How does your cavity count compare to the population?

Not necessarily. DMFT is a cumulative biological measure that reflects genetics, fluoride exposure during tooth development, diet composition, salivary flow rate, microbiome composition, and access to dental care, in addition to brushing and flossing habits. Some people with excellent hygiene have high DMFT scores because of genetic susceptibility, deep fissure anatomy, or reduced salivary flow. Others with moderate hygiene have low DMFT because of favourable biology. The F (Filled) and M (Missing) components reflect treatment history and age more than they reflect current hygiene.

For a small minority with favourable genetics, low-sugar diets, optimal saliva chemistry, and access to regular preventive care, yes. For the 90% of adults who have experienced decay, the clinical framing has shifted away from "preventing all cavities" toward "preventing untreated cavities" and "minimising the need for complex intervention." The modern preventive emphasis is on early detection, fluoride application, and sealants for fissure-prone surfaces, not on achieving zero decay as a realistic universal benchmark.

The traditional "every 6 months" guidance is not universally evidence-based. A Cochrane Review found insufficient evidence that twice-yearly dental visits are more effective than risk-stratified intervals. Current NHS and ADA guidance recommends that recall intervals be set by the dentist based on individual caries risk: low-risk patients may be seen annually or less frequently; high-risk patients may benefit from 3-monthly reviews. The key is regular professional monitoring, not a fixed universal interval.

DMFT stands for Decayed, Missing, and Filled Teeth. It is the standard index used in dental epidemiology to measure cumulative caries experience. D counts teeth with active, untreated decay. M counts teeth lost due to caries (extracted rather than filled). F counts teeth that have been filled as a result of prior decay. A DMFT of 9.3 (the US adult average per NHANES 2017-2020) means that across your full set of permanent teeth, an average of 9.3 have been affected by decay at some point in your life. The score never decreases: a filled tooth that subsequently needs no further treatment still adds 1 to your DMFT permanently.

Yes. Twin studies have consistently found a heritable component to caries susceptibility, with heritability estimates typically in the 40 to 60% range. Genetic factors influence saliva composition and flow rate (which affects acid buffering capacity), enamel thickness and mineralisation, tooth morphology (deep fissures are more caries-prone), and immune response to Streptococcus mutans (the primary caries-causing bacteria). This explains why some people with excellent oral hygiene still develop cavities, while others with less rigorous routines remain largely unaffected.

Yes, at the early stage. When tooth decay is confined to the outer enamel layer (a "white spot lesion" or early caries), remineralisation is possible. The tooth enamel can re-absorb calcium and phosphate minerals from saliva, particularly in the presence of fluoride. Treatments include fluoride varnish application, casein phosphopeptide products, and dietary sugar reduction to reduce acid production time. Once decay progresses through the enamel into dentine, remineralisation cannot reverse the structural damage and restorative treatment (a filling) is required. Early detection is the key: a lesion caught at the enamel stage can be managed non-invasively.

In mechanistic terms, yes: dietary sugar is the primary substrate for acid-producing bacteria in the mouth, and brushing removes the bacterial film that produces the acid. Without fermentable carbohydrate exposure, the bacterial process cannot produce sufficient acid to demineralise enamel. This is why populations with very low sugar intake historically had very low caries rates regardless of dental hygiene practices. Frequency of sugar exposure matters more than total amount: constant snacking on sugary foods keeps oral pH low for longer than a single large serving. Modern dental practice gives roughly equal weight to diet and hygiene as preventive factors.

Yes. Fluoride is among the most rigorously studied preventive interventions in dentistry. It works through three mechanisms: it makes enamel more resistant to acid dissolution (forming fluorapatite instead of hydroxyapatite), it inhibits the metabolism of Streptococcus mutans, and it promotes remineralisation of early lesions. Water fluoridation at 0.7 parts per million (the current US standard) reduces caries prevalence by approximately 25% in community studies. Topical fluoride in toothpaste and varnish provides additional direct protection at the tooth surface. The evidence base for fluoride in cavity prevention is among the strongest in preventive medicine.

NHANES data shows that caries experience begins accumulating in childhood: by age 8 to 9, approximately 52% of children have had dental caries in their primary (baby) teeth. In permanent teeth, the first molars are most commonly affected first, typically erupting around age 6 and being at high risk through late childhood. By late adolescence, the majority of caries experience that will define a person's lifetime DMFT has already begun accumulating. The protective interventions that matter most, fluoride exposure, dental sealants on newly erupted molars, and dietary patterns, are most impactful in the first decade of life.

A Cochrane Review of 56 trials found that powered toothbrushes with oscillating-rotating action reduced plaque by 21% more and gingivitis by 11% more than manual brushing after three months. The effect on caries specifically is harder to measure over short trial periods, but the plaque reduction finding is consistent and clinically meaningful. The practical consideration is compliance: an electric toothbrush used for 2 minutes produces better results than a manual brush used for 45 seconds, which is the actual average manual brushing time. For people who already brush thoroughly and for the correct duration, the benefit of switching is smaller.

Tooth decay (dental caries) is the process: the bacterial demineralisation of tooth structure driven by acid produced from fermented dietary sugars. A cavity is the physical hole or structural defect that results once decay has progressed past the point of remineralisation. You can have tooth decay (active demineralisation at the enamel surface) without yet having a cavity: this is the early caries stage that can be reversed. Once a cavity has formed, the structural damage is permanent and requires restorative treatment. The DMFT index captures both the process and its consequences across a person's dental history.