The document provides an overview of the periodontium, which includes the gingiva, periodontal ligament, cementum, and alveolar bone. It describes the microscopic and macroscopic structure of each component in detail. The gingiva is divided into marginal, attached, and interdental regions. It has an epithelial layer and connective tissue layer. The periodontal ligament connects the cementum to the alveolar bone and contains fibers and cellular elements. Cementum covers the root surface and comes in acellular and cellular varieties. The alveolar bone provides support and structure for the teeth. Each component works together to attach and support the teeth.
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Prosthesis is one of the most important component of an implant. There are various prosthetic factors that must be considered for a successful implant. Few of them include prosthesis type and material, the connection between abutment and prosthesis, occlusal factors, etc.
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offering a wide range of dental certified courses in different formats.for more details please visit
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Implants in esthetic zone. / implant dentistry course/ implant dentistry courseIndian 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.
Endodontic treatment is largely performed on teeth significantly affected by caries, multiple repeat restorations and/or fracture. Already structurally weakened, such teeth are often further weakened by the endodontic procedures designed to provide optimal access and by the restorative procedures necessary to rebuild the tooth.
It is therefore accepted that endodontically treated teeth are weaker and tend to have a lower lifetime prognosis. They require special considerations for the final restoration which involve ensuring both adequate retention for the final restoration and maximum resistance to tooth fracture.
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.
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.
Prosthesis is one of the most important component of an implant. There are various prosthetic factors that must be considered for a successful implant. Few of them include prosthesis type and material, the connection between abutment and prosthesis, occlusal factors, etc.
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
Implants in esthetic zone. / implant dentistry course/ implant dentistry courseIndian 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.
Endodontic treatment is largely performed on teeth significantly affected by caries, multiple repeat restorations and/or fracture. Already structurally weakened, such teeth are often further weakened by the endodontic procedures designed to provide optimal access and by the restorative procedures necessary to rebuild the tooth.
It is therefore accepted that endodontically treated teeth are weaker and tend to have a lower lifetime prognosis. They require special considerations for the final restoration which involve ensuring both adequate retention for the final restoration and maximum resistance to tooth fracture.
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.
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.
• Introduction
• Definitions
• Macroscopic Features
• Microscopic Features
• Blood supply
• Nerve supply
• Lymphatic drainage
• Role of epithelium in defence mechanism
• Oxygen consumption of gingiva
• Correlation of Macroscopic with microscopic features
• Conclusion
macroscopic/ clinical features of gingiva
With video clips
Short video descriptions
Lecture for 3rd BDS students
Periodontology
Periodontics aspect
Clinical features of the gingiva
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.
Macroscopic features of Gingiva.
This presentation will help and let u know about the Development and Macroscopic features of gingiva in detail. Thank you.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
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Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
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spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
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. Our search finds no candidates
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impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
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models for evolution of the dark matter halo mass function.
The increased availability of biomedical data, particularly in the public domain, offers the opportunity to better understand human health and to develop effective therapeutics for a wide range of unmet medical needs. However, data scientists remain stymied by the fact that data remain hard to find and to productively reuse because data and their metadata i) are wholly inaccessible, ii) are in non-standard or incompatible representations, iii) do not conform to community standards, and iv) have unclear or highly restricted terms and conditions that preclude legitimate reuse. These limitations require a rethink on data can be made machine and AI-ready - the key motivation behind the FAIR Guiding Principles. Concurrently, while recent efforts have explored the use of deep learning to fuse disparate data into predictive models for a wide range of biomedical applications, these models often fail even when the correct answer is already known, and fail to explain individual predictions in terms that data scientists can appreciate. These limitations suggest that new methods to produce practical artificial intelligence are still needed.
In this talk, I will discuss our work in (1) building an integrative knowledge infrastructure to prepare FAIR and "AI-ready" data and services along with (2) neurosymbolic AI methods to improve the quality of predictions and to generate plausible explanations. Attention is given to standards, platforms, and methods to wrangle knowledge into simple, but effective semantic and latent representations, and to make these available into standards-compliant and discoverable interfaces that can be used in model building, validation, and explanation. Our work, and those of others in the field, creates a baseline for building trustworthy and easy to deploy AI models in biomedicine.
Bio
Dr. Michel Dumontier is the Distinguished Professor of Data Science at Maastricht University, founder and executive director of the Institute of Data Science, and co-founder of the FAIR (Findable, Accessible, Interoperable and Reusable) data principles. His research explores socio-technological approaches for responsible discovery science, which includes collaborative multi-modal knowledge graphs, privacy-preserving distributed data mining, and AI methods for drug discovery and personalized medicine. His work is supported through the Dutch National Research Agenda, the Netherlands Organisation for Scientific Research, Horizon Europe, the European Open Science Cloud, the US National Institutes of Health, and a Marie-Curie Innovative Training Network. He is the editor-in-chief for the journal Data Science and is internationally recognized for his contributions in bioinformatics, biomedical informatics, and semantic technologies including ontologies and linked data.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
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holes and slow-speed, highly variable, streams whose source regions are
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solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
8. VASCULARIZATION OF PERIODONTIUM.
AGE CHANGES IN PERIODONTIUM.
PROSTHODONTIC CONSIDERATIONS.
CONCLUSION.
REFERENCES.
8
9. INTRODUCTION -
1} In Periodontium , ‘ Peri’ means ‘ around’ and ‘ odont’
means ‘ tooth’.
2} It is a multilayered complex of tissues that surrounds ,
attaches and supports each tooth to the underlying alveolar
bone.
3} It is also called as an ‘ Attachment Apparatus’ .
9
10. 4} It consists of 4 principal components :-
A) GINGIVA.
B) PERIODONTAL LIGAMENT.
C) CEMENTUM.
D) ALVEOLAR BONE.
10
13. GINGIVA.
Carranza : It covers the alveolar bone and tooth root to
a level just coronal to the cementoenamel junction.
Lindhe : The gingiva is that part of the masticatory
mucosa which covers the alveolar process and surrounds
the cervical portion of the teeth.
13
15. MACROSCOPIC FEATURES :
A) MARGINAL GINGIVA ~
The marginal or unattached gingiva is the terminal edge
or border of the gingiva that surrounds the teeth in
collar-like fashion .
The free gingiva is coral pink, and it is demarcated from
the adjacent attached gingiva by a shallow linear
depression called the free gingival groove(FGG).
15
17. The marginal gingiva is usually about 1 mm wide, and it
forms the soft-tissue wall of the gingival sulcus.
Can be separated by a periodontal probe.
The most apical point is called the ‘Gingival Zenith’.
Apicocoronal = 0.06mm.
Mesiodistal= 0.96mm.
17
18. B) GINGIVAL SULCUS ~
The gingival sulcus is a shallow crevice. (Orbans and
Mueller).
It is ‘v’ shaped and barely permits the entrance of a
periodontal probe.
It is bounded by tooth on one side and sulcular
epithelium on other side.
The sulcus is coronal to the attachment of junctional
epithelium.
The coronal extent of gingival sulcus is gingival margin .
18
19. Ideal conditions, the depth of
the gingival sulcus - 0 mm
The so-called probing depth
of a clinically normal gingival
Sulcus in humans is 2 to 3 mm.
19
20. C) ATTACHED GINGIVA ~
The attached gingiva is continuous with the marginal
gingiva.
It is firm, resilient, coral pink in color and tightly bound
to the underlying periosteum of alveolar bone.(GPT
2001)
It often shows small depressions on the surface. The
depressions, named "stippling", gives the appearance as
of an orange peel.
20
21. The facial aspect of the attached gingiva extends to the
relatively loose and movable alveolar mucosa; it is
demarcated by ‘the mucogingival junction’ .
21
23. WIDTH OF ATTACHED GINGIVA :~
Maxilla incisor region: 3.5- 4.5 mm (greatest)
Mandible incisor region: 3.3 – 3.9 mm
Maxillary premolar: 1.9 mm
Mandibular first premolars: 1.8 mm
The width of the attached gingiva increases with age and in
supraerupted teeth.
The palatal surface of the attached gingiva in the maxilla blends
imperceptibly with the equally firm and resilient palatal mucosa.
23
24. D) INTERDENTAL GINGIVA :
It is the portion of the gingiva that occupies the
interproximal spaces. It is the interdental extension of
the gingiva.(GPT 2001) The interdental gingiva can be
pyramidal, or it can have a “col” shape.
24
25. COL : Valley like depression connecting facial and lingual
papilla.
25
26. MICROSCOPIC FEATURES :
A) GINGIVAL EPITHELIUM :
The gingival epithelium consists of a continuous lining
of stratified squamous epithelium.
*FUNCTIONS*
1. Mechanical , chemical, water and microbial barrier.
2. Signaling function.
26
27. The main function is to protect deep structures which is
achieved by proliferation and differentiation.
mitosis. Biochemical and
morphological events.
27
35. GINGIVAL FIBRES:~
The connective tissue of the marginal gingiva is densely
collagenous, and it contains a prominent system of
collagen fiber bundles called the ‘gingival fibers’.
These fibers consist of type I collagen.
35
36. FUNCTIONS:~
1. To brace the marginal gingiva firmly against the tooth.
2. To provide the rigidity necessary to withstand the
forces of mastication without being deflected away from
the tooth surface .
3. To unite the free marginal gingiva with the cementum
of the root and the adjacent attached gingiva.
36
41. CLINICAL FEATURES:~
COLOUR:
The color of the attached and marginal gingiva is
generally described as “coral pink”.
This is due to –Vascular supply, degree of keratinization,
thickness and pigmentation.
41
42. SIZE :
The size of the gingiva corresponds with the sum total of
the bulk of cellular and intercellular elements and their
vascular supply. Alteration in size is a common feature of
gingival disease.
CONSISTENCY:
Firm and resilient and tightly bound to the underlying bone.
42
43. CONTOUR :
a . Marginal gingiva – Scalloped.
b . Labial surface – accentuated.
c . Lingual surface – Horizontal and thickened.
SURFACE TEXTURE :
Stippled or orange peel appearance.
43
44. POSITION:
The position of the gingiva is the level at which the
gingival margin is attached to the tooth.
When the tooth erupts into the oral cavity, the margin
and sulcus are at the tip of the crown; as eruption
progresses, they are seen closer to the root.
Eruption consists of an active phase and a passive
phase. Active eruption is the movement of the teeth in
the direction of the occlusal plane, whereas passive
eruption is the exposure of the teeth via apical migration
of the gingiva.
44
45. RENEWAL :~
Undergoes continuous renewal.
Thickness is maintained = new cell formation + shedding
of old cells. The following have been reported as
turnover times for different areas of the oral epithelium:
Palate, tongue, and cheek, 5 to 6 days;
Gingiva-10 to 12 days, with the same or more time
required with age;
And junctional epithelium, 1 to 6 days.
45
47. PERIODONTAL LIGAMENT.
The periodontal ligament is composed of a complex
vascular and highly cellular connective tissue that
surrounds the tooth root and connects it to the inner wall
of the alveolar bone.
The average width of the periodontal ligament space is
documented to be about 0.2 mm.
47
48. CELLULAR ELEMENTS :
4 TYPES OF CELLS :
1} Connective tissue cells- a) Fibroblasts
b) Cementoblasts
c) Osteoblasts.
2} Epithelial rest cells.
48
49. 3} Immune system cells-
a) Neutrophils
b) Lymphocytes
c) Macrophages
d) Mast cells
e) Eosinophils.
4} Cells associated with Neuromuscular elements.
49
51. 1) TRANSSEPTAL - Extends interproximally over
the alveolar bone crest and are embedded in the
cementum of adjacent teeth.
They are reconstructed even after destruction of the
alveolar bone that results from periodontal disease.
51
52. ALVEOLAR CREST – Extends obliquely from
cementum just below the junctional epithelium to the
alveolar crest.
Prevents extrusion of teeth.
Resists lateral movement .
52
53. HORIZONTAL - fibers Extend at right angles to the
long axis of the tooth from the cementum to the alveolar
bone.
APICAL - Radiate in a rather irregular manner from
the cementum to the bone at the apical region of the
socket. They do not occur on incompletely formed roots.
53
54. OBLIQUE - Which constitute the largest group in the
periodontal ligament, extend from the cementum in a
coronal direction obliquely to the bone. They bear the
vertical masticatory stresses and transform such stresses
into tension on the alveolar bone.
INTERRADICULAR - Fan out from the cementum
to the tooth in the furcation areas of multirooted teeth.
54
56. Physical Functions :
1. Provision of a soft-tissue “casing” to protect the
vessels and nerves from injury
by mechanical forces.
2. Transmission of occlusal forces to the bone.
3. Attachment of the teeth to the bone.
4. Maintenance of the gingival tissues in their proper
relationship to the teeth.
5. Resistance to the impact of occlusal forces (i.e. Shock
absorption)
56
57. FORMATIVE AND REMODELING
FUNCTION:
Cells of the periodontal ligament participate in the
formation and resorption of cementum and bone, which
occur during physiologic tooth movement, during the
accommodation of the periodontium to occlusal forces,
and during the repair of injuries.
57
58. Nutritional and Sensory Functions :
The periodontal ligament supplies nutrients to the
cementum, bone, And gingiva by way of the blood
vessels, and it also provides lymphatic drainage.
periodontal ligament is abundantly supplied with
sensory nerve fibers that are capable of transmitting
tactile, pressure, and pain sensations via the trigeminal
pathways.
58
60. CEMENTUM.
60
Cementum is specialized, mineralized, avascular
mesenchymal tissue that forms the outer covering of
anatomic root.
Cementum begins at the cervical portion of the tooth at
the cementoenamel junction and continues to the apex.
61. PHYSICAL CHARACTERISTICS:
61
Hardness < Dentin.
Light yellow in color and lacks luster.
Lighter in color than dentin .
The thickness of cementum is approximately 20-50 µm
cervically (Thinest) and 200 µm apically(Thickest).
69. CEMENTOENAMEL JUNCTION -
69
The junction between the cementum and enamel at the
cervical region of the tooth is termed Cemento-Enamel
junction.
Three types of relation exist at the cementoenamel
junction.
72. CEMENTODENTINAL JUNCTION -
72
The terminal apical area of cementum where it joins the
internal root dentin is called Cementodentinal junction or
CDJ.
Width of CDJ is 2 to 3um and remains relatively stable.
74. FUNCTIONS :
74
1) ANCHORAGE –
To furnish a medium for the attachment of collagen
fibers that bind the tooth to alveolar bone.
Connective tissue attachment to the tooth is impossible
without cementum.
75. 75
2) ADAPTATION –
Continuous deposition of cementum is of functional
importance as it makes functional adaptation of teeth
possible.
Cementum is not resorbed under normal conditions.
As the most superficial layer of cementum ages, a new
layer is deposited that keeps the attachment apparatus
intact.
76. 76
3) REPAIR –
Damage to roots such as fractures and resorptions can
be repaired by the deposition of new cementum.
81. 81
1) Alveolar bone proper -
The alveolar bone proper is about 0.1–0.4 mm thick.
It surrounds the root of the tooth and gives attachment
to principal fibers of the periodontal ligament.
It is perforated by many openings that carry nerves and
blood vessels in to the periodontal ligament therefore it
is called cribriform plate
83. 2) Supporting alveolar bone -
83
Supporting alveolar bone is that part of the bone which
surrounds the alveolar bone proper and gives supports to
the socket. - It consists of two parts :
A} Cortical plates
B} Spongy bone :
85. 85
A) Cortical plates ~
It consists of compact bone and form the outer and inner
plates of the alveolar processes.
It is continuous with the bony maxilla and mandible and
is much thicker in the mandible than in the maxilla.
They are thickest in the mandibular premolar and molar
regions especially on the buccal side.
86. 86
B) Spongy bone ~
It fills the area between cortical plates and the alveolar
bone proper.
87. INTERDENTAL SEPTUM :
87
It consists of cancellous bone that is bordered by the
socket wall of approximating teeth and the facial and
lingual cortical plates.
89. ALVEOLAR CREST :
89
Forms when the inner and outer cortical plates meet.
The margin is thin and knife edged of anterior teeth and
rounded in posterior teeth.
Runs roughly parallel to the CEJ 1-3mm apical to it with
greater distance seen as the age progresses.
90. 90
Average distance between CEJ and alveolar crest
1.08mm.
This increases with age- 2.81mm
92. FUNCTIONS :
92
Houses the roots of teeth.
Anchors the roots of teeth to the alveoli .
Helps to move the teeth for better occlusion.
Helps to absorb and distribute occlusal forces generated
during tooth contact.
Supplies vessels to periodontal ligament.
Houses and protects developing permanent teeth, while
supporting primary teeth.
94. 94
The blood supply to the supporting structures of the
tooth is derived from the inferior and superior alveolar
arteries to the mandible and maxilla, and it reaches the
periodontal ligament from three sources: apical vessels,
penetrating vessels from the alveolar bone, and
anastomosing vessels from the gingiva.
95. AGE CHANGES :
95
Thinning and decreased keratinization of the gingival
epithelium have been reported with age.
the width of the PDL space will decrease if the tooth is
unopposed (i.e., hypofunction) or increase with
excessive occlusal loading .
96. 96
An increase in cemental width is a common finding; this
increase may be 5 to 10 times wider than in those of
younger age.
The increase in width is greater apically and lingually.
98. 98
An adequate understanding of the relationship between
periodontal tissues and restorative dentistry is paramount
to ensure adequate form, function, esthetics and comfort
of the dentition
The relationship between periodontal health and the
restoration of teeth is intimate and inseparable.
Maintenance of gingival health constitutes one of the
keys for tooth and dental restoration longevity.
99. 99
BIOLOGICAL WIDTH:
‘ Biological width is the combined width of connective
tissue and epithelial attachment superior to the crestal
bone’. (Gargiulo et al. 1961)
Later on, the term 'biologic width' was introduced by
Cohen to describe the space over the tooth surface,
occupied by the connective tissue and epithelial
attachments and this parameter being equivalent to the
distance between the bottom of the gingival sulcus and
the alveolar bone crest.
100. 100
The total dimension of the epithelial attachment and
connective tissue attachment to the root .
(Assif et al. 1991)
The dimensions of the space that the healthy gingival
tissue occupies over the alveolar bone.
( Carranza 9th edition)
101. 101
The biological width is considered to be essential for
maintaining healthy gingiva, especially in the case of
teeth which needs restoration.
Biological width acts as a barrier to prevent entry of
microorganisms into the periodontium
104. Supragingival margin -
104
It has the least impact on the periodontium. This margin
location has been applied in non-esthetic areas .
ADVANTAGES~
1. Preparation of the tooth and finishing of the margin is
easiest
2. Duplication of the margins with impressions that can be
removed past the finish line without tearing or deformation
is the easiest with supragingival margins.
105. 105
Fit and finish of the restoration and removal of excess
material is easiest
Verification of the marginal integrity of the restoration is
easiest.
The supragingival margins are least irritating to the
periodontal tissue.
107. Equigingival margin -
107
Favour more plaque accumulation than supragingival or
subgingival margins, and therefore result in greater
gingival inflammation.
Any minor gingival recession would create an unsightly
margin display.
109. Subgingival margin -
109
Restorative considerations will frequently dictate the
placement of restoration margins beneath the gingival
tissue crest because of caries or tooth deficiencies, and/or
to mask the tooth/restoration interface.
Sub gingival restorations demonstrated more quantitative
and qualitative changes in the micro flora, increased
plaque index, gingival index, recession, pocket depth and
gingival fluid.
112. 112
According to Kois –
1) Normal Crest.
2) High Crest.
3) Low Crest.
113. 1) Normal Crest .
113
In the Normal Crest patient, the mid-facial measurement
is 3.0 mm and the proximal measurement is a range from
3.0 mm to 4.5 mm. Normal Crest occurs approximately
85% of time. In these cases, the gingival tissue tends to
be stable for a long term. The margin of a crown should
generally be placed no closer than 2.5 mm from alveolar
bone. Therefore, a crown margin which is placed 0.5 mm
subgingivally tends to be well-tolerated by the gingiva,
and is stable long term in the Normal Crest patient.
114. 2) High Crest .
114
High Crest is an unusual finding in nature and occurs
approximately 2% of the time. There is one area where
High Crest is seen more often: In a proximal surface
adjacent to an edentulous site. In the High Crest patient,
the mid-facial measurement is less than 3.0 mm and the
proximal measurement is also less than 3.0 mm . In this
situation, it is commonly not possible to place an
intracrevicular margin because the margin will be too
close to the alveolar bone, resulting in a biologic width
impingement and chronic inflammation.
115. 3) Low Crest .
115
In the Low Crest patient group, the mid-facial
measurement is greater than 3.0 mm and the proximal
measurement is greater than 4.5 mm. Low Crest occurs
approximately 13% of the time. Traditionally, the Low
Crest patient has been described as more susceptible to
recession secondary to the placement of an
intracrevicular crown margin. When retraction cord is
placed subsequent to the crown preparation; the
attachment apparatus is routinely injured. As the injured
attachment heals, it tends to heal back to a Normal Crest
position, resulting in gingival recession.
117. IMPORTANCE :
117
Based on the sulcus depth the following three rules can
be used to place intracrevicular margins:
1) If the sulcus probes 1.5 mm or less, the restorative
margin could be placed 0.5 mm below the gingival tissue
crest
118. 118
2) If the sulcus probes more than 1.5 mm, the restorative
margin can be placed in half the depth of the sulcus.
3) If the sulcus is greater than 2 mm, gingivectomy
could be performed to lengthen the tooth and create a 1.5
mm sulcus. Then the patient can be treated as per rule 1.
119. CROWN CONTOUR :
119
The four guidelines to contouring crowns with emphasis
on access for oral hygiene will be described :
1) Buccal and lingual contours–flat, not fat! –
overcontouring is a greater periodontal hazard than
undercontouring.
120. 120
2) Open embrasures ~
If plaque is a primary etiologic factor in gingivitis, then
every effort should be made to allow easy access to the
interproximal area for plaque control.
Open embrasure spaces will allow for this easy access.
An overcontoured embrasure will reduce the space
intended for the gingival papilla. The result is a broadening
of the col area, causing pressure and irritation on the
papilla.
121. 121
3) Location of contact areas ~
Contacts should be high (directed incisally) and buccal
in relation to the central fossa .
4) Furcations involvement ~
Furcations that have been exposed owing to loss of
periodontal attachment should be ‘‘fluted’’ or ‘‘barreled
out’’
122. PONTIC DESIGN :
122
The pontic design of choice is the modified ridge lap for
posterior spaces and the ridge-lap facing for anterior
spaces.
124. 124
Periodontal indices are often used for evaluation of
dental implants.
periodontal indices for dental implants:
(1) longevity,
(2) mobility versus rigid fixation,
(3) percussion,
(4) pain,
(5) probing depths,
125. 125
(6) bleeding index,
(7) crestal bone loss,
(8) radiographic evaluation,
(9) keratinized tissue, and
(10) periimplant disease.
126. Comparison of Tooth and Implant supported structures
126
Structure Tooth Implant
Connection to bone, Cementum ,bone,
periodontium
Osseointegration,
bone functional
ankylosis
Junctional epithelium Hemidesmosomes
and basal lamina
(lamina lucida and
lamina densa zones)
Hemidesmosomes
and basal lamina
(lamina lucida, lamina
densa, and sublamina
lucida zones)
127. 127
Connective tissue 12 groups: six insert
perpendicular to tooth
surfaces ↓collagen, ↑
fibroblasts
Only two groups:
parallel and circular
fibers; no attachment
to the implant surface
↑ collagen, ↓fibroblasts
Biological width 2.04–2.91 mm 3.08 mm (includes
sulcus)
Vascularity Greater; supraperiosteal,
and periodontal
ligament
Less periosteal
Probing depth 3 mm in health 2.5–5.0 mm (depending
on previous soft tissue
depth)
129. CONCLUSION:
129
Gingival tissues play a key role in the protection of
tooth structures and supporting periodontal tissues
against trauma and/or infection
Making the gingival health, a very essential component
for the success of all periodontal treatment procedures.
130. 130
The health and integrity of the periodontium is vitally
important for dental health and preventing inflammation
and infection and advising about regular and correct
brushing to clean and protect the periodontium is an
essential role for the dental professional.
131. REFERENCES:
131
Clinical Periodontology By Carranza, 12th Edition
Clinical Periodontology And Implant Dentistry By
Jan Lindhe, 4th Edition.
Biology Of Periodontal Connective Tissue – Bartold
And Sampath Narayana
Orbans - oral histology and embryology 13th edition –
GS kumar
Ten cates oral histology 8th edition – Antonio Nanci
132. 132
Periodontology 2000 article –the gingival tissues :the
architecture of periodontal protection. e
Journal of Clinical and Diagnostic Research ·
November 2018; Hari Padmini et al
Malthi k et al ;IJSRR 2013,3(2),188-198.