Gingiva

1. GINGIVA
-DR.TARANNUM.N.DHATTURE
I YEAR PG

2. CONTENTS• Introduction
• Defination
• Clinical features
• Microscopic features
• Junctional epithelium
• Renewal of gingival epithelium
• Cuticular structure of tooth
• Gingival fluid
• Gingival connective tissue
• Gingival fiber
• Blood supply
• Lymphatic supply
• Nerve supply
• Clinical feature
• Continuous tooth eruption

3. INTRODUCTION
• The normal periodontium provides the support necessary to maintain teeth
in function.
• It consist of four principal components.
1. Gingiva
2. Periodontal ligament
3. Cementum
4. Alveolar bone

4. Oral Mucosa
Masticatory Mucosa: Gingiva +Covering of hard palate
Specialized Mucosa: Dorsum of tongue
Oral Mucous Membrane: Lining the remainder of oral cavity

6. DEFINATION
The gingiva is the part of the oral mucosa that covers the alveolar
process of jaws and surrounds the neck of the teeth.
-GLICKMAN 1950
The gingiva is that part of the masticatory mucosa which covers
the alveolar process and surrounding the cervical portion of the teeth.
-Jan Lindhe 6th editon

7. Clinical features
• Anatomically gingiva is divided into three parts
Marginal Gingiva
Attached Gingiva
Interdental Gingiva

9. Marginal Gingiva
• Unattached gingiva
• It is the terminal edge or border of the gingiva that surrounds the teeth in
collar like fashion.(Ainamo J 1996)
• It is demarcated from the adjacent attached gingiva by a shallow linear
depression called free gingival groove.

10. • It is usually 1mm wide.
• Forms the soft tissue wall of gingival sulcus.
• The most apical point of the marginal gingival scallop is called gingival
zenith
• Its apicocoronal and mesiodistal dimension varies from 0.06-
0.96mm(Ainamo J 1976)

11. Gingival Sulcus
• It is shallow cervice or space around the tooth bounded by the surface of the
tooth on one side and the epithelium lining the free margin of the gingiva on
other side.
• V-shaped
• Ideal Condition:-0mm(Gottileb B 1942)
• Histologic depth:-1.8mm(Orban B 1924)
• Clinically:-2-3mm

12. Development Of Gingival Sulcus
• After the enamel formation is complete, the enamel is covered with reduced
enamel epithelium. When the tooth penetrates the oral mucosa REE unites
with the oral epithelium and transforms into the junctional epithelium.
• As the tooth erupts, this united epithelium condenses along the crown, and
the ameloblast, which forms the inner layer of the REE , gradually becomes
squamous epithelial cells.
• According to Schroeder and Listgarten ,this process takes place in between 1
and 2 years.

13. • The gingival sulcus is formed when the tooth erupts into the oral cavity.
• The sulcus consist of the shallow space that is coronal to the attachment of
the junctional epithelium.
• It is bounded by the tooth on one side and the sulcular epithelium on the
other.
• The coronal extent of the gingival sulcus is the gingival margin.

14. Attached Gingiva
• It is continuous with Marginal Gingiva.
• It is firm,resillent,and tightly bound to the underlying periosteum of alveolar
bone.
• The facial aspect of the attached gingiva extends to the relatively loose and
movable alveolar mucosa;demarcated as mucogingival junction

15. • Width of Attached Gingiva=mucogingival junction+projection on the external
surface of the bottom of the gingival sulcus.
• The width of attached gingiva on the facial aspect differs in different areas of
mouth.(Bowers GM 1963)
Incisor Premolar
Maxilla 3.5-4.5mm 1.9mm
Mandible 3.3-3.9mm 1.8mm

16. Significance of attached gingiva:
• Gives support to the marginal gingiva
• Helps to withstand functional stress
• Provides solid base for movable alveolar mucosa
• Helps to prevent soft tissue recession and attachment loss
• Helps in connective tissue attachment

17. Interdental Gingiva
• It occupies the gingival embrasure,which is the interproximal space beneath
the area of tooth contact.
• Anteriorly :pyramidal shape
• Posteriorly: Col shaped
• Shape of gingiva depends upon the presence or absence of a contact point
between the adjacent teeth, distance between the contact point and osseous
crest.(Tarnow et al 1992)

18. • Col is valley like depression that connects the facial and lingual papilla and
conforms to the shape of interproximal contact.(Cohen B 1959)

19. Microscopic Feature
• The gingiva is composed
1.Overlying stratified squamous epithelium
Predominantly cellular
2. underlying central core of connective tissue.
Less cellular and composed primarily of collagen fibers and ground
substance.

20. Gingival Epithelium
• It consist of a continuous lining of stratified squamous epithelium.
• There are three different areas that can be defined from morphologic and
functional point of view.
1. Oral or Outer Epithelium
2. Sulcular Epithelium
3. Junctional Epithelium

21. Functions
• It protects the deep structures while allowing selective interchange with the
oral environment.
• Mechanical, chemical, water, and microbial barrier.
• Signalling function.

23. • The proliferation of keratinocyte take place mitosis in the basal layer and
less frequently in the supra basal layer.
• Differentiation involves the process of keratinization, which consist of
biochemical and morphologic events that occur in the cell as they migrate
from the basal layer.

24. • The main morphological changes include the following
1. The progressive flattening of the cell with an increasing prevalence of
tonofilaments.
2. The couple of intercellular junctions with the production of keratohyalin
granules.
3. The disappearance of the nucleus.

25. • Principal Cell:-Keratinocyte(90%)
• Non keratinocyte/clear cells(10%)
Langerhan cells
Merkel cells
Melanocytes

26. Langerhans Cells
• Dendritic cells.
• Location: Supra basal level
• They belong to mononuclear phagocyte system.
• Contain elongated granules
• They are considered as macrophages with
possible antigenic properties.(DiFranco CF 1985)

27. • They have important role in immune reaction as antigen presenting cells for
lymphocytes
• They contain g-specific granules(Birbeck granules)
• They have marked adenosine triphosphate activity.

28. Merkel Cells
• Location: Deeper layer of the epithelium.
• Harbor nerve ending.
• Connected to adjacent cell by desmosomes.
• Identified as tactile receptors.

29. Melanocytes
• Dendritic cells
• Location: Basal and spinous layer of the gingival epithelium.
• Synthesize melanin in organelles called premelanosomes or melanosomes.
• Melanin granules are phagocytosed and contained within other cells of
epithelium, and connective tissue called melanophages or melanophores.
• Tyrosine dihydroxy phenylalanine(dopa) melanin
Tyrosinase

30. Oral or outer epithelium
• It covers the crest and outer surface of the marginal gingiva and the surface
of attached gingiva.
• 0.2-0.3mm thick.
• It is keratinized or parakeratinized.
• The prevalent surface is parakeratinized. (Biolcati et al 1953)

31. • Keratinization of the oral mucosa varies in different areas in the following
order.
1. Palate (most keratinized)
2. Gingiva
3. Ventral aspect of tongue
4. Cheek(least keratinized)

32. • Composed of four layers.
1. Stratum Basale
2. Stratum spinosum
3. Stratum granulosum
4. Stratum corneum

33. Stratum Basale
• Cells : cuboidal
• It is made up of the cells that synthesize DNA and undergo mitosis.
• The basal cell and the parabasal spinous cell are referred to as stratum
germinative.

34. Stratum Spinosum
• Prickle cell layer.
• Large polyhedral cells with short cytoplasmic processes.
• It contain keratinosomes or Odland bodies.
• Modified lysosomes.
• They contain large amount of acid phosphatase.

35. Stratum Granulosum
• Cells: flatter and wider cells.
• Keratohyalin granules
• The nuclei show sign of degeneration and pyknosis.

36. Stratum Corneum
• Closely packed, flattened cells that have lost nuclei and most other organelles
as they become keratinized.
• The cells are densely packed with filaments developed from tonofilaments.

37. Different types of epithelial surface layer
Orthokeratinized Epithelium
A complete keratinization process
It is similar to superficial horny layer.
No nuclei in stratum corneum.
Well defined stratum granulosum.

38. Parakeratinized Epithelium
Intermediate stage of keratinization.
Stratum corneum retains pyknotic nuclei and
keratohyalin granules are dispersed.
No stratum granulosum.

39. Non keratinized epithelium
No stratum corneum
No stratum granulosum
Superficial cells have viable nuclei.

40. Keratinocytes
• The keratin protein are composed of different polypeptide subunits
characterized by their isoelectric points and molecular weight.
• Basal cell synthesize low molecular weight keratin K19(40KD)
• K1 keratin polypeptide (68KD) is the main component of stratum
corneum.

41. Sulcular Epithelium
• The sulcular epithelium lines the gingival sulcus.
• It is a thin, non keratinized stratified squamous epithelium without retepegs and
extends from the coronal limit of the junctional epithelium to the crest of the
gingival margin.
• It usually shows many cells with
hydropic degeneration.(Biolcati et al 1953)
• Do not contain merkel cells.

42. • Sulcular epithelium has the potential to keratinize if
1. It is reflected and exposed to the oral cavity
2. The bacterial flora of the sulcus is totally eliminated.
• The sulcular epithelium is extremely important because it may act as
semipermeable membrane through which injurious bacterial products pass
into the gingiva seeps into the sulcus. (Thilander H et al 1964)

43. Junctional Epithelium
• The junctional epithelium consists of a colar-like band of stratified
squamous nonkeratinizing epithelium.
• 3-4 layers thick in early life.
• With age it increases, it may be 10 or even 20 layers.
• Lenghth-0.25-1.35mm

44. • The junctional epithelium is formed by the confluence of the oral epithelium
and reduced enamel epithelium during the tooth eruption.
• The junctional epithelium is attached to the tooth surface by the means of an
internal basal lamina.
• It is attached to the gingival connective tissue by an external basal lamina.

45. • Internal basal lamina consist of lamina densa and lamina lucida to which
hemidesmosomes are attached.
• The attachment of junctional epithelium to the tooth is reinforced by the
gingival fibers, which brace the marginal gingiva against the tooth surface.
• The junctional epithelium and gingival fibers are considered together as
functional unit referred to as dentogingival unit .(Lisgarten MA 1970)

46. Renewal Of Gingival Epithelium
• The oral epithelium undergoes continuous renewal.
• Its thickness is maintained by a balance between new cell formation in the
basal and spinous layer and the shedding of old cells at the surface.
• The mitotic activity exhibits 24hrs periodicity.
• The mitotic rate is higher in non keratinized areas and increased in gingivitis.

47. Cuticular Structures Of The Tooth
• The term cuticle describes a thin acellular structure with a homogenous
matrix that is sometimes enclosed within clearly demarcated linear borders.
• It is non mineralized.
• It may be present between the junctional epithelium and the tooth.
• It is proteinaceous.
• Thickness : 0.25µm

48. • Listgarten has classified cuticular structures into coatings of developmental
origin and acquired coatings.
• Acquired coatings : saliva ,bacteria, calculus and surface stain.
• Coatings of developmental origin: REE, the coronal cementum, and the
dental cuticle

49. Gingival Fluid
• The gingival sulcus contains a fluid that seeps into it from the gingival
connective tissue through the thin sulcular epithelium.
1. Cleanse material from the sulcus.
2. Contain plasma protein that may improve adhesion of the epithelium to the
tooth
3. Possess antimicrobial properties.
4. Exert antibody activity to defend the gingiva.

50. Gingival Connective Tissue
• The major component of the gingival connective tissue are
• Collagen fibers(60%)
• Fibroblast(5%)
• Vessels, nerves and matrix(35%)

51. • The connective tissue of the gingiva is known as lamina propria, and it
consist of two layers
1. Papillary layer subjacent to the epithelium that consist of papillary
projections between the epithelial rete pegs
2. Reticular layer that is contiguous with the periosteum of the alveolar
bone.

52. • Connective tissue has a cellular and an extracellular compartment composed
of fibers and ground substances.
• The gingival connective tissue is largely fibrous connective tissue.
• The ground substance fills the space between fibers and cells; it is
amorphous and has high water content.
• It is composed of
• Proteoglycans:hyaluronic acid and chondroitin sulfate
• Glycoproteins :fibronectin

53. • Three types of collagen fibers are
1. Collagen
2. Reticular
3. Elastic
• Collagen type I forms the bulk of the lamina propria and provides the tensile
strength to the gingival tissue.
• Type IV collagen branches between the collagen type I bundles, and is continuous
with the fibers of the basement membrane and blood vessel walls.

54. • The elastic fiber system is composed of: oxytalan, elaunin and elastic fibers
• The densely packed fibers that are anchored into acellular extrinsic fiber
cementum just below the terminal point of junctional epithelium form the
connective tissue attachment.
• The stability of this attachment is the key factor in the limitation of
migration of junctional epithelium.

55. Gingival Fibers
• The connective tissue of the marginal gingiva is densely collagenous and it contain
prominent system of collagen fiber bundles called gingival fibers.
• These fibers consist of type I collagen.
• The gingival fibers have the following 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 attach gingiva.

56. • The gingival fibers are arranged in three groups
1. Gingivodental
2. Circular
3. Transseptal
- Kornfeld R 1939

57. Gingivodental Fiber
• Those on the facial, lingual , and interproximal surfaces.
• 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 a
fanlike conformation towards the crest and outer surface of the marginal
gingiva.
• Interproximally, the gingivodental fibers extend towards the crest of the
interdental gingiva.

58. Circular fibers
• They course through the connective tissue of the marginal and interdental
gingiva and encircle the tooth in ringlike fashion.

59. Transseptal fibers
• They are located interproximally, form horizontal bundles that extend
between the cementum of the approximating teeth into which they are
embedded.
• They lie in the area between the epithelium at the base of gingival sulcus and
the crest of interdental bone.

61. Fibers Of The Secondary Group
• :
1)Periosteogingival Fibers:
-They extend from the periosteum of the alveolar bone to the
attached gingiva.
-They help to attach gingiva to the alveolar bone.
2)Interpapillary Fibers:
-They are seen in interdental gingiva extending in a facio lingual
direction and support the gingival papilla.

62. 3)Transgingival fibers:
-These are seen in and around the teeth with in the attach gingiva.
-They maintain the alignment of the teeth in the arch.
4)Semicircular fibers:
-They run through the facial and lingual gingiva around each tooth.
-The fibers attach to the interproximal surface at the same tooth.

63. 5)Transgingival fibers:
-Fibers that run between two adjacent teeth.
-these fibers are embedded in the cementum of their proximal surfaces and pass around the
tooth in the middle of the two teeth attaches with these fibers.
6)Transseptal Fibers:
-They are located interproximally , they extend from cementum of one tooth to the cementum
of another .
-Their function is to protect the interproximal bone and maintain tooth to tooth contact.

64. Cellular Elements
• FIBROBLAST
Predominant cell.
Found between the fiber bundles.
Mesenchymal in origin

65. Function
Development
Maintenance
Repair of gingival connective tissue.
Synthesize collagen and elastic fibers as well as glycoproteins and
glycosaminoglycans of amorphous intercellular substance.
Also regulate collagen degradation through phagocytosis and secretion of
collagenase.

66. Mast Cells
• They are associated with blood vessels
• Mast cell histamine plays an important role in the inflammatory reaction.
• They degranulate in response to antigen-antibody formation.

67. Blood Supply

68. Blood Supply
1. Supraperiosteal arterioles:
Along the facial and lingual surface of the alveolar bone from which capillaries
extend along the sulcular epithelium and between the rete pegs of the external
gingival surface. (Ambrosini P 2002)
Occasional branches of the arterioles pass through the alveolar bone to the
periodontal ligament run over the crest of the alveolar bone.

69. 2.Vessels of periodontal ligament, which extends into the gingiva and
anastomose with capillaries in the sulcus area.
3.Arterioles,which emerges from the crest of the interdental septa.
(Carranza FA 1996) and extends parallel to the crest of the bone to
anastomose with vessels of the periodontal ligament, with capillaries in the
cervicular area and vessels that run over the alveolar crest.

70. 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 and then moves to the regional lymphnodes, particularly
submandibular group.
• Lymphatics just beneath the junctional epithelium extends into the
periodontal ligament and accompany the blood vessels.

71. Nerve Supply
• Branches of the trigeminal nerve provide sensory and proprioceptive
functions.
• Within the gingival connective tissue most fibers are myelinated and closely
associated with the blood vessels. Luthman J 1988
• Gingival innervation is derived from the fibers that arise from the nerves in
the periodontal ligament and from the labial, buccal, and palatal nerves.
Bernick s 1959

72. • The following nerve structure are present in the connective tissue
1. A meshwork of terminal argyrophilic fibers.
2. Meissner-type tactile receptors
3. Krause-type end bulbs
4. Encapsulated spindles.

73. Clinical features
• Color: Coral pink
Due to:
1. Vascular supply
2. Thickness
3. Degree of keratinization of epithelium.
4. Pigment –containing cells.

75. Pigmentation
• Melanin is a non haemoglobin derived non pigment, with the following
characteristics:
1. Melanin is responsible for normal pigmentation of the skin, the gingiva and
remainder of the oral cavity.
2. Melanin is present in all normal individual, but it is absent or severely diminished
in albinos.
3. Melanin pigmentation in the oral cavity is prominent in black individual.
4. Ascorbic acid directly regulates melanin pigmentation in gingival tissue.

77. Size
• The size of gingiva corresponds with sum total of the bulk of cellular and
intercellular elements and their vascular supply.
• Alteration in a size is common feature of the gingival disease.

78. Contour
• Normally: Scalloped/ Accentuated.
• Papillary: pointed/pyramidal
• Marginal: flat/knife edge.

79. Shape
• The shape of interdental gingiva is governed by the contour of the proximal
tooth surfaces and location and shape of the gingival embrasure.
• Anterior region: pyramidal
• Posteriorly: flattened.

80. Consistency
• Firm and resilient tightly bond to the underlying bone.(except free gingiva)
• The collagenous nature of the lamina propria and its contiguity with he
mucoperiosteum of the alveolar bone determine the firmness of the
attached gingiva.
• The gingival fibers contribute to the firmness of the gingival margin.

81. Surface Texture
• The gingiva present a textured surface similar to that of an orange peel and is
referred as stippled.
• Stippling:
• it is the form of adaptive specialization or reinforcement for function.
• It is best viewed by drying gingiva.
• The attached gingiva is stippled , marginal gingiva is not.

83. • The central portion of the inter dental gingiva is stippled ,but the margin
borders are smooth.
• Stippling is less prominent on lingual surface than facial surface and may be
absent in some persons.
• The surface texture of the gingiva is related to the degree of epithelial
keratinization.

84. Position
• It is at the level at which gingival margin is attached to the tooth.
• During eruption the margin and sulcus are at the tip of crown, as eruption
progresses, they are seen closer to the root.

85. Continuous Tooth Eruption
• According to the concept of continuous eruption, eruption does not cease
when the teeth meet their functional antagonists; rather it is continuous
throughout the life.
• Eruption consist of
1. Active Phase: Movement of the teeth in the direction of occlusal plane.
2. Passive Phase: Exposure of teeth via apical migration of the gingiva.

86. Passive Eruption
• Passive eruption is divided into following four stages.
• Stage 1: The teeth reach the line of occlusion. The junctional epithelium and
base of the gingival sulcus are on the cementum.

87. • Stage 2: The junctional epithelium proliferates so that part is on the
cementum and part is on the enamel. The base of sulcus is still on enamel.

88. • Stage3: The entire junctional epithelium is on the cementum, and base of the
sulcus is on the cementoenamel junction. As the junctional epithelium
proliferates from the crown onto the root, it does not remain at the
cementoenamel junction any longer than at any other area of the tooth.

89. • Stage 4:the junctional epithelium has proliferated farther on the cementum.
The base of the sulcus is on the cementum, a portion of which is exposed.