You get more radiation walking outside. Digital dental xrays expose very little radiation and are not expensive. Dentists who ask for xrays are not money hungry. Xrays are the best way to diagnose an issue with your teeth.
No. We get radiation from daily life. You get radiation from using a microwave or even by standing in sunlight. Dental xrays have very low radiation, especially if the office uses digital xrays (they use a computer and not liquids to develop the xrays).
There is nothing to worry with the emergence of Digital Radiography the exposure to radiation is reduced by 50%, which is a tremendous improvement in the field of dental Imaging.
All x-rays carry risk. The radiation they introduce into your body never leaves. Over time too many scans and X-rays build up in you body and are nothing good. Keep them to a minimum and don't say OK every time your dentist wants to take some, they are a money maker for him and not good for you unless you have a specific problem you have to get fixed.