Lecture 17

Question 1

naturally occurring mineral form of calcium phosphate {Ca5(PO4)3(OH) or stoichiometricCa10(PO4)6(OH)2}. One hydroxyl group can be substituted by carbonate, fluoride, or chloride; is the form of mineral which is found in bone and teeth

Answer 1

Hydroxyapatite

Question 2

the delivery of calcium and phosphate, from outside the tooth, into the enamel lesion, the presence of fluoride favors deposition of mineral onto the demineralized enamel surface

Answer 2

Remineralization

Question 3

involved in transporting many sugars into bacteria; sugars can differ between bacterial groups, mirroring the most suitable carbon sources available in the environment

Answer 3

phosphotransferase system (PTS)

Question 4

T/F: The stronger the acid, the more rapidly caries breaks down material

Answer 4

True

Question 5

refers to the dissolution of tooth enamel and dentin. It starts in the pits, fissure, and interdentinal regions of the teeth, “stagnation areas” from which bacteria are difficult to remove. The extent of caries is measured as the number of teeth diagnosed as decayed, missing, or filled due to caries-DMFT (Levine)

Answer 5

Caries

Question 6

a group of microorganisms in which cells stick to each other on a surface. Adherent cells may be embedded within a self-produced matrix of polymeric extracellular substance or slime which also includes DNA, proteins and polysaccharides. Cells within a biofilm can exhibit special phenotypic and symbiotic characteristics

Answer 6

Biofilm

Question 7

developmental problem also termed mottling of teeth which is caused by exposure to excessive concentrations of fluoride (>1ppm)

Answer 7

Fluorosis

Question 8

enamel formation

Answer 8

amelogenesis

Question 9

Sources of bacterial lactic acid

Answer 9

Fructose from sucrose, salivary amylase, other bacteria

Question 10

Production of bicarbonate from carbon dioxide is catalyzed by _______ which is present in saliva and salivary glands

Answer 10

carbonic anhydrase enzyme

Question 11

96% calcium hydroxyapatite crystals; 4% organic materials and water; most highly mineralized tissue in the body; can’t be produced post-natally

Answer 11

Enamel

Question 12

product of odontoblasts and ameloblasts and it bridges these two dissimilar mineral phases; acts as a barrier; must be penetrated in order for decay to progress to the dentin and ultimately to the pulpal chamber.

Answer 12

DEJ

Question 13

T/F: Caries is an infectious bacterial disease that does not show heritability

Answer 13

False; shows heritability

Question 14

antibiotic peptide produced by Strep. Mutans. Class of compounds called lantibiotics

Answer 14

Mutacin

Question 15

T/F: Hydroxyapatite is insoluble in acid

Answer 15

False

Question 16

resistant to digestion with bacterial enzymes dextranase and fructanase

Answer 16

structure of mutans

Question 17

benefit of transforming glucose to glucose-6P is

Answer 17

it won’t leak out of cell providing one way concentration of glucose

Question 18

do not metabolize glucose for energy source but use protein and amino acids instead. These bacteria contribute to the ability of advanced caries to degrade dentin collagen matrix and expand the cavity

Answer 18

Asaccharolytic bacteria

Question 19

attaches bacteria to teeth surfaces; following a carb-rich meal, it digests these carbs to maltose, which is transported into the cytosol similar to fructose-6-phosphate and then metabolized to lactic acid

Answer 19

salivary amylase

Question 20

region of pus within teeth or gums usually initiated as a bacterial infection

Answer 20

Dental Abscess

Question 21

properties and effects on mineralized tissues like teeth

Answer 21

fluoride

Question 22

Does caries occur more commonly with high carb diet or protein?

Answer 22

carb

Question 23

can bind to teeth surfaces via salivary proteins in the absence of sucrose; can make glucans and fructans which enhance adherence of Strep. mutans and acid production

Answer 23

Actinomyces spp. and viridans species of streptococci

Question 24

typically occurs when bacteria from another part of your body, such as your mouth, spread through your bloodstream and attach to damaged areas in your heart. Left untreated can damage or destroy your heart valves and can lead to life-threatening complications. Treatments include antibiotics and, in severe cases, surgery; is uncommon in people with healthy hearts. People at greatest risk have a damaged heart valve, an artificial heart valve or other heart defects

Answer 24

Endocarditis

Question 25

is a distinct method used by bacteria for sugar uptake which uses phosphoenolpyruvate as an energy and phosphate source

Answer 25

PEP group translocation (phosphotransferase system or PTS)

Question 26

formed after tooth formed as a layer on the root bordering pulp tissue

Answer 26

Secondary dentin

Question 27

hydroxyapatite with a hydroxyl group substituted by fluoride atom. Because fluoride is more electronegative than hydroxyl group, it replaces the latter in the hydroxyapatite crystal structure without altering the overall structure, called an isomorphous replacement

Answer 27

Fluoroapatite

Question 28

_____ interactions mediate cell-pellicle and cell-cell interactions in the oral cavity

Answer 28

carb

Question 29

______ kills bacteria by inhibiting cell wall synthesis

Answer 29

pennicillin

Question 30

created in response to stimulus like caries or wear

Answer 30

Tertiary dentin

Question 31

transported as fructose-6P where it is phosphorylated to fructose- 1,6-biphosphate and metabolized to lactic acid by glycolysis; lactic acid is excreted but trapped at the tooth surface by the glucan capsule

Answer 31

fructose (from sucrose)

Question 32

distinct method used by bacteria for sugar uptake which uses phosphoenolpyruvate as an energy and phosphate source; multicomponent system always involves enzymes of the plasma membrane and those in the cytoplasm

Answer 32

phosphotransferase system (PTS) or PEP group translocation

Question 33

inhibition of demineralization, enhancement of remineralization, inhibition of bacterial enolase activity inhibiting lactase production from ingested carbs

Answer 33

fluoride protection against caries

Question 34

The _____ and ______ of teeth also affect saliva access and thus indirectly affect development of caries, e.g., orthodontic treatment.

Answer 34

shape and spacing

Question 35

mineral phase of bones and teeth

Answer 35

carbonated hydroxyapatite

Question 36

DMFT is

Answer 36

decayed, missing, and filled teeth

Question 37

fluoride may become ineffective below a pH of

Answer 37

4.5

Question 38

porphyromonas gingivalis is cause of

Answer 38

perio disease

Question 39

As the region becomes more acidic, the developing cavity promotes greater colonization by S. mutans and even more acid resistant bacteria, e.g., Lactobacillus ssp.; The latter expand the cavity deeper into dentin; Asaccharolytic bacteria of the oral microbiota induce inflammation and abcesses within the pulp and periapical regions of a tooth affected with untreated late stage dental caries: are developments during

Answer 39

advanced caries

Question 40

production/ formation of enamel

Answer 40

amelogensis

Question 41

45% hydroxyapatite crystals•33% organic material(collagen, etc)•22% water; can be produced post-natally

Answer 41

Dentin

Question 42

related to consumption of high carb diet which are metabolized by plaque, generating lactic acid due to fermentation which demineralizes enamel and exposes underlying dentin

Answer 42

Caries

Question 43

Saliva flow over the teeth and its _____ content are a major resistance towards caries

Answer 43

bicarbonate

Question 44

differences in the gram-positive composition of supragingival microbial biofilms, dietary carb ingestion, saliva access to teeth surfaces and its flow rate, fluoride in the drinking water and toothpastes, antibodies to Strep mutans in blood and the oral cavity

Answer 44

factors determining dental caries severity

Question 45

Bacterial components of dental plaque cause dental caries

Answer 45

Strep. mutans, Strep sobrinus, and lactobacilli

Question 46

dental caries usually affects the ______ and _______ of posterior teeth

Answer 46

pits and fissures

Question 47

ameloblasts form individual _______ via their tome's process

Answer 47

enamel rods