Periodontitis is inflammation of the tissues surrounding the tooth affecting the gingiva, periodontal ligaments and the bone. In its severe forms there can be a loss of bone that supports the tooth resulting in the tooth becoming loose and even causing tooth loss. The loss of supporting structures can result in the formation of periodontal pockets between the gum and the tooth. Bacteria are the primary causes of periodontal disease, and it is estimated that more than 500 different bacterial species are capable of colonizing the adult mouth. In 1968 Sigmund Socransky classified the bacterial species involved in the initiation and progression of periodontal disease. He classified several complexes of bacteria dividing them in groups, labeled by colors. The categories were based upon the pathogenicity of the bacteria and their role in the development of plaque (a bacterial microfilm).



Periodontal disease is recognized as an infectious process that requires a bacterial presence and a subsequent host response. Periodontal disease is further affected by environmental and genetic factors. Periodontitis and periodontal diseases are true infections of the mouth. In a healthy mouth there is a balance that exists between microbial count and the person’s immune response. Should there be an imbalance then a negative outcome could be clinical manifestation of periodontal disease. Bacteria located in subgingival pockets can interact with tissues even without direct tissue penetration, and the subgingival bacteria then accumulate in to form an layer of plaque with the characteristics of a biofilm. The mouth works as a continuous source of infectious agents, and its condition often reflects clinical progression of oral disease. There are several different types of periodontitis. The more common types include those below:

Chronic Periodontitis

Chronic Periodontitis is the most common type, affecting mostly adults, though children can be affected, too. This type is caused by plaque buildup and involves slow deterioration that may improve and get worse over time but causes destruction in the gums and bone and loss of teeth if not treated.

Aggressive Periodontitis

Aggressive Periodontitis usually begins in childhood or early adulthood and affects only a small number of people. It tends to affect families and causes rapid progression of bone and tooth loss if untreated.

Necrotizing Periodontal Disease

Necrotizing Periodontal Disease is characterized by the death of gum tissue, tooth ligaments and supporting bone caused by lack of blood supply (necrosis), resulting in severe infection. This type generally occurs in people with a suppressed immune system — such as from HIV infection, cancer treatment or other causes — and malnutrition.

There are many risk factors which are associated with periodontal diseases and are broadly classified into two types:

Modifiable Risk factors: Smoking, Diabetes Mellitus, Microbial deposition, Socio-economic status, Psychological factors and Nutrition.

Non-Modifiable Risk factors: Genetics, Osteoporosis, Ageing and Systemic diseases.