Article Accessed December 28th 2014
Article published by the American Dental Association

Radiation Exposure

Radiation exposure associated with dentistry represents a minor contribution to the total exposure from all sources. The National Council on Radiation Protection and Measurements (NCRP)[1] has estimated that the mean effective radiation dose from all sources in the United States is 6.2 millisieverts (mSv) per year, with about 3.1 mSv of this dose from natural sources and about 3.1 mSv from man-made sources. About half of the man-made radiation exposure is related to CT scanning.

Occupational exposure in dental settings is far lower than that in hospitals and medical offices. According to the NCRP, the total limit for occupational exposure is 50 mSv in one year. In addition, the lifetime occupational effective dose is limited to 10 mSv times the number of an individual’s age. The NCRP concludes that occupational exposure for dental personnel will not exceed these limits, excepting for problems associated with facility design, diagnostic equipment performance, or operating procedures. For pregnant dental personnel, the radiation exposure limit is 0.5 mSv per month.

[1] National Council on Radiation Protection and Measurements. Ionizing Radiation Exposure of the Population of the United States. 2009. NCRP Report No. 160.

Radiation Safety Requirements

State laws and regulations set specific requirements for the use of ionizing radiation (which includes X-rays). Contact the state radiation protection program to determine specific requirements for:

• Inspection and testing for the facility, X-ray machine, radiation monitoring equipment and radiograph processing equipment
• Permits or licensing
• Supervision of personnel
• Use of dosimeter badges
• Training or certification
• Dental office design and radiation shielding
• Record keeping
• Equipment

Radiographic training requirements for dental office personnel frequently differ from and are less rigorous than those of medical personnel who take X-ray. Training requirements for dental office personnel typically are found in state dental practice acts or dental board regulations.

Guide to Patient Selection and Limiting Radiation Exposure

The ADA, in collaboration with the FDA, developed recommendations for dental radiographic examinations to serve as an adjunct to the dentist’s professional judgment of how to best use diagnostic imaging. Radiographs can help the dental practitioner evaluate and definitively diagnose many oral diseases and conditions. However, the dentist must weigh the benefits of taking dental radiographs against the risk of exposing a patient to X-rays, the effects of which accumulate from multiple sources over time. The dentist, knowing the patient’s health history and vulnerability to oral disease, is in the best position to make this judgment. For this reason, the recommendations are intended to serve as a resource for the practitioner and are not intended to be standards of care, nor requirements or regulations.

• Recommendations for Patient Selection and Limiting Radiation Exposure (PDF)

Additional Resources

• Managing Silver and Lead Waste in a Dental Office (PDF)
• Directory of Dental Waste Recyclers (PDF)
• The Health Physics Society (Occupational and Environmental Radiation Safety)
• FDA - Dental Radiography: Doses and Film Speed
• Radiation and Pregnancy: A Fact Sheet for the Public (Centers for Disease Control and Prevention)

Article Accessed December 13th 2014
Article published by the Canadian Dental Association 


Listed below are answers to commonly asked questions about gum disease, such as how it starts and what the early signs of the disease are. Select a question to view the Canadian Dental Association's (CDA) response.

Question 1 
How common is gum disease?

Question 2 
How does gum disease get started?

Question 3 
How can I prevent gum disease?

Question 4 
How can I tell if I'm brushing and flossing properly?

Question 5 
What if I am already in the early stages of gum disease?


1. How common is gum disease?

Very. Seven out of 10 Canadians will develop gum disease at some time in their lives. It is the most common dental problem, and it can progress quite painlessly until you have a real problem. That's why it is so important to prevent gum disease before it becomes serious.


2. How does gum disease get started?

Gum disease begins when plaque adheres at and below the visible edge of your gums. If plaque is not removed every day by brushing and flossing, it hardens into tartar (also called calculus). Tartar promotes a bacterial infection at the point of attachment. In these early stages, gum disease is called gingivitis.

Your gums may be a bit red, but you may not notice anything. As gingivitis gets more serious, tiny pockets of infection form. Your gums may be puffy and may bleed a little when you brush, but it is not painful. Over time, the infection destroys the gum tissue. Eventually, you may be at risk of losing one or more teeth.


3. How can I prevent gum disease?

Prevention is the most important factor in the fight against gum disease. It is essential to keep your teeth and gums clean. Brush your teeth properly at least twice a day and floss at least once every 24 hours.

Using proper brushing and flossing techniques is equally important. Be sure to see your dentist regularly for professional cleaning and dental exams, so that he or she can detect any early signs of gum disease, and provide appropriate treatment.


4. How can I tell if I'm brushing and flossing properly?

Brushing: Brush your teeth gently, paying special attention to the areas where your teeth and gums meet. Clean every surface of every tooth. Use the tip of your brush to clean behind your upper and lower front teeth.

Flossing: Take a piece of floss about 18 inches long and wrap it around your middle fingers. Using a clean section of floss each time, wrap the floss into a C shape around a tooth. Wipe it over the tooth, from base to tip, a couple of times. Repeat on each tooth.


5. What if I am already in the early stages of gum disease?

If you have gum disease, getting rid of plaque and tartar gives your gums a chance to get better. That's why in the early stages of gum disease, the best treatment is:

Cleaning by your dentist or dental hygienist to remove built-up tartar, brushing twice a day to remove plaque and flossing once a day to remove plaque.

When gum disease is more serious, your dentist may refer you to a dental specialist called a periodontist. A periodontist has a least three years of extra university training in treating gum disease, and in restoring (or regenerating) bone and gum tissue that have been lost because of gum disease.

A periodontist also treats serious forms of gum disease that do not get better with normal dental care. When serious gum disease is found, brushing and flossing become even more important.