Fluoride and Tooth Surface

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Questions and Answers

Who was the first to document the appearance of the Colorado stain?

Churchill

Dr Frederik McKay (correct)

GV Black

Dr H Trendley-Dean

What did Churchill investigate regarding the mottling effect on teeth?

The impact of local mining activities

The water source changes (correct)

Dental hygiene practices

Local dietary habits

What was McKay's suggestion about the correlation between mottling and dental caries?

There is no correlation between mottling and decay.

Fluoride causes mottling and increases decay.

Mottled teeth are more prone to decay.

Mottled teeth have a lower chance of decay. (correct)

Which report did not specifically address fluoride and its effects?

Cochrane review Signup and view all the answers

What was the primary focus of Dr H Trendley-Dean's research?

Links between fluoride, mottling, and caries reduction Signup and view all the answers

What did Churchill find about fluoride content in water related to mottling?

Higher fluoride was found in water where mottling occurred. Signup and view all the answers

When were the shoe leather studies conducted?

1930-1940 Signup and view all the answers

What type of fluoride is absorbed during the systemic stage of tooth development?

Fluoroapetite Signup and view all the answers

Which process is primarily enhanced by fluoride during caries prevention?

Mineralization Signup and view all the answers

What potential issue can excess fluoride during enamel development cause?

Fluorosis Signup and view all the answers

At which stage is fluoride deposition from surrounding tissue fluids most crucial?

Post-eruptive stage Signup and view all the answers

What role does the blood play in fluoride absorption during tooth development?

It carries fluoride to developing tooth buds. Signup and view all the answers

What property does fluoroapetite confer onto the tooth structure?

Greater resistance to demineralization Signup and view all the answers

Which statement about fluoride's effect on ameloblast activity is true?

Excess fluoride inhibits ameloblast activity. Signup and view all the answers

What is a primary reason fluoride is advocated in caries prevention?

It helps in enamel remineralization. Signup and view all the answers

Which fluoride absorption stage occurs after calcification but prior to tooth eruption?

Maturation stage Signup and view all the answers

What effect does fluoride have on the wettability of enamel?

It decreases the wettability of enamel. Signup and view all the answers

How does fluoride contribute to the prevention of plaque accumulation?

By reducing pellicle formation on the tooth surface. Signup and view all the answers

Which of the following effects on tooth morphology is associated with systemic fluoride?

Shallower pits and reduced fissure depth. Signup and view all the answers

Root caries is more common in which of the following patient groups?

Patients with xerostomia or limited saliva. Signup and view all the answers

What are the mechanisms by which fluoride helps prevent root caries?

Incorporating into surface during remineralisation and reducing surface wettability. Signup and view all the answers

What causes a drop in pH in the post-eruptive stage of teeth?

Bacterial acid production Signup and view all the answers

During the post-eruptive stage, what is primarily lost from the tooth surface?

Calcium and phosphate Signup and view all the answers

What process leads to the formation of fluoroapatite in teeth?

Absorption of calcium, phosphate, and fluoride Signup and view all the answers

Why is fluoride more effectively absorbed during the first 2-3 years post-eruption?

Enamel is more porous Signup and view all the answers

What happens when fluoride is applied topically to teeth?

It reacts strongly with calcium Signup and view all the answers

What is a key reason for using fluoride in caries management?

To reduce caries progression Signup and view all the answers

What effect does demineralization have on enamel’s ability to absorb fluoride?

Increases absorption capability Signup and view all the answers

What limits the maximum uptake of fluoride in tooth enamel?

Surface abrasion Signup and view all the answers

What happens to the pH during the process of remineralization?

It increases Signup and view all the answers

What is the primary mineral lost from hydroxyapatite during the demineralization process?

Calcium Signup and view all the answers

What is a significant reason why fluoroapetite is important in dental health?

It is less soluble than hydroxylapatite. Signup and view all the answers

How does fluoride from topical applications contribute to tooth remineralisation?

It creates a reservoir in saliva that releases fluoride when needed. Signup and view all the answers

What is the critical pH at which fluoroapetite begins to demineralise?

4.5 Signup and view all the answers

What effect does the presence of larger crystals in fluoroapetite have?

It enhances resistance to future acid attacks. Signup and view all the answers

What is the fluoride concentration in fluoride varnish?

22,600ppm Signup and view all the answers

How should fluoride toothpaste be used according to prescription guidelines?

A higher concentration is prescribed for specific cases. Signup and view all the answers

What is one method of ensuring a regular supply of fluoride?

Regular professional fluoride treatments. Signup and view all the answers

What role does calcium fluoride (CaF2) play during acid attacks?

It releases fluoride when pH drops. Signup and view all the answers

Which fluoride product has the highest concentration?

Fluoride varnish Signup and view all the answers

Why is a regular low-level supply of fluoride essential in caries prevention?

It supports the remineralisation process, replacing lost ions. Signup and view all the answers

Study Notes

Fluoride and the Tooth Surface

Fluoride is absorbed into tooth surfaces, making them more resistant to demineralization.
This occurs at multiple stages, including pre-eruptive and post-eruptive stages.
Pre-eruptive fluoride (systemic) is absorbed via the bloodstream and deposited into the developing tooth during enamel formation.
Post-eruptive fluoride (topical) is absorbed into the surface of the tooth during remineralization after demineralization.
Fluoride uptake occurs during the first 2-3 years post-eruption.
Demineralisation occurs when pH drops below critical levels (5.5 for hydroxyapatite).
Demineralisation results in a loss of calcium and phosphate ions from hydroxyapatite.
Fluoride replaces hydroxyl ions in the hydroxyapatite structure, creating fluoroapatite.
Fluoroapatite is more stable than hydroxyapatite, making the teeth more resistant to further acid attacks.
Regular fluoride intake is vital to replace lost ions to maintain the process of prevention.
Topical fluoride applications create a reservoir in saliva, enabling fluoride to be available during remineralization.
Tooth surface wettability is affected.
Fluoride reduces bacterial adhesion on tooth surfaces.
Fluoride can affect tooth morphology, creating shallower pits, reduced fissure depths, and lower cusp heights
Root caries are more likely to develop in areas where enamel has been lost.
This happens because root surfaces are less mineralised and so are more susceptible to decay.
Fluoride incorporation into the root surface during remineralisation, reduction of surface wettability, and antibacterial effects, help to prevent root caries.

GDC Learning Outcomes

Describe the properties of relevant medicines and therapeutic agents, discussing their application to patient management.
Provide comprehensive and accurate preventative education and instruction to patients, encouraging self-care and motivation.
Underpin all patient care with a preventative approach to contribute to long-term oral and general health.
Advise on and apply preventative treatments and materials as appropriate.
Describe and evaluate the role of health promotion in terms of changing environments, community and individual behaviours to deliver health gain.
Explain evidence-based prevention and apply it appropriately.

Pre-reading: Aetiology of Dental Caries

Susceptible tooth surface
Plaque bacteria
Fermentable carbohydrates
Time

Pre-reading: Histology of Enamel and Dentine

This section focuses on the structure of the tooth enamel and dentine.

Intended Learning Outcomes

List key milestones in fluoride history and use in caries prevention.
Outline and describe stages in fluoride deposition.
Describe modes of action of fluoride.
Explain how fluorosis occurs.
Identify and assess the severity of fluorosis.

Refresher Session: Properties of Enamel

Normal enamel is primarily hydroxyapatite (Ca10(PO4)6(OH)2).
Hydroxyapatite accounts for 96% of enamel.
Enamel is a lattice structure.
Enamel is composed of phosphate and calcium ions.

Refresher Session: Demineralisation and Caries

Demineralisation occurs when pH drops below the critical level (5.5).
Extensive demineralization can lead to caries.
Components of hydroxyapatite breakdown into calcium, phosphate, and hydroxyl ions.

Refresher Session: Stephen Curves and Demineralisation/Remineralisation

Infrequent sugar attacks correlate with less time below the critical pH, reducing demineralization.
Frequent sugar attacks mean more time below the critical pH, increasing demineralization risks.

Fluorine as a Chemical Element

Fluorine has the symbol F and atomic number 9.
It is a halogen.
It is found naturally in water, rocks, soil, and tea.
Fluorine is highly reactive with metals, forming salts or halides (fluorides).

Fluoride History

Key dates, milestones, and researchers related to fluoride and its use in caries prevention
Examples include investigations into Colorado Stain, water sampling in Arkansas, and subsequent research into water fluoridation and anti-fluoride campaigns.
Important reports in the history of fluoridation

Colorado Stain - 1916

Dr Frederick McKay documented staining on teeth in Colorado Springs.
McKay enlisted the help of GV Black to investigate the cause of the staining.
GV Black published a paper on the Colorado Stain.

Water Sampling - 1931

McKay's work led to Churchill's investigation into water source changes and potential link to mottling in Arkansas.
This involved identifying higher fluoride levels in water sources that showed mottling.

Identification of Fluoride's Anti-Caries Effect - 1932

McKay identified that though mottled, teeth exposed to higher fluoride content showed no greater chance of decay.

Shoe Leather Studies - 1930-1940

Dr H Trendley Dean researched the link between fluoride in water, mottling changes, and caries reduction.
Dean's studies exhibited increased mottling with increased fluoride, and decreased caries where water was fluoridated.

Knox Report- 1985

Review of papers evaluating links between fluoride and cancer.
Concluded no link exists between fluoridation and cancer risk.

York Report - 2000

Reviewed evidence from hundreds of studies into water fluoridation.
No association was found between fluoridation, bone fractures, or cancer.

Cochrane Review 2015

Review indicated that fluoridated water reduced caries in children's permanent teeth by 26% and deciduous teeth by 35% .
Also that infrequent exposure to critical PH reductions results in lower caries risks.
Fluoride ingestion results in 12% chance of aesthetic concerns in children (fluorosis).

Modern Day

Fluoride use in water remains a subject of debate and societal discussions.

How Does Fluoride Prevent Caries?

Fluoride is absorbed into tooth surfaces during remineralization, which makes the teeth more resistant to demineralisation.
Fluoride can reduce bacterial adhesion and affect tooth morphology.

Why is Fluoroapatite Important?

Fluoroapatite is more stable than hydroxyapatite.
This increased stability makes the tooth more resistant to acid attacks.

Where Does Fluoride Come From?

Topical fluoride applications create a reservoir in saliva, which is actively used during remineralization phases.

Topical Fluoride Sources

Fluoride levels in various topical sources.

How Does That Work in Real Life?

Diagram showing fluoride ions and hydroxyapatite/fluoroapatite in relation to pH changes.
Illustration of how demineralisation results and reduction in pH result from fluoride incorporation.

Does Fluoride Have Any Other Mechanisms of Action?

Fluoride can inhibit bacterial activity and reduce bacterial plaque.
Fluoride affects the surface energy of enamel, affecting wettability, and thus reducing bacterial adhesion.

Root Caries Recap

Gingival recession causes exposed root surfaces
Demineralisation processes occur faster for root surfaces
Xerostomia patients have reduced saliva and thus are more susceptible to root caries

How Does Fluoride Prevent Root Caries?

Incorporating into the surface during remineralization.
Reducing surface wettability.
Antibacterial effects.

What Does The Research Say?

Professionally applied fluoride reduces risk of root caries.
Self-applied fluoride reduces risk of root caries.

Fluorosis: What is it and How Does it Form?

Fluorosis is a condition associated with excessive fluoride intake, visible on developing teeth.
Fluoride intake during tooth development can result in enamel defects, termed fluorosis.
Ingestion of fluoride during tooth development can result in defects, visibly seen as opacities, lines, or yellow mottling, depending on dose and length of exposure during development.

Mechanism of Fluorosis

Excess fluoride inhibits ameloblast activity during enamel matrix formation and maturation, resulting in hypomineralisation (and hypoplasia).
Hypomineralisation leads to porous enamel.
Porous enamel readily absorbs stains, creating discolouration.

Aetiological Agents of Fluorosis

Dietary fluoride supplements, drinking water, toothpaste, and topical applications can cause excessive fluoride intake with visible implications.

Is it Fluorosis?

Description of clinical characteristics to differentiate between fluorosis manifestations and other enamel opacities.

Indices for Recording Fluorosis

Methods for quantifying and classifying fluorosis severity.

Summary (various)

Summary of fluoride deposition stages
Summary of fluoride modes of action

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the role of fluoride in enhancing tooth durability. This quiz covers the absorption processes of fluoride during both pre-eruptive and post-eruptive stages, as well as its impact on demineralization and remineralization. Test your understanding of how fluoride helps in maintaining tooth health.