Dental caries Streptococcus mutans

Mutans streptococci are the major pathogenic organisms of dental caries in humans. The pathogenicity is closely related to production of extracellular, water-insoluble glucans from sucrose by glucosyltransferase and acid release from various fermentable sugars. Poly(catechin) obtained by HRP catalyst in a phosphate buffer (pH 6) markedly inhibited glucosyltransferase from Streptococcus sorbrinus 6715, whereas the inhibitory effect of catechin for this enzyme was very low. 

The most widely studied therapeutic proteins produced in plants include monoclonal antibodies for passive immunotherapy and antigens for use as oral vaccines [40]. Antibodies against dental caries, rheumatoid arthritis, cholera, E. coli diarrhea, malaria, certain cancers, Norwalk virus, HIV, rhinovirus, influenza, hepatitis B virus and herpes simplex virus have been produced in transgenic plants. However, the anti-Streptococcus mutans secretory antibody for the prevention of dental caries is the only plant-derived antibody currently in Phase II clinical trials [40]. Until recently, most antibodies were expressed in tobacco, potato, alfalfa, soybean, rice and wheat [9], It has been estimated that for every 170 tons of harvested tobacco, 100 tons represents harvested leaves. A single hectare could thus yield 50 kg of secretory IgA [3, 41]. Furthermore, it has been estimated that the cost of antibody production in plants is half that in transgenic animals and 20 times lower than in mammalian cell cul-... 

A widespread form of dental disease, caries, is caused by acids that dissolve the mineral part of the teeth by neutralizing the negatively charged counter-ions in apatite (see A). Acids occur in food, or are produced by microorganisms that live on the surfaces of the teeth (e. g.. Streptococcus mutans). 

Chlorhexidine (C) is generally effective against all bacteria, but Streptococcus mutans and Actinomyces viscosus, two bacteria particularly associated with dental lesions, are especially susceptible to its action. Stannous fluoride (D) is widely used in caries prevention, and many studies have proven its effectiveness. 

Dental caries is one of the most common diseases in humans, and is mediated by bacteria, mainly Streptococcus mutans. It has been estimated to affect between 60 and 90% of school children in the developed world and the majority of adults [11], and is consequently a major public health concern. In addition to the developed world, it is the most widespread oral disease in many Asian and Latin American countries, though it currently appears to be less of a problem in Africa. However, changes in living conditions and increases in sugar consumption within a changing diet suggest that, in Africa too, the incidence of caries will increase, and that it will become a major public health issue here, too. 

The most common oral condition and dental emergency is dental caries, which is a destructive disease of the hard tissues of the teeth due to bacterial infection with Streptococcus mutans and other bacteria. It is characterized by destruction of enamel and dentine. Dental decay presents as opaque white areas of enamel with grey undertones and in more advanced cases, brownish discoloured cavitations. Dental caries is initially asymptomatic and pain does not occur until the decay impinges on the pulp, and an inflammation develops. Treatment of caries involves removal of the softened and infected hard tissues, sealing of exposed dentines and restoration of the lost tooth structure with porcelain, silver, amalgam, composite plastic, gold etc. 

The cariogenicity of lactitol has also been investigated. Linko et al. (1980) reviewed early studies showing that lactitol was not readily fermented by Streptococcus mutans and other oral bacteria. In vivo studies, reviewed by van Velthuijsen (1979), were concerned with the reduction of pH in dental plaque after consumption of chocolates made with lactitol, there was evidence that lactitol did not increase the incidence of dental caries. 

Streptococcus mutans Dental caries 4 g mw/day for 14 days Reduced number of S. mutans in dental plaque of adults Filler et al. 1991)... 

Hatta, H., Tsuda, K., Ozeki, M., Kim, M., Yamamoto, T., Otake, S., Hirasawa, M., Katz, J., Childers, N.K., and Michalek, S.M. 1997. Passive immunization against dental plaque formation in humans effect of a mouth rinse containing egg yolk antibodies (IgY) specific to Streptococcus mutans. Caries Res. 31, 268-274. 

Hattori, M., Hada, S., Watahiki, A., Ihara, H., Shu, Y.Z., Kakiuchi, N., Miznno, T. and Namba, T. (1986) Studies on dental caries prevention by traditional medicines. X. Antibacterial action of phenolic components from mace against Streptococcus mutans. Chemical and Pharmacological Bulletin 34, 3885-3893. 

Dental caries is a common chronic disease in which contact between teeth, food, and bacteria is involved. The major bacteria involved are believed to be Streptococcus mutans and S. sobrinus, although several Other types of bacteria are involved. Three stages have been outlined in caries adherence of bacteria to the teeth, formation of glycocalyx due to synthesis of a sticky glucan by the action of the bacterial enzyme glucosyl transferase on sucrose, and accumulation of plaque, which is a biofilm. In the dental plaque, there is continuing acid production by the bacteria, which are able to metabolize carbohydrates in acid medium, and the acid demineralizes the enamel of the teeth. 

Alaluusa A Streptococcus mutans establishment and changes in salivary IgA in young children with reference to dental caries. Proc Finn Dent Soc 1983 79(suppl 3) 1-55. 

Huis in t Veld JH, van Palenstein Helderman WH, Backer Dirks O Streptococcus mutans and dental caries in humans a bacteriological and immunological study. Antonie van Leeuwenhoek 1979 45 25-33. 

Challacombe SJ Serum and salivary antibodies to streptococcus mutans in relation to the development and treatment of human dental caries. Arch Oral Biol 1980 25 495-502. 

This chapter describes dental caries (tooth decay) and its causes. Sucrose and other mono- and disaccharides are metabolized to acid (lactate) by bacteria that remain in stagnation areas of the teeth. Rats and hamsters fed a 50% sucrose diet developed a caries-sensitive, predominantly gram-positive microbiota that became caries resistant when the rodents were fed penicillin (Sect. 1). Further studies identified Streptococcus mutans (S. mutans) as the etiological agent. This organism synthesizes an insoluble polysaccharide capsule that is stable and retains lactate at the enamel surface (Sect. 2). The key enzyme, glucosyl transferase, is related to salivary amylase which adheres to oral bacteria and enhances bacterial acid production. The chapter concludes with a discussion of salivary and other factors responsible for the marked variation observed in individual caries experience (Sect. 3). 

Fig. 15.11 Factors affecting pH after a 10% glucose or sucrose mouth rinse. Dashed line indicates pH 7. Vectors 1 and 4 increase the pH vectors 2 and 3 decrease the pH. The short-chain carboxylic acids (SCCA) may be produced from amino acids along with ammonia, or from the catabolism of lactic acid (see text and also Fig. 1.8). (From Fig. 9 in Kleinberg I, 2002. A mixed-bacterial ecological approach to understanding the role of the oral bacteria in dental caries causation an alternative to Streptococcus mutans and the specific-plaque hypothesis. Crit Rev Oral Biol Med 13 108-125)...

Dental caries is an infectious disease caused by plaque forming organisms such as Streptococcus mutans. Compounds 25 and 26, obovatol (184) and tetrahydrobo-vatol (212) showed antibacterial activity against S. mutans [177,178]. 4,4 -Diallyl-2,3 -dihydroxybiphenyl ether (213) and its mono and dimethyl ethers also showed antibacterial activity [179]. 

Apart from above industrial utilization, the water insoluble, and adherent a-(1 3)-linked D-glucans, elaborated by cariogenic Streptococcus mutans, have recently attracted much atention, in relation to the role in the formation of dental caries W. 

Most of the microorganisms are bound and/or mechanically removed via discharge of mucus from the upper respiratory tract, or via the urine, saliva, and tears, or by entrapment and elimination in the intestinal contents before they have the opportunity to multiply. Some adhere to inert bodily structures. For example. Streptococcus mutans attaches to the enamel surface of the teeth (tartar, plaque) in order to elicit dental caries [13],... 

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