Dental X-Rays and Why You Need Them
Today scientists know that X-rays are a form of radiated energy. The denser the material is when an X-rays enters the more they are absorbed. In the reverse the less they are able to pass through the object. Teeth and bone are very dense, so they absorb X-rays. Soft tissues such as cheeks, gums and skin are much less able to stop x-rays so they appear a lighter shade. The difference in densities form images and this is the key to forming an image.
On the x-ray film cheeks and gums are medium dark and cloudy and teeth show up as lighter grey. A metallic fillings is even denser than bone, and will show as a solid white area. Decay under a Resin fillings is very damaging and also the most difficult to detect. They appear similar to the tooth's dentin. Cavities will show up on an X-ray as a grayish area in a lighter area of the tooth.
Why are X-rays Used
X-ray images are one of the most valuable tools a dentist has for keeping your mouth health. By understanding how structures look like normally on an X-ray film a dentist can see and diagnose problems in the teeth and jaws. For example, the x-rays shows areas of decay that your dentist may not be able to see with just a visual examination. They may show areas of bone loss from gum disease. The following list shows common uses of dental x-rays.
- To reveal abnormalities such as cysts, fractures and changes associated with metabolic and systemic diseases.
- Finding decay that is underneath an existing filling
- Locating cracks or other damage in an existing filling
- Alerting the dentist to possible bone loss found in gum disease. Revealing problems in the bone around a root canal tooth such as an infection.
- X-rays are used to watch for decay and to monitor tooth growth, spacing, eruption and development for children
- Help your dentist plan, prepare and place tooth implants
- To find new decay areas between the teeth.
- Locating the position of unerupted teeth such as 3rd molars.
How X-rays are useful to the patient and dentist
This simple and useful diagnostic procedure is commonly misunderstood. Patients are often understandably concerned with radiation exposure. Below is a comparison of x-ray radiation you may find interesting. Notice that dental x-rays are at the very bottom of this ranked listing. We would have to take almost 10,000 dental x-rays to reach your maximum safe yearly dose! Here are some other examples.
| Type of X-Ray | Radiation |
| Lower GI series | 875 |
| Heart | 670 |
| Mammography | 1000 |
| Small Bowel | 422 |
| Lumbar spine | 347 |
| Gallbladder | 168 |
| Abdomen | 147 |
| Pelvis | 133 |
| Skull | 78 |
| Hip | 72 |
| Cervical spine (neck) | 52 |
| Leg (full) | 21 |
| Dental -full mouth series | 9 |
| Dental -panoramic | 1 |
| Dental -bitewing | 0.5 |
| Background Radiation | 300 |
| Flight from LA to NY | 4 |
Do I Need X-rays?
When you think about dental x-rays and the seriousness of conditions such as decay, periodontal disease, abscesses and fractures that are detected with x-rays and the very minor amount of radiation, it seems like a reasonable thing to do.