Periodontal Disease

• Pathogenesis


  The sequence of events that occur during the development of a disease or abnormal condition
• Periodontal disease


  Bacterial infection of the periodontium
• Types of periodontal disease

  • Gingivitis
  • Periodontitis
• • itis


  Suffix meaning inflammation
• Gingivitis


  A bacterial infection that is confined to the gingiva, resulting in reversible destruction to the tissues of the periodontium
• Periodontitis


  A bacterial infection of all parts of the periodontium, including the gingiva, periodontal ligament, bone, and cementum, resulting in irreversible tissue damage
• Periodontal disease is a bacterial infection of the periodontium, while gingivitis and periodontitis are two types of periodontal disease
• Three basic states of the periodontium

  • Health
  • Gingivitis
  • Periodontitis
• Health


  • Normal appearance and function of the periodontium
• Gingivitis


  • Changes in the color, contour, and consistency of the gingival tissues, observed clinically 4-14 days after plaque biofilm accumulates in the gingival sulcus
• Periodontitis


  • Apical migration of the junctional epithelium, loss of connective tissue attachment, and loss of alveolar bone
• The tissue damage in gingivitis is reversible, while the tissue damage of periodontitis is permanent (irreversible)
• Acute gingivitis


  A gingivitis that lasts for a short period of time, characterized by fluid in gingival connective tissues and swollen tissue
• Chronic gingivitis


  Gingivitis that lasts for months or years, with new collagen fibers forming resulting in more fibrotic tissue
• In many cases, gingivitis may persist for years without progressing to periodontitis
• Microscopic periodontitis


  • Junctional epithelium located below normal position, with destruction of extracellular matrix and collagen fibers, thickening of sulcular epithelium, and destruction of alveolar bone
• In health and gingivitis, the crest of the alveolar bone is located approximately 2 mm apical to the cementoenamel junction (CEJ)
• In periodontitis, there is a progressive loss of alveolar bone, with the crest located more than 2 mm apical to the CEJ
• Inflammation


  The body's reaction to injury or invasion by disease-producing organisms, resulting in destruction of all tissues of the periodontium, including alveolar bone
• Horizontal bone loss


  Bone loss occurs in a plane parallel to the CEJ of adjacent teeth, lowering the height of the alveolar bone
• Vertical/angular bone loss


  Bone loss does not occur in a plane parallel to the CEJ of adjacent teeth, resulting in an uneven reduction in bone height
• Localized bone loss


  Bone loss occurs in isolated areas
• Generalized bone loss


  Bone loss occurs evenly throughout the dentition
• Mild bone loss


  20-30% bone loss
• Moderate bone loss


  30-50% bone loss
• Severe bone loss


  More than 50% bone loss
• Lamina dura


  Loss of integrity of crestal lamina dura between adjacent teeth, indicating early bone loss
• Occlusal trauma


  Thickening of lamina dura, widening of periodontal ligament space, increased diffusion of periodontal bone density, and vertical bone loss
• Horizontal bone loss is the most common pattern of bone loss, while vertical/angular bone loss is less common
• Infrabony defect


  Bone loss that occurs in an uneven, oblique direction, mainly affecting one tooth
• Types of infrabony defects

  • One-wall
  • Two-wall
  • Three-wall
• Pathway in Vertical Bone Loss

  1. Into the gingival connective tissue

  2. Into the alveolar bone

  3. Into the periodontal ligament
• Inflammation spreads in this manner because it is the path of least resistance
• Infrabony defect


  • Result when bone loss occurs in an uneven, oblique direction
  • Mainly affects one tooth
  • Classified on the basis of the number of osseous (bony) walls
• Interproximal Osseous Crater


  Contour of Interdental Bone
• Furcation involvement


  • Occurs on a multirooted tooth when the periodontal infection invades the area between and around the roots
  • Results in a loss of alveolar bone between the roots of the tooth
• Furcation Involvement


  • Images of different furcation involvement levels
• Two-wall intrabony defect


  2 walls of bone remaining
• Periodontal Pocket


  A pathologic deepening of the gingival sulcus as a result of: Apical migration of the JE, Destruction of periodontal ligament fibers, Destruction of the alveolar bone
• Suprabony Pocket


  Occurs when there is horizontal bone loss, JE is located coronal to the crest of the alveolar bone