Periodontium I Flashcards
What is the periodontium?
What 3 structures make it up?
Tissues that invest and support the tooth
- Alveolar process
- Cementum
- PDL
When does the periodontium develop?
Series of complex interactions of mesenchymal, HERS, and dental follicle
What are the gomphoses?
Fibrous peg-in-socket joint
What is the fx of teeth?
Survive cycling loading over time
What are the origins of the periodontium?
Osteoblasts - Surrounding mesenchymal (NOT ECTOMESENCHYME) tissues
Cementoblasts - HERS/follicle cells - Ectomesenchymal cells
PDL fibroblasts - Follicle cells/ectomesenchymal cells
Odontoblasts - Form dentin part of the cemento-dental junction, dental papilla
T/F - The periodontium contains 3 out of the 4 types of mineralized tissues found in the oral cavity.
TRUE
Bone, dentin, cementum
—NOT ENAMEL
What is avulsion?
Traumatic removal of teeth
The alveolar process is formed by what?
Intramembranous ossification
-Mesenchyme direct to bone - NO CARTILAGE INTERMEDIATE
When does the alveolar process form?
8th week of uterine life
- Tooth germs contained in horseshoe-shaped grooves of the mandible and maxilla
- Crypts develop around tooth germs, such that they eventually form the sockets
T/F - The alveolar process develops substantially during tooth eruption, under the influence of the dental follicle.
TRUE
-Remodeled thru-out life
What is an anodontic individual?
Alveolar process development impaired
What are the differences b/t alveolar bone proper and supporting alveolar bone?
Alveolar bone proper (right around tooth)
-Compact bone
—Cribiform plate, lamina dura
Supporting alveolar bone (supports the compact bone around the tooth)
-Compact and trabecular bone
—Compact: Cortical plates
—Trabecular: Central spongiosa
What are the 3 parts of the alveolar bone proper and describe them?
Cribriform plate - Volkmann’s canals running thru it
Lamina dura - Area of PDL attachment
Bundle bone - Sharpey’s fibers (PDL) embedded in bone
T/F - W/o the dental follicle, a tooth will NOT erupt.
TRUE
Tell me about the inner part of the alveolar bone proper.
Remodeling rate my be high due to constant adaptation to tooth movements
—Consists of woven bone, but some lamellar bone is present
—Smooth surface in young individuals, but comes rougher with age
Tell me about the outer portion of the alveolar bone proper.
Lamellar bone, continuous with supporting alveolar bone
Tell me about the cortical plate of the supporting alveolar bone.
Inner - Lingual and palatal surface
Outer - Labial and buccal surface
What is the alveolar crest?
Junction of cortical plate and alveolar bone proper
-Thinner in maxilla, thicker in premolars and molar region of mandible