Concern over environmental factors in causing cancer is growing. Many seemingly harmless things (water bottles, grilled vegetables, etc) are now being labelled as carcinogenic, and are being shunned. X-rays have long been known to be carcinogenic, as the x-ray machine emits gamma radiation in controlled doses. Are dental x-rays bad for you? Can they contribute to cancer?
The link with brain cancer
Gamma radiation in theory does cause cancer. It is not good for the human body, and should be avoided. A dental x-ray involves a controlled burst of gamma radiation aimed at the face and head, which can increase the likelihood of meningioma and other forms of brain cancer. A study in the United States following 1433 meningioma patients and a control group found that the meningioma patients were twice as likely to have undergone frequent dental x-rays.
But that does not mean that dental x-rays will necessarily cause cancer, it simply means that if you frequently get dental x-rays, your likelihood of contracting cancer grows.
Dental x-rays are a necessity for certain kinds of treatment, but do not need to be made for every patient ever. Root canals, extractions (particularly wisdom tooth extractions and more severe extractions that require surgical intervention) and dental implants do require a dental x-ray. In these cases it is absolutely unavoidable. The risk of not getting an x-ray is simply too high, and can cause immediate problems or can make the procedure impossible.
The current x-ray machines in well equipped dental laboratories emit very little gamma radiation, and are far less harmful to the health than previously. Moreover, the AAD (American Association of Dentists) has ruled that getting a panoramic x-ray every 3 years or so is perfectly harmless. Getting them more frequently does increase risks, but not nearly enough to not make it worth it. As genetics, diet, and other environmental and lifestyle factors also contribute to cancer, it is very difficult to tell what exactly the main causes of this incurable ailment are. While it is best to limit contact with carcinogens and radiation, dental x-rays are a necessity, and are needed to undergo certain kinds of dental procedures.