No matter how it is defined, ECC is widespread and is, in fact, endemic in low-income and native communities in the US. There is no other disease that is more common. According to the American Academy of Pediatric Dentistry, ECC affects not only teeth, but consequences of this disease may lead to more widespread health issues. Infants with ECC grow at a slower pace than caries-free infants. Some young children with ECC may be severely underweight because of associated pain and the disinclination to eat. Failure to prevent this infectious disease results in poor oral health later in life and has immediate health consequences - for instance, pain, inability to chew solid foods or to communicate effectively. However, following therapeutic intervention, children with ECC exhibit significant "catch-up" growth.

It has been known for some time that ECC is an infectious and transmissible disease primarily related to the presence of the cariogenic bacteria, mutans streptococci (MS), although it is not in itself sufficient for caries development. Besides bacteria, diet and oral hygiene are major factors in ECC. It is also considered a multi-factorial disease, with numerous biological, psychosocial and behavioral risk factors that vary from population to population.

Children at elevated risk of acquiring dental caries are often covered for dental services by Medicaid with its comprehensive Early & Periodic Screening Diagnostic and Treatment Services (EPSDT) or by State Children's Health Insurance Programs (SCHIP) which generally provide routine dental care.

MS are only present in the mouths of infants following the eruption of teeth. MS cannot colonize within the mouth without hard surfaces. The infant acquires MS from his/her mother through frequent and intimate contact. It has been demonstrated that children whose mothers had high levels of MS tend to become infected with this bacteria during a discrete period of time, or "window of infectivity."