BACKGROUND: This study evaluates the risk of benign brain tumors (BBTs) and 
malignant brain tumors (MBTs) associated with dental diagnostic X-ray, using a 
large population-based case-control study.
MATERIALS AND METHODS: We identified 4123 BBT cases and 16 492 controls without 
BBT (study 1) and 197 MBT cases and 788 controls without MBT (study 2) from 
Taiwan National Health Insurance claim data. The risks of both types of tumor 
were estimated in association with the frequency of received dental diagnostic 
X-ray.
RESULTS: The mean ages were ~44.2 years in study 1 and 40.6 years in study 2. 
Multivariable unconditional logistic regression analysis showed that the risk of 
BBT increases as the frequency of received dental diagnostic X-ray increases. 
The BBT odds ratio increased from 1.33 [95% confidence interval (CI) 1.22-1.44] 
for those with annual mean X-ray examination of less than one to 1.65 (95% CI 
1.37-1.98) for those with three or more X-ray examinations, after controlling 
for comorbidities. No significant association was found between MBTs and dental 
diagnostic X-ray exposure.
CONCLUSIONS: Exposure to dental diagnostic X-rays in oral and maxillofacial care 
increases the risk of BBTs, but not MBTs.