Exam 1; Anatomy of the Periodontium Flashcards
What are the four things that compose the periodontium
gingiva
periodontal ligament
root cementum
alveolar bone
What are the two endings of the PDL called
bundle bone when attached directly to bone
Sharpay’s fibers when attached to cementum
What are the two functions of the periodontium
attach the tooth to bony tissue of the jaw
maintain integrity of the masticatory mucosa
The cells that develop into the periodontium originate from where
neural crest (neural tube)
The stoma deal epithelium releases factors which initiate what
epithelial-ectomesenchymal interactions
What two structures does the dental papilla give rise to
the dentin and pulp
What structure does the dental follicle give rise to
the periodontium
This structure determines the shape and form of the tooth
dental papilla
Why do you not bleed upon eruption of the teeth?
because the tooth follows an epithelium lined canal with no vessels
This gives rise to the junctional epithelium
reduced enamel epithelium
The inner cells of the root sheath secrete what
enamel-related proteins; amelogenins
What is the role of amelogenins
it induces differentiation of ectomesenchymal cells of the folic contacting root surface to differentiate into cementoblasts
This is formed by fibroblasts that are differentiated from the dental follicle lateral to the cementum
periodontal ligament
These differentiate from dental follicle ectomesenchymal cells
osteoblasts (alveolar bone proper)
True or False
Ectomesenchymal cells do not remain in the mature periodontium
False; they do and participate in turnover (cementoblasts, osteoblasts, fibroblasts)
This is the part of the masticatory mucosa which covers the alveolar process and surrounds the cervical portion of the teeth
gingiva
What are the three parts of the gingiva
free gingiva
attached gingiva
interdental papilla
This extends from the free gingival margin to the free gingival groove
free gingiva
What type of epithelium is the free gingiva composed of
keratinized epithelium
This is the coronal end of the gingiva; located 1.5-2mm coronal to the CEJ
free gingival margin
This is the junction between the free and attached gingiva corresponding to the CEJ; only found in 30-40% of adults
free gingival groove
This gingival epithelium faces the oral cavity
oral epithelium
This gingival epithelium faces the tooth surface without contacting it
oral sulcular epithelium
This provides contact between the gingiva and the tooth
junctional epithelium
This is the source of the oral sulcular epithelium
oral epithelium
What is the microscopic limits of the free (marginal) gingiva
extending from the FGM to the JE
What is the macroscopic limits of the free (marginal) gingiva)
extending from the FGM to the FGG
Having a firm texture, coral pink in color, and immobile are all properties of what
attached gingiva
What can cause the width to vary regarding the attached gingiva, and where is it the widest/narrowest
increases with age
widest in incisors; narrowest in premolars
mandibular lingual; narrowest in incisors, widest in molars
These are small depressions on the attached gingiva; present in only 40% of adults
stippling
This is the junction between the attached gingiva and the alveolar mucosa
muccogingival junction
True or False
The muccogingival junction extends to the palate
False; there is no muccogingival junction on the palate
Why is there no muccogingival junction on the palate
because there is no alveolar bone; all keratinized tissue
What is the keratinized gingiva composed of
The attached and marginal gingiva
The marginal gingiva is also known as what
the sulcus
If you are measuring 7mm of keratinized gingiva - 4mm sulcus, how much attached gingiva is there`
3mm 7mm keratinized (attached + marginal) - 4mm sulcus (marginal) = 3mm attached
What three things does the shape of the interdental papilla depend upon
the contact relationships between adjacent teeth
width of approximate tooth surfaces
course of CEJ
This is the interdental papilla concavity seen in the contact regions of the premolar/molar; made of non-keratinized epithelium
col
True or False
the col is prone to periodontal disease
True
What becomes of the col upon tooth extraction
it will flatten and keratinize
What are the four layers of the oral epithelium
basal layer (stratum basale)
prickle cell layer (stratum spinosum)
granular cell layer (stratum granulosum)
keratinized cell layer (stratum corneum)
What two things occur from the basal layer to the granular layer
cytoplasmic tonofilaments and number of desmosomes increase
number of organelles increase
What are the two cell types of the oral epithelium
keratinocytes (90%)
clear cells
What three cells make up clear cells
melanocytes
Langerhans cells
Merkel’s cells
This is present between the basal layer of oral epithelium and the CT; 1-2µm wide
basement membrane
What molecules is the basement membrane rich in
glycoproteins
contains protein-polysaccharide complexes
This layer of the basement membrane is adjacent to basal cells
lamina lucida
This layer of the basement membrane is adjacent to connective tissue
lamina densa
These are dense plaques that attach the epithelium to the basement membrane
hemidesmosomes
What causes stippling
fusion of the rete pegs where the connective tissue suppose is lost in thick gingiva (the rete peg is the epithelial projection)
