Copyright ©版权归生物谷所有，若未得到Bioon授权，请勿转载。
在美国，过去频繁接受牙科X光检测的人们在脑癌早期诊断中风险明显增加，近日刊登在杂志Cancer上的一篇研究报告中报道了这一结果，尽管牙科X光在很多时候很有必要，但是研究者的研究发现提示了适度的X光检测对于个体来说还是很有必要的。
电离辐射是引起脑膜瘤最主要的环境危险因子，而脑膜瘤在美国是最为频繁的脑癌初期的诊断。牙科X射线是主要的电离辐射来源。为了测定牙科X射线与脑膜瘤风险之间的关系，来自耶鲁大学的研究者Elizabeth Claus从2006年5月至2011年4月期间收集了年龄段为20-79之间的1433个进行疾病诊断的病人的相关信息，对照组为1350个没有经过脑膜瘤诊断的相似的人群。
结果显示，患有脑膜炎的病人进行牙科X射线检测治疗的次数是对照组两倍以上，而且每个月进行牙科X检测的病人或者更为频繁的检测的病人相比对照更容易患上脑膜瘤。脑膜瘤增加的风险也和曲面体层X线机测试相关（这种测试就是对所有牙齿进行体外显影）。在早年结构过这样的检测或者更为频繁检测的病人更容易患上脑膜瘤，每年接受过多次这种检测的病人患上脑膜瘤的风险是对照组的2.7-3倍。
研究者指出，相比过去，如今的牙科医生接受的辐射很少了。按照美国牙科协会的指导原则，儿童1-2年只需接受一次X射线检测，青少年1.5-3年接受一次检测，成年而每隔2-3年需要进行一次检测。早在2006年，牙科协会就指出了牙科X射线检测必须安全可靠，尤其是不能对病人产生负面影响，相信研究者的这项研究会给牙科的检测提供新的视野和建议。（生物谷：T.Shen编译）
Copyright ©版权归生物谷所有，若未得到Bioon授权，请勿转载。
doi:10.1002/cncr.26625
PMC:
PMID:
Dental x-rays and risk of meningioma
Elizabeth B. Claus MD, PhD1,2,§,*, Lisa Calvocoressi PhD1, Melissa L. Bondy PhD3, Joellen M. Schildkraut PhD4, Joseph L. Wiemels PhD5, Margaret Wrensch PhD5,6
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.
