Concept and practice of plaque-control

The effect of plaque control on gingivitis and periodontitis is well-documented. In short-term investigations, chemical plaque control (oral rinsing twice a day with 0.2% chlorhexidine-gluconate solution) has been effective in the prevention of human gingivitis. Experimentally produced human gingivitis heals completely within one week when the same method is employed. Tooth cleaning with oral hygiene aids every other day prevents the initiation of gingivitis. Cleaning every third or fourth day, on the other hand, prevents neither the development nor the persistence of gingivitis. A combination of oral hygiene instructions and mechanical professional tooth cleaning at proper intervals can almost completely prevent the development of both gingivitis and periodontitis. In crossover studies and studies based on the "split-mouth " technique, frequent mechanical, professional tooth cleaning is superior to oral hygiene instructions assuming the same frequency. Finally, it must be stressed that the effect of home care and professional tooth cleaning on gingivitis and periodontitis differs radically when ordinary tooth cleaning is concentrated on the "key-risk" as opposed to the "nonrisk " surfaces. Definition of Dental Plaque Dawes et al. 1963 described plaque as the soft, tenacious material found on tooth surfaces which is not readily removed by rinsing with water. The most clinically observable plaque on the smooth surfaces of the teeth along the gingival margin may be termed dentogingival plaque. Dentogingival plaque which occurs on the approximal surfaces, apical to the contact points, is termed approximal dental plaque. Plaque may be found below the gingival margin in the gingival sulcus or in the periodontal pocket and is termed subgingival plaque. We normally will find non-attaching bacteria in the most apical position of the periodontal pocket. In children and adults up to 40 years of age, interproximal dental plaque is mainly subgingival because the gingival papilla normally fills up the interproximal space. In spite of some loss of periodontal attachment, the papilla will fill up the interproximal space due to edema. After tooth cleaning, the supragingival plaque along the gingival border of the teeth reaccumulates slowly during the following two days. The thickness of the plaque increases dramatically after the third day, to a maximum after seven days. Etiology of Periodontal Disease In 1965, Lbe and associates demonstrated that clinical symptoms of gingivitis developed in students with clinically healthy gingiva within two to three weeks if dental plaque was allowed to freely accumulate. If adequate tooth cleaning was resumed, the gingival inflammation cleared up within a week. Subclinical symptoms of gingival inflammation in the form of a discharge of exudate from the gingival sulcus appear within four days if plaque is allowed to accumulate freely in the dentogingival region. Page & Schrbder have demonstrated that an initial gingival lesion develops within approximately four days from a condition of healthy gingiva if plaque is allowed to accumulate freely. Lang and associates demonstrated in 1973 that students who completely freed their teeth of plaque at least every other day, did not develop clinical symptoms of gingival inflammation over a six-week period. On the other hand, those students who cleaned their teeth only every third or fourth day all displayed signs of gingivitis. If gingivitis remains untreated, there is a gradual increase in the edema in the gingiva. The subgingival microflora undergoes a gradual transformation into a preponderance of gram-negative anaerobic rods — straight, curved and mobile. Saxe et al., Lindhe and associates have demonstrated that gingivitis induced by bacteria, if left untreated, gradually results in periodontitis. Today the interest in certain bacteria in the subgingival microflora associated with etiology of periodontitis is concentrated on: Bacteroides asaccharolyticus, Fusobacterium nudeatum, Actinomyces israelii, Eike-