BACKGROUND: Ionizing radiation is a consistently identified and potentially 
modifiable risk factor for meningioma, which is the most frequently reported 
primary brain tumor in the United States. The objective of this study was to 
examine the association between dental x-rays-the most common artificial source 
of ionizing radiation-and the risk of intracranial meningioma.
METHODS: This population-based case-control study included 1433 patients who had 
intracranial meningioma diagnosed at ages 20 to 79 years and were residents of 
the states of Connecticut, Massachusetts, North Carolina, the San Francisco Bay 
Area, and 8 counties in Houston, Texas between May 1, 2006 and April 28, 2011 
(cases). A control group of 1350 individuals was frequency matched on age, sex, 
and geography (controls). The main outcome measure for the study was the 
association between a diagnosis of intracranial meningioma and self-reported 
bitewing, full-mouth, and panorex dental x-rays.
RESULTS: Over a lifetime, cases were more than twice as likely as controls (odds 
ratio [OR], 2.0; 95% confidence interval [CI], 1.4-2.9) to report having ever 
had a bitewing examination. Regardless of the age at which the films were 
obtained, individuals who reported receiving bitewing films on a yearly basis or 
with greater frequency had an elevated risk for ages <10 years (OR, 1.4; 95% CI, 
1.0-1.8), ages 10 to 19 years (OR, 1.6; 95% CI, 1.2-2.0), ages 20 to 49 years 
(OR, 1.9; 95% CI, 1.4-2.6), and ages ≥40 years (OR, 1.5; 95% CI, 1.1-2.0). An 
increased risk of meningioma also was associated with panorex films taken at a 
young age or on a yearly basis or with greater frequency, and individuals who 
reported receiving such films at ages <10 years had a 4.9 times increased risk 
(95% CI, 1.8-13.2) of meningioma. No association was appreciated for tumor 
location above or below the tentorium.
CONCLUSIONS: Exposure to some dental x-rays performed in the past, when 
radiation exposure was greater than in the current era, appears to be associated 
with an increased risk of intracranial meningioma. As with all sources of 
artificial ionizing radiation, considered use of this modifiable risk factor may 
be of benefit to patients.