A retrospective cohort study involving 505 participants who underwent dental computed tomography (dental CT scan) suggests that the imaging technique commonly used when dentists perform dental implantation carries some cancer risk.

The study conducted by Taiwanese researchers found patients exposed to x-ray from the mandible scan were at higher risk for cancer, compared to the maxilla scan.  The former mode of scanning subjected patients to high doses of x-ray.

The common cancers associated with the x-ray exposure included thyroid cancer, leukemia and lung cancer.  Women younger than 45 years of age were more susceptible to the risk of thyroid cancer and other cancers than individuals in other groups.  The highest lifetime attributable risk of cancer incidence was 1 in 16,196 for a 30-year old woman while the risk for a 70-year man was much lower, 1 in 114,680.  (David Liu)

Wu TH, Lin WC, Chen WK, Chang YC, Hwang JJ.  Predicting cancer risks from dental computed tomography.  J Dent Res. 2015 Jan;94(1):27-35. doi: 10.1177/0022034514554226. Epub 2014 Oct 30.