Can kids’ teeth reveal emotional trauma? A new study suggests yes

Many parents collect their kids’ baby teeth as keepsakes when they fall out. But imagine doing it to help determine if the child has experienced emotional trauma that could lead to bigger problems later on.

A team of researchers at Massachusetts General Hospital say they plan to recruit hundreds of Boston-area women who had children around the time of the 2013 Boston Marathon bombings to test the viability of large-scale screening of baby teeth.

In a study published Tuesday, they argue that microscopic markings within children’s teeth could be a novel tool for detecting trauma. Early treatment, many doctors say, can head off health problems related to emotional wounds, especially mental health issues.

Adverse childhood experiences, such as abuse, witnessing violence, and parental drug addiction or divorce can produce toxic stress and change a child’s brain development, scientists say. Traumatic incidents are linked to chronic health problems, including heart disease, and mental health issues, such as depression and anxiety, later in life.

Finding a reliable way to measure childhood adversity and screen youngsters for risk of developing problems later in life has become a sort of holy grail among scientists and doctors, who typically rely on subjective and often inaccurate recollections of trauma long after it has taken place.

“As a scientist, you are always trying to place bets on what kind of work will make the most impact, and how you can develop better tools to prevent mental health problems in the future,” said Erin C. Dunn, an assistant professor at Mass. General and the lead researcher on the tooth study team, which also includes scientists from the Forsyth Institute and the University of California San Francisco.

Teeth are only the latest repository of information that scientists are studying for clues about childhood trauma. Researchers are also studying biomarkers in saliva, blood, and hair.

The study, published in Biological Psychiatry, describes how crucial moments in a child’s history are often recorded in their teeth. As baby teeth form before birth, and during the first few years of life, the researchers write, they develop microscopic growth marks within the hard enamel surface, much as rings in a tree mark its age.

Growth marks in baby teeth typically record daily and weekly development up to about 2 years old, whereas growth lines in some secondary or permanent teeth record development up to age 16.

Adverse experiences in childhood may affect that growth process, leaving abnormal marks or stress lines that permanently record the specific day or week in development when that stress occurred.

Most baby teeth are discarded, as are permanent teeth that are pulled during orthodontic or other dental procedures. Dunn’s team suggests they instead be saved and analyzed, along with information about family history. Just as measuring cholesterol levels in a patient’s blood can screen for potential heart disease, they propose that a close look at a child’s teeth could one day warn of possible susceptibility to trauma-related illness.

Researchers have for years studied teeth markings in the remains of ancient civilizations to better understand their history. More recently, scientists have tracked childhood exposure to chemical toxins, such as lead, by analyzing teeth.

But scrutinizing teeth to screen for potential mental health problems is new. Some researchers who reviewed the proposal thought it was a fascinating approach to a pressing problem. They said the process, however, needs to be tested on a large scale and would not likely be available at your doctor’s office anytime soon.

“It’s a really interesting new idea in a field that is desperate for measures that are relatively inexpensive and can be done in community settings,” said Dr. Jack Shonkoff, director of the Center on the Developing Child at Harvard University. Center researchers are exploring other possibilities, such as analyzing stress hormones in saliva, to screen for childhood adversity.

But some scientists are skeptical that teeth could provide a reliable reflection of any child’s emotional experience.

Tanya M. Smith, an evolutionary biologist at the Australian Research Centre for Human Evolution, has spent two decades studying teeth from the remains of prehistoric children and also from primates caged in research labs. She said even when she knows the health record and the dates of traumatic events in a primate’s life, such as being separated from its mother, it can be tough to find the corresponding stress line in the animal’s teeth.

“I am not pooh-poohing this idea [from the MGH team],” she said. “It’s just incredibly hard to do.”

Debbie Guatelli-Steinberg, an anthropology professor at The Ohio State University who also studies teeth from primates and Neanderthal remains, echoed Smith’s concerns. But she is intrigued by the idea of analyzing teeth to develop future health interventions rather than just as a window into the past.

“The most promising idea in this paper is to identify children with these defects and prospectively see what happens to them,” she said. “Are these children at higher risk for mental health later?”

The MGH team is taking steps to discover if they can first identify children who might be at risk.

Dunn said they just began recruiting women who were pregnant, or had children up to age 1, at the time of the bombing for a study called, Stories Teeth Record of Newborn Growth.

Using the Marathon bombing gives the researchers a known set point, Dunn said.

“This allows us to look at the potential impact of the bombing during these two different life stages,” Dunn said. They will be asking moms to send them their children’s baby teeth when they fall out. The researchers intend to explore how proximity to the bombing — whether the mother was running in the marathon, or watching it, or perhaps had a loved one injured — may have affected her experience and that of her unborn child or infant.

The researchers do not, at this point, have plans to follow the children to see if they develop future mental health problems. But they have not ruled it out, either.

Shonkoff, the Harvard researcher, said the development of unique biological measures of potential health risks, whether it be analysis of teeth, saliva, or other form, carries tremendous promise. But, he said, it should be used with caution.

“These biological measures need to be used by responsible people who know how to interpret them and explain them to parents,” he said. Otherwise, he said, there is potential for misuse or unintended consequences, such as losing health insurance.

“There is potential for harm by mislabeling or misclassifying, that puts kids in categories to make them disadvantaged by seeing them as higher risk,” he said. “We have to be vigilant in protecting against that.”