Ellen,

You are assuming the age of this child.  This cavity pattern in a child whom appears to be in the 3-5 year old age range (I am a pediatric dentist of 30 years, and this child appears to be that age) is attributable to Severe Early Childhood Caries.  SECC is an infectious and communicable disease involving a multifactorial etiology to exist and progress.  Education, diet, socioeconomic status, parental habits, & oral hygiene practices are just a part of it.  Fluorides play a MAJOR role in this disease process.  The literature is very clear on this, including the Cochrane Review.

The upper incisors exhibit a beginning of SECC which is typically fueled by inappropriate feedings of breast milk, cow's milk, sugar sweetened beverages, or other fermentable carbohydrates.  Harmful bacterial plaque must be present, poor oral hygiene, and the other factors listed above for this to progress.

Water fluoridation is well documented to be effective in reducing caries of SECC & ECC.

Johnny