Like many parents, Ariel Elliott, a Chicago mother of three girls, is no stranger to childhood tooth decay.
What makes her story different is the fact that her first child's dental problems began inexplicably and very early.
She said that when she first brought her daughter Avra to the dentist's office, her baby girl was not even a year old.
She soon learned that her daughter's teeth had already begun to decay, even before they had completely grown in.
Fortunately, the problem was caught early. But even now that Avra's dental prognosis has improved, Elliott remains puzzled as to exactly why tooth decay struck her daughter so early.
"I did all that I could," she said. "I fed them healthy, organic foods and brushed their teeth."
And now another of Elliott's daughters, 2-year-old Ilah, is experiencing similar difficulties.
"Just yesterday she [the dentist] filled four cavities in my 2-year-old's front teeth," Elliott said. "She nursed a lot, and basically it rotted her first four teeth."
Experiences like Elliott's may be on the rise across the country. According to the largest government study of the nation's dental health in more than 25 years, the prevalence of cavities in the baby teeth of children ages 2 to 5 rose to 28 percent between 1999 and 2004 -- up 4 percentage points from the 24 percent rate seen in from 1988 to 1994.
The incidence of tooth decay continued downward in other age groups, making the trend reversal in the youngest age group all the more unexpected.
Lead researcher Bruce Dye of the National Center of Health Statistics at the Centers for Disease Control and Prevention said tooth decay at this early age can have big implications for dental health later on in life.
"We do know from a number of studies that when children have tooth decay in their baby teeth, they tend to have decay later in their adult teeth," Dye said.
"It is very, very important for children to keep their baby teeth because they hold the space in the mouth for where the adult teeth come in. If a child prematurely loses his or her baby teeth, the space that develops can cause the adult teeth to come in crowded."
Some dental experts say the finding reflects what they have seen in their practices.
"The interesting thing about this particular study is that it states what, anecdotally, I have heard from all of my dental colleagues," said Mary Hayes, spokeswoman for the American Dental Association and a dentist in private practice in Chicago.
But dental experts say a host of factors may be at play, some of which suggest the findings carry more good news than bad.
At least one dental expert has suggested that the increased rate of tooth decay reported in the study could be due to better screening.
Jackson Brown, associate executive director of the American Dental Association Health Policy Resource Center, said that with more kids going to the dentist more regularly, it is inevitable that a greater number of cases of tooth decay will be detected and caught early.
"I believe this increase in prevalence among 2- to 5-year-olds is not caused by untreated decay, but it was accomplished by a greater number of cavities being filled," he said.
"These children are getting more care, and that's a good thing."
Jackson adds that, particularly for children living below and near the poverty line, the increased detection of tooth decay suggests improvements in coverage.
"This report heartens me. I feel good about it. While I think that we still have a long ways to go, this shows that disadvantaged children have gotten more care."
Hayes said if this is true, it will certainly be good news for the dental health of the country's children.
"It could be more detection -- one would hope that is the case," she said. However, she adds that there has been consistency in the research performed by the Centers for Disease Control and Prevention, a point bolstered by Dye.
"The method used in both survey periods was exactly the same," Dye said. "This is not an artifact of our ability to better detect tooth decay. The increase we saw is the number of kids who are experiencing tooth decay."
Another possible cause for the rise is the fact that today's kids drink far less tap water than they used to. Kathleen Roth, president of the American Dental Association, told ABC News medical editor Dr. Timothy Johnson, on ABC News Now's "Healthy Life" program, that with more and more parents serving their children bottled water and fruit juices, children may be missing out on a source of fluoride in tap water that has traditionally kept kids' teeth strong.
"We all know that fluoride is very important in stopping and preventing dental disease," she said, adding that parents should be sure to check the labels of bottled water, because some products on the market now have added fluoride.
Hayes agreed. "Bottled water without fluoride for children diminishes an opportunity for good dental health that they get from drinking plain tap water."
"Water with trace levels of fluoride in it has been shown to be one of the major reasons why children in this generation and the last generation have less decay than children 50 years ago."
Experts agreed, though, that traditional and preventable tooth decay culprits -- too much sugar and not enough dental care -- also played a role.
"To me it is absolutely outrageous that we have gone from 50 percent, to 25 percent, to 20 percent, but that we are still somewhere between 20 and 30 percent," Hayes said. "That's such a significant and high amount."
"I would say we still need to get back to the basics of proven oral hygiene and watch what we eat and drink and how we take care of our teeth," Dye said. "It's probably as simple as that."
Dye adds that advances in dental care, such as sealants and other new technologies, are good news for parents who want to keep their children's teeth as healthy as possible.
That includes parents like Elliott, who said she could certainly give other parents valuable advice when it comes to safeguarding their young children's teeth.
"I would tell them to take their babies to the dentist as soon as possible," Elliott said. "I think the younger you take them and the sooner you catch it, the better the prognosis. Really, nowadays, I think that as soon as they get teeth, you should get them in to the dentist."