[MUSIC] Hello, in this section we're going to review Periodontal Diseases. Periodontal diseases, otherwise known as gum diseases by the lay population. It is a group of diseases that affects one or more of the tissues in the attachment apparatus of the tooth meaning Cementum, Periodontal ligament, Bone. Periodontal disease is actually a collective name of many different conditions affecting the supporting apparatus of the teeth. What are the changes then during periodontitus? First of all in gingiva, there is a change in color, contour, texture, and consistency. The gingiva becomes more reddened. They are swollen. The texture varies from stippled to more shiny and edematous. And consistency is bergis and edematous. There's also bleeding and some separation. There is also bone loss, which can be more severe around some teeth than others. There is destruction of periodontal ligament and the cementum itself also undergoes changes. There's infiltration by plaque. By calculus and by endotoxins. Periodontitis is more prevalent in some geographic areas of the world such as the far east and India. It is associated with low socio-economic standing. It is definitely associated with smoking, with diabetes, and people who exercise poor oral hygiene. When it comes to tooth loss of periodontal disease, there is a certain mirror image that emerges. In other words, the left and right side of the dentition mirror each other. The posterior teeth are generally lost at a higher right than the infront teeth. And the maxillary teeth more than the mandibular teeth. That's why in people who have lost partial dentition due to periodontal disease it is more common to see a complete full upper denture, and partial lower denture. As far as gender is concerned, there is a slightly higher prevalence of periodontitis among men than women. What are then the signs and symptoms? As mentioned before, there's bleeding, swollen and reddened gums due to vasodilation. There's formation of spaces between the gum and the tooth, referred to as a pocket. Bad taste. Halitosis. Loosening and drifting of the teeth. Changes in bite. And formation of abscess. It is important to realize that in classic periodontitis. There's no linear progression. But rather a series of periods of remission and exacerbations. Similar to many other chronic diseases. Periodontal disease is an inflammatory process, caused by the presence of plaque by a film on the teeth. It is both a direct effect from the bacteria of biofilm. Otherwise referred to as a dental plug, as well as individual bacteria residing within the pockets and a collateral effect from the body's immune system that contributes to periodontal disease. It is important to remember that human fetuses are actually sterile, but bacteria are acquired after birth. And there are more than 500 species of bacteria which establish residence in the mouth. It is also important to remember that most bacteria are beneficial, but several have been identified as pathogens. To identify pathogens in the oral cavity is a rather challenging task. It is much easier to detect a bacterial infection in a sterile environment. Such as a urine infection or blood infection. But since the oral cavity is not sterile, identifying bacterial pathogen is quite challenging. Emerging evidence from the last two decades shows that there is a strong link between periodontal disease and other systemic conditions. Such as cardiovascular disease, the common link here is inflammation. Periodontal disease therefore has been associated with other inflammatory states such as heart disease, strokes, kidney disease, pre-term birth, and other conditions. How did then bacteria cause periodontitis? There are direct bacterial effects. Bacteria release enzymes such as proteases, collagenases, fibrionlysin, and phospholipase. Parts of cells walls of gram negative bacteria are the endotoxins which are also the Lipopolysaccharides and those stimulate osteoclastic activity, which is bone resorption. There's also the indirect effect on the bacteria. Through immune system and inflammation. The polymorphionuclear leukocytes via phagocytosis and opsonization, spill lysozymes, degranulation, causing tissue destruction. Activation of monocytes, lymphocytes, fibroblasts by lipopolysaccharides to produce cytokines and inflammatory mediators such as prostaglandins, which in turn stimulate collagenases destructive to extracellular matrix and bone. Cytokines and interleukin stimulate plasma cells to produce antibodies, resulting in osteoclastic activity. Tumor necrosis factor stimulates the production of matrix proteinases. So in other words, to summarize there are two mechanisms. There is a direct bacterial effect and there is also the mediated effect through inflammation and immunological reaction. So what does the tissue in periodontal disease look like? The fact is that they can vary from one individual to another. If you look at this image, you will see that some gums are very reddened due to vasodilation, and bleed easily on probing while other gums look darker in color and have bluish appearance.