This document provides an overview of the gingiva, including its macroscopic and microscopic features. It discusses the different types of gingival epithelium (oral, sulcular, junctional), their histological characteristics. It also describes the renewal process of gingival epithelium and cuticular structures. Additionally, it covers the microscopic features of gingival connective tissue and blood supply. Key points include the layers and keratinization process of gingival epithelium, the non-keratinized nature of sulcular and junctional epithelium, and the formation and structure of the dentogingival junction.
seminar on gingiva
contents:
Introduction
Definition
Development of gingiva
Macroscopic anatomy
Microscopic anatomy
Blood supply
Lymphatic drainage
Nerve supply
Correlation of clinical and microscopic features
Repair/healing of gingiva
Age changes
Gingival diseases
Clinical considerations
Conclusion
References
Introduction
A sound knowledge of the anatomy of the periodontium and the surrounding hard and soft structures is essential to determine the scope and possibilities of surgical periodontal procedures and to minimize their risks.
Blood vessels, and nerves located in the vicinity of the periodontal surgical field, are particularly important during various surgical procedures.
Arterial Supply
Common Carotid Artery
Carotid Sinus & Carotid Body
Applied Anatomy of CCA
CAROTID PULSE :
CCA may be compressed against the carotid tubercle of transverse process of C6 vertebra about 4cm above the sternoclavicular joint.
External Carotid Artery
Generally it lies anterior to the Internal Carotid Artery.
It is the chief artery of supply to structures in the front of neck, oral cavity and in the face.
In carotid triangle
Crossed superficially by:
Cervical branch of facial nerve
Hypoglossal nerve
Facial, lingual &superior thyroid vein
Deep to artery lies:
Wall of pharynx
Superior laryngeal nerve
Ascending pharyngeal artery
Above the carotid triangle
ECA lies deep in the substance of parotid gland
Branches
Lingual Artery
Principal artery of tongue.
Arises anteromedially from ECA opposite the tip of greater cornu of hyoid bone.
Divided into three parts by hyoglossus muscle.
Applied anatomy
Sublingual artery injury occurs in premolar & molar region, when sharp instrument or rotating disks slips off a lower molar & injure the floor of mouth.
Sublingual and submental arteries may course anteriorly in close proximity to the lingual plate, and branches of these blood vessels enter accessory foramina along the lingual cortex.
Hofschneider et al (1999)
Inadvertent penetration through the lingual cortical plate into the floor of the mouth while preparing an osteotomy can cause arterial trauma, thereby resulting in development of a sublingual or submandibular hematoma
Flanagan D. et al.2003
Facial Artery
ORIGIN: Arises from the ECA just above the tip of greater cornua of hyoid bone.
COURSE:
Runs upwards in neck as cervical part ;
On face as facial part.
Tortuous course—
In neck allows free movements of pharynx during deglutition,
On face allows free movements of mandible , lips, & cheek during mastication & facial expressions, escapes traction & pressure during movements.
Cervical part :
Cervical part runs upwards on superior constrictor of pharynx deep to the posterior belly of digastric.
It grooves the posterior border of submandibular gland, makes S-bend [2 loops]
1st winding down over submandibular gland &
then up over the base of mandible.
Facial part:
The vessel enters the face by winding around the base of the mandible, and by piercing the deep cervical fascia,at the anteroinferior angle of the masseter muscle, here it can be palpated & is called as anaesthetist’s artery. Using contracted masseter as a landmark, pulse of facia
seminar on gingiva
contents:
Introduction
Definition
Development of gingiva
Macroscopic anatomy
Microscopic anatomy
Blood supply
Lymphatic drainage
Nerve supply
Correlation of clinical and microscopic features
Repair/healing of gingiva
Age changes
Gingival diseases
Clinical considerations
Conclusion
References
Introduction
A sound knowledge of the anatomy of the periodontium and the surrounding hard and soft structures is essential to determine the scope and possibilities of surgical periodontal procedures and to minimize their risks.
Blood vessels, and nerves located in the vicinity of the periodontal surgical field, are particularly important during various surgical procedures.
Arterial Supply
Common Carotid Artery
Carotid Sinus & Carotid Body
Applied Anatomy of CCA
CAROTID PULSE :
CCA may be compressed against the carotid tubercle of transverse process of C6 vertebra about 4cm above the sternoclavicular joint.
External Carotid Artery
Generally it lies anterior to the Internal Carotid Artery.
It is the chief artery of supply to structures in the front of neck, oral cavity and in the face.
In carotid triangle
Crossed superficially by:
Cervical branch of facial nerve
Hypoglossal nerve
Facial, lingual &superior thyroid vein
Deep to artery lies:
Wall of pharynx
Superior laryngeal nerve
Ascending pharyngeal artery
Above the carotid triangle
ECA lies deep in the substance of parotid gland
Branches
Lingual Artery
Principal artery of tongue.
Arises anteromedially from ECA opposite the tip of greater cornu of hyoid bone.
Divided into three parts by hyoglossus muscle.
Applied anatomy
Sublingual artery injury occurs in premolar & molar region, when sharp instrument or rotating disks slips off a lower molar & injure the floor of mouth.
Sublingual and submental arteries may course anteriorly in close proximity to the lingual plate, and branches of these blood vessels enter accessory foramina along the lingual cortex.
Hofschneider et al (1999)
Inadvertent penetration through the lingual cortical plate into the floor of the mouth while preparing an osteotomy can cause arterial trauma, thereby resulting in development of a sublingual or submandibular hematoma
Flanagan D. et al.2003
Facial Artery
ORIGIN: Arises from the ECA just above the tip of greater cornua of hyoid bone.
COURSE:
Runs upwards in neck as cervical part ;
On face as facial part.
Tortuous course—
In neck allows free movements of pharynx during deglutition,
On face allows free movements of mandible , lips, & cheek during mastication & facial expressions, escapes traction & pressure during movements.
Cervical part :
Cervical part runs upwards on superior constrictor of pharynx deep to the posterior belly of digastric.
It grooves the posterior border of submandibular gland, makes S-bend [2 loops]
1st winding down over submandibular gland &
then up over the base of mandible.
Facial part:
The vessel enters the face by winding around the base of the mandible, and by piercing the deep cervical fascia,at the anteroinferior angle of the masseter muscle, here it can be palpated & is called as anaesthetist’s artery. Using contracted masseter as a landmark, pulse of facia
A presentation on the topic of microscopic section of gingiva. This topic is mostly looked on by periodontists. A very important chapter in the speciality in dentistry of periodontology and implantology department. Basic understanding of microscopic features and clinical features of gingiva is an important topic for post graduate as well as undergraduate students in the dental field.
Bone loss and patterns of bone destructionvidushiKhanna1
- introduction
- bone resorption
- factors causing bone destruction in periodontal disease
-- destruction by extension of gingival inflammation
--- histopathology
--- pathways of spread of inflammation
--- radius of action
--- periods of destruction
---- mechanism of destruction
-- bone destruction caused by TFO
-- bone destruction caused by systemic disorders
- factors determining bone morphology in periodontal disease
-- normal variation of alveolar bone
-- exostosis
-- butressing bone formation
-- food impaction
-- agressive periodontitis
- patterns of bone destruction
-- horizontal bone loss
-- vertical or angular defects
-- osseous craters
-- bulbous bone contours
-- reversed architecture
-- ledges
- furcation involvement
-- classification
-conclusion
Dental Plaque
Soft deposits that form the biofilm adhering to the tooth surface or other hard surfaces in the oral cavity, including removable & fixed restorations”
Bowen , 1976
Bacterial aggregations on the teeth or other solid oral structures
Lindhe, 2003
A presentation on the topic of microscopic section of gingiva. This topic is mostly looked on by periodontists. A very important chapter in the speciality in dentistry of periodontology and implantology department. Basic understanding of microscopic features and clinical features of gingiva is an important topic for post graduate as well as undergraduate students in the dental field.
Bone loss and patterns of bone destructionvidushiKhanna1
- introduction
- bone resorption
- factors causing bone destruction in periodontal disease
-- destruction by extension of gingival inflammation
--- histopathology
--- pathways of spread of inflammation
--- radius of action
--- periods of destruction
---- mechanism of destruction
-- bone destruction caused by TFO
-- bone destruction caused by systemic disorders
- factors determining bone morphology in periodontal disease
-- normal variation of alveolar bone
-- exostosis
-- butressing bone formation
-- food impaction
-- agressive periodontitis
- patterns of bone destruction
-- horizontal bone loss
-- vertical or angular defects
-- osseous craters
-- bulbous bone contours
-- reversed architecture
-- ledges
- furcation involvement
-- classification
-conclusion
Dental Plaque
Soft deposits that form the biofilm adhering to the tooth surface or other hard surfaces in the oral cavity, including removable & fixed restorations”
Bowen , 1976
Bacterial aggregations on the teeth or other solid oral structures
Lindhe, 2003
• 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
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
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Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
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The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
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7. Marginal gingiva
The terminal edge / border of the gingiva surrounding the
teeth in collarlike fashion.
Free gingival groove
1 mm wide
1.5- 2mm coronal to CEJ
Incisor & premolar molar
8. Gingival sulcus
Shallow crevice/space around the tooth bounded by the
surface of tooth on one side & the epithelium lining the
free margin of the gingiva on the other side
V shaped
9. Depth of gingival sulcus
Normal/ideal conditions: 0
Gottlieb, Orban 1933
Histologic sections:
1.8 mm (Larjava et al)
1.5 mm (Saito et al)
0.69 mm (Everts et al)
Probing depth: 2-3 mm
10. Attached gingiva
Firm, resilient, and tightly bound to the underlying
periosteum of alveolar bone
Mucogingival junction
Absent on palate
Stippling- orange peel
appearance
11. Width of keratinized gingiva
Distance between the mucogingival
Junction & the projection on the external
surface of the bottom of gingival sulcus
12. 3.5-4.5 mm : Maxilla
3.3-3.9 mm : Mandible
•1.9 mm : Maxilla
•1.8 mm : Mandible
Ainamo J & Loe H 1966
13. Narrow Incisors
Wide Molar region
Range 1-9 mm
17. PREDISPOSING FACTORS
INADEQUATE ATTACHED GINGIVA
• Narrow zone of gingiva is considered insufficient to:
– Protect the periodontium from masticatory forces
– Dissipate the pull because of muscles of adjacent mucosa (Friedman 1957)
• Inadequate zone of gingiva favors:
– Subgingival plaque formation (Friedman, 1962)
– Attachment loss and soft tissue recession due to decreased resistance to apical
spread of plaque associated gingival lesions (Stern, 1976)
– Along with decreased vestibular depth it causes accumulation of food particles
during mastication and impedes oral hygiene measures (Gottsegen, 1954)
18. • Bowers, 1963: Classic study on width of attached gingiva. To clarify meanings of
ADEQUATE / INADEQUATE gingiva.
• Width varied for different teeth and different individuals
• Mean width increased from deciduous to permanent dentition, but changed
little after maturity
• Ranged from 1 – 9mm
• Lowest in the premolar canine region
• Influenced by tooth malposition, frenum attachment and recession
• Recession was most common in 1st premolar-canine, maxillary 1st molar and
mandibular incisor regions
Gingiva could be maintained with <1mm
present
19. • Ainamo and Loe, 1966:
• Band of attached gingiva moved apically with recession by unknown
mechanism
• Greatest width on maxillary and mandibular anteriors
• Lang and Loe, 1972: to determine how much of gingiva id ADEQUATE
(118 randomly selected plaque free surfaces)
Surfaces with <2mm
of keratinized gingiva
Inflammation
Surfaces with > 2mm
keratinized gingiva
80% were clinically
healthy
“2mm of keratinized
gingiva/1mm of
attached gingiva is
adequate to maintain
health”
21. • Miyasato et al., 1977
Study on dental
students
Mid facial plaque
free surface of
mandibular
premolars
Minimal
keratinized gingiva
1mm
Appreciable
keratinized gingiva
2mm
25 days
experimental
gingivitis
Increases in plaque,
gingival exudate and
inflammation were
similar in both
groups
22. • Dorfman et al., 1980 2 year study on 92 patients
Experimental side free gingival grafts
Control side root planing and oral hygiene
instructions every 3 months
Grafted areas had an increase of 4mm of
attached gingiva but no difference in GI, PI and
loss of attachment compared to the controls
Patient can be maintained in gingival health
with excellent oral hygiene and regular
periodontal care at 3 month intervals
23. Interdental gingiva
Occupies gingival embrasure, which is the interproximal
space beneath the area of tooth contact
Determined:
Contact relationships between the teeth
Width of approximal tooth surfaces
Course of the CEJ
31. Morphologic changes:
1. Progressive flattening of the cell with
an increasing prevalence of
tonofilaments
2. Intercellular junctions coupled to the
production of keratohyaline granules
3. Disappearance of the nucleus
Schroeder 1981
32. Stratum Basale:
Cylindric/cuboid.
Contact with basement membrane
Mitotic cell division
Stratum germinativum
Progenitor cell compartment of
the epithelium
1 month
33. Basal lamina : Joins the epithelium to the underlying
connective tissue
300-400 Å
App 400 Å beneath the epithelial basal layer
Produced by the basal cells
Light microscope
Structure less zone
PAS stain positive
37. Stratum granulosum
Keratohyalin granules
Very sudden keratinization of the
cytoplasm of the keratinocyte &
conversion into horny squame
38. Stratum corneum
Filled with keratin
Apparatus for protein synthesis & energy production lost
Complete keratinization Orthokeratinized
Parakeratinized epithelium
Nonkeratinized epithelium
51. Inflammatory cells
Clinical normal areas of mucosa
Lymphocytes : Most frequent
Associated with langerhans cells
Polymorphonuclear leukocytes
Mast cells
52. Difference between attached gingiva &
alveolar mucosa
ATTACHED GINGIVA ALVEOLAR MUCOSA
Keratinized Nonkeratinized
Stippled Unstippled
Deep rete pegs Short,wide rete pegs
Thick lamina propria Thin lamina propria
Few elastic fibers Numerous elastic fibers
Indistinct submucosa Distinct submucosa
Firmly attached Movable
Squier GA, Johnson NW
53. Extracellular matrix
Glycoproteins, lipids, water
Proteoglycans: Hyaluronan, decorin, syndecan
CD 44 – cell surface Hakkinen L
Cell adhesion molecules: ICAM-1, β1 integrin family
Cawford
Serves:
Cell adhesion
Adhesion to tooth surface & basement membrane
Diffusion of water, nutrients & toxic materials
54. Crest & outer surface
0.2-0.3 mm in thickness
Keratinized/parakeratinized
Degree of keratinization
Age & onset of menopause
Palate > Gingiva > ventral aspect of tongue > cheek
Oral epithelium
57. Enzymes: low degree of activity
Acid phosphatase staining negative
Semipermeable membrane
Potential to keratinize:
It is reflected & exposed to oral cavity Bral & Caffesse
Absence of bacterial flora Caffesse
58. The junctional epithelium is the epithelial component of
the dentogingival unit that is in contact with the tooth
surface. The innermost cells of the JE form & maintain a
tight seal against the mineralized tooth surface, the so
called epithelial attachment
Schroeder & Listgarten, 1977
Collar-like band of stratified squamous nonkeratinizing
epithelium
Glickman
Junctional epithelium
60. Current concepts of dentogingival
junction
Upto 1912 Min information regarding junction between
tooth & epithelium
Attachment = CT fibers inserting into
cementum & bone
GV Black 1915 Presence of subgingival space extending
upto CEJ under a loose fitting gingiva
Gottlieb 1921 Presence of a firm attachment (Organic
union) between gingiva & tooth = Epithelial attachment
/epithelansatz
61. Orban 1931 during eruption REE forms epithelial
attachment
Waerhaug 1952 Gingiva seperated from tooth by a
capillary space forming a “Epithelial cuff”
Epithelial attachment Epithelial cuff
62. Orban 1956 Agreed to both concepts & gave term
“Attached epithelial cuff”
Stern 1962 Demonstrated the DGJ in rat incisors
consisting of Basal Lamina & Hemidesmosomes
The above concepts were incorrect
Junctional Epithelium, a tissue capable of forming &
renewing itself continuously throught life
Term JE = Anderson & Stern in 1966
63. Transformation of REE to junctional epithelium:
1-2 years Schroeder & Listgarten
65. Structure of Junctional epithelium
Stratified squamous non-keratinized epithelium
3-4 layers thick
10-20 layers
Tapers: from coronal end
located: CEJ
Length of junctional epithelium:
0.25-1.35 mm
2 strata:
Basal layer
Suprabasal layer
66. Basal cells = face gingival CT
Suprabasal cells = tooth surface
also called as DAT cells (Directly Attached to Tooth)
Salonen 1989
Lymphocytes & macrophages
Sensory nerve fibers
Byers and Holland 1977, Maeda et al,1994
67. Keratins: K19
Stratification specific: K5 & K14
Lack of expression:
Morgan et al : Junctional area is the only stratified
nonkeratinized epithelium in the oral cavity that does not
synthesize K4 or K13
Lack of K6 & K16 : Though turnover of the cells is very
high
68. Interconnections
Few desmosomes only
Occasional gap junctions
Schroeder & Listgarten, 1977 Saito et al, 1981 Hashimoto et
al, 1986
Wide fluid-filled intercellular spaces
Schroeder& Münzel-Pedrazzoli, 1970
69. 3 Zones:
Apical zone germinative characteristics
Middle zone higher density of hemidesmosomes
role in adhesion
Coronal zone numerous intercellular space
increased permeability
71. Histochemical evidence Neutral polysaccharide
Thonard JC
Basal lamina:
Laminin: similar to endothelial & epithelial cells
Lack type IV & VII collagen, perlecan,lamina
fibroreticularis. Salonen & Santti 1985
72. Dynamics of junctional epithelium
Turnover is very high protective & regeneration
Earlier thought epithelial cells facing external basal
lamina divide rapidly
Evidence DAT cells high mitotic activity
DAT cells Role in tissue dynamics & reparative capacity
of JE
73. Mechanism of DAT cell turnover:
Daughter cells replace degenerating
cells on tooth surface
Daughter cells enter exfoliation
pathway & gradually migrate coronally
between basal cells & DAT cells
Epithelial cells move in coronal
direction along tooth surface
Periodontology 2000
Vol 31, 2003
74. Structural & functional features:
Firm attachment: epithelial barrier
Immunologic host defense: Gingival fluid, inflammatory
cells
Rapid cell turnover
Endocytic capacity equal to that of macrophages and
neutrophils
Cho.Garant.2000
76. Renewal of Gingival epithelium
Mitotic activity: 24 hr periodicity
Highest Morning
Nonkeratinized areas
Gingivitis
Lowest Evening
New cell
formation
Shedding
of old cells
77. Cell turnover time:
Palate, tongue, cheeks: 5-6 days
Gingiva: 10-12 days
Junctional epithelium: 1-6 days
Beagrie G S
78. Epithelial repair & regeneration
Gingivectomy & incisional wounds:
Undamaged epithelial cells from wound margin, migrates within hours of
injury
Migrate over exposed connective tissue
New hemidesmosomes are formed
1-2 days = epithelial surface is 2-3 cell thick & str basale forms
By day 5 = wound is fully covered
By day 7 = epithelium has matured & new str corneum formation
Green RJ et al
Periodontal flaps: heals long junctional epithelium
Stahl SS et al
79. Dental cuticular structure
A thin, acellular structure with a homogeneous matrix,
sometimes enclosed within clearly demarcated, linear
borders
Listgarten
Coatings of developmental
origin
Formed as part of tooth
development
Reduced enamel
epithelium
Coronal cementum
Dental cuticle
Acquired coatings
Exogenous origin
Saliva
Bacteria
Calculus
Surface stains
80. Gingival crevicular fluid
Seeps through the thin sulcular epithelium
Cleanse material from the sulcus
Improve adhesion of the epithelium to the tooth
Antimicrobial properties
Antibody activity
91. Clinically normal gingiva : Small foci of plasma cell &
lymphocytes : base of the sulcus
Neutrophils : High numbers in gingival connective tissue
& sulcus
Recently erupted teeth in children : Area below the
junctional epithelium of healthy gingiva : T-lymphocytes
Early defense recognition system
92. As time elapses : B-lymphocytes & plasma cells
Specific antibodies against already recognized antigens,
always present in the sulcus of clinically normal gingiva
100. Functions:
To brace marginal gingiva firmly against the tooth
To provide the rigidity necessary to withstand the forces of
mastication without being deflected away from tooth
surface
To unite the free marginal gingiva with the cementum of
the root & the adjacent attached gingiva
104. Dentogingival fibers
Facial, lingual & interproximal surfaces
Originate at cementum
Fanlike conformation
Interproximally : Extend towards
crest of the interdental gingiva
Provide gingival support
105. Alveologingival fibers
Emanate from periosteum
covering height of alveolar crest
Splay coronally into
substance of the attached gingiva
Attach gingiva to bone
106. Dentoperiosteal fibers
Arise in cementum
Insertion
Crest of alveolar process
Lateral aspect of cortical plate
Anchor tooth to bone
Protect PDL
107. Circular fibers
Marginal & Interdental gingivae
Encircle each tooth
Cuff /Ring like fashion
Purse string manner
Maintain contour & position
of free marginal gingiva
108. Transseptal fibers
Interproximally
Horizontal bundles
Between epithelium at base of the
gingival sulcus & crest of interdental bone
Sometimes classified
as principal fibers
109. Support for interdental gingiva
Secure positions of adjacent teeth
Protect interproximal bone
Maintain integrity of dentition within dental arch
111. Periostogingival fibers
Most abundant of secondary fibres
Originate:
Lateral aspect of alveolar bone
Splay laterally, coronally & apically
Attach gingiva to bone
Provide support & tone
within attached gingiva
112. Interpapillary fibers
Within substance of interdental papilla
Coronal to transeptal fiber
Provide support for interdental gingiva
114. Coronal to CEJ
Maintain tissue consistency, enhance arch alignment &
provide additional support for marginal gingiva
115. Intercircular fibers
Originate from cementum near the distal line angles
Insert into mesial cementum of next distal tooth
Aid in maintaining arch integrity
116. Intergingival fibers
Course in a mesiodistal direction within attached gingiva
Do not insert into any calcified structure
Provide form, support &contour of attached gingiva
117. Semicircular fibers
Form a half-ring about each tooth on both oral and facial
aspects
support free marginal gingiva
118. Ground substance
Fills the space between fibers & cells
Amorphous
Water
Proteoglycan
Glycoprotein
120. Glycoprotein
Fibronectin
Distributed throughout gingival connective tissues
Localized over collagen fibers
Binds fibroblasts to fibers
Mediate cell adhesion & migration
121. Osteonectin, Vitronectin, Elastin & Tenascin
Present diffusely
Near the subepithelial basement membrane in the upper
connective tissue & capillary blood vessels
Laminin
Basal laminae
Attach it to epithelial cells
122. Repair of gingival connective tissue
High turnover rate
Remarkably good healing and regenerative capacity
Generally shows little evidence of scarring after surgical
procedures
Rapid reconstruction of the fibrous architecture of tissues
Melcher 1976
123. Within hours
Wound site stabilized by fibrin clot formation
Heavy infiltrate of neutrophils
Within 3 days
Granulation tissue evident
Heavily infiltrate of inflammatory cells
Fibrin clot is slowly degraded
124. Day 7
Rich in newly formed granulation tissue
Collagen fibers align parallel along root surface
Day 14
Collagen fibers show signs of attachment to root surface
3 weeks
Fully functional connective tissue attachment
Reformation of Sharpey’s fibers
125. Blood supply
Posterior superior alveolar artery
Infra orbital artery
Greater palatine artery
Inferior alveolar artery
127. Supraperiosteal arterioles
Facial & lingual surfaces of alveolar bone
Capillaries extend along sulcular epithelium
Between rete pegs of outer epithelium
Occasional branches
Alveolar bone PDL
Over crest of the alveolar bone
128. Vessels of PDL
Extend into gingiva
Anastomose with capillaries
in sulcus area
129. Arterioles from crest of interdental septa
Extend parallel to crest of bone
Anastomosis
Vessels of PDL
Capillaries in gingival crevicular areas
Vessels that run over alveolar crest
130. Beneath the epithelium
Subepithelial plexus
Thin capillary loops
Terminal hairpin loops
Efferent & Afferent branches
Spirals
Varices
Sometimes linked by cross-communications
132. Sulcular epithelium : Flat anastomosing plexus
Col area : Mixed pattern of anastomosing capillaries &
loops
Absence of inflammation
Regular, repetitive & layered pattern
Inflamed gingival vasculature
Irregular vascular plexus pattern
133. Lymphatics
Remove excess fluids, cellular and protein debris,
microorganisms & other elements
Control diffusion
Resolution of inflammatory processes
134. Lymphatics of connective tissue papillae
Collecting network external to periosteum
Regional lymph nodes
Lymphatics beneath JE
PDL
Accompany blood vessels
135. Labial & lingual gingiva of mandibular incisor region
Submental lymph nodes
Palatal gingiva of maxilla
Deep cervical lymph nodes
136. Buccal gingiva of maxilla
Buccal & lingual gingiva in
mandibular premolar-molar region
Submandibular lymph nodes
137. Nerve supply
Maxillary & Mandibular branches of Trigeminal nerve
Labial aspect of maxillary incisors, canines & premolars
Superior labial branches from infraorbital nerve
Buccal gingiva in maxillary molar region
Posterior superior alveolar nerve
138. Palatal gingiva
Greater palatine nerve
Area of incisors
Long sphenopalatine nerve
139. Lingual gingiva in mandible
Lingual nerve
Labial gingiva of mandibular incisors & canines
Mental nerve
Gingiva at buccal aspect of molars
Buccal nerve
140. Gingival connective tissues
Most nerve fibres : Myelinated
Blood vessels
Gingival innervation : Derived from fibers arising from
nerves in the PDL & from the labial, buccal, and palatal
nerves
141. Nerve structures in connective tissue
Meshwork of terminal argyrophilic fibers
Meissner-type tactile corpuscles
Krause type end bulbs : Temperature receptors
Encapsulated spindles
142. Correlation of clinical & microscopic
features
Color
Size
Contour
Shape
Consistency
Surface texture
Position
143. Color
Attached or marginal gingiva
Coral pink
Vascular supply
Thickness
Degree of keratinization of epithelium
Presence of pigment-containing cell
151. Proximal surfaces relatively flat faciolingually
Roots are close together
Interdental bone thin mesiodistally
Gingival embrasures & interdental gingiva are narrow
mesiodistally
152. Proximal surfaces flare away from area of contact
Mesiodistal diameter of interdental gingiva is broad
Anterior region : Pyramidal
Molar region : Flattened in buccolingual direction
153. Consistency
Firm & Resilient
Tightly bound to underlying bone
Exception : Movable free margin
Collagenous lamina propria
Contiguity with mucoperiosteum
Gingival fibers
154. Surface texture
Stippled
Orange peel
Lingual < Facial surfaces
Absent : Infancy
Appears : About 5 years
until adulthood
Disappear : Old age
156. Degree of keratinization
Low magnification : Rippled surface interrupted by
irregular depressions (50 µm)
Higher magnification : Cell micropits
Adaptive specialization/ Reinforcement for function
Reduction or loss of stippling
Gingival disease
157. Position
Refers to the level at which the gingival margin is attached
to the tooth
JE, OE, REE : Undergo extensive alterations & remodeling
158. Continuous Tooth Eruption
Gottlieb & Orban, 1933
Active eruption : Movement of the teeth in the direction
of the occlusal plane
Passive eruption : Exposure of the teeth by apical
migration of the gingiva
160. Active & passive eruption proceed together
Gottlieb & Orban, 1933
Attrition
Loss of tooth substance
Tooth eruption
Cementum deposited at
apices and furcations of
roots
Bone formed along
fundus of alveolus and at
crest of alveolar bone
161. Passive eruption is divided into 4 stages
Physiologic process Pathologic process
162. Age changes
Gingival Epithelium
Thinning of epithelium
Shklar 1966
Decreased keratinization
Glickman 1950
163. Shape of the Rete pegs (Conflicting results)
Flattening of rete pegs
Shklar 1966
Height of epithelial ridges increased
Wentz 1952
Formation of epithelial cross ridges
Loe & Karring 1972
164. ↑ cell density
Meyer 1956,Ryan 1974
Morphology : Do not change
Wentz 1952
Regeneration time (Conflicting results)
Mitotic activity ↑
Meyer 1956,Gargiulo 1961
Constant
Ryan 1974
Mitotic activity↓
Karring and Loe 1973
165. Location of JE
Health: Apical termination of JE located at CEJ
Dental plaque : Etiological factor in development of
gingivitis
Suami,1971
166. Absence of plaque : Periodontal breakdown does not
occur : periodontal pocket will not occur
Lindhe & Nyman 1975; Axellsson & Lindhe 1978
Continuous presence of plaque & its quantity :
Development & course of periodontal disease
167. Contradicting studies
Apical migration of JE can occur in absence of plaque &
inflammatory cells
Skilleni 1930, Rushton 1951, Beersten et al 1982
Continuous passive eruption theory
Gottlieb and Orban 1933
Age : Gradual physiological recession of gingiva
concomitantly with apical migration of epithelium
168. Recession : Occlusal migration of teeth compensating for
occlusal wear + Stable location of gingival margin
169. In contrast
Recession
Mechanical trauma e.g. tooth brushing
Loe et al 1978
Extrusion of teeth
Batenhorst et al 1974
Occlusal movement of teeth does not imply apical
migration of JE
Manson 1963, Anneroth & Ericsson 1967, Loe 1967
170. Gingival Connective Tissue
Coarser & dense
Rate of maturation changes
Cellular elements
Rate of collagen synthesis
Soluble - Insoluble collagen
Mechanical strength
Denaturing temperature
Collagen stabilization
171. Conclusion
knowledge of architecture of the gingiva, how the tissue
structure develops & how it relates to function is fundamental
importance for understanding the disease process, and for
devising effective therapeutic strategies
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biology of the gingiva. Periodontology 2000, Vol. 24, 2000, 28–55.
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References
Editor's Notes
Unattached gingiva
Artifically opened gingival pocket / gingival crevice
Host reaction
3 different areas
Keratinizd stratified squamous epi
Clear cells
Pg 32 article
functionL UNit
essential
Major role in develop,maintenance & repair of ging ct