Periodontal Anatomy - part 1 Flashcards
What four structures make up the perodontium?
- Gingiva
- Periodontal ligament
- Root cementum
- Alveolar bone
What two process make up the alveolar bone?
- alveolar bone proper (ABP) - also called “bundle bone”
2. alveolar process
What are the two functions of the periodontium?
- attach the tooth to bony tissue of the jaw
2. maintain integrity of masticatory mucosa
T/F. Development of the periodontal tissue occurs after the development and formation of teeth.
False, periodontal tissues develop DURING the development and formation of teeth.
Periodontal development starts early in the ___ phase when cells from the ___ ___ (neural tube) migrate into the ___ branchial arch.
embryonic; neural crest; first
Neural crest cells form a band of ___ beneath the ___ epithelium. The epi releases factor which initiates ___-___ interactions.
ectomesenchyme; stomadeal; epithelial-ectomesenchymal
Following the formation of the dental lamina, what series of processes are initiated which result in the formation of a tooth and its surrounding periodontal tissues, including the alveolar bone proper?
bud stage
cap stage
bell stage with root development
During the cap stage, condensation of ectomesenchymal cells condense around the ___ ___ to form the ___ ___, which gives rise to the dentin and pulp and ___ ___, that forms the periodontium.
dental organ; dental papilla; dental follicle
What determines the shape and the form of the tooth?
dental papilla
What tooth structure forms first?
crown
Outer and inner enamel epithelium cells proliferate apically forming a double layer of cells named ___ ___ ___ ___.
Hertwig’s epithelial root sheath
which cells form dentin?
odontoblast
Inner cells of the root sheath secrete what type of protein?
enamel related proteins (amelogenins)
Following the secretion of amelogenins, the root sheath ___ and ectomesenchymal cells of the ___ ___ penetrate through to contact the root surface.
fenestrates; dental follicle
What induces ectomesenchymal cells of the dental follicle to differentiation into cementoblast?
amelogenin
T/F. As the cementoid forms, fibers of the cementoid intermingle with immature dentinal fibers.
True.
The ___ ___ is formed by ___ that are differentiated from dental follicle lateral to the cementum.
periodontal ligament; fibroblasts
___ differentiate from dental follicle ectomesenchymal cells (alveolar bone proper).
osteoblasts
T/F. Ectomesenchymal cells do not remain in mature periodontium and therefore do not participate in the turnover of this tissue.
False, they DO remain and participate in the turnover of this tissue.
The gingiva is part of the ___ mucosa which covers the ___ ___ and surrounds the ___ of the teeth.
masticatory; alveolar process; cervical
what are the three parts of the gingiva?
- free gingiva
- attached gingiva
- interdental papilla
what are three names for the free gingiva?
- gingival sulcus
- marginal gingiva
- sulcus depth
The free gingiva extends from the free gingival ___ to the free gingival ___.
margin; groove
T/F. The free gingiva is made up of non-keratinized epithelium.
False, it is made up of KERATINIZED epithelium
The free gingival margin is the ___ end of the gingiva and is located ___-___mm coronal to the CEJ.
coronal; 1.5-2mm
The free gingival groove is the junction between the free and ___ gingiva. It corresponds to the ___ but may only be found in ___-___% of adults.
attached; CEJ; 30-40%
Which part of the gingival epithelium faces the oral cavity?
the oral epithelium
Which part of the gingva faces the tooth surface without contacting it?
oral sulcular epithelium
The ___ epithelium provides the contact between the gingiva and the tooth.
junctional
The free (marginal) gingiva is limited macroscopically by which structures? microscopically?
Macro - extends from Free Gingival Margin to Free Gingival Groove
Micro - extends from Free Gingival Margin to Junctional Epithelium
Why do we care about the microscopic and macroscopic landmarks of the free (marginal) gingiva?
Because these landmarks change from health to disease and determine the accuracy of probe readings.
The attached gingiva has a ___ texture, is ___ pink and ___.
firm; coral; immobile
T/F. The width of the attached gingiva decreases with age.
False, it INCREASES with age due to passive eruption.
The attached gingiva is widest in ___ and narrowest in ___ on the buccal side of the maxilla.
incisors; premolars
The mandibular lingual width of the attached gingiva is narrowest in ___ and widests in ___.
incisors; molars
Define stippling.
Small depressions on the attached gingiva found in 40% of adults and is seen as a sign of health.
The ___ junction is the junction between attached gingiva and alveolar mucosa.
mucogingival
T/F. The mucogingival junction is found on the palate.
False, it is NOT found on the palate.
Attached and marginal gingiva are ___ (keratinized/non-keratinized).
keratinized
The significance for attached gingiva is that it supports ___ gingiva and is the base for movable elements (lips, cheek and tongue). It can withstand ___ and functional stresses because of its thick ___ ___ layer that is firmly bound to the ___ and bone.
marginal; frictional; CT; periosteum
T/F. Attached gingiva serves as a passage of inflammation.
True.
If your patient has great oral hygiene, should the thickness of the attached gingiva matter?
no
If your patient has less than optimal oral hygiene, what should you consider?
the width (height) and thickness of the attached gingiva. Both matter to prevent inflammation.
What three things does the shape of the interdental papilla depend on?
- the contact relationships between adjacent teeth
- the width of approximal tooth surfaces
- the course of CEJ
What is the col?
the concavity seen in contact areas of premolar / molar region
What type of epithelium is found in the col? What is this similar too?
non-keratinized epithelium. This is similar to junctional epithelium
What happens to non-keratinized tissue if you extract a tooth or have an open contact?
it’ll keratinize. Keratinized tissue resists infections better than nonkeratinized tissue
The oral epithelium is a ___ (keratinized/non-keratinized), ___ (simple/stratified), ___ (squamous/columnar) epithelium that contains keratin-producing cells known as ___.
keratinized; stratified; squamous; keratinocytes
What are the four layers of the oral epithelium?
- basal layer (stratum basale or germinativum)
- prickle cell layer (stratum spinosum)
- granular cell layer (stratum granulosum)
- keratinized cell layer (stratum corneum)
T/F. Cell nuclei are lacking in the outer cell layers of the oral epithelium.
True, this epithelium is called orthokeratinized.
What term is used if the cells of the stratum corneum contain remnants of the nuclei?
parakeratinized
From the basal layer to the granular layer both the number of ___ in the cytoplasm and the number of ___ increase. What decreases in number?
tonofilaments; desmosomes
organelles decrease
___ make up 90% of the cells of the oral epithelium. Clear cells include ___(synthesize melanin pigment), ___ cells (defense cells), and ___ cells (sensory).
Keratinocytes; Melanocytes; Langerhans; Merkel’s
Where are basal cells found?
present between the basal layer of the oral epithelium and CT.
T/F. The basement membrane is 1-2um wide, rich in glycoproteins and contains protein-polysaccharide complexes.
True.
What are the two layers of the basement membrane that can be seen on electron microscope?
lamina lucida and lamina densa
Which layer of the basement membrane is adjacent to basal cells? Which layer is adjacent to connective tissue?
lamina lucida - basal cells
lamina densa - CT
Anchoring fibers project from the lamina ___ into connective tissue.
densa
What are the dense plaques that attached epithelium to the basement membrane called?
hemidesmosomes
A pair of hemidesmosomes is known as ___.
desmosomes
The surface of the epithelium that faces the connective tissue has several depressions from the connective tissue ___. The epithelial ridges or ___ ___ intervene.
papillae; rete pegs
What happens when the rete pegs fuse?
stippling
What is missing from the JE sites, papillae or rete pegs?
rete pegs
