Community Dentistry and Dental Public Health: Measuring and Preventing Oral Disease
Community Dentistry and Dental Public Health in the MDCN assessment tests epidemiology, oral health indices, prevention, and service planning. Questions ask you to interpret population data and choose proportionate, evidence-based prevention rather than individual treatment alone.
Indices and measurement
DMFT and dmft count decayed, missing, and filled teeth; they measure past and present caries experience, not current activity alone. CPITN or BPE records periodontal treatment need. Distinguish prevalence (proportion affected at a point in time) from incidence (new cases over a period). Compare groups using standardised age bands and criteria.
Prevention
Fluoride is the cornerstone: water fluoridation, toothpaste with 1000–1500 ppm fluoride, and professional varnish at 22,600 ppm for higher-risk patients. Fissure sealants reduce occlusal caries in susceptible molars. Diet advice should target frequency of sugar exposure, and supervised toothbrushing supports young children.
Worked example
A district reports 5-year-olds with dmft 4.2 and 60% of caries untreated. The reasoning is to plan population prevention and access: supervised toothbrushing, fluoride varnish, sealants for at-risk molars, and treatment capacity for existing disease. Repeating the survey later measures change.
Traps that cost marks
- Confusing prevalence with incidence.
- Comparing crude DMFT across different age groups without standardisation.
- Assuming a high DMFT means high current treatment need without checking untreated decay.