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• Gingiva


  That part of the masticatory mucosa of the oral mucosa which covers the alveolar bone and root of the tooth to a level above the CEJ in an adult
• Gingiva


  • Functions as a barrier from the penetration of microbes and noxious agents into the deeper tissues
• Parts of the gingiva

  • Marginal gingiva
  • Interdental gingiva
  • Attached gingiva
• Marginal gingiva

  The unattached portion and the terminal edge or border of the gingiva that surrounds the tooth in a collar-like manner in the region of the CEJ
• Marginal gingiva


  • Fits closely to the tooth but is not directly attached to it
  • Can be gently stretched away from the tooth surface with a periodontal probe
  • About 1mm wide and demarcated from the adjacent attached gingiva by a shallow linear depression, the free gingival groove in about 50% of cases
  • Forms the soft tissue wall of the gingival sulcus
• Gingival sulcus


  The space or shallow V-shaped crevice bounded by the lining epithelium of the marginal gingiva on one side and the tooth surface on the other side
• Gingival sulcus

  • Probing depth of a clinically healthy gingival sulcus in humans is 2-3 mm
  • Base of the sulcus is formed by the junctional epithelium, a specialized type of epithelium that attaches to the tooth surface
• Gingival crevicular fluid (GCF)

  Fluid found in the gingival sulcus
• Gingival crevicular fluid (GCF)

  • Can be a transudate or an exudate which contains a wide range of biochemical factors that can be used as a potential diagnostic biomarker of the biologic state of the periodontium in health and disease
  • Mainly composed of epithelium, connective tissue, serum, inflammatory cells, and microbial flora
  • In the state of health, GCF is present in small quantities, whereas in inflammation, GCF increases and presents inflammatory exudates
• Functions of GCF

  Cleansing action<|>Provides adhesion of the gingival epithelium to the tooth as it contains plasma proteins<|>Antimicrobial action<|>Acts as a gingival defense mechanism as it possesses antibody activity
• Attached gingiva

  That part of the gingiva that is tightly connected to the cementum on the cervical third of the root and to the periosteum of the alveolar bone
• Attached gingiva


  • Lies between the marginal gingiva and alveolar mucosa
  • Width differs on different areas of the mouth, widest in incisor and molar regions and narrowest in premolar regions
  • Should not be confused with the width of the keratinized gingiva as the latter also includes the marginal gingiva
  • Allows the gingival tissue to withstand the mechanical forces created during activities such as mastication, speaking and toothbrushing
  • Prevents the marginal (free) gingival from being pulled away from the tooth when tension is applied to the alveolar mucosa
• Interdental gingiva


  The portion of the gingiva that occupies the gingival embrasure which is the area between two adjacent teeth apical to the contact area
• Interdental gingiva

  • Can be pyramidal in shape in the anterior teeth and can have valley-like shape known as "col" in the posterior areas
  • If a diastema is present, the gingiva is firmly bound over the interdental bone and forms a smooth, rounded surface without interdental papillae
• Components of the gingiva

  • Gingival epithelium
  • Gingival connective tissue (lamina propia)
• Gingival epithelium

  A stratified squamous epithelium lining the gingiva
• Gingival epithelium

  • Keratinocytes form the bulk of the gingival epithelium
  • Plays an important role in host defense mechanism by protecting the deep structures through proliferation and differentiation of keratinocytes
  • Contains other cells like Langerhans cells, Merkel cells, and melanocytes in small numbers
• Types of gingival epithelium

  • Oral epithelium
  • Sulcular epithelium
  • Junctional epithelium
• Oral epithelium

  Also known as the outer epithelium that covers the outer surface of the keratinized gingival, i.e., the marginal gingiva and attached gingiva
• Keratinization varies in different areas of the oral cavity
• Epithelium

  Connected to the underlying connective tissue by a basal lamina which is approximately 300-400A thick. It consists of lamina densa and lamina lucida. Hemidesmosomes are attached to the lamina lucida composed mainly of glycoprotein laminin. Type IV collagen forms the bulk of lamina densa.
• Types of gingival epithelium

  • Oral epithelium
  • Sulcular epithelium
  • Junctional epithelium
• Oral epithelium

  • Also known as the outer epithelium that covers the outer surface of the keratinized gingival, i.e., the marginal gingiva and attached gingiva
  • Composed of four layers: stratum basale, stratum spinosum, stratum granulosum, and stratum corneum
  • Keratinization varies in different areas of the oral cavity, being maximum in the palate, gingival, ventral aspect of tongue, cheeks in the descending order
  • Orthokeratinized - surface cells lose their nuclei and presents an impermeable physical barrier to oral bacteria
  • Loses its keratinization if it comes in contact with a tooth
  • Has a wavy interface (epithelial ridges) with connective tissue
• Sulcular epithelium

  • Thin, non-keratinized stratified squamous epithelium that lines the gingival sulcus
  • Extends from the crest of the gingival margin until the coronal portion of the junctional epithelium
  • Semi-permeable, allowing fluid to flow from the gingival connective tissue into the gingival sulcus
  • Lacks stratum granulosum and corneum
  • In health, the junction of the SE and connective tissue has a smooth interface, not wavy and no epithelial ridges
  • Has the capacity to keratinize in certain conditions like: upon exposure to oral cavity and upon complete elimination of inherent bacterial flora
• Junctional epithelium

  • Also referred to as the attachment epithelium which is stratified, squamous and non-keratinizing in nature
  • Found at CEJ in healthy conditions
  • Width of JE is 10-29 cells coronally and 1-2 cells apically and its approximate length is about 0.25 - 1.35 mm
  • Formed by confluence of outer epithelium and reduced enamel epithelium during tooth eruption
  • In health, JE has a smooth tissue interface with the connective tissue
  • Attached to the tooth by internal basal lamina and to the connective tissue by external basal lamina via the hemidesmosomes
  • The junctional epithelium and the gingival fibers together are referred to as the dentogingival unit because the attachment of the junctional epithelium to the tooth is reinforced by the gingival fibers
• Functions of junctional epithelium

  • Acts as a protective barrier against bacterial plaque as it is firmly attached to the tooth surface
  • Acts as a semi permeable membrane as it allows access of gingival fluid, inflammatory cells and immunologic components of the host defense mechanism to the gingival sulcus
  • Helps in the rapid repair of the damaged tissues as cells of the junctional epithelium exhibit rapid turnover
• Gingival connective tissue

  • Also referred as lamina propia and consists of two layers: Papillary layer adjacent to the epithelium and Reticular layer adjacent to the periosteum of the alveolar bone
  • Mainly composed of collagen fibers which are about 60% by volume, fibroblasts (5%) and remaining 35 % is formed by vessels, nerves and matrix
  • Ground substance is mainly composed of proteoglycans like hyaluronic acid, chondroitin sulphate and glycoproteins, mainly fibronectin
  • 3 types of fibers: collagen, reticular, and elastic
  • Type 1 collagen is the main fiber seen in lamina propia and provides tensile strength
  • Elastic fiber is composed of elaunin, elastin and oxytalan fibers distributed among collagen fibers
• Principal gingival fibers

  • Dentogingival group
  • Alveologingival group
  • Dentoperiosteal group
  • Circular group
  • Transseptal group
• Secondary gingival fibers

  • Periosteogingival group
  • Interpapillary group
  • Transgingival group
  • Inter-circular group
  • Inter-gingival group
  • Semi-circular group
• Functions of gingival fibers


  • Hold the marginal gingival tightly against the tooth
  • Provide strength to withstand masticatory forces
  • Unite the marginal gingiva with the cementum an attached gingiva of the adjacent tooth
• Cellular composition of gingival connective tissue

  • Fibroblast is the main cell type, responsible for synthesizing collagen, elastic fibers, glycoproteins and glycosaminoglycans
  • Other cells like mast cells, fixed macrophage and histiocytes are also present
  • Adipose cells and eosinophils which are less in number can also be seen as well as leucocytes and lymphocytes
• Blood supply, lymphatics and nerves of gingiva

  • 3 major sources of blood supply: Supraperiosteal arterioles, Vessels of the periodontal ligament, Arterioles emerging from the crest of the interdental septa
  • Lymphatic drainage progresses to the periosteum of the alveolar process and then to regional lymph nodes (mainly submaxillary group)
  • Nerve supply derived from fibers arising from nerves in the periodontal ligament and from the labial, buccal and palatal nerves
• Age changes in the periodontium

  • Decreased keratinization
  • Reduced or unchanged amount of stippling
  • Decreased connective tissue cellularity
  • Decreased oxygen consumption
  • Increased width of attached gingiva
  • Greater amounts of intercellular substances
  • Atrophy of the connective tissue with loss of elasticity
  • Increase in the number of mast cells
• Gingival fibers originate from cementum and are inserted into connective tissue of gingival and periosteum of the alveolar bone
• Gingival fibers provide stabilization and maintain the position of the teeth in the arch by securing them
• Fibroblast is the main cell type of the gingival connective tissue and is responsible for synthesizing collagen, elastic fibers, glycoproteins and glycosaminoglycans
• Fibroblasts also play an important role in development, maintenance and repair of the gingival connective tissue
• Other cells like mast cells, fixed macrophage, histiocytes, adipose cells, eosinophils, leucocytes and lymphocytes are also present in the gingival connective tissue