Every day, the human body is constantly exposed to natural radiation, though in small amounts that are not harmful to health. Natural radiation sources are diverse, such as:

•  Terrestrial radiation – materials like sandstone, ceramic tiles, or stone have radioactive properties
•  Cosmic radiation – emitted by the Sun, planets, or other cosmic bodies
•  Internal radiation – the potassium isotope found in all living organisms has a radioactive effect
•  Atmospheric radiation – radon, a radioactive agent originating from rocks and soil, spreads into the atmosphere

There are also man-made sources of radiation, to which we are exposed depending on our interaction with radiation-emitting devices:

•  Radiation from electronic devices – TV screens, computer monitors, mobile phones, or microwave ovens
•  General radiology – chest X-rays, mammograms
•  Nuclear medicine – functional analysis of organs using radiotracers
•  Dental radiology

The unit of measurement for radiation dose is the Sievert (Sv), and the health risk of radiation exposure is measured in Millisieverts (mSv).

The average background radiation dose absorbed by each person is 0.1 mSv per day, or about 3.6 mSv per year. Of the total radiation absorbed by a person, 81% comes from natural sources, and only 19% from artificial sources.

Contrary to popular belief, dental X-rays do not affect the body as much as other types of radiological exams. During a traditional dental X-ray exposure, the patient absorbs 5 microsieverts of radiation, and only 1 microsievert during a digital radiograph — a negligible amount, with no long-term health effects.

By comparison, the average daily dose of cosmic radiation that penetrates the Earth’s atmosphere and is absorbed by each of us ranges between 5 and 8 microsieverts.
Modern technology allows even traditional X-rays to be up to 80% less harmful than in the past. Therefore, fear of radiation should not be a barrier to regular dental check-ups, which you have every reason to attend conscientiously.

Although the choice of radiograph type belongs to the dentist, being informed about the types of exposure and their implications can give patients realistic expectations regarding dental treatment.

### Radiation dose reference (in mSv – Millisievert)

| Activity / Procedure | Dose (mSv) |
| ————————————- | ———- |
| Eating a banana | 0.0001 |
| Airport security scan | 0.0025 |
| Intraoral X-ray | 0.0025 |
| OPG (panoramic X-ray) | 0.01 |
| CBCT – single arch | 0.016 |
| CBCT – full mouth (bi-maxillary) | 0.024 |
| Flight Bucharest–London | 0.025 |
| Natural background radiation (yearly) | 3.6 |
| CT scan – abdomen | 8 |