Periodontology or Periodontics is the specialty of dentistry that studies supporting structures of teeth, diseases, and conditions that affect them. The supporting tissues are known as the periodontium, which includes the gingiva(gums), alveolar bone, cementum, and the periodontal ligament. A professional who practises this speciality field of dentistry is known as a periodontist.
Periodontal diseases take on many different forms but are usually a result of a coalescence of bacterialplaque biofilm accumulation of the red complex bacteria (egs. include P. gingivalis, T. denticola, and A. actinomycetemcomitans) of the gingiva and teeth, combined with host immuno-inflammatory mechanisms and other risk factors which lead to destruction of the supporting bone around natural teeth. Untreated, these diseases lead to alveolar bone loss and tooth loss and, to date, continue to be the leading cause of tooth loss in adults.