Isolates of mutans streptococci were obtained from the dental plaque of ten subjects before and after the subjects had been free of detectable mutans streptococci for a mean period of 14.6 weeks (range, from two to 36 weeks). The mutans streptococci had been rendered undetectable by chlorhexidine varnish treatment. Examination of the restriction endonuclease analysis (REA) patterns of the isolates revealed that all ten subjects had one strain (REA type) after re-appearance of the mutans streptococci that was identical to one that had been present before the varnish treatment. In six of the ten subjects, only one strain was detected both before and after treatment. Each of the other four subjects appeared to gain a new strain after treatment; one of the four appeared to lose one strain, and another, four strains. The ability of strains to persist after the period of undetectability seemed unrelated to their resistance to chlorhexidine or to their ability to exhibit insoluble glucan-mediated adhesion. In the subjects harboring multiple REA types, one-seventh of the tooth surfaces sampled harbored two strains simultaneously, suggesting an inability of either strain to exclude the other aggressively. Overall, the study indicated that every subject receiving chlorhexidine varnish therapy had a primary strain of mutans streptococcus that re-emerged after treatment. In contrast, secondary strains were highly susceptible to being lost or gained.
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References
1.
Bammann, L.L.; Clark, W.B.; and Gibbons, R.J. (1978): Impaired Colonization of Gnotobiotic and Conventional Rats by Streptomycin-resistant Strains of Streptococcus mutans, Infect Immun22:721-726.
2.
Briner, W.; Buckner, R.; Rebitski, G.; Manhart, M.; and Banting, D. (1989): Effect of Two Years' Use of 0.12% Chlorhexidine on Plaque Bacteria, J Dent Res68:1719-1721.
3.
Caufield, P.W.; Ratanapridakul, K.; Allen, D.N.; and Cutter, G.R. (1988): Plasmid-containing Strains of Streptococcus mutans Cluster within Family and Racial Cohorts: Implications for Natural Transmission , Infect Immun56:3216-3220.
4.
Caufield, P.W. and Walker, T.M. (1989): Genetic Diversity within Streptococcus mutans Evident from Chromosomal DNA Restriction Fragment Polymorphisms, J Clin Microbiol27 :274-278.
5.
Caufield, P.W.; Wannemuehler, Y.M.; and Hansen, J.B. (1982): Familial Clustering of the Streptococcus mutans Cryptic Plasmid Strain in a Dental Clinic Population, Infect Immun38 :785-787.
6.
Davey, A.L. and Rogers, A.H. (1984): Multiple Types of the Bacterium Streptococcus mutans in the Human Mouth and their Intra-family Transmission, Arch Oral Biol29:453-460.
7.
Dunny, G.M.; Birch, N.; Hascall, G.; and Clewell, D.B. (1973): Isolation and Characterization of Plasmid Deoxyribonucleic Acid from Streptococcus mutans, J Bacteriol114 :1362-1364.
8.
Edman, D.C.; Keene, H.J.; Shklair, I.L.; and Hoerman, K.C. (1975): Dental Floss for Implantation and Sampling of Streptococcus mutans from Approximal Surfaces of Human Teeth, Arch Oral Biol20:145-148.
9.
Emilson, C.G.; Lindquist, B.; and Wennerholm, K. (1987): Recolonization of Human Tooth Surfaces by Streptococcus mutans after Suppression by Chlorhexidine Treatment, J Dent Res66 :1503-1508.
10.
Fitzgerald, R.J. and Keyes, P.H. (1960): Demonstration of the Etiologic Role of Streptococci in Experimental Caries in the Hamster, J Am Dent Assoc61:9-19.
11.
Going, R.E.; Loesche, W.J.; Grainger, D.A.; and Syed, S.A. (1978): The Viability of Microorganisms in Carious Lesions Five Years after Covering with a Fissure Sealant, J Am Dent Assoc97:455-462.
12.
Gold, O.G.; Jordan, H.V.; and Van Houte, J. (1973): A Selective Medium for Streptococcus mutans, Arch Oral Biol20 :473-477.
13.
Green, R.M.; Huxley, H.G.; Drucker, D.B.; and Black-More, D.K. (1972): Conflicting Results from the Oral Inoculation of a "Cariogenic Streptococcus" on Caries Incidence in the Hooded Rat, Arch Oral Biol17:903-906.
14.
Hagan, T.W.; Shah; G.R.; and Caufield, P.W. (1989): DNA Fingerprinting for Studying Transmission of Streptococcus mutans, J Dent Res68:407, Abst. No. 1802.
15.
Hillman, J.D.; Dzubach, A.L.; and Andrews, S.W. (1987): Colonization of the Human Oral Cavity by a Streptococcus mutans Mutant Producing Increased Bacteriocin, J Dent Res66 :1092-1094.
16.
Jordan, H.V.; Englander, H.R.; Engler, W.O.; and Kul-Czyk, S. (1972): Observations on the Implantation and Transmission of Streptococcus mutans in Humans, J Dent Res51 :515-518.
17.
Kohler, B.; Andréen, I.; and Jonsson, B. (1984): The Effect of Caries-preventive Measures in Mothers on Dental Caries and the Oral Presence of the Bacteria Streptococcus mutans and Lactobacilli in their Children, Arch Oral Biol29:879-883.
18.
Krasse, B.; Edwardsson, S.; Svensson, I.; and Trell, L. (1967): Implantation of Caries Inducing Streptococci in the Human Oral Cavity, Arch Oral Biol12:213-236.
19.
Kulkarni, G.V.; Chan, K.H.; and Sandham, H.J. (1989): An Investigation into the Use of Restriction Endonuclease Analysis for the Study of Transmission of Mutans Streptococci, J Dent Res68:1155-1161.
20.
Lindquist, B. and Emilson, C.G. (1991): Interactions between and within Streptococcus mutans and Streptococcus sobrinus isolated from Humans Harbouring both Species . In: Mutans Streptococci in Human Dentition, Thesis presented by B. Lindquist to the University of Goteborg, Reference No. VI.
21.
Little, W.A.; Thomson, L.A.; and Bowen, W.H. (1979): Antibiotic Susceptibility of Streptococcus mutans: Comparison of Serotype Profiles, Antimicrob Agents Chemother15:440-443.
22.
Loesche, W.J. (1986): Role of Streptococcus mutans in Human Dental Decay , Microbiol Rev50:353-380.
23.
Loesche, W.J.; Bradbury, D.R.; and Woolfolk, M.P. (1977): Reduction of Dental Decay in Rampant Caries Individuals Following Short-term Kanamycin Treatment, J Dent Res56 :254-265.
24.
Macrina, F.L.; Reider, J.L.; Virgili, S.S.; and Kopecko, D.J. (1977): Survey of the Extrachromosomal Gene Pool of Streptococcus mutans, Infect Immun17:215-226.
25.
Masuda, N.; Shimamato, T.; Kitamura, K.; Sobue, S.; and Hamada, S. (1985): Transmission of Streptococcus mutans in Some Selected Families, Microbios44:223-232.
26.
Olsen, G.A.; Bleiweis, A.S.; and Small, P.A., Jr. (1972): Adherence Inhibition of Streptococcus mutans: an Assay Reflecting a Possible Role of Antibody in Dental Caries Prophylaxis , Infect Immun5:419-427.
27.
Rogers, A.H. (1981): The Source of Infection of Intrafamilial Transfer of Streptococcus mutans, Caries Res15:26-31.
28.
Ruangsri, P. and Rstavik, D. (1977): Effect of the Acquired Pellicle and of Dental Plaque on the Implantation of Streptococcus mutans on Tooth Surfaces in Man , Caries Res11:204-210.
29.
Sandham, H.J.; Brown, J.; Phillips, H.I.; and Chan, K.H. (1988): A Preliminary Report on Long-term Elimination of Detectable Mutans Streptococci in Man, J Dent Res67:9-14.
30.
Schiott, C.R.; Briner, W.W.; and Loe, H. (1976): Two Years' Oral Use of Chlorhexidine in Man. II. The Effect on the Salivary Bacterial Flora, J Periodont Res11:145-152.
31.
Seppa, L.; Louma, H.; Forss, H.; Spets-Happonen, S.; Markkanen, S.; and Pelkonen, K. (1989): Invasion of Streptococcus mutans and Lactobacillus salivarius in Early Caries Lesions of Gnotobiotic Rats, Caries Res23:371-374.
32.
Svanberg, M. and Loesche, W.J. (1978): Implantation of Streptococcus mutans on Tooth Surfaces in Humans, Arch Oral Biol23:551-556.
