Fluoride and dental caries

Question 1

what is the ideal fluoride concentration in water and why is this the best amount of fluoride

Answer 1

1 ppm

because it maximizes caries benefit and minimizes fluorosis

Question 2

what is the general trend between fluorosis and water fluoridation

Answer 2

the higher the concentration of fluoride; the higher prevalence of fluorosis

Question 3

can you get fluorosis from topical application of fluoride?

Answer 3

no

only from ingestion

Question 4

does fluoridated water benefit the individual before tooth eruption

Answer 4

NO

teeth must erupt to get benefit from topical fluoride

Question 5

what must occur in order to have continue benefit of water fluoridation

Answer 5

must have continuous usage of water that is fluoridated throughout life

Question 6

what is the key in reducing prevalence of severe caries in the population

Answer 6

using topical products in addition to water fluoridation

ex: toothpastes

Question 7

why is water fluoridation so effective

Answer 7

frequent exposure to low concentration of fluoride (topical aspect)

Question 8

what happens during secretory stage of forming enamel and what happens with high levels of F- ion

Answer 8

ameloblasts lay down protein matrix for crystal rod structure and form rods

high levels of F- ion can cause pitting and disturbances in form

Question 9

what happens during maturation stage of forming enamel and what happens when there is high level of F- ion

Answer 9

ameloblasts fill in the rods/crystal structure with mineral

high F- ion causes disruptions in crystal formation and we see chalky white and weakness of enamel

Question 10

what is “post-eruptive enamel maturation”

Answer 10

the idea that the tooth when erupt is not completely pure

saliva and fluoride are exposed to the erupted tooth and perfects the impurities

• phosphate replaces carbonate
• calcium replaces sodium
• fluoride replaces hydroxyl

Question 11

at what pH does hydroxyapatite begin to dissolve

Answer 11

5.5

Question 12

at what pH does fluorohydroxyapatite begin to dissolve

Answer 12

4.5

Question 13

why are young teeth more susceptible to caries?

Answer 13

because when they first erupt they are not fully matured…they strength overtime that they are exposed to fluoride and saliva

Question 14

when there are F- ions what happens the the hydroxyapatite crystals when they demineralize and then remineralize? what is the new material called?

Answer 14

fluorhydroxyapatite

Question 15

why does the tooth dissolve susurface first and the outer shell of enamel stays intact

Answer 15

there is F on the surface making the surface less soluble than the inside

Question 16

what is true about the surface of white spot lesions

Answer 16

has higher concentrations of fluoride than surrounding areas

Question 17

what is the contraindication for dental care for a patient with white spots or fluorosis

Answer 17

do not want to polish

will remove that very thin layer of hard enamel that makes up the outer shell

Question 18

what is another area on the tooth that has higher concentration of F- ion levels

Answer 18

areas covered by dental plaque

Question 19

what is an area on the tooth that contains LOW levels of F- ion

Answer 19

abrasion, erosion

Question 20

what is the concentration of fluoride in toothpaste

Answer 20

1000

Question 21

what is a prescription toothpaste called and how much more fluoride concentration is there than in regular toothpaste

Answer 21

Prevident

5000x

Question 22

how do Ca F globules attach to the tooth

what type of effect do they have

Answer 22

after application of fluoride these globules rest on the tooth surface but do not stably attach

they release F- ion in low level of acidity

this is why good to not eat/drink 30 min after fluoride application

cariostatic effect

Question 23

what are 4 ways CaF globule deposition can be increased

Answer 23

1. increase exposure time
2. decrease pH
3. increase concentration of F-
4. protecting or limit rinsing or cover with varnish

Question 24

what minerals supersaturate saliva so teeth don’t dissolve

Answer 24

calcium and phosphate

Question 25

what are three pellicle proteins

what are their function

Answer 25

1. statherin
2. proline rich proteins
3. tyrosine rich proteins

protect from overgrowth of hydroxyapatite

Question 26

there are high levels of calcium and phosphate in plaque biofilm
what is one pro and one con

Answer 26

pro: helps remineralization
con: lead to calculus

Question 27

when does fluorosis occur

Answer 27

ONLY while teeth are developing

Question 28

what is the characteristic look of fluorosis

Answer 28

pits, bands, and loss of enamel in areas

brown discoloration post eruptive because of staining and browning of exposed proteins

mild white mottling (less severe manifestation)

Question 29

T/F: mild fluorosis is thought to be attractive by most people

Answer 29

TRUE

Question 30

when are central incisors at greatest risk for fluorosis

Answer 30

15-50 months

Question 31

what is the major antimicrobial effect of fluoride ion

Answer 31

inhibit enolase in glycolytic pathway so lactic acid cannot be produced

more affective at low pH

Question 32

concentration vs frequency in home applied and in office applied fluoride treatment

Answer 32

at home: low concentration high frequency

in office: high concentration low frequency

Question 33

at what concentration does fluoride have to be in order to get deposition of CaF

Answer 33

> 100ppm

Question 34

in the use of toothpaste what has more effect on caries; frequency or amount

Answer 34

frequency

Question 35

what is safe amount for preschool children of toothpaste

Answer 35

pea sized amount

Question 36

why are OTC rinses so affective when they are such a low concentration of F-

Answer 36

because it is known not to rinse after using

less concentration than toothpaste

Question 37

what is % of acidulated phosphate fluoride (APF)

Answer 37

1.23%

Question 38

what is % of NaF

Answer 38

0.9%

Question 39

does water fluoridation deposit CaF onto the tooth surface?

Answer 39

NO

Question 40

during development should we be concerned about incorporating fluoride into enamel

Answer 40

no, there is no anticaries benefit