Although bacteria are the causative factor of the periodontal diseases, there are powerful influencing factors that can modify the course of the diseases such as (1) smoking, (2) genetic differences, (3) baseline severity of disease, (4) Presence of P. gingivalis, P. intermedia, and B. forsythus, and Actinobacillus actinomycetemcomitans, and (5) individual compliance with established standards for oral self-care. Of interest to married couples is the fact that spouses and children of an adult periodontitis patient might be at a relatively high risk of developing a periodontal breakdown. Another strong risk indicator is the observed relationship of several systemic diseases to gingivitis and periodontitis. Among these are diabetes mellitus, Down’s syndrome, and more rarely diagnosed conditions such as Haim-Munk syndrome and Papillon-Le Fevre syndromes. Also noticed has been a greater frequency of cardiovascular accidents and nonhemorrhagic strokes among individuals with periodontitis.
Both gingivitis and periodontitis affect the tissues of the periodontium. By definition, a plaque-induced gingivitis is an inflammation of the marginal gingiva without any loss of the epithelial attachment. Once there is a loss of the epithelial attachment, again by definition, periodontitis begins. The term periodontitis can be defined as (1) an inflammation of the marginal gingival with (2) a loss of the epithelial attachment, plus (3) irreversible damage to any of the other three remaining components of the periodontium, i.e., the cementum, alveolar bone, and the periodontal ligament that connects the latter two structures.