Preventive Dentistry and Dental Public Health
What this domain tests
This domain tests caries and oral cancer prevention, fluoride use, sealants, dietary counseling, risk assessment, and population-level prevention. Items often ask for the safest or most evidence-based preventive plan.
Core rules and concepts
- Fluoride works mainly topically through remineralization and inhibition of demineralization. Water fluoridation is adjusted to about 0.7 ppm in many systems; excessive systemic exposure during development can cause fluorosis.
- Fluoride varnish, typically 5 percent sodium fluoride, is applied professionally. Toothpaste concentration should match caries risk; high-risk patients may use higher-fluoride toothpaste under supervision.
- Sealants are indicated for deep pits and fissures, especially in high-risk children. Moisture control determines retention. Sealants can be placed over incipient non-cavitated lesions.
- Dietary prevention targets frequency of sugar exposure, not only total amount. Sugar substitutes such as xylitol can reduce caries risk.
- Oral cancer prevention includes tobacco and alcohol avoidance, HPV vaccination, and prompt evaluation of persistent lesions.
- Recall intervals should be individualized by risk, not fixed for everyone.
Worked example
A high-caries-risk child has incipient fissure lesions and poor hygiene. The reasoning is to combine fluoride varnish every 3 to 6 months, sealants on permanent molars, dietary counseling, and oral hygiene instruction. One modality alone is weaker; the plan should match the risk level and be reviewed at recall.
Traps that cost marks
Do not prescribe systemic fluoride without assessing water fluoride exposure. Do not assume sealants require removal of all caries; non-cavitated lesions can be sealed. Do not apply the same recall interval to every patient. Also avoid confusing fluoride concentration with total ingested dose.