Why does the frequency of sugary snacks matter more than the total amount of sugar?

Each sugary snack causes an acid attack lasting a while. Frequent snacking keeps the mouth acidic and gives enamel little time to recover.

How are dental caries treated?

Early lesions can be reversed with fluoride varnish and better brushing. Cavities are drilled clean and filled, and deep decay may need root canal treatment or extraction.

How can dental caries be prevented?

People can brush twice a day with fluoride toothpaste and cut the frequency of sugary food and drink. Regular dental check-ups and fissure sealants on children's molars also help.

What are fissure sealants?

Fissure sealants are thin plastic coatings painted into the grooves of back teeth. Food and bacteria can no longer collect in the grooves.

CCEA A-Level Life and Health Sciences 0008

Experimental Techniques

Topic overview Standard solutions, titrations and qualitative tests Rates of reaction and organic preparations Physics measurements: oscillations, resistivity, lenses and critical angle Biological tests, colorimetry, chromatography and osmosis

Human Body Systems

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Genetics, Stem Cell Research and CloningA2 option

Topic overview DNA structure and the evidence for the double helix RNA, genes and the triplet code Genotype, phenotype and monohybrid inheritance Dihybrid crosses, epistasis and the chi-squared test DNA replication and the Meselson–Stahl experiment Meiosis and genetic variation Insulin, factor VIII and chymosin from genetically modified microbes Recombinant DNA technology and gene cloning Genetic engineering, food supply and ethics Gene therapy and cystic fibrosis Genetic disease, screening and counselling Genetic fingerprinting and gel electrophoresis Stem cells, therapeutic cloning and their ethics

MicrobiologyDouble Award

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Oral Health and DentistryDouble Award

Topic overview Structure of the mouth and the five basic tastes Salivary glands, saliva and the composition of teeth Ingestion, teeth and digestion in the mouth Dental caries and acid erosion Periodontal disease, tooth loss and dental antibiotics Dental materials, prosthodontics and the dental team

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Analytical Chemistry TechniquesDouble Award

Topic overview Volumetric analysis in industry and healthcare Applied titrations of vinegar, indigestion tablets and bleach Redox titration of iron tablets and evaluating titrations Principles of colorimetry Colorimetric analysis of copper ore, aspirin and iron Thin-layer chromatography and its uses Visualising chromatograms and identifying painkillers and pigments Calorimetry and combustion Molar enthalpy and bond energy calculations Qualitative tests for cations and gases

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Topic overview ECG and EEG machines in patient monitoring Ultrasound and IVF equipment in fertility treatment Prosthetic limbs, hearing aids and cochlear implants Workflow and equipment in a medical laboratory Ongoing monitoring of a long-term condition Health data collection, databases and data protection

Oral Health and Dentistry

Dental caries and acid erosion

3 things to know
A2 7

Overview

How caries develop and the critical pH, sugar frequency, treatment and prevention, fissure sealants, acid erosion from bulimia and reflux, an eggshell investigation and testing mouthwashes.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

Zones of inhibition are 22 mm and 14 mm across for two mouthwashes. How much larger is the first zone's area?

Key term

How do dental caries develop?

Key term

At roughly what pH does enamel begin to dissolve?

Questions from this subtopic

Each one with the model answer underneath.

1
How do dental caries develop?
Model answer
Bacteria in plaque, such as Streptococcus mutans, ferment sugars into acid. The acid dissolves the minerals in enamel, and repeated attacks form a cavity.
2
At roughly what pH does enamel begin to dissolve?
Model answer
Enamel begins to dissolve when the pH at the tooth surface falls below about 5.5. Saliva then slowly raises the pH and allows some repair.
3
Why does the frequency of sugary snacks matter more than the total amount of sugar?
Model answer
Each sugary snack causes an acid attack lasting a while. Frequent snacking keeps the mouth acidic and gives enamel little time to recover.
4
How are dental caries treated?
Model answer
Early lesions can be reversed with fluoride varnish and better brushing. Cavities are drilled clean and filled, and deep decay may need root canal treatment or extraction.
5
How can dental caries be prevented?
Model answer
People can brush twice a day with fluoride toothpaste and cut the frequency of sugary food and drink. Regular dental check-ups and fissure sealants on children's molars also help.
6
What are fissure sealants?
Model answer
Fissure sealants are thin plastic coatings painted into the grooves of back teeth. Food and bacteria can no longer collect in the grooves.

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