Periodontal disease is diagnosed by your dentist or your periodontist (gum specialist) during a periodontal examination.  This type of exam should always be part of your regular dental check-up.

A periodontal probe (small dental instrument) is gently used to measure the sulcus (pocket or space) between the tooth and the gums.  Normally, the depth of a healthy sulcus measures three millimeters or less and does not bleed.  The periodontal probe helps indicate if pockets are deeper than three millimeters.  As periodontal disease progresses, the pockets usually get deeper.  With dental X-rays (radiographs), your dentist or periodontist will use pocket depths, amount of bleeding, inflammation, tooth mobility, recession, etc., to make a diagnosis that will fall into a category below:

Gingivitis

Gingivitis is the mild and early stage of periodontal disease.  Plaque and its toxin by-products irritate the gums, making them tender, inflamed, and likely to bleed. There is no bone loss and mostly no pain at this stage.  

Periodontitis

Untreated gingivitis can progress to a more severe form of gum disease called periodontitis.  As calculus (hardened plaque or tartar) and plaque continue to build up, they can grow and spread below the gum line. Toxins produced by bacteria in the gum sulcus cause the gums to separate from the teeth, forming pockets.  When the pockets become deeper and more difficult to clean, periodontal disease continues to progress and lead to more the gum tissue and bone destruction.  This will result in gum recession, loose teeth, and eventually tooth loss if left untreated.  

There are many forms of periodontitis.  The most common ones include the following:

Chronic Periodontitis 

This is the most commonly occurring form of periodontitis.  It results in inflammation within the supporting tissues of the teeth, progressive attachment and bone loss.  It is prevalent in adults but it can occur at any age.  Progression of attachment loss usually occurs slowly, but periods of rapid progression can occur.  Moderate to advanced periodontitis occurs when the teeth lose more support as the gums, bone, and periodontal ligament continue to be destroyed.  Unless treated, the affected teeth will become very loose and may be lost. 

Aggressive Periodontitis

This form of periodontitis occurs in patients who are otherwise clinically healthy.  Common features include rapid attachment loss and bone destruction and often familial aggregation.  Often, aggressive periodontitis occurs in patients at an early age, but it could occur in patients at any age.

Periodontitis as a manifestation of systemic diseases

This form of periodontitis often begins at a young age.  Systemic conditions such as heart disease, respiratory disease, and diabetes are associated with this form.  

Necrotizing periodontal disease

It is an infection characterized by necrosis (tissue death) of the gingival tissues, periodontal ligaments, and alveolar bone around the teeth.  These lesions are most commonly observed in patients with systemic conditions such as HIV infection, malnutrition, and immunosuppression.