Role of F Flashcards
3 levels of prevention action in public health
Upstream – population level
- Government, public health policies
Community
- Schools
Downstream – individual
- Clinician for pt
F therapy settings
- community
- clinic
- home
community F therapy e.g.
- water
- school based brushing
- varnish in nurseries
- Salt
- Milk
- Tablets
- Rinsing
clinic F therapy e.g.
- Varnish
- Gels and foams
- Slow release
home F therapy e.g.
- Toothpaste
- Mouthrinse
- Tablets
silver diamine fluoride SDF
- Vehicle for Fluoride
- Used in populations with poor access to services to help prevent the spread of active carious lesions
how does Fluoride prevent caries
- Fluoride present in fluid at the plaque/tooth interface promotes remineralisation
- The Fluoro-Apatite formed is less susceptible to demineralisation
- Topical effect greater than systemic effect
- Fluoride may also have an effect on bacteria and metabolic pathways resulting in less acid being produced
- Maintain elevated oral levels of fluoride for as long as possible (little and often)
- Fluoride most effective on early lesions
oral reservoirs for F
- Oral reservoir is small
- Fluoride from toothbrushing disappears quickly
- Oral reservoirs 2 broad types:
- Mineral deposits (CaF2; FAP) calcium fluoride and fluoroapatite
- CaF2 in saliva and fluid phase of plaque
- Biologically/bacterially bound calcium-fluoride
- Mineral deposits (CaF2; FAP) calcium fluoride and fluoroapatite
- Aim is to maintain cariostatic levels of F in oral fluids
- ?Fluoride boosting?
- Often a key goal for manufacturers of dental products
systemic Vs topical
F debate
- Generally agreed that main effect is topical
- Water fluoridation is effective as universal and passive
- Dentifrice use should be encouraged and should be optimised through simple advice and education
- Public health vs. personal interventions
methods of delivering F in oral care products
- Toothpaste
- Mouth rinse
- Varnishes and gels
- Tablets
Don’t forget other vehicles for fluoride (SDF)
water fluoridation
- Community water supply fluoride content adjusted (0.8 – 1.0ppm)
- Early 20th Century – effect of fluoride on caries
- Dean et al, Grand Rapids (USA) 1950s
- Common in USA, Repbulic of Ireland, areas of England
- Scotland – not currently
- What is the future for water fluoridation?
- Improving the evidence base, CATFISH (challenge to overcome to gain public support)
If fluoride action is topical, is water fluoridation relevant? Adjust water, water ingested, becomes incorporated into saliva thus contain low and frequent level of F
F tablets
Clinical trials
Systemic method of delivery
- Reductions.
- 50% deciduous dentition.
- 30% permanent dentition.
Many studies of flawed design.
- Best outcomes result from.
- `swish and swallow’ procedure.
- Teeth already erupted
UK Guidelines - Not a Public Health Measure
- May be applicable to high risk children
Poor risk-benefit balance – not recommended
Compliance issues
F tablets dose
- 6m-3yr 0.25 mgF
- 3-6 yrs 0.5 mgF
- >6yrs 1.0 mgF
disadvantages of F tablets
- Poor risk-benefit balance – not recommended
- Compliance issues
F mouthrinse
- Commonly available for home use as:
- Daily (0.05% 227ppmF)
- Weekly (0.2% 909ppmF)
- Reductions in caries of around 30%
- Daily rinsing slightly more effective than weekly rinsing, but more expensive
- Weekly more cost effective than daily
- Swishing round mouth important for efficacy
- Good benefit to risk ratio
- Generally good compliance
BUT
- Cost benefit ratio is low
F varnish - Duraphat
- High fluoride concentration
- Sodium Fluoride 50 mg/ml = 22 600 ppm F- to tooth surface
- Sustained contact
- Varnish form
- Professionally applied
- Skill mix
- DCPs dental care professionals
how does F varnish work
- Colophony resin hardens in contact with saliva to maintain contact of fluoride with the tooth
- Formation of globules of calcium fluoride
how does calcium fluoride work
acid attack
- release of fluoride ions
reminerlisation
- increase F on surface so drive reminerlisation
Fluoride booster
- Casein Phosphopeptide – Amorphous Calcium Phosphate (CPP-ACP)
- not suitable for those with milk allergies - casein
- Used to be adjunct to F but now supplied with F
- Can be used at home or in office in trays
- Useful in markets with no access to high fluorides
- Systematic reviews indicate more research needed
effect of F on tooth surface
- Presence of F during caries process alters demin/remin dynamics
- Partially demineralised crystals
- act as nucleators
- F ions adsorbed to crystal surface
- Attract Ca, P – new mineral formed
- FAP “veneer” (FAP + HAP), lower solubility fluorapatite
principle mechanism of F in caries control relies upon (3)
- Flouride in saliva
- Fluoride at plaque fluid and tooth interface
- Fluoride in fluids around lesion mineral crystals
F in caries control in optimised by
- Delivery of fluoride to tooth surface, plaque and plaque fluid
- Remember the size of the oral reservoir and ‘fluoride boosting’
- Maintaining fluoride levels (frequency of exposure)
F concentration in toothpaste impact
- 6-7 percent reduction in caries for every 500 ppm F increase in fluoride concentration
Use of low fluoride formulations provide less anticaries benefit.
- Choice of toothpaste depends on careful risk benefit assessment
F toothpaste frequency of application impact
More frequent brushing results in lower caries increments
rinsing behaviour impact on F toothpaste effect
spit don’t rinse effective
No beaker – less water in, smaller caries increment than larger volume of water
does amount of toothpaste effect efficacy
quantity of toothpaste applied is not strongly associated with efficacy
need suitable amount for age to reduce toxicity risk
F use pros and cons
- Efficacy of fluoridated toothpaste clearly demonstrated.
- Higher fluoride content, more caries prevention
BUT…
- Despite being topical – inevitable ingestion, particularly in young
- Increased risk of enamel fluorosis
- Risk – Benefit assessment between caries prevention and fluorosis risk
amount of F ingested to cause fluorisis in children
General consensus ~ 0.1 mg f/kg body weight
- 1 mg per day for 1 year-old
- 2 mg per day for 5-6 year-old
There is no lower limit below which fluorosis does not occur!
There appears to be a dose response between fluoride exposure and fluorosis severity
graph shows not a lot of daily quantity of stronger toothpastes need ingested to reach toxicity levels
does concentration or quantity impact risk of fluorsis
Large smear of toothpaste as a much greater risk of fluorosis then changing concentration of toothpaste
Therefore, safer to use a small quantity of high concentration toothpaste for efficacy and reduce risk of fluorosis
