5. INTRODUCTION
Masticatory Mucosa – Gingiva and covering of
the hard palate
Oral Mucosa Specialized Mucosa – Dorsum of the tongue.
Lining Mucosa - Gingiva Part of oral
mucosa that covers the
alveolar processes of the
jaws and surrounds the
necks of teeth.
6. DEFINITION
Common term – Gums
It is a combination of epithelium and connective tissue and is defined as
that portion of oral mucosa which in complete post eruptive dentition of a
healthy young individual, surrounds and is attached to the teeth and alvoelar
processes.
SCHROEDER
Part of masticatory mucosa covering the alvoelar process and the cervical
portions of the teeth.
LINDHE
The mucous membrane, with supporting fibrous tissue, covering the tooth-
bearing border of the jaw are called as gingiva.
MEDICAL DICTIONARY
8. Marginal Gingiva
Unattached Gingiva
Terminal edge or border surrounding to the collar like
fashion.
Free Gingival Groove
Marginal gingiva demarcated from attached gingiva
by a shallow depression.
“ Line of demarcation between free and attached
gingiva ( Orban 1948 )”
Gingival Zenith
Apical point of marginal gingival scallop.
Apicoronal – 0.06 mm
Mesiodistal – 0.96 mm
9. Gingival Sulcus
Shallow crevice or space around the
tooth.
Bounded by surface of tooth on one
side
Epithelium lining the free margin of
gingiva.
Depth Of Sulcus
Normal or ideal conditions : 0
( Gottelib and Orban )
Histologically – 1.8 mm
Ranges from 0-6mm
1.5mm (Saito et al)
0.69mm (Eveerts et al)
Histologic Depth
Depth of
penetration
probe
10. Attached Gingiva
Continuous with marginal gingiva.
Firm, resilient and tightly bound to periosteum.
Mucogingival Junction : Facial aspect of attached gingiva
extends to relatively loose and
movable alveolar mucosa.
11. Width of Attached Gingiva
Distance between mucogingival junction and projection on the external
surface of bottom of gingival sulcus:
Facial aspect: Maxilla Mandible
Incisor Premolar Incisor Premolar
3.5-4.5mm 1.9mm 3.3-3.9mm 1.8mm
12. Methods to measure gingiva
1)Measurement approach
2)Tension test
3)Roll test
4)By using potassium iodide solution
13.
14. Width increases with age
in supraerupted teeth
Lingual Aspect of Mandible - terminates at the junction of lingual alveolar
mucosa.
Palatal Surface - in maxilla it blends imperceptibly with equally
firm and resilient palatal mucosa.
15. Interdental Gingiva
Shape Pyramidal or Col non keratinised
Facial and lingual surfaces tapered
towards interproximal contact area
Mesial and distal – CONCAVE
16. Contact relationships between the teeth & the course
of CEJ
Anterior regions - pyramidal form
Molar regions - flattened in the buccolingual direction
(sagging pup tent)
Col
In the histological section, is covered by a thin non-
keratinized epithelium.
17. Lateral border and tips – Marginal
Gingiva
Intervening portion – Attached
Gingiva
If diastema present – Gingiva is firmly
bound over interdental
bone and forms a
smooth surface
without interdental
papillae.
18. Tissue Biotypes
Ochsenbein & Ross
Scalloped thin & flat thick gingiva
Claffey & Shanley
Thin tissue biotype - gingival thickness of <1.5 mm
Thick tissue biotype - tissue thickness >/+2 mm
Vertical distance between the interdental bone crest & buccal
bone
0.9-1.2mm – ideal for predictive periodontal prognosis
18
19. MICROSCOPIC FEATURES
Overlying - Straited and squamous epithelium Predominantly Cellular
Underlying - Central core connectivity tissue. Less cellular and primarily
collagen fibres.
20. Gingival Epithelium
Historically Epithelial Component act as physical barrier to
infection.
Recent Epithelial cells play an active role in innate host
defense
Functions and Features of Gingival Epithelium
Architectural Integrity : Cell – cell attachments
Basal Lamina
Keratin Cytoskeleton
21. Major cell type - Keratinocyte
Other cell type - Langerhans cells,
Melanocytes,
Merkel cells
Constant Renewal - Replacement of
damaged cells.
Cell – cell attachments - Desmosomes,
adherens junctions,
Tight junctions,
gap junctions
Cell Basal Lamina - Synthesis of basal
lamina components
Hemidesmosome
Modified from Dale BA Peridontal 2000
22. Keratinocyte :
Principal cell type
Main function of gingival epithelium is to protect the deep
structures.
Proliferation of keratinocytes takes place by mitosis in basal
layer and less frequently in suprabasal layers.
Small portion of cells Proliferative Component
Larger portion of cells Migrate to surface
23. Parakeratinization Orthokeratinization
Complete
disintegration of
the nucleus &
cytoplasmic
organelles
Skin
Incomplete
disintegration of
the nucleus &
cytoplasmic
organelles
Oral epithelium
Inflammation of the underlying connective tissue is
partly responsible for the incomplete cornification.
23
25. Process of Keratinization from the basal layer
Flatening of the cell with increased
Prevalance of tonofilaments.
Intercellular junctions coupled to the
production of keratohyalin granules.
Disappearance of the nucleus
SCHROEDER
Gingival Epithelium
Some areas ( outer ) orthokeratinized
other areas Para or non-keratinized
Intermediate stages of keratinization
Progress to maturity under physiologic or
pathologic condition
26. Parakeratinized epithelia The stratum corneum retains pyknotic nuclei
and the keratohyaline granules are dispersed
not giving rise to a stratum granulosum.
Non–Keratinized epithelium Although cytokeratins are major components,
as in all epithelia
27.
28. Structural and Metabolic Characteristics of Gingival Epithelium
Oral Epithelium
Protective in function
Sulcular Epithelium
Junctional Epithelium To maintain tissue health
Epithelial cells are not PASSIVE BYSTANDERS
Metabolically active
Capable of reacting to external stimuli
29. Oral (Outer ) Epithelium : Covers the crest and outer surface of
marginal and attached gingiva.
Prevalence Parakeratinized
1. Stratum Basale
2. Stratum Spinosum
3. Stratum Granulosum
4. Stratum Corneum
30. Degree of Gingival Keratinization with age and onset of menopause
Most Keratinized : Palate
Least : Gingiva and Ventral aspect of tongue, cheek.
Concentration of glycogen in normal gingiva is inversely related to
degree Of keratinization and inflamation.
Sulcular Epithelium : lines gingival sulcus
thin, non-keratinized stratified squamous epithelium
No rete pegs
Lacks stratum granulosum and corneum
31. Contains K4, K13 ( Oesophageal type cytokeratin ) and K19.
Lower degree of enzymes than in outer epithelium.
Acid phosphate staining negative
Has the potential to keratinize
If
1. It is reflected and exposed in
oral cavity.
2. Bacterial flora of sulcus is totally
eliminated
Local irritation of sulcus prevents
sulcular keratinization.
Semi Permeable
32. JUNCTIONAL EPITHELIUM
Collar like band of stratified squamous epithelium
0.25mm-1.35mm
Early life 3-4 layers thick
with age 10 or 20 layers thick
In healthy tissue
tapers from coronal end 10-29 cells
TO
Apical termination 1-2 cells
33. Two layers
1. Basal layer facing connective
tissue.
2. Suprabasal layer extending to
tooth surface.
J.E = O.E + R.E.E
Exhibits lower glycolytic enzyme
activity than outer epithelium.
Lacks acid phosphatase activity.
Attached to the tooth surface by
Internal basal lamina.
Attached to gingival connective
tissue by external basal lamina.
34. Lamina Densa
Internal Basal Lamina
Lamina Lucida ( to which hemidesmosomes
are attached )
Hemidesmosomes :
Firm attachment of cells to internal basal lamina.
Specific sides for signal transduction
Gene expression, cell proliferation, cell differentiation
Organic strands from enamel appear to extend into lamina densa.
35. J.E attaches to afibrillar cementum present on the
crown.
Neutral polysacchrides in zone of epethelial
attachment.
Dentogingival Unit: J.E + gingival fibers
functional unit
Functions:
1) Epithelial barrier against plaque bacteria.
2) It allows access of gingival fluid, inflammatory cells
components of immunologic host defense to gigival
margin.
36. 3)J.E cells exhibit rapid turn over – this contribute to the
host parasite equilibrium and rapid repair of
damaged tissue.
Various Turn
Over Times:
37. Development of gingival sulcus: After enamel formation
is complete, enamel is covered by REE.
When tooth penetrates oral mucosa REE unites
with oral epithelium transforms into JEE.
Transformation of REE into JEE proceeds in an apical
direction without interrupting the attachments to the
tooth ------- occurs at 1 to 2 yrs.
SCHROEDER , LISTGARTEN
Continually self renewing with mitotic activity occurring in
all cell layers.
38. Renewal of gingival epthelium:
Mitotic activity exhibits 24hrs periodicity.
Highest morning
(Nonkeratinized areas, gingivitis)
Lowest Evening
Mitotic Rate Buccal mucosa
Hard Palate
Sulcular Epithelium
JE
Outer surface of marginal gingiva
Attached gingiva
39. Cuticular structures on tooth
Cuticle: Thin acellular structure.
Cuticular structures into coatings of developmental
origin and acquired coatings.
LISTGARTEN
Acquired coatings: Saliva, bacteria, calculus and surface
stains.
Coatings of developmental origin: REE, coronal
cementum and dental
cuticle.
CUTICLE ---------PRESENT BETWEEN JE & TOOTH
40. Gingival fluid:
Transudate or Exudate
Dignostic or Prognostic Biomaker
Contents: Connective tissue epithelium, inflammatory cells, serum,
microbial flora inhabiting gingival margin or sulcus.
Healthy---------------------- GCF
Inflammation-------------- GCF
Functions:
1. Cleanse material from sulcus.
2. Contain plasma proteins.
3. Possess anti microbial properties.
4. Exert antibody activity to defend gingiva.
42. A papillary layer subjacent to the
epithelium Retepegs.
Lamina Propria:
Reticular layer periosteum of
alveolarbone.
Ground substance fills space between fibers and cells & high
content of water.
composed of proteoglycans, hyaluronic acid, chondrotin sulphate.
44. 3 types of fibers: Type I (bulk of lamina
propria)
1) Collagen
Type IV (branches b/n
collagen Type I)
2) Reticular
3) Elastic
Oxytalan Elaunin Elastin
45.
46. Clinical features
Color: coral pink
The attached gingiva is demarcated from the adjacent
alveolar mucosa on the buccal aspect by a clearly
defined mucogingival line.
