Shre Vinayakaa Dental Clinic
Periodontal pathology is a science or a study of periodontal diseases. Periodontal diseases can affect one or more of the periodontal tissues/structures (e.g. alveolar bone, periodontal ligament, cementum and gingiva). While there are many different periodontal diseases that can affect these tooth-supporting tissues/structures, by far the most common ones are plaque-induced inflammatory conditions, such as gingivitis and periodontitis. Often the term periodontal disease or gum disease is used as a synonym for periodontitis, specifically chronic periodontitis. While in some sites or individuals, gingivitis never progresses to periodontitis, data indicate that periodontitis is always preceded by gingivitis.
In 1976, Page & Schroeder introduced an innovative new analysis of periodontal disease based on histopathologic and ultrastructural features of the diseased gingival tissue. Although this new classification does not correlate with clinical signs and symptoms and is admittedly "somewhat arbitrary," it permits a focus of attention pathologic aspects of the disease that were, until recently, not well understood. This new classification divided plaque-induced periodontal lesions into four stages: 1) initial lesion 2) early lesion 3) established lesion 4) advanced lesion
Unlike most regions of the body, the oral cavity is perpetually populated by pathogenic microorganisms; because there is a constant challenge to the mucosa in the form of these microorganisms and their harmful products, it is difficult to truly characterize the boundary between health and disease activity in the periodontal tissues. The oral cavity contains over 500 different microorganisms. It is very hard to distinguish exactly which periodontal pathogen is causing the breakdown of tissues and bone. As such, the initial lesion is said to merely reflect "enhanced levels of activity" of host response mechanisms "normally operative within the gingival tissues." Healthy gingiva are characterized by small numbers of leukocytes migrating towards the gingival sulcus and residing in the junctional epithelium. Sparse lymphocytes, and plasma cells in particular, may exist just after exiting small blood vessels deep within the underlying connective tissue of the soft tissue between teeth. There is, however, no tissue damage, and the presence of such cells is not considered to be an indication of a pathologic change. When looking at the gums they look knife like and a very light pink or coral pink. On the contrary, the initial lesion shows increased capillary permeability with "very large numbers" of neutrophils migrating from the dilated gingival plexus into the junctional epithlieum and underlying connective tissue (yet remaining within the confines of the region of the sulcus) and macrophages and lymphocytes may also appear. Loss of perivascular collagen occurs; it is thought that this is due to the degradative enzymes released by extravasating leukocytes, such that the collagen and other connective tissue fibers surrounding blood vessels in the area dissolve. When this occurs the gums will appear bright red and either bulbous or rounded, from all the excess fluid building up in the infected area. The initial lesion appears within two to four days of gingival tissue being subjected to plaque accumulation. When not generated through clinical experimentation, the initial lesion may not appear at all, and instead, a detectable infiltrate similar to that of the early lesion, explained below, appears.