Periodontal Disease: Gingivitis and Periodontitis

Periodontal Disease

• Periodontal disease refers to a bacterial infection affecting the periodontium
• Two main types of periodontal diseases are Gingivitis and Periodontitis

Gingivitis vs Periodontitis

• Gingivitis involves a bacterial infection confined to the gingiva, which results in reversible tissue damage
• Periodontitis is a bacterial infection affecting all parts of the periodontium resulting in irreversible tissue damage, including the gingiva, periodontal ligament, bone, and cementum.
• It is important not to confuse periodontal disease and periodontitis, as gingivitis and periodontitis are types of periodontal disease.

The Three Basic States of the Periodontium

• Health, Gingivitis, and Periodontitis

Gingivitis

• A type of periodontal disease characterized by changes in the color, contour, and consistency of the gingival tissues.
• Clinically observed 4 to 14 days after plaque biofilm accumulates in the gingival sulcus.
• It is a gingivitis that lasts for a short period of time and is characterized by fluid in gingival connective tissues, resulting in swollen tissue.
• Chronic Gingivitis lasts for months or years and leads to the formation of new collagen fibers resulting in more fibrotic tissue
• The tissue damage is reversible since the body can repair the damage
• Gingivitis may persist for years without progressing to periodontitis

Periodontitis

• A type of periodontal disease characterized by:
  • Apical migration of the Junctional Epithelium (JE)
  • Loss of connective tissue attachment
  • Loss of alveolar bone
• The tissue damage is permanent.

Microscopic Periodontitis

• The Junctional Epithelium (JE) is located below the normal position
• The coronal portion of the JE detaches from the tooth, and the extracellular matrix and collagen fibers are destroyed
• Extends ridges into connective tissue
• Surface Epithelium (SE) of the pocket thickens
• Features small SE ulcerations exposing inflamed underlying connective tissue
• Complete collagen destruction occurs in area of inflammation
• Epithelium grows over the root surface where fiber bundles have been destroyed
• Displays widespread destruction of supragingival fiber bundles
• Transseptal fiber bundles continue to regenerate and separate diseased site from bone
• Alveolar bone is destroyed resulting in tooth mobility
• Exhibits permanent destruction of periodontal ligament fibers
• Cementum becomes exposed to plaque biofilm
• In severe destruction cases, the pulp may become inflamed, edematous with vascular congestion, causing dentin demineralization

Changes in Alveolar Bone

• The body reacts to injury or invasion by disease-producing organisms through inflammation.
• The inflammatory process occurs in periodontal disease, leading to the destruction of all tissues, including alveolar bone
• The crest of the alveolar bone is around 2mm apical to the CEJs.

Alveolar Bone Changes

• In gingivitis, the crest of the alveolar bone remains approximately 2 mm apical to CEJs, and the JE is at its normal level.
• In periodontitis, bone destruction may be severe.

Alveolar Bone Loss

• Periodontitis involves progressive bone loss.
• Leads to bone destruction and eventual tooth loss

Patterns of Bone Loss

• Horizontal bone loss
• Vertical bone loss

Horizontal Bone Loss

• The most common pattern of bone loss, resulting in a fairly even, overall reduction in the height of the bone
• The margin of the alveolar crest remains mostly perpendicular to the long axis of the tooth

Vertical Bone Loss

• Less common and results in uneven reduction in bone height, with more rapid progression of bone loss next to the root surface
• A trench-like area of missing bone alongside the root

Pathways of Inflammation into the Bone

• In horizontal bone loss, inflammation spreads to the gingival connective tissue, alveolar bone, and periodontal ligament
• Inflammation spreads this way because it is the path of least resistance

Vertical Bone Loss Pathway

• Includes the gingival connective tissue
• Extends directly into the PDL space and the alveolar bone, occurring when the crestal periodontal ligament fibers are weakened and no longer act as an effective barrier to inflammation

Bone Defects

• Infrabony defects are classified based on the number of osseous (bony) walls, with the following types
  • 3-wall bony defect which has 3 walls of support and the best prognosis
  • 2-wall bony defect has 2 walls of support
  • 1-wall bony defect with 1 wall of support, with the worst prognosis compared to a 3-wall defect

Osseous Crater

• Represents a contour of interdental bone.

Furcation Involvement

• Occurs on multirooted teeth when the periodontal infection invades the area between and around the roots, resulting in a loss of alveolar bone between the roots of the tooth

Gingival Pockets

• Represents a deepening of the gingival sulcus as a result of inflammation, with no apical migration of the JE
• Coronal portion of the JE detaches from the tooth resulting in a slight increase in probing depth and swelling of the gingival tissue increasing probing depth
• No apical migration of JE
• The JE remains coronal to the CEJ
• Also called pseudopockets (false pocket) since there is no destruction of PDL fibers or alveolar bone

The Periodontal Pocket

• A pathologic deepening of the gingival sulcus as a result of apical migration of the JE, destruction of periodontal ligament fibers, and destruction of the alveolar bone
• Suprabony and Infrabony

Suprabony Pocket

• Occurs with horizontal bone loss, where the JE is located coronal to the crest of the alveolar bone.

Infrabony Pocket

• Occurs when there is vertical bone loss, with the JE located apical to the crest of the alveolar bone
• The base of the pocket is located within the cratered-out area of bone alongside the root surface

Disease Sites

• Attachment loss, which refers to the destruction of the fibers and alveolar bone supporting the teeth
• The base of a pocket may exhibit a very irregular pattern of tissue destruction
• A disease site is an area of tissue destruction
• Involves only one surface of the tooth, several surfaces, or all four surfaces
• Can be active or inactive

Active Disease Site

• A disease site that shows continued apical migration of the junctional epithelium over time
• For example, a reading on the distal surface of the mandibular right first molar from 5 mm increases to 6 mm after 3 months

Inactive Disease Site

• A disease site with no net change, with the attachment level of the JE remaining at the same level for a period of time
• For example, the deepest reading on the distal surface of the mandibular right first molar has remained at 5 mm for 12 months.

Periodontal Pockets

• An area of tissue destruction left by the periodontal disease process
• Like a demolished house left after a hurricane
• It is an indicator of past destruction from periodontitis but doesn't automatically mean the site remains active
• The majority of periodontal pockets in most adult patients with periodontitis are inactive sites