ICP L8: Caries prevention - Fluoride, diet and saliva

Question 1

NaF

Answer 1

Most common source of fluoride

Question 2

Na2PO3F

Answer 2

Industrial form of fluoride

Question 3

Why do NaF and Na2PO3F have similar properties

Answer 3

Because of the presence of alkaline phosphatase

Question 4

What does fluoride in blood, tissues and saliva+crevicular fluid lead to

Answer 4

Blood = enamel deposition and calcification 
Tissues = enamel maturation 
Saliva+CF = eruption into oral environment

Question 5

What are the 7 fluoride therapies

Answer 5

1. Water fluoridation = easy, 1ppm, low cost
2. Drops and tables = requires motivation
3. Milk = 2.5-7ppm
4. Salt = cheap, not possible where water fluoridation
5. Topical fluoride = gels, solution, varnishes professionally
6. Rinsing solutions = 0.2% 4 nights, 0.05% daily
7. Toothpastes

Question 6

What are the components of toothpaste

Answer 6

• abrasives
• detergents
• humectants
• binding agents
• preservatives
• active agents = fluoride (monofluorophosphate), anticalculus, desensitising, antibacterials

Question 7

How should fluoride toothpaste be administered

Answer 7

1. Children < 3 use a smear of 1000ppm
2. Children high caries risk use 1350-1500ppm
3. Children 3-6 use a pea of 1350-1500ppm
4. > 10 with active caries prescribe 2800ppm
5. > 8 and high risk use NaF 0.05% mouthwash
6. adults + >16 with active caries use 5000ppm max

Question 8

What is the benefit of fluoridated toothpaste

Answer 8

Loosely bound CaF2 forms on the tooth surface acting as a F- reservoir for when the pH drops to 4-5 and so provides low concentration of fluoride at the tooth surface

Question 9

Which component of toothpaste acts as an anti calculus agent

Answer 9

Sodium phosphate

Question 10

Which component of toothpaste acts as a desensitising agent

Answer 10

Strontium, potassium chloride, formaldehyde

Question 11

Which component of toothpaste acts as an antibacterial

Answer 11

Tridosen

Question 12

How is fluoride deposited in enamel

Answer 12

• during initial precipitation and growth of appetite crystals
• by reaction with surface enamel appetite in relation to dissolution and reprecipitation of appetite crystals

Question 13

What are the pre-eruptive effects of fluoride

Answer 13

1. Improves crystallinity
2. Increases crystal size
3. Decreases acid solubility
4. More rounded cusps
5. Improves fissure pattern

Question 14

What are the post-eruptive effects of fluoride

Answer 14

1. Inhibits demineralisation as the crystal sizes are larger and so less soluble
2. Promotes remineralisation of early caries
3. Increases degree of remineralisation
4. Increases speed of remineralisation
5. Increases glycolysis in cariogenic. bacteria thus decreasing the acid production in plaque
6. Inhibits synthesis of extracellular bacteria

Question 15

How is fluoride metabolised

Answer 15

• absorbed in stomach
• excreted in the kidney
• found in saliva, breast milk and placenta in small amounts

Question 16

Outline the toxic effects of fluoride

Answer 16

1. Tooth mottling on increased fluoride
2. Abscess formation around roots and decreased enamel development
3. Fluorosis
4. Chronic toxicity causing exostoses (bony growth on surface of long bones causing joint stiffness and pains)
5. Acute toxicity; poisoning, nausea, epigastric pain, decreased BP and pulse + respiration causing unconsciousness

Question 17

What is fluorosis

Answer 17

• the effect of XS fluoride intake characterised by mottling teeth
• major effect at maturation (proline-rich material remains and mineralisation doesn’t increase)
• localised increase in porosity
• may take up stain
• often superficial and lost through normal attrition
• but can affect whole thickness of tooth