Fluoride

Question 1

What is the mode of action of fluoride?

Answer 1

Fluoride causes dissolution of hydroxyapatite and replaces it with fluorapatite which is stronger, enhancing remineralisation of initial carious defects and inhibit further demineralisation that leads to caries initiation/progression.

It slows down development of decay by stopping demineralisation, makes enamel more resistant to acid attack, speeds up remineralisation and stops bacterial metabolism to produced less acid.

Question 2

By how much can fluoride toothpaste reduce caries?

Answer 2

Primary dentition up to 37%

Permanent dentition up to 24%

Question 3

What are the fluoride toothpaste strengths?

Answer 3

First tooth to 3yrs:
- 1000ppm smear 0.1ml

4-16yrs:
- 1000-1500ppm pea size0.25ml

High risk under 10:
- 1500ppm

High risk 10-16:
- 2800ppm (0.619%)

High risk >16yrs:
- 5000ppm (1.1%)

Question 4

What is the strength of fluoride MW used? And who can be prescribed this?

Answer 4

0.05% daily or 0.2% weekly (225ppm) for over 7yr olds

Question 5

What is the strength of fluoride varnish and when should it be used?

Answer 5

Duraphat fluoride varnish 22,600ppm (5%) 3-4x yearly for over 2yr olds

0. 25ml <6yrs
1. 4ml >6yrs
2. 8mg of fluoride in duraphat

Question 6

What are the fluoride toxicity levels and management?

Answer 6

<5mg/kg - give calcium orally (milk) and observe for few hours.

5-15mg/kg - give calcium orally and admit to hospital

> 15mg/kg - admit to hospital immediately, cardiac monitoring and life support for IV calcium gluconate

Lethal dose 32-64mg/kg.

Question 7

What are the contraindications for use of fluoride varnish?

Answer 7

Colophony allergy
Hospitalised in past 3yrs with asthma attack
Fluoride varnish applied in past 24hrs

Question 8

What are the 7 elements to determine caries risk?

Answer 8

Clinical evidence
Dietary habits 
Social history 
Fluoride use
Saliva 
Plaque history 
Medical history

Question 9

What are the 8 elements of the preventative programme?

Answer 9

Radiographs 
Tooth brushing instructions 
Strength of fluoride in TP
Fluoride varnish use
Fluoride supplementation 
Dietary advice
Fissure sealants 
Sugar free medicines

Question 10

An 8yr old high risk caries rate child what should be their appropriate fluoride regimen?

Answer 10

Brush 2x daily wit 1350-1500ppm TP

Daily 0.05% NaF MW