gingiva and its details

1. Gingiva
Sampada Deshpande
Shivani Deshpande

2. Introduction:
Definition of Gingiva
Types of gingiva
 Marginal Gingiva
 Attached Gingiva
 Interdental Gingiva
Microscopic Features
Gingival epithelium
 general aspects
 Functions and features

3. Gingiva:
Gingiva is the part of the oral mucosa that covers the alveolar processes of jaws and surrounds the
necks of the teeth .

5. Oral mucosa
Mouth cavity is lined by oral mucosa

6. Gingiva – it is a part of oral mucosa which surrounds the neck of teeth
Clinical features –
Normal gingiva covers the alveolar bone and tooth root to a level just
coronal to the cementoenamel junction.
gingiva is divided into 3 type
 Marginal Gingiva
 Attached Gingiva
 Interdental Gingiva

9. Marginal Gingiva -
Also known as –unattached gingiva
It is a border of gingiva which surrounds the teeth in collar like fashion
In 50% cases a groove or depression is formed which separate marginal gingiva and attached gingiva _
free gingival groove
It is usually about 1 mm wide
Marginal gingiva forms soft tissue wall of gingival sulcus

11. Gingival sulcus -
◦ It is a shallow space around the teeth which is bounded by surface of tooth on one side and
epithelium lining of free margin of gingiva on other side
◦ V –shaped , barely permits penetration of probe .
◦ Under normal condition depth of gingival sulcus is 0mm.
◦ But in clinically healthy human gingiva some depth can be found which is 1.8mm

13. Attached Gingiva
◦ It is continuous with marginal gingiva
◦ It is firm
◦ Tightly bounded to the periosteum of alveolar bone
◦ It extend upto the alveolar mucosa and demarcated by the mucogingival junction
◦ It is absent on palate
◦ Width of attached Gingiva _ Distance between mucogingival junction and projection on the
external surface of the bottom of the gingival sulcus

14. Width of gingiva-
Distance between mucogingival junction and
projection on the external surface of the bottom
of the gingival sulcus
Mucogingival junction remain stationary
throughout adult life .
Changes in the width of attached gingiva are
caused by modification in the position of its
coronal portion
Width of attached gingiva increases with age

16. Interdental Gingiva
It occupies the the gingival embrasure , which is interproximal space beneath the area of tooth contact
It can be pyramidal or can have a col shape
Firstly the tip of one papilla is located immediately beneath the contact point .valleylike depression connects facial
and lingual papilla and conforms the shape of interproximal contact
Shape of gingiva in interdental spaces depends on the contact point between the two adjoining teeth
Presece or absence of some degree of recession decides the variations in normal interdental gingiva


17. Microscopic Features
◦ Gingiva is composed of overlying stratified squamous epithelium and the underlying central core
of connective tissue
◦ epithelium is predominantly cellular in nature , connective tissue is less cellular and composed of
collagen fibres and ground substance

18. Gingival Epithelium
Epithelium cell plays an active role in innate host defense by responding to bacteria in an
interactive manner
 Epithelium participate actively in responding to infection
For eg :epithelial cells may respond to bacteria by increased proliferation , by alteration of cell
signaling events ; changes in differentiation and cell death
 Gingival epithelium is consist of continuous lining of stratified squamous epithelium

19. Three areas of gingival epithelium
 oral/outer Epithelium
 Sulcular Epithelium
 Junctional Epithelium
• The principal cell type of gingival epithelium is –keratinocytes
• Other cell found in it are celar cells / nonkeratinocytes
• Non-keratinocytes include(Langerhans cells , merkel cells ,melanocytes)
Function:
• Main function of gingival epithelium is to protect the deep structures while doing selective
interchange with oral environment which is achieved by proliferation and differentiation of
keratinocytes .

22. Functions & Features of Gingival Epithelium
 Acts as a mechanical ,chemical,water and microbial barrier .
 Signaling function
 Keratinocytes- this cells forms protective layer around tooth
 It contains gingival fibroblast plays imp role in tissue repair and inflammatory response
 Constant renewal –by replacement of damaged cells
 Cell-cell attachment – desmosomes ,tight junctions gap junctions

23. Modification
Proliferation : proliferation of keratinocytes takes place by mitosis in the basal layer and less
frequently in the suprabasal layers , where small portion of cells remain as a proliferative
compartment while large number begin to migrate to the surface
Differentiation :
It involves process of keratinization ,it consist of morphological and biochemical
events that occour in the cell as they migrate from the basal layer

24. Morphologic changes are:
 Progressive flattening of the cells with an increasing prevalence of tonofilaments
 Intercellular junctions coupled to the production of keratohyaline granules
 Disapperance of nucleus
 Complete keratinization process leads to the production of an orthokeratinized superficial layer .
Similar to skin , with no nuclei in stratum corneum and well defined stratum granulosum
 Only some areas of outer gingival epithelium are orthokeratinized and other gingival areas are
covered by parakeratinized epithelium
 Then this areas can progress to maturity or dedifferntiate under different physiologic or
pathologic conditions

25. In parakeratinized epithelia : retain pyknotic nuclei
keratohyaline granules are disappeared
stratum granulosa is not formed
In non keratinized epithelia : stratum granulosa is not formed
corneum is not formed
superficial cells have nuclei
Here major components are cytokeratins

27. Structural and Metabolic Characteristics of Different
Areas of
Gingival Epithelium
The epithelial component of the gingiva shows regional morphologic variations. These include,
1. Oral/outer Epithelium
2. Sulcular Epithelium
3. Junctional Epithelium

28. 1.) Oral epithelium
◦ It covers the crest and outer surface of the marginal gingiva and the surface of the attached gingiva.
◦ On average, the oral epithelium is 0.2 to 0.3 mm in thickness.
◦ It is keratinized or parakeratinized or presents various combinations of both.
◦ The oral epithelium is composed of four layers:
stratum basale (basal layer)
stratum spinosum(prickle cell layer)
stratum granulosum (granular layer)
stratum corneum (cornified layer).

29. 2.) Sulcular Epithelium
◦ The sulcular epithelium lines the gingival sulcus .
◦ It is a thin, nonkeratinized stratified squamous epithelium without rete pegs, and it extends from
the coronal limit of the junctional epithelium to the crest of the gingival margin .
◦ It usually shows manycells with hydropic degeneration.

30. 3.) Junctional Epithelium
◦ It consists of stratified squamous nonkeratinized epithelium.
◦ the number of layers increases with age to 10 or even 20 layers.
◦ It tapers from its coronal end to its apical termination, located at the cementoenamel junction in healthy
tissue.
◦ These cells can be grouped in two strata:
the basal layer facing the connective tissue
suprabasal layer extending to the tooth surface.
◦ Length- 0.25 to 1.35 mm.
◦ It is formed by the confluence of the oral epithelium and the reduced enamel epithelium during tooth
eruption. However, the reduced enamel epithelium is not essential for its formation
◦ The junctional epithelium and the gingival fibers are considered a functional unit, referred to as the
dentogingival unit.
(the junctional epithelium is completely restored after pocket instrumentation or surgery, and it forms around an implant)

31. Development Of Gingiva
Renewal : The mitotic activity exhibits a 24-
hour periodicity, with the highest and lowest
rates
occurring in the morning and evening,
respectively.
Eruption (Passive)

32. Dental Cuticle
• Also called Nasmyth’s
membrane/Enamel Cuticle
• 0.25um

33. Gingival Fluid (Sulcular fluid)
◦ The gingival fluid contains components of connective tissue, epithelium, inflammatory cells, serum, and
microbial flora inhabiting the gingival margin or the sulcus (pocket).
◦ In the healthy sulcus the amount of the gingival fluid is very small. (During inflammation, however, the gingival
fluid flow increases, and its composition start to resemble that of an inflammatory exudate)
◦ The gingival fluid is believed to
(1) cleanse material from the sulcus,
(2) exert antibody activity to defend the gingiva
(3) possess antimicrobial properties, and
(4) contain plasma proteins that may improve adhesion
of the epithelium to the tooth.

34. Gingival Fibers
◦ 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.

35. ◦ Gingival fibres are divided into 3 major groups which are as follows,
I. Gingivodental Group / Dentogingival Group
The gingivodental fibers are those on the facial, lingual, and interproximal surfaces. They are
embedded in the cementum just beneath the epithelium at the base of the gingival sulcus. On the
facial and lingual surfaces, they project from the cementum in fanlike conformation toward the
crest and outer surface of the marginal gingiva, terminating short of the epithelium.
II. Circular Group
The circular fibers course through the connective tissue of the marginal and interdental gingivae
and encircle the tooth in ringlike fashion.

36. III.Transseptal Group
Located interproximally, the transseptal fibers form horizontal bundles that extend between the
cementum of approximating teeth into which they are embedded. They lie in the area between
the epithelium at the base of the gingival sulcus and the crest of the interdental bone and are
sometimes classified with the principal fibers of the periodontal ligament.
Alveologingival fibres – these extend externally to the periosteum of the facial and lingual alveolar bones,
terminating in the attached gingiva or blending with the periosteum of the bone
Semicircular Fibers - attach at the proximal surface of a tooth, immediately below the cementoenamel junction,
go around the facial or lingual marginal gingiva of the tooth, and attach on the other proximal surface of the
same tooth,
Transgingival Fibers - attach in the proximal surface of one tooth, traverse the interdental space diagonally, go
around the facial or lingual surface of the adjacent tooth, again traverse diagonally the interdental space, and
attach in the proximal surface of the next tooth.
Dento-periosteal Fibres

37. A–Dentogingival fibres,
B–Longitudinal fibres,
C–Circular fibres,
D–Alveologingival fibres,
E–Dentoperiosteal fibres,
F–Transseptal fibres,
G–Semicircular fibres,
H–Transgingival fibres,
I –Interdental fibres,
J–Vertical fibres
1 2
3 4

38. Gingival Connective Tissue
-lamina propria
Collagen fibres
Matrix, nerves and vessels
Fibroblasts
60%
35%
5%

40. The ground substance
It is composed of
◦ Proteoglycans – mainly hyaluronic acid and chondroitin sulfate
◦ Glycoproteins - mainly fibronectin, laminin, tenascin.
Glycoproteins account for the faint PAS-positive reaction of the ground substance.
Fibronectin mediate cell adhesion and migration.
Laminin, found in the basal lamina, serves to attach it to epithelial cells
Connective
tissue fibres
Elastic
Elaunin Elastin
Reticular
Oxytalan
Collagen
Types 1 and 4

41. Blood Supply, Lymphatics, and Nerves
Blood Supply
1. Supraperiosteal arterioles along the facial and lingual surfaces of the alveolar bone, from which capillaries extend
along the sulcular epithelium and between the rete pegs of the external gingival surface.
2. Vessels of the periodontal ligament- which extend into the gingiva and anastomose with capillaries in the sulcus area.
3. Arterioles, which emerge from the crest of the interdental septa anastomose with capillaries in the gingival
crevicular areas and with vessels that run over the alveolar crest.
◦ Beneath the epithelium on the outer gingival surface, capillaries extend between the epithelial rete pegs in
the form of terminal hairpin loops.
◦ Flattened capillaries serve as reserve vessels
◦ Along the sulcular epithelium, capillaries are arranged in a flat, anastomosing plexus.
◦ In the col area, a mixed pattern of anastomosing capillaries and loops occurs.

42. Arteriolar plexus at Sulcular Epithelium
Supra-periosteal Artery

43. Lymphatic Drainage
The lymphatic drainage of the gingiva brings in the lymphatics of the connective tissue papillae.
◦ It progresses into the collecting network external to the periosteum of the alveolar process, then to the
regional lymph nodes.
◦ In addition, lymphatics just beneath the junctional epithelium extend into the periodontal ligament and
accompany the blood vessels.
◦ The numerous lymph vessels of the gingiva finally lead to the submental and submandibular lymph nodes

44. Neural elements
◦ Within the gingival connective tissues, most nerve fibers are myelinated and are closely associated with the
blood vessels.
◦ Gingival innervation : derived from fibers arising from nerves in the periodontal ligament and from the labial,
buccal, and palatal nerves.
The following nerve endings are present in the connective tissue:
a meshwork of terminal argyrophilic fibers
Meissner-type tactile corpuscles
Krause-type end bulbs (temperature receptors)
encapsulated spindles (pressure and vibration)

45. CORRELATION OF CLINICAL AND
MICROSCOPIC FEATURES
Color
◦ The color of the attached and marginal gingiva is generally described as “coral pink”
◦ It is produced by,
the vascular supply
the thickness
degree of keratinization of the epithelium, and
the presence of pigment-containing cells (melanocytes)
◦ The color varies among different persons
◦ The alveolar mucosa is red, smooth, and shiny rather than pink and
stippled.

46. Alveolar Mucosa Gingiva
It is Non-keratinized It is Keratinized
Sub-mucosa is present Sub-mucosa is absent
Reticular layer is absent in lamina propria both reticular and papillary layers are seen in lamina
propria
The papillae are low The Epithelial ridges and papillae are high
Mixed glands are present Secretory glands are absent.

47. Physiologic Pigmentation (Melanin)
◦ Melanin, is responsible for the normal pigmentation ofthe skin, gingiva, and remainder of the oral mucous
membrane.
It is absent or severely diminished in albinos. Melanin pigmentation in the oral cavity is prominent in black
individuals
◦ Oral repigmentation refers to the clinical reappearance of melanin pigment after a period of
clinical depigmentation of the oral mucosa resulting from chemical, thermal, surgical,
pharmacologic, or idiopathic factors.

48. Contour
◦ The contour of the gingiva varies considerably and depends on
the shape of the teeth and their alignment in the arch
the location and size of the area of proximal contact, and
the dimensions of the gingival embrasures.
◦ The marginal gingiva envelops the teeth in collarlike fashion and follows a scalloped outline on the facial and
lingual surfaces.
◦ It forms a straight line along teeth with relatively flat surfaces.
◦ On teeth in lingual version, the gingiva is horizontal and thickened

49. Thickened, shelf-like contour of gingiva in lingual
version
Shape of the inter-dental papilla, co-related to that of the
teeth and gingival embrasure

50. Shape
◦ The shape of the interdental gingiva is governed by the contour of the proximal tooth surfaces and
the location and shape of gingival embrasures
◦ The height of the inter-dental gingiva varies with the location of the proximal contact.
◦ Thus, in the anterior region of the dentition, the interdental papilla is pyramidal in form, whereas the papilla is
more flattened in a buccolingual direction in the molar region.
Consistency
◦ The gingiva is firm and resilient and, with the exception of the movable free margin, tightly bound to the
underlying bone
◦ The collagenous nature of the lamina propria and its contiguity with the mucoperiosteum of the alveolar bone
determine the firmness of the attached gingiva.
◦ The gingival fibers also contribute to the firmness of the gingival margin.

51. Position
◦ The position of the gingiva refers to the level at which the gingival margin is attached to the tooth.
Surface Texture
◦ The gingiva presents a textured surface similar to an orange peel and is referred to as being stippled
◦ Stippling is a form of adaptive specialization for function and is best viewed by drying the gingiva.
◦ The attached gingiva is stippled; the marginal gingiva is not. The central portion of the interdental papillae is usually
stippled, but the marginal borders are smooth.
◦ Stippling is less prominent on lingual than facial surfaces and may be absent in some persons.
◦ At low magnification, a rippled surface is seen, interrupted by irregular depressions 50 μm in diameter. At higher
magnification, cell micropits are seen.
◦ Reduction or loss of stippling is a common sign of gingival disease.
◦ When the gingiva is restored to health after treatment, the stippled appearance returns.
◦ The degree of keratinization and the prominence of stippling appear to be related