Histology And Clinical Anatomy Of The Gingiva

Histology And Clinical Anatomy Of The Gingiva

Define oral mucosa. Write in detail the microscopic and macroscopic features of the gingiva. 
Answer:

Definition:

• The moist lining of the oral cavity that communicates with the exterior is called oral mucosa.

Gingiva:

• It is defined as the tissue that covers the alveolus and encircles the necks of teeth.
• It extends from the dentogingivial junction to the alveolar mucosa.
• It is immovable and firmly attached to the periosteum of the alveolar bone.

Microscopic features:

1. Epithelium:

• Thick stratified squamous epithelium.
• The layers observed are:

1. Stratum basale
2. Stratum spinosum
3. Stratum granulosum
4. Stratum corneum.
   • It may be ortho-keratinized or para-keratinized.
   • It shows stippled surface.

2. Junction between epithelium and lamina propria:

• Convoluted
• Presence of plenty of deep rete pegs that are closely placed.
• This prevents the epithelium from being stripped off.

3. Lamina propria:

• Contains long and narrow connective tissue papillae.
  It has a papillary layer and a reticular layer.
• Not highly vascular.
• It is made up of collagen bundles, long capillary loops, lymphatics, nerve tissue, and cells like fibroblasts, histocytes, monocytes, mast cells, and lymphocytes.

4. Submucosa:

• A distinct submucosa layer is absent.
• Lamina propria is directly attached to the periosteum.

Fibers:

Macroscopic features:

• Colour- coral pink normally but it depends on.
  1. Thickness of epithelium
  2. Degree of keratinization
  3. Degree of pigmentation.
  4. Amount of circulation.
• Consistency – firm and resilient
• Contour – scalloped
• Surface -stippling surface.

Parts of gingiva:

1. Free or marginal gingiva:

• Embraces the necks of the teeth.
• Width of free gingiva.
• 1 mm – in normal healthy gingiva

Increased in:

• Chronic marginal gingivitis.
• Chronic periodontitis.
• The dividing line between the free gingiva and the attached gingiva is the free gingival groove.

2. Attached gingiva:

• Part of the gingiva that is firmly bound to tire periosteum
• Boundaries.

1. Superiorly – free gingival groove.
2. Inferiorly – mucogingival line.

• It has a greater width in the maxilla compared to the mandible.
• It is about 4-6 mm.
• Its width decreases in pathological conditions.
• Due to the presence of pockets and gingival recession.

3. Interdental papilla:

• It is that part of the gingiva that fills the space between two adjacent teeth.
• The surface of the interdental papilla is triangular.
• The tip and margins are unattached and the central portion is attached.

Gingival sulcus:

• It is a ‘ V’ shaped space between the marginal gingiva and the tooth surface.
• Its depth is about 0-2 mm normal.
• The base is formed by the superior end of the junctional epithelium.