DOH133 Lecture Notes - Lecture 9: Cementum, Endodontics, Dentin
PBL
1. How antibiotic works- lev 5 – used to treat a variety of bacterial infections.
Belongs to fluoroquinolone antibiotics. Works by stopping growth of
bacteria. Does not effect viralinfections. Used to treat bacteria infection on
skin/sinuses/kidneys/bladder/prostate. Effective against gram negatives. It
is a DNA gyrase inhibitor. Dna gyrase has an A and B subunit and
fluoroquinolones bind to the A subunit and interfere with its strand cutting
andresealing function
2. Side effects of antibiotic – cause tendon damage, diarrhea, blisters, fever,
swelling of skin, sensation of burning on skin, trembling, skin rash, mood
changes, dizziness, drowsiness
3. Why can a microbe be resistant to certain antibodies – transfer of antibiotic
resistant genes (borrowing resistant genes from neighbouring bugs) and
spontaneous mutation in the bacterium’s dna (antibiotics work by
inactivating an essential bacterial protein Genetic change can remove that
protein. Also mutations can prevent it from inactivating the target protein)
4. Microbial antagonism – when normal microbiota benefit the host by
preventing the overgrowth of harmful microorganisms
5. Whether it’s a broad or narrow spectrum (antibiotic) – whether its specific
to certain types of bacteria or has a wide range of antibiotic actions and a
lot of bacteria. Lev is broad spectrum
6. Minimum inhibitory concentration (antibiotic) – minimum amount of
antibiotic required to kill bacteria/disease/infection
7. Ecoli causes – improper food handling, food processing, contaminated
water and animals
Document Summary
Pbl: how antibiotic works- lev 5 used to treat a variety of bacterial infections. Lev is broad spectrum: minimum inhibitory concentration (antibiotic) minimum amount of antibiotic required to kill bacteria/disease/infection, ecoli causes improper food handling, food processing, contaminated water and animals. Detail is poor and no soft tissue can be identified. Time consuming, expensive and detail is limited by section thickness: decalcified section. To produce a thin section of tooth that can be examined with transmitted light it is necessary to first decalcify the tooth to remove the mineral component of enamel, dentine and cementum. This technique has the advantage that thin, stained sections of tooth can be examined, but enamel is lost because of its high mineral content: scanning electron microscopy. Widely used method of examining teeth and dental hard tissues (+/- restorative and endodontic materials). Provides 3d images and at a large magnification range (2-3x to thousands of times): transmission electron microscopy.
