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What can a dental x-ray show your dentist? 1

How does your dentist know when you have a cavity developing between your teeth, or a wisdom tooth beneath the gumline that isn't growing in properly?

Dental x-rays provide a picture of what's happening in areas we normally cannot see. Early decay, impacted teeth, abscesses and bone loss from gum disease are all things that dental x-rays reveal.

Examples of different things a dentists uses x-rays for are shown below.

Dental Decay under an existing filling 1

An important reason to visit your dentist regularly is to make sure that no hidden cavities under existing fillings are creeping up on you. Cavities show up as dark areas on your dental x-rays.

Root Canal Therapy - Endodontic treatment in progress 1

When the nerve in a tooth is badly damaged, either by an accidental trauma or because of dental decay, sometimes your dentist (or a dental specialist like an Endodontist) will perform Root Canal Therapy, where a hole is made into the tooth and the damaged nerve (or pulp) is removed with a special file and replaced with a filling material. Usually the tooth is later fitted with a new top called a Crown to help it remain strong.



Pins & Posts 1

Sometimes, your dentist (or dental specialist) will elect to place a pin or a post in one of your teeth following Root Canal Therapy or the placement of a crown or other restoration. The pin or post provides added strength and helps anchor the crown or restoration in place.

Tooth Parts 1

A dental x-ray provides an excellent diagram of a tooth and its parts: the crown (what you see above the gumline), tooth root and tooth pulp (nerve).

Different dental fillings, early dental decay 1

Different types of dental filling materials show up differently on your dental x-rays. The bright white filling above is made of dental amalgam, while the gray filling is a "composite", white colored filling. Each type of filling material has its own purpose.

Wisdom Tooth on the way 1

Your wisdom teeth are really just a third set of molars that appear usually when you're between 17 and 21 years old. For some people the teeth don't grow in at all, and for others there are problems with straightness and having enough space. That's why it's important to see your dentist for regular checkups to make sure everything is growing as it should.

Do all patients have radiographs taken every six months? 2

No. The need for X-rays is based on the dentist's assessment of your individual needs, including whether you're a new patient or a recall patient, adult or child, or pregnant. In most cases new patients require a set of full mouth X-rays to evaluate their teeth for underlying signs of periodontal disease and for future comparison. Recall patients may require X-rays to monitor their periodontal condition or their susceptibility to tooth decay.

What is a "panoramic radiograph." 2

Just as a panoramic photograph allows you to see a broad vista such as the Grand Canyon, a panoramic radiograph allows your dentist to see the entire structure of your mouth in a single image. Typically, most dental patients have "periapical" or "bitewing" radiographs taken. These require patients to hold or bite down on a piece of plastic with X-ray film in the center. Bitewings typically determine the presence of decay in between teeth, while periapical X-rays show root structure, bone levels, cysts and abscesses.

Why do I need both types of X-rays? 2

What's apparent through one type of X- ray often is not visible on another. The panoramic X-ray will give your dentist a general and comprehensive view of your entire mouth on a single film, which a periapical X-ray cannot show. On the other hand, periapical or bitewing X-rays show a highly-detailed image of a smaller area, making it easier to see decay or cavities between your teeth. Radiographs are not prescribed indiscriminately. Your dentist has a need for the different information that each radiograph can provide to formulate a diagnosis.

Should I be concerned about exposure to radiation? 2

All health care providers are sensitive to patients' concerns about exposure to radiation. Your dentist has been trained to prescribe radiographs when they're appropriate and to tailor radiographic schedules to each patient's individual needs. By using state-of-the-art technology and by staying knowledgeable about recent advances, your dentist knows which techniques, procedures and X-ray films can minimize your exposure to radiation.

What if my dental insurance plan won't pay for the additional X-ray? 2

It's wise for all patients to know the limitations or restrictions of their dental benefits plan. To control their own costs, some insurance plans limit reimbursement to a single type of radiographic survey. Occasionally they will allow coverage for additional radiographs, providing that your dentist supplies them with adequate information demonstrating why the additional radiographs are necessary.

Nevertheless, X-rays should be taken based on need, regardless of whether or not they are covered by your dental benefits plan.

If your dental benefits policy restricts coverage to one type of X-ray, consider writing your plan purchaser (usually someone in your Personnel or Benefits department). Your dentist can help you write this letter.

Or you may want to adapt the following for your own letter. 2

Dear Benefits Director:

I am urging you to expand our dental benefits insurance policy to provide payment of benefit for periapical and panoramic radiographs. To develop an appropriate treatment plan that will meet my oral health needs, my dentist has prescribed both types of X-rays. The different information provided by each of these X-rays is medically necessary to ensure that my dentist has a complete and accurate image of my teeth and their surrounding bony structures.

Any resulting expenses would actually result in a short-term expenditure that will yield long term gains. Treating my condition today may actually reduce future insurance costs, since prevention is almost always less expensive than having to correct a problem that's been ignored too long.




  1. "Dental X-rays" from Nova Scotia Dental Association @
  2. "Dental X-rays" @

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