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
Difference between primary and permanent teethprincesoni3954
The presentation features the basic difference between primary and permanent dentition. The differences are tabulated under the headings of crown, roor and pulp.
A detailed look at the differences between the human primary and permanent dentition. Hope you find this informative. for further queries, please contact at dr.mathewthomasm@gmail.com.
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
Difference between primary and permanent teethprincesoni3954
The presentation features the basic difference between primary and permanent dentition. The differences are tabulated under the headings of crown, roor and pulp.
A detailed look at the differences between the human primary and permanent dentition. Hope you find this informative. for further queries, please contact at dr.mathewthomasm@gmail.com.
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
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.
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.
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 Brief Description about the development of teeth. Understanding the process of tooth development is of particular importance for the dentist; as developmental disturbances may occur at any stage of this process resulting in different types of tooth anomalies.
Tooth development can be classified either based on morphology or histology
Morphological stages:
Bud stage
Cap stage
Bell stage:
* Early
* Advanced
Physiological stages:
Initiation
Proliferation
Histodifferentiation
Morphodifferentiation
Apposition
BE UPDATE TO IT,, AS IT IS 3 years back from 2017
Kindly mail me if you feel, needy of this presentation
you can find my mail id @ slide share,,, if not mail me @
sukesh3567@gmail.com.
Good luck
The initiation of tooth development begins at 37 days of development
with formation of a continuous horseshoe-band of thickened epithelium
in the location of upper and lower jaws – Primary Epithelial Band
Dental lamina appears as a thickening
of the oral epithelium adjacent to
condensation of ectomesenchyme
20 areas of enlargement or knobs
appear, which will form tooth buds
for the 20 primary teeth
Not all will appear at the same time.
The first to develop are those of the
anterior mandible region
At this early stage the tooth buds
have already determined their crown morphology
Successional lamina: lamina from
which permanent teeth develop
The dental lamina begins to function
at 6th prenatal week and continues to
15th year of birth (3rd molar)
Tooth development is a continuous process, however can be
divided into 3 stages:
1. Bud Stage
2. Cap Stage
3. Bell Stage
4. Hertwigs epithelial root sheath and root formation
The bud stage is represented by the first epithelial incursion into the ectomesenchyme of the jaw.
The epithelial cells show little if any change in shape or function.
The supporting ectomesenchymal cells are packed closely beneath and around the epithelial bud. As the epithelial bud continues to proliferate into the ectomesenchyme, cellular density increases immediately adjacent to the epithelial outgrowth.
This process is classically referred to as a condensation of the ectomesenchyme.
The epithelium of the dental lamina separated from the underlying ectomesenchyme by basement membrane.
Bud stage is characterized by rounded, localized growth of
epithelium surrounded by proliferating mesenchymal cells,which are packed closely beneath and around the epithelial buds
The transition from bud to cap marks the onset of morphologic differences between tooth germs that give rise to different types of teeth.
Differential cellular division in the epithelial bud initiates a change in shape so that now the epithelial outgrowth assumes a more complex outline with a flattened internal portion along which the mesenchymal condensation densifies.
As the tooth bud grows larger, it drags along with it part of the dental lamina; thus from that point on, the developing tooth is tethered to the dental lamina by an extension called the lateral lamina.
At this early stage of tooth development, identifying the formative elements of the tooth and its supporting tissues is already possible.
The epithelial outgrowth, which superficially resembles a cap sitting on a ball of condensed ectomesenchyme , is still referred to widely as the dental organ but actually should be called the enamel organ, because it eventually will form the enamel of the tooth. Henceforth, the term enamel organ is used.
Condensation of the ectomesenchyme immediately subjacent to the tooth bud caused by lack of extracellular matrix secretion by the cells thus preventing separation.
Similar to Growth and development of tooth/ oral surgery courses (20)
Opportunity for Dentists (BDS/MDS )to relocate to United kingdom -Register as a DENTAL HYGIENIST/ DENTAL THERAPIST without Board exams and after approval you can register in GDC as a DH/DT and start working as a DH/DT Immediately and get paid.
You can complete the whole process in 3-4 months.Salary range for DH/DT is around 2500-3500 Pounds per month.
Eligibility / requirements-
1. An International English Language Testing System (IELTS) certificate
at the appropriate level.(Within 2 yrs of application date )
2: A recent primary dental qualification that has been taught and examined in English..(Within 2 yrs of application date )
3: A recent pass in a language test for registration with a regulatory authority in a country where the first language is English.
If you are interested Please contact us for more details.
1ST, 2ND AND 3RD ORDER BENDS IN STANDARD EDGEWISE APPLIANCE SYSTEM /Fixed ort...Indian 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.
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.
I –Aligners are made with FDA approved transparent thermoplastic materials using 3D scanning, 3D Printing and finally Trays with Pressure vacuum formers.
Dear Doctor,
Indian Dental Academy Now offers comprehensive online Orthodontics course.
Course includes:
1.whiteboard lecture presentations
2.Case Discussions
3.with hundreds of pictures.
4.Demo on Models
5.Demo on Patients
6. subtitles in your own language
12 months unlimited access and support @350 USD only.
For Demo please visit :www.idalectures.com/preview/
For more details visit: www.idalectures.com
Please contact us for any clarifications:
idalectures@gmail.com
indiandentalacademy@gmail.com
Thanks & Regards
Indian Dental Academy
--
Indian Dental Academy
Leader in continuing dental education
www.indiandentalacademy.com
skype:indiandentalacademy
+919248678078
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
Cytotoxicity of silicone materials used in maxillofacial prosthesis / dental ...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.for more details please visit
www.indiandentalacademy.com
Diagnosis and treatment planning in completely endntulous arches/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
Properties of Denture base materials /rotary endodontic 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
Use of modified tooth forms in complete denture occlusion / dental implant...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.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
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
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
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
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
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
2. CONTENTS
• Introduction
• Definition of Growth & Development
• Formation of Dental lamina
• Developmental stages of tooth
• Development of Enamel, dentin, cementum, pulp,
periodontal ligament.
• Factors affecting growth & development
• Developmental anomalies and prosthetic
considerations
• Summery & Conclusion
• References. www.indiandentalacademy.com
3. INTRODUCTION
It is essential to study the growth &development of tooth, to
diagnose & treat the developmental anomalies of teeth
successfully.
According to Todd.
• Growth refers to an increase in no and size
• Development refers to an increase in complexity and maturity.
• Growth may be defined as an increase in weight and spatial
dimensions that an organism or organ goes through. The
organism or organ gets heavier and takes up space. For growth
to occur, three things must happen: (1) increase in number of
cells, (2) increase in size of cells, and (3) increase in the product
of the cells.
• Development is an organism or organ going toward maturity.www.indiandentalacademy.com
4. FORMATION OF DENTAL LAMINA
• At about 21st
day of embryonic life the embryo folds along two planes
rostocaudal and lateral.
• The head fold is critical for the formation of primitive stomatodeum or oral
cavity, lined by stratified squamous epithelium, oral ectoderm.
Neural Crest Cells: This is ectomesenchymal tissue, termed neural crest from
its site of origin, arises from crest of neural fold, where neutralizing and
epidermalizing influences the interact.
- Pleuripotential cells with great migratory propensities.
Primary Epithelial Band: Roughly horse shoe shaped epithelial bands
corresponding in position to future upper and lower jaws.
Formed as a result of change in orientation of mitotic spindle and cleavage plain
of dividing cells and gives rise to dental lamina and vestibular lamina.
www.indiandentalacademy.com
5. • The band of epithelium that invades the underlying
ectomysenchyme along each of horse shoe shaped future dental
arches called Dental lamina at about 6th
week of embryonic life.
Importance:
• Primordium for the ectodermal portion of deciduous teeth.
• Successional tooth buds .
• Buds for permanent molars from distal extension of dental
lamina.
• Dental lamina degenerates at about 5th
year of life.
• Remnants persist as epithelial pearls / islands.
Vestibular Lamina / Lip Furrowband:
• Epithelial thickening labial and buccal to dental lamina in each
dental arches.
• Forms oral vestibule.www.indiandentalacademy.com
7. STAGES IN TOOTH DEVELOPMENT
The stages are named after the shape of the epithelial part of
the tooth germ.
1) BUD STAGE:
a) The ectodermal cells along the dental lamina multiply
rapidly in to round or ovoid swellings at different points
corresponding to the position of future deciduous teeth.
b) These form the primordium for the enamel organs of the
tooth bud.
c) It consist of
i. low columnar cells at periphery and polygonal cells at the
centre.
ii. Dental papilla.
iii. Dental sac.
www.indiandentalacademy.com
9. 2) CAP STAGE:
This stage is characterized by the shallow invagination on the
deep surface of the bud as a result of continued proliferation.
• In this stage cells of enamel organ can be histologically
differentiated as follows:
• Outer enamel epithelium (OEE). – peripheral cuboidal cells.
• Inner enamel epithelium (IEE) – columnar cells.
• Stellate reticulum
–polygonal cells located in the center.
–provides cushion like effect, thus supports
and protects delicate enamel forming cells
• Enamel knot – the densely packed cells in the center enamel
organ.
• Enamel cord – a vertical extension of the enamel knot between
inner and outer enamel epithelium.
• Dental papilla – the ectomesenchymal cells proliferate and
condense under the influence of proliferating epithelium.
• Dental sac – the dense fibrous layer.
www.indiandentalacademy.com
11. 3) BELL STAGE:
• The epithelial invagination deepens and the margins continue to
grow, thus the enamel organ assumes bell shape.
• Stage consist of
• IEE – Single layer of tall columnar cells called ameloblasts.
• Stratum Intermedium – squamous cells present in between
IEE and stellate reticulum. Shows high degree of mitotic
activity.
• Stellate reticulum – star shaped cells. Collapses before enamel
formation.
• OEE – flattens to low cuboidal form.
– surface laid in folds at the end of bell
stage prior to enamel formation begins.
• Dental lamina
• Dental papilla – odonto blasts differentiation.
• membrane performativa.
• Dental sac – circular arrangement of fibers and resembles
capsular structure.
www.indiandentalacademy.com
13. 4) ADVANCED BELL STAGE :
• Future dentino enamel junction.
• Cervical portion of enamel organ forms the hertwig’s
epithelial root sheath.
Hertwig’s Epithelial Root Sheath and Root formation:
• Root development starts after enamel and dentin formation
reaches future cemento enamel junction.
• Enamel organ forms hertwig’s epithelial root sheath
consisting of inner and outer enamel epithelium. It modes
the shape of roots and initiates radicular dentin formation.
• The sheath looses its continuity after radicular dentin
formation.
www.indiandentalacademy.com
14. • Cementoblast form cementum over dentin.
• Epithelial diaphragm – the inner and outer enamel
epithelium bend at the future CEJ into horizontal plane
narrowing wide cervical opening. The cells proliferate
along with adjacent connective tissue cells of pulp.
• Apical foramen opening is narrowed by the deposition of
dentin and cementum at the apex of root.
• In multi rooted teeth the differential growth of epithelial
diaphragm causes division of root trunk in to two or three
roots.
• The long tongue like extensions of the horizontal
diaphragm develops two in mandible, three maxilla.
Before this the free ends grow towards each other and fuse.
• The cervical opening of coronal enamel organ is divided in
to two or three openings and dentin formation starts on the
periphery of each opening.www.indiandentalacademy.com
16. Break up of dental lamina and crown pattern determination during Bell
stage: two events
• The dental lamina joining tooth germ to oral epithelium breaks up in to
discrete islands.
• IEE folds because of differential mitotic activity and thus the shape of future
crown pattern can be recognized.
• The point of maturation of cells determines site of future cusp developments.
• The determination of shape of the tooth is emphasized by following:
– One proposes that factors responsible are present within ectomesenchyma
with distinct graded fields for each tooth family.
– Clone model; proposes that, each tooth class derived from
ectomesenchymal cells programmed by epithelium to produce teeth of
given pattern.
www.indiandentalacademy.com
17. AMELOGENESIS
Two step process:
• 30% partially mineralized dentin formation.
• involves removal of organic matter and water with significant influx of
more than 96% mineral content.
• The enamel organ consist of 4 layers:
• Outer enamel epithelium – early stages single layer cuboidal cells.
– prior to enamel formation becomes irregular shaped with folds.
– during amelogenesis cells develop specialization for active transport of
materials.
• Stellate reticulum – star shaped cells.
• Functions :
• Buffering action against physical forces that might distort the developing
DEJ conformation.
• Permits limited flow of nutrients.
www.indiandentalacademy.com
18. • Stratum intermedium – flat to cuboidal shape in one or
three layer, decrease in thickness after dentin formation.
• Function:
• Role in production of enamel by controlling fluid diffusion
in to and out of ameloblasts.
• Inner enamel epithelium.
• Cervical loop
www.indiandentalacademy.com
19. LIFE CYCLY OF AMELOBLASTS
1) MARPHOGENIC STAGE
• Low columnar cells with large oval centrally located
nuclei, golgiapparatus, centrioles at proximal end of cell.
2) ORGANIZING STAGE
• Cells of inner enamel epithelium become toll columnar,
golgi apparatus, centrioles move to distal end nucleus
proximally with mitochondria .
• Junctional complexes determine what may or may not
enter into or out of ameloblasts.
• Nutritional supply to IEE after pre-dentin formation.
3) FORMATIVE STAGE
• Organogenesis & histo-differentiation .
www.indiandentalacademy.com
20. 4) MATURATION STAGE:
• Occurs after most of enamel matrix has been
formed
• starts at occlusal & incisal edges.
• Ameloblasts short columnar enamel matrix.
• Stratum intermedium ---spindal shaped
• Absorptive function indicated by microvilli &
cytoplasmic vacuoles.
www.indiandentalacademy.com
21. 5) PROTECTIVE STAGE.
• Stratified epithelial cells covering the formed enamel is
called reduced enamel epithelium.
• Protects the enamel by separating it from the connective
tissues of dental sac
6) DESMOLYTIC STAGE
The reduced enamel epithelium proliferate & induces
atrophy of connective tissues separating it from oral
epithelium so that fusion of two epithelia occurs,
elaborates enzymes, causes connective tissue desmolysis.
www.indiandentalacademy.com
22. FORMATION OF ENAMEL MATRIX
• The ameloblasts secrete the enamel after a layer of predentin
formation .
• Aprismatic layer of enamel forms dentino enamel
membrane.
THE DEVELOPMENT OF TOME’S PROCESS
• The projection of ameloblasts into the enamel matrix are
termed as tome’s process .
• Cells contains typical secretory granules as well as rough
endoplasmic reticulum &mitocondria.
• Distal terminal bars.
• the ameloblasts show extensive golgi complex with rough
endoplasmic reticulum occupying supra nuclear
compartments.
www.indiandentalacademy.com
23. • Identified by the presence of abundant membrane in
foldings. The secretions of these sites along with adjacent
ameloblasts results in formation of enamel partitions that
delimit a pit with tome’s process thus inter rod enamel is
found.
• Second site one face of distal portion of tome’s process
fills pits with matrix.so rod enamel formed.
• The narrow space between rod an inter-rod by squeezing
out tome’s process, is filled with organic material called as
rod-sheath.
• In the outer third of enamel rods have slightly different
profile an rectilinear trajectory because of distal portion
orientation to cell body.
• Final few increments are aprismatic enamel.
www.indiandentalacademy.com
24. 3) MATURATION STAGE
Transitional phase
• Ameloblasts undergo morphologic changes for
maturing enamel; involves reduction in height
,decrease in volume & organelle content.
• Absorptive cell morphology ;villous surface
&cells with mitochondria.
www.indiandentalacademy.com
25. Maturation Proper
• Ameloblasts are involved in removal of organic matrix
&water content of enamel matrix.
• Ruffled ended ameloblasts show proximal leaky junction
&tight distal. Pumping action of calcium into enamel
matrix is produced by membrane associated with calcium
adenosinetriphosphatase.
• Smoothened cells show distal junctions that is leaky and
proximal tight. It leaks out small proteins and other
molecules.
• Removal of organic matrix is attributed to degrading
enzymes, polypeptide fragments leave enamel through
leaky distal junction of smoothened cell.www.indiandentalacademy.com
26. MINERALIZATION AND MATURAION OF ENAMEL MATRIX.
Two stages:
• First stage immediate partial mineralization occurs
in matrix segment and interprismatic substance in
the form of crystalline apatite. Comprises about
25% to 30% of total mineral content.
• Second stage / maturation – characterized by
gradual completion of mineralization.
– It is a integration of two processes
– Ultra structural level shows
• Maturation is characterized by growth of crystals
• The original ribbon shaped crystals increase in
thickness more rapidly than in width.
• Organic matrix becomes thin and provides room for
growing crystals.www.indiandentalacademy.com
28. DENTINOGENESIS
Formation of odontoblasts
• The odontoblasts are tall columnar cells with increased
protein synthesizing organelles and centrally located
nuclei.
• Cells are 40 µm in length and 7 µm in width.
• Proline appears in rough endoplasmic reticulum and golgi
apparatus and migrates into cell processes in dense
granules, which are emptied into extra cellular collagenous
matrix of predentin.
www.indiandentalacademy.com
29. FORMATION OF MANTLE DENTIN
• The odontoblasts deposit first dentin collagen in to ground
substance.
• The type III collagen fibers with fibronectin called
VonKorff’s fibers.
• Odontoblast continue to increase in size and produce type I
collagen fibrils orient parallel to future DEJ.
• Dentinal tubules enclose several cell processes of
odontoblasts.
• Predentin is formed along pulpal borders remains for one
day before calcification and next layer of dentin formation.
• Initially 4 µm of dentin is formed, slows to 1 µm per day
after teeth erupts and moves into occlusion and decrease
further after root development.
• Reparative dentin may form at a 4 µm per day rate for
several days after tooth is restored.
www.indiandentalacademy.com
30. MINERALIZATION
• The earliest crystal deposition is in the form of very fine
plates of hydroxy apatite on the surface of collagen and
ground substance.
• The crystals are arranged with their long axis paralleling
the fibril axis and in rows conforming into 64nm striation
pattern.
• Within globular islands of mineralization crystal
deposition appears to take place radially from common
centers in a so called spherulite form.
• Two patterns of mineralization ie globular & linear
calcification
www.indiandentalacademy.com
31. • Mineralization is achieved by continuos deposition of
mineral .initialy in the matrix vesicle &then at
mineralization front.
• Calcospherite mineralization is occasionally seen along
pulp al predentin .
• The peritubular dentin is highly mineralized.
• The ultimate crystal size 3nm in thickness &100nm in
length.
• Root Dentin:less degree of mineralization ,phosphoryn
content is less.
• Secondary &Tertiary Dentin
• Neonatal Line www.indiandentalacademy.com
32. Bell stage of tooth development both
dentinogenesis and amelogenesis
Dentinogenesis
www.indiandentalacademy.com
33. CEMENTO GENESIS:
• Cementoblast formation
• Cementoblast cell structure shows secretary
organelles.
• The uncalcified matrix is called cementoid .
• Cementum formation occurs in rhythmic
process.
www.indiandentalacademy.com
34. Mineralization of Cementum:
• Mineralization occurs after some cementum
matrix is laid down.
• The calcium&phosphate ions from tissue fluid are
deposited & arranged as unit of hydroxy apatite .
• Cellular –cementum present in apical half of root.
• A cellular cementum in coronal half of root.
• The cementoid layer observed over mineralizing
cementum..
• Sharpey’s fibers.www.indiandentalacademy.com
35. • Pulp tissue originates from dental papilla which
determines whether the tooth is incisor or molar.
• At about 8th
week of embryonic life dental pulp
development begins at future incisor location.later
on more posterior tooth.
• Young dental papilla shows organized vascular
network by the time dentin formation begins.
• Differentiation of fibroblasts & odonto blasts.
• Large myelinated nerves following blood vessels
enter into pulp&pulp organization begins.
DEVELOPMENT OF PULP
www.indiandentalacademy.com
37. DEVELOPMENT OF PERIODONTAL LIGAMENT
• Develops from cells of dental follicle
• Cells of dental follicle differentiate into cementoblasts,
fibroblasts, osteoblasts.
• The formation of periodontal ligament occurs after
completion of root dentin & cementum.
• The fibers of periodontal ligament are embedded in
cementum of tooth&alveolar bone&orient in characteristic
fashion after tooth eruption.
www.indiandentalacademy.com
38. Factors affecting growth&development
broadly classified as
1. Genetic:
i. Inherited
ii. Mutagenic
2. Environmental Factors:
a. Infections :
i. Systemic:
- Rudella
- Influenza
o ii. Local: periapical infection
affecting deciduous tooth
www.indiandentalacademy.com
39. b. Exanthematous diseases: measles ,chickenpox ,scarlet fever.
c. Physical injuries: trauma , radiation,extra temperature.
d. Hormonal disturbances: parathyroid ,thyroid ,growth
hormone, pituitary hormone .
e. Nutritional deficiency : vitamin A,Vit B complex Vit C,Vit
D, proteins, aminoacides.
f. Hypocalcemia
g. Birth injury-premature birth ,traumatic birth,RH hemolytic
disease.
h. Congenital syphilis:
i. Ingestion of chemicals
j. Idiopathic
k. Miscellaneous drugs & chemicals:teratogenic
l. Maternal disease & defects
m. Embryonic defectswww.indiandentalacademy.com
40. DEVELOPMENTAL DISTURBANCES OF TEETH & PROSTHODONTIC
CONSIDERATIONS
1) Amelogenesis imperfecta / hereditary enamel dysplasia
/heriditary brown enamel/heriditary brown opalescent teeth.
Classification; by witkop sauk
Hypoplastictype-1.Pitted autosomal dominant
2.Local autosomal dominant
3.Smooth autosomal dominant
4.Rough autosomal dominant
5.Rough autosomal recessive
6.Smooth x-linked dominant
Hypocalcified-- a) Autosomal dominant
b) Autosomal recessive
Hypomaturation-a) Autosomal dominant with tarodontism
b) X-linked recessive
c) Pigmented autosomal recessive
d) Snow capped teeth
www.indiandentalacademy.com
44. Dentinogenesis imperfecta/Hereditary opalescent dentin
Shields & co-workers classified as –
a.Type I- occurs with osteogenesis imperfecta
– Autosomal dominant
– Desiduous teeth severly affected
– Discoloration of teeth
– Short blunt roots
b.Type II-not associated with OI
- Autosomal dominant
- Radio graphs show obliterated pulp chamber
c.Type III- Brandy wine type
Multiple pulp exposures in deciduous teeth
• Shell teeth
• Prosthodontic considerationswww.indiandentalacademy.com
45. Dentin dysplasia(root less teeth):atypical dentin,abnormal
pulp
a. Type I-radicular
• Delayed eruption,extreme mobility short roots
• Prosthodontic considerations
b.Type II-coronal
In deciduous teeth obliterated pulp chamber. In
permanent thistle tube shaped.
Regional odonto dysplasiaGhost teeth
clinically delay or failure to erupt irregular
appearance of teeth.
Prosthodontic consideration fabrication of
restorations
www.indiandentalacademy.com
46. Developmental disturbances in size
1) Microdontia
• True generalized-pituitary dwarfism
• Relatively generalized
• Single tooth
2) Macro dontia
Developmental disturbances in shape of the
tooth
1) Gemination
An attempt at division of single tooth germ by
invagination resulting in incomplete formation
of two teeth
2)Fusion
Union of two developing tooth germwww.indiandentalacademy.com
48. 1) Number of Teeth
Anodontia
• Congenital absence
– Total Anodontia-
hereditaryectodermal dysplasia
– Partial Anodontia
2) Supernumerary teeth
• Gardener’s syndrome
www.indiandentalacademy.com
49. Prosthodontic Considerations
• During crown preparation patient may complain about sensitivity
because of exposed dentin and there may be requirement of
provisional restoration before permanent prosthesis is fabricated
and cemented to avoid discomfort to the patient because of
exposed dentinal sensitivity.
• Cementum resorption can occur because of trauma or excessive
occlusal forces. In severe cases resorption may continue in dentin.
Followed by repair by forming an cementum I.e. anatomical or
functional.
• Under excessive occlusal stresses there will be hypercementosis.
• The periodontal ligament tissue of a tooth which was out of
function for a long time, will take time to adapt to new functional
demands, this applies to bridge abutments, teeth opposing bridges
or dentures.
www.indiandentalacademy.com
50. Summary & Conclusion:
• Tooth development occurs in following
stage Bud stage, cap stage, Bell stage
www.indiandentalacademy.com
51. References
• Orban’s oral histology &embryology
• Ten cate’s oral histology
• essentials of oral pathology&oral medicine by
R.A.Cowson.E.N.Odell 7th
edition
• Color atlas of oral pathology 4th
edition by Hamiltan
B.G.Robbinson;Arthur,S.Miller.
• Color atlas of clinical oral pathology by
Blad.W.Neville,Douglas D.damm,Deank-white 2nd
edition
• Text book of oral pathology by Shafer 4th
edition.
• Permar’s Oral Embryology and Microscopic Anatomy –
eighth edition, Rudy C. Melfi.
www.indiandentalacademy.com