Oral Mucosa II Flashcards
1
Q
What’s special about the lip in regards to epithelium/mucosa present?
A
- Consists of skin, specialised mucosa transition zone (vermillion border) and labial oral mucosa (inner side)
2
Q
Are striated muscles present in the lip?
A
- YES
- Striated muscles of facial expression in the lip core
3
Q
Are Minor Salivary glands in the Submucosa?
A
- YES
- Beneath the Oral Mucosa
4
Q
What are the characteristics of the Lip skin?
A
- Keratinised epidermis
- CT dermis
- Hair follicles
- Sebaceous glands
- Sweat
5
Q
What are the characteristics of the Vermilion Zone?
A
- Lacks skin appendages
- Occasional sebaceous glands (corner of the mouth)
- No mucous glands (needs constant moistening)
- Keratinised epithelium
6
Q
What’s the junction between the Vermilion zone and Oral Mucosa called?
A
- Intermediate zone
- Parakeratinised
7
Q
What are the characteristics of the Labial Mucosa?
A
- Covered in thick, non-keratinised epithelium
- Lamina Propria is wide but the Papillae are short and irregular
- Submucosa with minor salivary glands
- Dense CT fibres bind the mucosa to the Orbicularis Oris muscle
8
Q
The Cheek: What are its characteristics?
A
- Non-keratinised epithelium
- Lamina Propria is dense with short and irregular papillae
- Submucosa with many minor salivary glands (biccinator muscles my lay beneath)
- Sebaceous glands sometimes present - become more obvious after puberty
9
Q
What’s the Linea Akba Buccalis?
A
- Keratinised line in the buccal mucosa along the occlusal plane
- Low grade irritation
10
Q
What are Ectopic Sebaceous glands?
A
- Fordyce’s granules
- Out of place glands
- Don’t cause problems
11
Q
Whats the Gingiva?
A
- Portion of the Oral Mucosa that surrounds and is attached to the teeth
12
Q
What are the 2 main regions of Gingiva?
A
- Attached Gingiva
- Directly bound to the alveolar bone and the tooth
Coronal to the Attached is…
- Free Gingiva
- Narrow rim of mucosa, not bound to any underlying hard tissue
13
Q
What is the boundary between the attached and free gingiva called?
A
Free Gingival Groove
-Shallow groove
14
Q
What’s the Gingival Sulcus?
A
- The unattached region between the free gingiva and the tooth
15
Q
What’s Junctional Epithelium?
A
- Area apical to the Gingiva Sulcus
- Where the gingiva is bound to the underlying tooth
16
Q
How is the attached gingiva demarcated from the alveolar mucosa?
A
- Mucogingival junction
17
Q
The Attached Gingiva: What are some of its characteristics?
A
- External surface is masticatory mucosa
- Keratinised
- 75% of the surface maybe parakeratinised
- Papillation varies
- Stippled surface (arise form intersecting epithelial ridges
- No submucosa
18
Q
The Free Gingiva: What are some of its characteristics?
A
- Can be demarcated from the attached gingiva by the free gingival groove
19
Q
What’s the gap between the Enamel and Free Gingiva called?
A
- Gingival Sulcus
- 0.5-2mm in depth
- Lined by Sulcular Epithelium - folded interface with the lamina propria
20
Q
The Junctional Epithelium: What are some of its characteristics?
A
- Epithelial collar that surrounds the tooth and extends from the CEMENTO-ENAMEL JUNCTION to the bottom of the GINGIVAL SULCUS
- High rate of turnover
- Exfoliates coronally
21
Q
What’s special about Junctional Epithelium?
A
- It has 2 Basal Lamina
- Adjacent to the Enamel = attach via hemidesmosomes and a basal lamina produced by the cells) = Epithelial attachment
- Adjacent to the Lamina Propria = same method
22
Q
What are the 2 layers of the Junctional Epithelium?
A
- Stratum Basale
2. Stratum Spinosum
23
Q
How does the length of the Junctional Epithelium vary over time?
A
- At tooth eruption, most enamel is covered
- 1/4 of enamel is covered by the time the tooth reaches occlusion
- Gum recession causes the apical migration of the Cemento-enamel junction
24
Q
What’s Cervicular Fluid?
A
- Fluid found within the sulcus - results from the permeability of the junctional epithelium
- Important in the defence mechanism
- Passes continuously from the subepithelial tissue into the gingival sulcus
- Composition is an indicator of the health state of underlying periodontium
25
What's Interdental Papilla?
- Part of gingiva between adjacent teeth
- Shape arrangement depends on shape and contact between teeth
- Pointed between anterior teeth
- Fills the contour around the contact point
26
What's the Col?
- Continuous with the junctional epithelium
- Non-keratinised
- Proximal surfaces (Distal and Mesial)
27
Gingival Lamina Propria: What's its composition?
- Contains dense bundles of collagen whose function is to support the free gingiva
- Binds attached gingiva to the alveolar bone and tooth
- Link teeth to one another
- Contain less contractile proteins, ground substance, Type III collagen
- Collagen bundles are called PRINCIPLE FIBRES
28
What are the 10 Principle Fibres? (1)
1. Dentogingival Fibres
| - Run from just above the alveolar crest on the root to the gingiva
29
What are the 10 Principle Fibres? (2)
2. Longitudinal Fibres
| - Extend throughout the entire arch
30
What are the 10 Principle Fibres? (3)
3. Circular Fibres
- Encircle each tooth within the marginal and interdental gingiva
- Some attach to the cementum/alveolar bone
31
What are the 10 Principle Fibres? (4)
4. Alveologingival Fibres
| - Run from the Alveolar crest, coronally into the overlying lamina propria of the gingiva
32
What are the 10 Principle Fibres? (5)
5. Dentoperiosteal Fibres
- Only in Labial/Buccal/Lingual gingiva
- Arise from Cementum and pass over Alveolar Crest to insert into the Periosteum
33
What are the 10 Principle Fibres? (6)
6. Transseptal Fibres
- Pass horizontally from the root of one tooth, over the alveolar crest to be inserted into the root of the adjacent tooth
- Provide anatomical basis for linking teeth in the dentition
- Implicated in mesial drift (movement of teeth in Orthodontics and after tooth removal)
34
What are the 10 Principle Fibres? (7)
7. Semicircular Fibres
- Arise from cementum near the CEJ, cross the free marginal gingiva and insert into a similar position on the opposite tooth
35
What are the 10 Principle Fibres? (8)
8. Transgingival Fibres
- Reinforce the circular and semicircular fibres
- Arise from the cervical cementum and extend into the marginal gingiva of the adjacent tooth, merging with the circular fibres
36
What are the 10 Principle Fibres? (9)
9. Interdental Fibres
- Pass through the coronal portion of the interdental gingiva in a buccolingual direction
- Connect Buccal and Lingual gingiva
37
What are the 10 Principle Fibres? (10)
10. Vertical Fibres
| - Arise from attached gingiva or alveolar mucosa and pass coronally towards the marginal gingiva and interdental papilla
38
Alveolar Mucosa: What are its characteristics?
- Demarcated from the keratinsied attached gingiva via the MUCOGINGIVAL JUNCTION
- Non-keratinised
- Loose submucosa and elastin - slightly mobile
- Rich blood supply near the surface = red appearance
- Contains minor salivary glands
