How is gum disease diagnosed?

Gum disease is diagnosed by both clinical (hands-on) and radiographic (x-ray) examinations. During a clinical exam, the dentist uses an instrument called a probe to measure the gums. A probe is like a small metal ruler using millimeter increments. The dentist probes the gum around the tooth and takes a series of measurements (usually six). In general, measurements of greater than 3 millimeters (called a "pocket") indicate the presence of gum disease. If the gum bleeds when the dentist gently probes it, this often indicates the presence of gum disease. Visual examination of a person with gum disease may reveal red, puffy, swollen or receding gums. Large deposits of plaque and calculus (tartar) are often visible in people with gum disease, especially those who have not seen a dentist in years. The teeth may be mobile, that is, the dentist is able to move the tooth a millimeter or two within the socket. A healthy tooth will not budge! The dentist may detect pus when putting gentle pressure on a puffy area of the gums. Foul mouth odor (bad breath) is also commonly associated gum disease.

X-rays are also helpful in the diagnosis of gum disease. The dentist will usually require a full mouth series of x-rays (18 films) or panoramic x-ray (a large picture of all of the teeth) to document the approximate level of the bone around the teeth. Bone loss appearing on the x-ray can be uniform (horizontal bone loss), uneven (vertical bone loss), or a combination of both. See also:

Periodontal tissues are the tissues that support the teeth in the jaw bone. They comprise the gums (gingiva) and the bone to which the teeth are attached. Gum disease, or periodontal disease, is diagnosed by a dentist or hygienist. They examine the gums for inflammation, i. e., swollen, red in color, or bleed easily. In diagnosing more advanced forms of periodontal disease, known as periodontitis, the dentist looks for "pockets" that form between the gums and the teeth. The severity of disease can be determined by measuring the depth of these "pockets". The deeper the pocket in millimeters, the more severe your gum disease. The dentist also looks for gum recession, which is a measure of the distance the gums have receeded to expose the root. Other symptoms dentists look for are bad breath and loose or sensitive teeth. Ulcers, lesions, or areas of discolored gums that are painful may be the signs of advanced gum disease.  If there is pus or any other type of discharge from around the teeth, this may be a sign of infection and a dentist should be immediately consulted. To remove tartar and plaque beneath the gumline , dentists or periodontists use a technique called scaling and root planing.

Bleeding and sore gums can be a symptom of gum disease. Your dentist can diagnose gum disease with a dental exam and xrays. Your dentist will look for signs of infection and bone loss around the teeth and can advise you as to the appropriate treatment.
Your dentist can diagnose gum disease by examining your mouth and conducting a thorough oral exam. Because gum disease is usually painless, you may not know you have it. That is one reason why regular dental checkups and periodontal examinations are very important. 

Here are some warning signs that you should share with your dentist:
  • gums that bleed easily
  • red, swollen, tender gums
  • gums that have pulled away from the teeth
  • persistent bad breath or bad taste
  • permanent teeth that are loose or separating
  • any change in the way your teeth fit together when you bite
  • any change in the fit of partial dentures
Always remember to brush your teeth twice a day for two minutes with a fluoride toothpaste, clean between your teeth daily, eat a balanced diet, and schedule regular dental visits for a lifetime of healthy smiles.
Your dentist usually looks at the quality of your gums (are they healthy-looking?). Then the dentist usually measures the space between the tooth and gum. 1-3mm is generally recognized as a healthy depth.

The gums should not bleed or be uncomfortable during the measuring (periodontal probing) process.

A more sophisticated way that may catch on more in the future is to rely on lab tests to screen for certain kinds of bacteria that are known periodontal pathogens.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.