[MUSIC] Hello. In this session we're going to discuss the contributing factors to periodontal disease. These are factors, which in themselves, do not initiate, but rather predispose or modify the progression of periodontal disease. There are two such factors, we can lump them into two groups. The first group are the Local Factors, those exist within the oral cavity. And the second groups are the Systemic Factors. The local factors include such factors as incorrect tooth brushing, occlusal trauma, food impaction, mouth breathings and iatrogenic dentistry. In this image, you can see the result of incorrect tooth brushing, resulting in tooth abrasion. Patients often brush teeth incorrectly with very hard toothbrush and this leads to gingival recession and worfacets exposing the roots of the teeth. In a normal alignment, teeth touch each other very tightly. When the contact is slightly open between the two teeth, that results in food impaction which can damage the gingival tissues. This picture illustrates which result in open contact. Another contributing local factor is the Iatrogenic Factor, these are incorrectly constructed restorations with overhanging ledges, over bulking contours, incomplete seal, improper occlusion. Those may actually contribute to gum inflammation by trapping bacterial plaque and rendering its removal very challenging to the patient. Occlusal Trauma is another factor and it is defined as injury to attachment apparatus as a result of excessive occlusal force. There are two types of Occlusal Trauma. In Primary Occlusal Trauma, the forces acting on teeth exceed their capacity. And secondary occlusal trauma, these are normal occlusal forces acting on a weakened periodontium. The best way to explain would be a very heavy person sitting on a regular, well-constructed chair and breaking the chair. Secondary occlusal trauma would be akin to a normal person with normal weight sitting on a damaged chair and breaking. In both cases, the result is the same, but the cause is quite different. So while occlusal trauma does not initiate or accelerate inflammatory effect of periodontal disease. It may have an adverse effect on the supporting bone of the tooth and increase it's mobility. These pictures on occlusal trauma demonstrate what happens when posterior teeth are extracted without subsequently being replaced. The occlusal forces are shifted to the anterior teeth, which are unable to withstand the pressure. As a result, these teeth drift, spread, and become loose. The lower jaw over-closes and the ability to chew food is severely compromised. This condition is known as Posterior Bite Collapse. And it often happens in those patients who extract their back teeth or are not willing to have them replaced. The systemic factors include age, smoking, diabetes mellitus, pregnancy, puberty, stress, genetics and heredity. Older people have higher rate of periodontal disease. Center of disease control estimates that over 70% of Americans 65 years and older have Periodontitis. Keeping in mind, however, that association is just that, it is not an indication of cause and effect. Diabetes is another significant factors in periodontitis. Diabetics have more severe and prevalent form of periodontitis. Patients with diabetes have a faster rate of bone loss. Diabetic patients with periodontitis also have a high rate of acute infections, such as abscesses, and experienced delayed healing following treatment. While periodontal destruction in diabetes relates to metabolic control, periodontal infection adversely affects glycemic control. Hence improvement in one factor leads to improvement in the other. Patients who have interlocking one genotype positive have an increased inflammatory response in the presence of bacteria, increased amount of pathogens and are at an increased risk for severe periodontal disease. Above patients are less likely to respond favorably to periodontal therapy. It is important to remember that the role of genetics in periodontitis is a disease modifier, that means bacteria must be present for the disease initiation. But modifiers, such as genetics, alter the body's response to the bacterial challenge. Smoking is another important factor in pathogenesis periodontitis. There's a strong correlation between smoking and periodontal disease. In smokers have smaller reduction in pocket depth following surgery. And there's also poorer reduction in bleeding and probing death following scaling and root planing. What are the mechanisms of tobacco smoking? Well, periodontal pockets of smokers have more anaerobic bacterias, which are the more pathogenic bacteria. They have decreased amount of salivary antibodies, such as IGA and IGG. They have have fewer Helper T Lymphocytes. Depressed chemotaxis and phagocytosis of polymorpho-nucleocites exert a direct effect on periodontal tissues' attachments to fibroblast. Therefore, impaired ability to synthesize collagen enhance impaired ability to heal. Emotional stress is a significant factors in many disease and periodontitis is no exception. Emotional stress has been linked to hypertension, cancer, and compromised immune system. In the oral cavity, a strong correlation between necrotizing infection and stress has been established. Hermetologic factors have also an important influence in leukemia and various form of dysfunction. There's increased rate of periodontitis, bond resorption, and bleeding. There's a whole host of medications which can contribute to gingival pathology. Let's review them briefly. The calcium channel blocker medications which are used for hypertension results in swollen and bleeding gums. Anti-seizure medications such as dilantin have effect of gingival hypoplasia and hypertrophy. Anti-organ rejection drugs used in organ transplantation such as cyclosporin have similar effects. And last but not least, oral contraceptives and antidepressants used by many patients result in dry mouth, which result in increased gingival inflammation. Poor nutrition also can compromise the body's immune system. Obesity may increase the risk of periodontal disease and vitamin C deficiency, such as scurvy, can lead to gingival inflammation, collagen deprivation and tooth loss. There are other conditions which have been also associated with periodontitis, and those are being currently investigated. One is osteoporosis and periodontal bone loss, association between oral bacteria and respiratory disease, gum disease and cancer of the kidney, pancreas and blood. The common denominator that links periodontal disease and other diseases is the site of inflammation and this area is under current research.
