Structures of Periodontium Gingiva Flashcards
The periodontium is composed of 4 structures. What are they?
- Ginigva
- Cementum
- Periodontal Ligament
- Alveolar Bone
The gingiva is a specialised epithelium. What are its 4 primary functions?
- Protection
(protect underlying tissue from mechanical injury, harmful chemicals, invading bacteria, and from excessive loss of water) - Sensation
(sensory nerve endings found in skin, eyes, ears, nose, tongue, etc) - Secretion
(secrete chemical substances including enzyme, hormones, and lubricating fluids) - Friction Reduction
(barrier to underlying connective tissue)
Attachment of epithelial cells provides stength to withstand mechanical forces and forms a protective barrier. What are the two main forms of epithelial attachment cell?
- Desmosomes = cell-to-cell connection
2. Hemi-desmosomes = cell to basal lamina connection
What is the basal lamina?
A thin, tough sheet that separates epithelial tissue from underlying connective tissue
What are the different types of connective tissue?
Cartilage Bone / Bone Marrow Tonsils and lymph nodes Fat Dental tissues eg cementum and dentine pulp
What is keratinisation?
The process in which cytoplasm of the outermost epithelial cells is replaced by keratin to make it stronger and waterproof
What is the difference between keratinised and non-keratinised epithelial cells?
Keratinised = Dead surface cells
- No nuceli
- Form tough, resistant layers
- Masticatory mucosa, which includes gingiva, hard palate, and oral
Non-keratinised = living surface cells
- Have nuclei
- Act as a cushion against mechanical forces
- Junctional and sulcular epithelium, floor of mouth, vestibule, inside of cheeks, soft palate, and lips
How do epithelial tissues access blood supply?
Epithelial tissues do not contain blood vessels
Nourishment obtained from underlying blood vessels in connective
What is the interface of the oral epithelium?
The connection between the oral epithelium and the connective tissue
Appears as ridges, known as “rete pegs”, extend from connective tissue into epithelial layer
What are the functions of the interface?
- Increases the surface area between the two issues
- Increases the strength between the two tissues
- Decreases the distance between the blood supply (in connective tissue) and the epithelium
BONUS: blood supply carried through papilla, rete pegs found in healthy gingiva giving stippled appearance
What are the 3 anatomical areas of the ginigval epithelium?
- Oral epithelium
- Sulcular epithelium
- Junctional epithelium
What is the oral epithelium (OE)?
Covers the outer surface of the free gingiva and attached gingiva
Extends from the crest of the ginigval margin to the mucogingival junction
What is the sulcular epithelium (SE)?
Epithelial lining of sulcus
Extends from crest of the gingival margin to the coronal edge of the junctional epithelium (JE)
Forms shallow “pocket” or “cuff” around the tooth (usually 0.5 - 3mm in depth, but deepens and ulcerates with periodontal disease)
What is the junctional epithelium (JE)?
Epithelium that forms the base of the sulcus and joins the gingiva to the tooth surface by hemi-desmosomes
Easiest point of entry for abcteria to invade connective tissue
Gingiva has ability to repair itself
What is the function of the junctional epithelium?
Attaches the gingiva to enamel and/or cementum of tooth
Forms a seal at the base of gingival sulcus or pocket
Serves as a protectvie barrier between plaque (biofilm) and connective tissue of the periodontium
