Lecture 2 questions Flashcards
What does the shape of interdental papilla depend on?
the contact relationships between adjacent teeth, m width of approximate tooth surfaces, course of CEJ
what is the col region?
concave, non-keratinized epithelium on the contact of 2 teeth, created susceptibility for perio disease, best to check for it in molar area. we have to wedge b/c any crap left behind while operating can cause perio disease
What is the golden rule?
the papilla is complete when it reaches 5 mm from the crest of the bone
When does supra eruption happen?
with older age 40+
What is the oral epithelium?
keratinized, stratified, squamous epithelium
What are the 4 layers of the oral epithelium?
basal (stratum basale), prickle (stratum spinosum), granular (stratum granulosum), and keratinized cell layer (stratum corneum).
Are there blood vessels in epithelium?
no
what do desmosomes in the basal layer do?
diffuse nutrients
Which layer of the oral epithelium is the only one capable of replication or division?
stratum basale
What are the cells in the oral epithelium?
keratinocytes (90%), melanocyes, langerhans (defense), and Merkel (sensory)
Where is the basement membrane and what does it contain?
located between basal layer and CT and contains glycoproteins (that collect fluid for hydration) and protein-polysaccharide complexes
What are the layers of the basement membrane?
lamina lucida (adjacent to basal cells) and lamina densa (adjacent to CT). There are anchoring collagen fibers projecting from LD into CT
What are hemidesmosomes?
dense plaques that attach the epithelium to the basement membrane
When epithelial ridges/rete pegs fuse in oral epithelium and CT, what is seen?
stippling, which is usually seen in thick biotype
Where does junctional epithelium come from?
- during tooth eruption: from reduced dental epithelium
- after tooth eruption: cells of OR differentiate into cells of JE where it has faster turnover and regeneration than OE
Where is the JE widest and thinnest?
widest in coronal and thinnest toward CEJ
differences between JE and OE?
- size of the cells: JE>OE (b/c JE is metabolically active)
- size of intercellular space: JE>OE (bc theres a lot of diffusion we need a lot of neutrophils to come out in this space and clean plaque, etc on teeth)
- number of desmosomes: JE
Where is necrosis of JE seen?
- necrotizing ulcerative periodontitis (bone is exposed)
What are the cells in the lamina propria?
- fibroblast (make matrix and fibers)
- mast cells (vasoactive substances)
- macrophages (phagocytosis and synthesis)
- neutrophilic granulocytes
- lymphocytes
- plasma cells
What are the fibers in lamina propria?
collagen (most abundant), reticulin (BM and around vessels), oxytalan (in PDL), elastic (around vessels)
What do gingival fibers do?
- reinforce gingiva, provide resilience and tone, maintain architectural form and integrity
What are the types of gingival fibers?
circular (only ones not connected to cementum), dentogingival, dentoperiosteal, transseptal
What are the types of the PDL fibers?
alveolar crest fibers, horizontal fibers, oblique fibers, apical fibers
What are the cells of the PDL?
fibroblasts, osteoblasts, osteoclasts, cementoblasts, epi cells, nerve fibers, epithelium cell rests of Mallassez, remnants of HERS
