Dental Health and Fluoride Quiz

Fluoride

• Fluoride is a salt of hydrofluoric acid
• Naturally occurring and mined globally
• Forms dry compounds (e.g., sodium fluoride, sodium silicofluoride) and liquid solutions (e.g., hydrofluorosilicic acid)
• Delivered topically (to the teeth) or systemically (through the circulatory system)

History of Fluoride

• Dr. Frederick S. McKay (early 20th century dentist) observed brown staining in Colorado Springs and associated it with mottled enamel and fewer cavities
• H.V. Churchill (chemist) identified Fluorine as the problem around 1931
• Dr. H. Trendley Dean (1930s) directed US Public Health Service research
• Optimal fluoride level for prevention: 1 ppm
• Communities began fluoridating water supplies in 1945

Fluoride & Tooth Development

• Pre-Eruptive Stage (Mineralization):
  • Primary teeth mineralization starts in the womb
  • Permanent teeth (first molars) begin mineralization at birth
  • Fluoride reaches developing teeth via the circulatory system
  • Hydroxyapatite crystals become fluorapatite in the presence of fluoride
  • Fluoride contributes to creating shallow occlusal grooves
  • Excessive fluoride during development can result in fluorosis
• Pre-Eruptive Stage (Maturation):
  • Mineralization is complete before eruption
  • Fluoride deposition continues on the enamel surface
• Post-Eruptive:
  • Fluoride uptake on enamel surface is rapid after tooth eruption
  • Uptake continues throughout life, from exposure sources like drinking water
  • Drinking fluoridated water is a continuous topical source

Fluorosis

• Fluoride exposure above 2 ppm during tooth development can disrupt enamel formation (by ameloblasts), leading to hypomineralization.
• This is associated with excessive fluoride in drinking water.

Fluoridation

• Adjusting the fluoride content of a water supply to the optimal concentration
• Cost-effective for large communities (over 20,000 people)
• Methods exist to remove excess fluoride in high concentration areas

Absorption

• Less fluoride is absorbed when taken with milk or food
• Unabsorbed fluoride in the stomach is absorbed in the small intestines
• Maximum blood stream levels are reached within 30 minutes of intake.
• Concentration in saliva: 0.01-0.04 ppm

Distribution & Retention

• Fluoride has a strong affinity for calcified tissues
• 99% of body fluoride is stored in mineralized tissues (e.g., teeth)
• Fluoride content in fully matured teeth can change due to cavities, erosion, or abrasion

Excretion

• Kidneys are the primary route for fluoride excretion in urine
• Limited amount of fluoride is transferred to breast milk for excretion

Topical Effects of Fluoride

• Inhibits demineralization
• Enhances remineralization
• Inhibits bacterial activity (inhibits enolase, an enzyme that bacteria use to metabolize carbohydrates)
• Fluoride is a natural component of enamel
• Fluoride concentration is higher in dentin
• Fluoride concentration in cementum increases with exposure

Demineralization

• Loss of calcium and phosphorus from tooth structure, primarily due to acids produced by bacteria metabolizing fermentable carbohydrates

Remineralization

• Saliva neutralizes acids
• Calcium and phosphorous are returned to tooth enamel
• Fluoride enhances the exchange of minerals between the biofilm and enamel crystals
• Fluorapatite (formed from Fluoride and Hydroxyapatite) is less soluble than hydroxyapatite

Water Fluoridation

• Studies show that water fluoridation alone reduces caries by up to 27% in adults.
• Fluoridation from birth reduces primary tooth caries by up to 40%.
• Continuous use from birth provides maximum benefits

Food Sources

• Meat, eggs, vegetables, cereals, and fruits contain small amounts of fluoride.
• Tea and fish contain higher amounts
• Fluoridated salt is available in Europe
• Bottled water and processed beverages may not provide optimal fluoride amounts
• Food cooked in fluoridated water retains more fluoride

Halo/Diffusion Effect

• Increased fluoride intake in non-fluoridated communities due to diffusion/transport from neighboring areas.

Other Water Sources

• Well water fluoride content varies depending on the source
• Reverse osmosis and distillation remove fluoride
• Carbon filters can remove varying amounts of fluoride
• Water softeners do not remove fluoride

Infant Formula

• Ready-to-feed formulas do not require reconstitution
• Water is added to powdered and liquid concentrate formulas
• Breast milk contains about 0.02 ppm fluoride; infant formulas contain 0.11–0.57 ppm

Dietary Fluoride Supplements

• Used to compensate for insufficient fluoride in drinking water (if below 0.6 ppm)
• Recommended for ages 6-16 and high-risk individuals for cavities
• Available as drops, lozenges, and tablets
• Prescribed individually

Fluoride Supplements Dose Schedule

• Dosage based on child's age and water fluoride concentration
• Table presents different dosage amounts for various situations.

Fluoride Supplements

• Available as tablets, lozenges, and drops, with dosages ranging from 0.25 mg to 1 mg.
• Consumption guidance: tablets are chewed, swished, and forced between teeth before swallowing; lozenges are dissolved in the mouth; drops are for children who cannot use tablets or lozenges

Prescription Guidelines

• Maximum dispensing amount per household: 264 mg NaF (120 mg fluoride ion)
• Take with food to reduce stomach upset
• Avoid with dairy products due to reduced absorption.
• Prenatal supplements not recommended for caries prevention (weak evidence)

Professionally Applied Topical Fluorides

• Various fluoride forms (e.g., neutral NaF, acidulated phosphate fluoride) and concentrations (e.g., 2%, 5%) applied professionally
• Application methods (e.g., tray application), frequencies, and additional details regarding procedures are outlined in the given text.

Professional Topical Applications

• 2.0% NaF: Neutral Sodium Fluoride (used with esthetic restorations, contains 9,050 ppm of fluoride ion)
  • 4-minute application, neutral pH(7.0), available in foam or gel
• 1.23% APF (Acidulated Phosphate Fluoride): (containing ortho-phosphoric acid at 3.5 pH, enhancing uptake of fluoride)
  • 1 minute foam/gel were marketed; newer/updated evidence supports 4-minute tray application.

Fluoride Varnish

• 5% NaF Fluoride:
  • High concentration (22,600 ppm)
  • Low-use amount, applied once to pit/fissure and/or proximal surfaces, remains on tooth surface for several hours.
  • Reduces demineralization of white lesions
• 1994 FDA-approved for use on cavities and desensitizing agents
• Can be applied at age 1

2018 ADA Recommendations

• Use to arrest or reverse non-cavitated caries
• Sealants, APF gels (.02% NaF mouth rinse) and 5% NaF Varnish for various uses.

Application of FI Varnish

• Applying varnish to dry teeth
• Application on buccal surfaces
• Avoiding food and drinks for 30 minutes after application
• Avoiding brushing and rough food for 4 hours after application

38% Silver Diamine Fluoride

• Use in high-risk caries patients, antimicrobial effects due to 24.4%-28.8% Silver component
• FDA approved desensitizing agent with "off-label" use in caries arrest
• 2 applications per year
• State guidelines determine qualified applicators

Indications & Advantages of SDF

• Extreme caries risks (e.g., xerostomia, early childhood caries, cancer treatment)
• Patient difficulty with dental care
• No access to dental care (underserved populations)
• Non-invasive procedure (no needle/drill)

Contraindications of SDF

• Allergy to silver
• Pregnant/breastfeeding patient
• Relative contraindications (ulcerative gingivitis, stomatitis)
• Teeth with pupal involvement

Limitations & Risks of SDF

• Communication and consent are crucial prior to application
• SDF placement does not eliminate the need for future restorations
• Requires multiple visits for maximum benefit
• Permanent staining of decay area, but not healthy enamel
• Can stain skin or gingiva (dissipates within 1-3 weeks)

Self-Applied Fluoride Mouth Rinses

• Available in both prescription and over-the-counter potency levels
• Not recommended for children under 6 years
• Suitable for high-risk patients (e.g., xerostomia, radiation therapy)

Self-Applied Fluorides

• Options (prescription/OTC) include toothbrushing and rinsing, custom trays/disposables, delivering varying amounts of fluoride.
• Suitable for patients with certain conditions (like hypersensitivity).

Fluoride Dentifrice

• Consist of Sodium Fluoride (NaF) in various concentrations, plus Stannous Fluoride (SnF₂) and Sodium Monofluorophosphate (Na₂PO₃F) compounds.
• ADA seal of acceptance
• Amounts of dentifrice vary with age
• ADA's guideline for amount of fluoride for usage depends on the age of the patient.

Lethal & Safe Doses of Fl

• Adult certainly lethal dose (CLD) >5-10g
• Adult safely tolerated dose (STD) = ¼ CLD (1.25-2.5g)
• Dosage outlined in terms of fluoride /body weight

Signs & Symptoms of Acute Toxic Dose

• Symptoms onset within 30 minutes of ingestion.
• GI tract symptoms (nausea, vomiting, diarrhea, abdominal pain, increased salivation, thirst)
• Systemic symptoms (blood calcium bound by circulating fluoride, leading to hypocalcemia, CNS convulsions, cardiovascular and respiratory depression).

Chronic Toxicity

• Skeletal fluorosis can result from long-term high fluoride exposure (>10 years from 8-10 ppm).
• Severe dental fluorosis (≥2ppm) vs mild fluorosis (white spots)

Emergency Treatment

• Induce vomiting via digital stimulation, call EMS
• If vomiting is not effective, administer fluoride-binding liquids (e.g., milk, milk of magnesia, calcium hydroxide)
• Immediate support of respiration and circulation

Documentation

• Always gather permission for fluoride treatment
• Document details like treatment type, concentration, and method of delivery (application)

Test your knowledge on the role of fluoride in dental health and its impact on teeth. This quiz covers fluoride sources, its effects on enamel, and public health recommendations regarding fluoride usage. Ideal for students and professionals in dentistry and health fields.