Roseann Mulligan of the Ostrow School of Dentistry at the University of Southern California, and colleagues examined nearly 1,500 socioeconomically disadvantaged elementary and high school children in the Los Angeles Unified School District.
The researchers matched the children's oral health status to their academic achievement and attendance records.
The study, scheduled to be published in the American Journal of Public Health
, found children who reported having recent tooth pain were four times more likely to have a low grade point average - below the median GPA of 2.8 - when compared to children without oral pain.
Poor oral health doesn't just appear to be connected to lower grades, Mulligan
said - dental problems also seem to cause more school absences for kids and more missed work for parents.
"On average, elementary children missed a total of six days per year, and high school children missed 2.6 days.
For elementary students, 2.1 days of missed school were due to dental problems, and high school students missed 2.3 days due to dental issues," Mulligan
said in a statement.