Antimicrobial Property of Mango Twigs Extract against Dental Caries-causing Microorganisms (Streptococcus mutans, Streptococcus sobrinus) Jervene Venturina, Santiago Bataller Jr., Raymark Camato
Dental caries is an ecological disease in which the diet, the host and the microbial flora interact over a period of time in such a way as to encourage demineralisation of the tooth enamel which results to caries formation. This disease can affect both the enamel (the outer coating of the tooth) and the dentin (the inner layer of the tooth). This is also a disease of all ages, affecting not only children but also for adults since recession of the gums are prevalent in the old ages; this occurrence exposes the tooth roots to plaque causing greater damage (Tonn, 2009) Dental caries will not occur if the oral cavity is free of bacteria. These bacteria are organised into a material known as dental plaque which is yellowish coloured film on the surface of the teeth. Of the many types of bacteria in the mouth, the most caries active appear to be Streptococcus mutans, Lactobacillus spp., Veillonella spp. and Actinomyces spp. These bacteria can be transferred from mother to child and are present at varying levels in all human mouths. A variety of carbohydrates provide substrates for these organisms to grow on and the waste products of their metabolism -acids - initiate the tooth decay process by dissolving tooth enamel. There are three major hypotheses for the etiology of dental caries: the specific plaque hypothesis, the nonspecific plaque hypothesis, and the ecological plaque hypothesis. The specific plaque hypothesis has proposed that only a few specific species, such as Streptococcus mutans and Streptococcus sobrinus, are actively involved in the disease. On the other hand, the nonspecific plaque hypothesis maintains that caries is the outcome of the overall activity of the total plaque microflora, which is comprised of many bacterial species. The ecological plaque hypothesis suggests that caries is a result of a shift in the balance of the resident microflora driven by changes in local environmental conditions. (Aas et. al, 2008). In this study we will just focus on the first hypothesis. Streptococcus mutans is a gram positive, nonmotile, facultative anaerobe. The bacteria grows optimally in the range of 18-40 degrees Celsius. S. mutans is commonly found in the oral cavity of humans and is the most cariogenic bacteria for tooth enamel. S. mutans is acidogenic meaning that it produces acid, acidoduric, able to live in acidic environments, and produces a sticky polysaccharide called dextran. Because of these properties, S. mutans is able to promote the sticking of bacteria to tooth enamel, the sticking of bacteria to other bacteria, growth of other acidoduric bacteria, and acid dissolution of tooth enamel. Streptococcus mutans was first described by JK Clark in 1924 after he isolated it from a carious lesion but it wasn't until the 1960s that real interest in this microbe was generated when researchers began studying dental caries in earnest. Carbohydrate metabolism is a key survival strategy for S. mutans, and current knowledge about sugar metabolism of this organism combined with genome data suggests that S. mutans is capable of metabolizing a wider variety of carbohydrates than any other Gram-positive organism. Genes for transport and metabolism of glucose, fructose, sucrose, lactose, galactose, mannose, cellobiose,glucosides, maltose/maltodextrin, raffinose, ribulose, melibiose starch, isomaltosaccharides, and possibly sorbose are found in the genome. In addition to sugars, S. mutans are able to convert several sugar-alcohols to glycolytic intermediates, and the genes for metabolism. This finding, in conjunction with the presence of a phosphotransferase system (PTS) transporter for pentose, suggests that S. mutans is able to synthesize and use certain pentoses. The fermentation of carbohydrates by S. mutans is the...
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Jørn A. Aas, Ann L. Griffen, Sara R. Dardis, Alice M. Lee, Ingar Olsen, Floyd E. Dewhirst, Eugene J. Leys, and Bruce J. Paster (2008). Bacteria of Dental Caries in Primary and Permanent Teeth in Children and Young Adults
Streptococcus mutans (2005) retrieved from http://www.freewebs.com/naguiar/
Marcelle M. Nascimento, José A. C. Lemos, Jacqueline Abranches, Reginaldo B. Gonçalves, and Robert A. Burne (2004) Adaptive Acid Tolerance Response of Streptococcus sobrinus. Retrieved from http://jb.asm.org/cgi/content/full/186/19/6383
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