Lecture 3- Efficacy of diagnostic techniques Flashcards
What is the main limitation of probing
lack of sensitivity and reproducibility
The …. of a diagnostic test refers to the probability of the test being positive when the disease is true present
sensitivity
The… of a diagnostic test refers to the probability of the test being negative when the disease is not present
specificity
Is sensitivity for bacterial culturing high or low?
low, detection limits for selective and nonselective media average 10^4 to 10^5 bacteria
For microbiologic testing, what is the gold standard?
bacterial culturing
Bacterial culturing assesses for …. of microbes but a limitation is that you can only grow … bacteria so strict sampling and transport conditions are essential
antibiotic susceptibility
live
disadvantages of bacterial culturing
expensive
need experienced personnel
time consuming
sophisticated equipment
direct and indirect immunofluorescent microscopic assay are able to identify pathogens using a … … and it is used to detect mainly … and …
plaque smear
Aa and Pg
Does direct and indirect immunofluorescent microscopic assay require the bacterial cells to be viable?
no
which test can be used chairside to detect Aa, Pg and Pi?
Enzyme-linked immunosorbent assay (ELISA)
PCR has high …. and … for the identification of target pathogens and it has a low …. limit but is unable to quantify pathogens accurately in clinical samples
sensitivity and specificity
detection
most common source to assess host response?
gingival crevicular fluid
saliva is 2nd most common
paper strip to collect GCF is placed within crevice for …
30 seconds
GCF volume can be quantified by..
Periotron
There are currently more than … components of GCF that have been evaluated
65
host derived enzymes can be … or …
intracellular
extracellular
Intracellular destruction enzymes from the host are possible markers of…. released from dead or dying … from the periodontium
periodontal destruction
PMNs/neutrophils
What are the 4 intracellular destruction enzymes that are seen
aspartate amino-transferase
alkaline phosphatase
B-glucuronidase
Elastase
…. is released during tissue destruction
aspartate amino-transferase
… is a membrane-bound glycoprotein involved in maintenance of alveolar bone
alkaline phosphatase
… is a lysosomal enzyme that degrades proteoglycans and ground substance
B-glucuronidase
… is a proteolytic enzyme found in lysosomal granules of neutrophil
elastase
extracellular destruction enzymes are associated with the activity of …
matrix metalloproteinases
… can be detected chair side with Periogard Periodontal tissue monitors, but it is not able to discriminate bewtween sites with severe inflammation with or without attachment loss
Aspartate aminotransferase (AST)
Alkaline phosphatase (ALP) is higher in the GCF in … than … sites
diseased
healthy
… is elevated in GCF from sites with severe periodontal disease, it has a high sensitivity and specificity when related to occurence of clinical attachment loss
B-glucuronidase
… can be tested for chairside with Periocheck and it has a positive correlation (if its in GCF) with clinical attachment loss
Elastase
The ECM of the periodontium is mostly composed if … , … and ,,,
collagen
proteoglycan
non-collagen proteins
elevated levels of … can be seen in collagen breakdown
hydroxyproline
tissue … reflects increased oxygen consumption that occurs with persistent inflammation
hypoxia
