X-rays are a form of energy that can travel through or be absorbed by solid objects. X-rays are absorbed by dense objects, such as teeth and bones, and show up on X-rays as light-colored areas. X-rays pass through less dense objects, such as gums and cheeks, and appear as dark areas on the X-ray film.
X-rays provide your dentist with a valuable diagnostic tool that helps him or her assess the overall condition of your teeth and their roots, jaw placement, and overall composition of your facial bones. X-rays help your dentist visualize diseases of the teeth and surrounding tissue that cannot be seen with a simple oral examination. X-rays help your dentist find and treat dental problems early in their development, which can potentially save you money, unnecessary discomfort, and maybe even save your life.
Exactly what types of problems can X-rays help detect?
X-rays help your dentist diagnose problems in your teeth and jaws.
In adults, X-ray films can be used to:
- Show areas of decay that might not be visible with an oral examination, especially small areas of decay between teeth
- Identify decay occurring beneath an existing filling
- Reveal bone loss that accompanies gum disease
- Reveal changes in the bone or in the root canal resulting from infection
- Assist in the preparation of tooth implants, braces, dentures, or other dental procedures
- Reveal abscesses (an infection at the root of a tooth or between the gum and a tooth)
- Reveal other developmental abnormalities, such as cysts and some types of tumors
In children, X-ray films are used to:
- Watch for decay
- Determine if there is enough space in the mouth to fit all incoming teeth
- Determine if primary teeth are being lost quickly enough to allow permanent teeth to erupt properly
- Check for the development of wisdom teeth and identify if the teeth are impacted (unable to emerge through the gums)
How often should teeth be X-rayed?
The frequency of getting X-rays often depends on your medical and dental history, and current condition. Some people might need X-rays as often as every six months. Others with no recent dental or gum disease and who visit their dentist regularly might get X-rays only every couple of years. If you are a new patient, your dentist might take X-rays as part of the initial examination and to establish a baseline record from which to compare changes that might occur over time.
Below are some general guidelines your dentist might follow regarding the frequency of dental X-rays:
Dental X-ray frequency schedule for children, adolescents, and adults*
| ||New patients ||Recall patient, high risk (decay is present) ||Recall patient, no decay, not at high risk for decay ||Current or history of gum disease ||Other comments |
|* The types of X-rays are described in the document, "Types of Dental X-rays." |
|Children (before eruption of first tooth) ||Bite-wing X-rays if the teeth are touching and all surfaces cannot be visualized or probed ||Bite-wing X-rays taken every six months until no decay is present ||Bite-wing X-rays taken every 12 to 24 months if the teeth are touching and all surfaces cannot be visualized or probed ||Selected periapicals and bite-wing X-rays of areas where disease is seen in the mouth ||X-rays to check for growth and development (These are usually not indicated at this age.) |
|Adolescents (before eruption of wisdom teeth) ||Bite-wing X-rays plus periapicals or occlusal views or bite-wing X-rays plus panoramic view (A full-mouth series is indicated when there is evidence of dental disease or history of extensive decay.) ||Bite-wing X-rays taken every six to 12 months until no decay is present ||Bite-wing X-rays taken every 18 to 36 months ||Selected periapicals and bite-wing X-rays of areas where disease is seen in the mouth ||Periapical or panoramic X-rays taken to check for the development of wisdom teeth |
|Adults with teeth ||Bite-wing X-rays and selected periapicals (A full-mouth series is indicated when there is evidence of dental disease or history of extensive decay.) ||Bite-wing X-rays taken every 12 to 18 months ||Bite-wing X-rays taken every 24 to 36 months ||Selected periapicals and bite-wing |
X-rays of areas where disease is seen in the mouth
|X-rays to check for growth and development (These are usually not indicated.) |
|Adults without teeth ||Full-mouth series or panoramic X-rays (Other X-rays are usually not indicated unless specific dental disease is clinically present. || || || || |
People who fall into the high risk category who might need X-ray films taken more frequently include:
- Children — Children generally need more X-rays than adults because their teeth and jaws are still developing and because their teeth are more likely to be affected by tooth decay.
- Adults with extensive restorative work, such as fillings — These are taken to look for decay beneath existing fillings or in new locations.
- People who drink a lot of sugary beverages — X-rays are used to look for tooth decay since the sugary environment creates a perfect situation for caries to develop.
- People with periodontal (gum) disease — These are used to monitor bone loss.
- People who have dry mouth — Whether due to medicines (such as antidepressants, anti-anxiety drugs, antihistamines, and others) or disease states (such as Sjogren’s syndrome, damaged salivary glands, radiation treatment to head and neck), dry mouth requires more frequent X-rays. Dry mouth conditions can lead to caries development.
- Smokers — X-rays are taken to monitor bone loss resulting from periodontal disease. (Smokers are at increased risk of periodontal disease.)
How safe are dental X-rays?
Exposure to all sources of radiation — including the sun, minerals in the soil, appliances in your home, and dental X-rays can damage the body’s tissues and cells, and can lead to the development of cancer in some instances. Fortunately, the dose of radiation you are exposed to during the taking of X-rays is extremely small.
Advances in dentistry over the years have lead to the low radiation levels emitted by today’s X-rays. Some of the improvements are new X-ray machines that limit the radiation beam to the small area being X-rayed, higher speed X-ray films that require shorter exposure time compared with older film speeds to get the same results, and use of film holders that keep the film in place in the mouth (which prevents the film from slipping and the need for repeat X-rays and additional radiation exposure). Also, the use of lead-lined, full-body aprons protects the body from stray radiation (although this is almost non-existent with the modern dental X-ray machines). In addition, federal law requires that X-ray machines be checked for accuracy and safety every two years, with some states requiring more frequent checks.
Even with these advancements in safety, it should be kept in mind, however, that the effects of radiation are added together over a lifetime. So every little bit of radiation you receive from all sources counts.
Despite the advances in dental equipment and film, are there other ways to minimize radiation exposure received through X-rays?
First, you can and should speak with your dentist about how often X-rays are needed and why they need to be taken. While some people need X-rays taken more frequently, as noted above, current guidelines require that X-rays be given only when needed for clinical diagnosis. X-rays should not be avoided entirely, but it’s wise to take them only when needed. With this in mind, feel free to ask your dentist questions such as:
- Was there something you found in your clinical exam that you feel needs to be further examined with an X-ray?
- How will these X-rays help guide the treatment plan you have in mind for me?
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 2/23/2009...#11198