Fluoride Flashcards
Fredrick McKay
discovered brown stain
coined term “mottled enamel”
determined water was the cause
HV Churchill
chemist
fluorine caused enamel change
used McKay’s findings
Fluoride
- latin word Fluere meaning flow
- discovered in 1886 by Henri Moissan
- atomic element #9
Absorption
GI tract –> passive diffusion, absorbed within 1 hour, less absorption when taken with milk and food
Blood Stream –> plasma is the carrier, maximum levels reached within 30 mins, normal levels are low, levels constantly fluctuating
Fluoride Distribution
- 99% of fluoride is in mineralize tisues
- crystal lattice of teeth (small amounds IN teeth, higher amounts ON teeth)
Excretion
- most excreted via kidneys in the urine
- small amounts by sweat and feces
- limited transfer from plasma to breast milk for excretion by that route
Pre-Eruptive: Mineralization Stage
- fluoride reaches fetus by way of surrounding blood plasma
- risky in that excess fluoride may lead to fluorosis - hypomineralization, stops ameloblasts; only occurs during development
- beneficial in that teeth develop more shallow grooves
Pre-Eruptive: Maturation Stage
-absorbed from surrounding tissues
Post-Eruptive
- obtained from water, dentifrice, rinses
- prevents caries
- rapid uptake during first years after eruption
- fluorosis is not possible once tooth development is complete
Dentin
- fluoride is greater in exposed dentin than in enamel
- higher concentration at pulp where exchange takes place
- newly formed dentin absorbs fluoride rapidly
Biofilm/Saliva
- may contain 5-50ppm fluoride
- fluoride remineralizes teeth by attracting calcium and phosphate
- inhibits demineralization (pH < 5.5)
Caries Diagnosis and Management
-can be sealed up to moderate lesion ICDAS 3
ICDAS 0 to ICDAS 6
Remineralization
- saliva neutralizes acids
- mineral replacement
- arrests caries
- white spots harden/hypermineralize
Norfolk
optimal fluoride level 0.90 mg/L
Topical Effects of Fluoride Preventing Caries
- inhibit demineralization
- enhance remineralization of incipient lesions
- inhibit bacterial activity by inhibiting enolase, an enzyme needed by bacteria to metabolize carbohydrates
Water Levels
- cold: 1.2ppm
- temperate: 1.0ppm
- warm: 0.7ppm
*****0.7ppm everywhere
72% of US population now has fluoridated water
Root Caries
-demineralization starts pH 6-6.7
Benefits
-increase in alveolar bone density
-less tooth loss and periodontal disease
more well controlled perio
Food
- not a good source on its own
- cooking with fluoridated water
- fluoride salt not approved in US, but used in other countries
School
- swish programs when no community water fluoride
- overcompensate 4.5x more than recommended
- EPA approved community fluoridated water content
- FDA approves fluoridated bottled water
Compounds Used to Fluoridate Water
- sodium fluoride
- sodium silicofluoride
- hydrofluorosilic acid
Fluoride in Children Chart
AGE 0.6ppm
0-6mo. none none none
6mo-3yr 0.25mg none none
3-6yr 0.5mg 0.25mg none
6-16yr 1.0mg 0.5mg none
Toothpaste
- normally contains 1000-11,000ppm fluoride
- 15-30% reduction in caries
Mouthrinse
20-35% caries reduction in children
Dentifrice Ingredients
-stannous fluoride 0.45% (1000ppm)
[first approved by ADA]
-sodium fluoride 0.24% (1100ppm)
-sodium monofluorophosphate 0.76% (1000ppm)
Prescription Guidelines
- no more than 264mg NaF (120mg Fl2)
- supplements taken with juice or water
Sodium Fluoride
-5% 22,600ppm -0.3-0.5mL/application -retained 24-48hours after application -2-4x/year -neutral pH 7 -tray method most effective for those with rampant decay
Acidulated Phosphate
- 12,300ppm
- good taste and tissue compatibility
- etches composite and porcelain
- 1.23% gel and foam
- 4min applications 1-2 times/year
Stannous Fluoride
- only available in rinse form
- 19,360ppm
- tin ion
- not used regularly
- poor taste, very unstable, stains teeth, tissue sloughing
Xylitol
- alternative to fluoride
- natural sugar found in fruits, vegetable, and trees
- our bodies produce 5-15 grams/day
- natural carb metabolized in liver
- reduces bacterial load
- decreases caries
- increases oral pH
- does not raise glycemic index
- 10g/day 5times/day
- too much can lead to diarrhea
Acute Toxicity
- quick intake of an excessive amount of fluoride
- ingesting fluoride rinses, gels, foams, toothpaste
Certainly Lethal Dose
- amount of fluoride ingested with without antidotal therapy can cause death
- symptoms begin 30mins-24hours
- adult: 5-10g of fluoride
- child: 0.5-1g of fluoride
- induce vomiting, administer milk of magnesia
Safely Tolerated DOse
- one fourth of CLD
- depends on child weight
GI
fluoride combines with HCl in stomach to make HFl causing stomach irritation
-nausea, vomiting, diarrhea, abdominal pain, increased salivary flow, thirst
