PRESSURE.PRESSURE.
74. LINEAR ENAMEL HYPOPLASIA : THE HORIZONTALLINEAR ENAMEL HYPOPLASIA : THE HORIZONTAL
GROOVES AND PITS ACROSS THE LABIALGROOVES AND PITS ACROSS THE LABIAL
ENAMEL CORRESPONDS TO CESSATION OFENAMEL CORRESPONDS TO CESSATION OF
ENAMEL FORMATION AT ABOUT THE AGE OF 10ENAMEL FORMATION AT ABOUT THE AGE OF 10
MONTHS AS A RESULT OF TEMPORARY METABOLICMONTHS AS A RESULT OF TEMPORARY METABOLIC
DISTURBANCEDISTURBANCE
75. HYPOCALCIFICATION AND INCIPIENT CARIESHYPOCALCIFICATION AND INCIPIENT CARIES
• USUALLY INCIPIENT CARIES IS CONFUSED WITHUSUALLY INCIPIENT CARIES IS CONFUSED WITH
HYPOCALCIFICATION.HYPOCALCIFICATION.
• INCIPIENT CARIES OCCURS WITH INTACTINCIPIENT CARIES OCCURS WITH INTACT
ENAMEL SURFACE ,WITH ENAMEL DESTRUCTIONENAMEL SURFACE ,WITH ENAMEL DESTRUCTION
UNDERNEATH .UNDERNEATH .
• IT LOOKS AS WHITE CHALKY SPOT JUST LIKEIT LOOKS AS WHITE CHALKY SPOT JUST LIKE
LOCALIZED HYPOCALCIFICATION.LOCALIZED HYPOCALCIFICATION.
• IF THE LESION APPEARS IN DRIED TOOTH ANDIF THE LESION APPEARS IN DRIED TOOTH AND
DISAPPEARS IN WET TOOTH- INCIPIENT CARIESDISAPPEARS IN WET TOOTH- INCIPIENT CARIES
• WHEREAS HYPOCALCIFIED SEEN EVEN IN WETWHEREAS HYPOCALCIFIED SEEN EVEN IN WET
TOOTH.TOOTH.
76. ECTOPIC ENAMEL/ ENAMEL PEARLECTOPIC ENAMEL/ ENAMEL PEARL
• PRESENCE OF ENAMEL IN UNUSUAL LOCATIONPRESENCE OF ENAMEL IN UNUSUAL LOCATION
MAINLY ROOTMAINLY ROOT
• MAY CONSIST ENTIRELY OF ENAMEL OR MAYMAY CONSIST ENTIRELY OF ENAMEL OR MAY
CONTAIN UNDERLYING DENTIN & PULP TISSUE.CONTAIN UNDERLYING DENTIN & PULP TISSUE.
• SIGNIFICANCESIGNIFICANCE
PREDISPOSE TO PLAQUE ACCRETION FOLLOWINGPREDISPOSE TO PLAQUE ACCRETION FOLLOWING
GINGIVAL RECESSIONGINGIVAL RECESSION
77. CERVICAL ENAMEL PROJECTIONSCERVICAL ENAMEL PROJECTIONS
LOCATED ON THE BUCCALLOCATED ON THE BUCCAL
SURFACE OF THE ROOTSURFACE OF THE ROOT
OVERLYING THE BIFURCATIONOVERLYING THE BIFURCATION
USUALLY PRESENT ON MOLARSUSUALLY PRESENT ON MOLARS
, LEADING FURCATION, LEADING FURCATION
INVOLVEMENT.INVOLVEMENT.
78. AGE CHANGES IN ENAMELAGE CHANGES IN ENAMEL
• ATTRITIONATTRITION
• DISCOLORATIONDISCOLORATION
• PERMEABLILITYPERMEABLILITY
• MODIFICATION OF SURFACE LAYERMODIFICATION OF SURFACE LAYER
79. ATTRITION:ATTRITION:
• WEAR FACETS INCREASINGLY PRONOUNCED IN OLDERWEAR FACETS INCREASINGLY PRONOUNCED IN OLDER
PEOPLE.PEOPLE.
• EVIDENCED BY LOSS OF VERTICAL DIMENSION OF THEEVIDENCED BY LOSS OF VERTICAL DIMENSION OF THE
CROWN AND BY FLATTENING OF PROXIMAL CONTOUR.CROWN AND BY FLATTENING OF PROXIMAL CONTOUR.
80. DISCOLORATIONDISCOLORATION
• TEETH DARKEN WITH AGETEETH DARKEN WITH AGE
• WHY….?WHY….?
• ADDITION OF ORGANIC MATERIAL OR DEEPENING OFADDITION OF ORGANIC MATERIAL OR DEEPENING OF
DENTINE COLORDENTINE COLOR
81. PERMEABILITYPERMEABILITY
• BECOMES LESS PERMEABLEBECOMES LESS PERMEABLE
• WITH AGE THE PORES DIMINISH AS THE CRYSTALWITH AGE THE PORES DIMINISH AS THE CRYSTAL
ACQUIRE MORE IONS.ACQUIRE MORE IONS.
82. MODIFICATION IN SURFACE LAYERMODIFICATION IN SURFACE LAYER::
• SURFACE OF UNERUPTED AND RECENTLYSURFACE OF UNERUPTED AND RECENTLY
ERUPTED TEETH COVERED WITH PRONOUNCEDERUPTED TEETH COVERED WITH PRONOUNCED
ROD ENDS AND PERIKYMATA.ROD ENDS AND PERIKYMATA.
• GENERALIZED LOSS OF ROD ENDS, SLOWERGENERALIZED LOSS OF ROD ENDS, SLOWER
FLATTENING OF PERIKYMATA LATERFLATTENING OF PERIKYMATA LATER
DISAPPEAR COMPLETELYDISAPPEAR COMPLETELY
84. ENAMEL CARIESENAMEL CARIES
• DESTRUCTION OF THE ENAMEL SURFACE WITHDESTRUCTION OF THE ENAMEL SURFACE WITH
ACID LEAD TO THE DISSOLUTION OF THEACID LEAD TO THE DISSOLUTION OF THE
ENAMEL MATRIX, FOLLOWING IS THE CARIOUSENAMEL MATRIX, FOLLOWING IS THE CARIOUS
ATTACK.ATTACK.
• CARIES PREFERENTIALLY ATTACK CORES OFCARIES PREFERENTIALLY ATTACK CORES OF
RODS AND MORE PERMEABLE STRIAE OFRODS AND MORE PERMEABLE STRIAE OF
RETZIUS , WHICH PROMOTE LATERAL SPREADINGRETZIUS , WHICH PROMOTE LATERAL SPREADING
AND UNDERMINING ADJACENT ENAMEL.AND UNDERMINING ADJACENT ENAMEL.
85. FLUORIDATIONFLUORIDATION
• INCORPORATION OF FL IONS MAKES HYDROXYAPATITEINCORPORATION OF FL IONS MAKES HYDROXYAPATITE
CRYSTALS MORE RESISTANT TO ACID DISSOLUTIONCRYSTALS MORE RESISTANT TO ACID DISSOLUTION
• DECREASING RATE OF DEMINERALIZATION ANDDECREASING RATE OF DEMINERALIZATION AND
INCREASING RATE OF REMINERALIZATION.INCREASING RATE OF REMINERALIZATION.
86. ACID ETCHINGACID ETCHING
• REMOVES PLAQUE , DEBRIS & THIN LAYER OFREMOVES PLAQUE , DEBRIS & THIN LAYER OF
ENAMELENAMEL
• BY DISSOLVING MINERALS IN ENAMEL,BY DISSOLVING MINERALS IN ENAMEL,
ETCHANTS REMOVE THE OUTER 10 MICROMETERSETCHANTS REMOVE THE OUTER 10 MICROMETERS
ON THE ENAMEL SURFACE AND MAKES A POROUSON THE ENAMEL SURFACE AND MAKES A POROUS
LAYER 5–50 MICROMETERS DEEPLAYER 5–50 MICROMETERS DEEP
• IT INCREASES POROSITY THROUGH DISSOLUTIONIT INCREASES POROSITY THROUGH DISSOLUTION
OF CRYSTALSOF CRYSTALS
87. TYPES OF ETCHING PATTERN-TYPES OF ETCHING PATTERN-SILVERSTONE,1975SILVERSTONE,1975
• TYPE-1 PREFERENTIALTYPE-1 PREFERENTIAL
REMOVAL OF RODREMOVAL OF ROD
CORES.CORES.
• TYPE-2 PERIPHERYTYPE-2 PERIPHERY
OF RODS REMOVEDOF RODS REMOVED
• TYPE-3 IRREGULAR,TYPE-3 IRREGULAR,
INDISCRIMINATEINDISCRIMINATE
REMOVAL.REMOVAL.
88. BLEACHINGBLEACHING
• LIGHTENING OF COLOR OF A TOOTH THROUGHLIGHTENING OF COLOR OF A TOOTH THROUGH
THE APPLICATION OF A CHEMICAL AGENT TOTHE APPLICATION OF A CHEMICAL AGENT TO
OXIDIZE THE ORGANIC PIGMENTATION IN THEOXIDIZE THE ORGANIC PIGMENTATION IN THE
TOOTH.TOOTH.
• TRANSITORY DECREASE IN THE POTENTIAL BONDTRANSITORY DECREASE IN THE POTENTIAL BOND
STRENGTH OF COMPOSITE WHEN APPLIED TOSTRENGTH OF COMPOSITE WHEN APPLIED TO
BLEACHED SURFACEBLEACHED SURFACE
• NO LOSS IF COMPOSITE IS APPLIED 1 WEEK AFTERNO LOSS IF COMPOSITE IS APPLIED 1 WEEK AFTER
THE CESSATION OF THE THERAPYTHE CESSATION OF THE THERAPY