摘要:

A new sugar substitute, Palatinit®, is an equimolar mixture of the disaccharide alcohols α-D-glucopyranosyl-1,6 sorbitol and α-D-glucopyranosyl-1,6 mannitol. Palatinit can be produced on an industrial scale from sucrose. Representative isolates of the predominant oral genera of streptococcus and actinomyces were tested for their ability to ferment Palatinit in vitro. Some strains of Streptococcus mutans, Actinomyces israelii, Actinomyces viscosus and Actinomyces naeslundii lowered the pH to below 5.5. These data, however, give no information on the rate of acid production from Palatinit or the pH drop in dental plaque in vivo. Palatinit-fermenting microorganisms were found in dental plaque of rats. Following administration of Palatinit to rats, no increase in the numbers of these microorganisms was observ

ISSN:0008-6568    

DOI:10.1159/000260419

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

The aggregates produced by mixing saliva with cells of several strains of Streptococcus mutans, unlike those of Streptococcus mitis and Streptococcus sanguis, are extremely fragile. Aggregation of S. mutans cells can be followed spectrophotometrically but cannot be detected, after mechanical agitation, in an electronic particle counter. The salivary aggregating factor for a strain of S. mutans is shown to be different from those for S.mitis and S. sanguis. These findings are consistent with the poor adhesion of cells of S. mutans to saliva-treated hydroxyapatite and the relatively low incidence of S. mutans in dental plaque.

ISSN:0008-6568    

DOI:10.1159/000260420

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Explants of developing molar teeth from 8-day-old rats were cultured in medium containing 75Se under control conditions and following chemical inhibition (DNP), heat inactivation or removal of the enamel organ. Autoradiographic patterns of 75Se uptake in the enamel organ and enamel were compared. The findings support the hypothesis that selenium is normally secreted in the matrix as it is deposited.

ISSN:0008-6568    

DOI:10.1159/000260421

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

The effects of fluoride on the initial adherence of bacteria to smooth surface enamel were evaluated in an in vivo model system. Both quantitative and qualitative changes in the colonization pattern were studied using microbiological techniques and the scanning electron microscope. Neither hourly rinsing with a 0.2% solution of NaF nor fluoride incorporated in the enamel in the form of calcium fluoride or fluorapatite influenced significantly the numbers or types of bacteria that could be recovered from the enamel test surfaces after their exposure to the oral environment for 5 h. Yet, significantly fewer bacteria, and mainly actinomycetes, were recovered from surfaces exposed hourly to a 0.373% solution of stannous fluoride. This effect may probably be ascribed to a combined adherence-interference activity of the tin ion and a bactericidal effect of the solution.

ISSN:0008-6568    

DOI:10.1159/000260422

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

The paper provides a detailed bacteriologic description of the predominant flora of supragingival plaque collected from 15 caries-free Tanzanian children exposed to negligible (0.3 ppm) and excessive (3–21 ppm) concentrations of fluoride in the water supply. The three predominant groups of bacteria in all samples were streptococci, veillonellae, and pleomorphic, gram-positive rods, which together accounted for 86.8% (mean) of cultivable flora. Streptococcus mitior was the single most predominant streptococcal species. Streptococcus mutans, mainly of serotype b, was isolated from two thirds of the samples and accounted for 2.3–21.4% of the streptococcal flora. Bacteria, which potentially metabolize lactate, i. e. veillonellae, neisseriae, propionibacteria, arachniae, Bacteroides asaccharolyticus, and Streptococcus jaecalis, comprised almost one half of the total flora (range 9–76%), and may conceivably be responsible for the negligible caries activity, despite the presence of highly acidogenic bacteria. There were no detectable differences in the flora of plaque samples from children exposed to high and low water fluoride concentrations, respectively. Previously observed fluoride-induced differences in the net metabolic product, and contents of extra- and intracellular polysaccharides of plaque, is probably to be explained by a direct interference of fluoride with plaque en

ISSN:0008-6568    

DOI:10.1159/000260423

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Topical application of 3% sodium monofluorophosphate once every 2 weeks for 1 year reduced the caries increment markedly in a group of Danish schoolchildren. The number of reversals seemed to be particularly high. The amounts of monofluorophosphate received by this treatment is low, compared with the amounts appüed by normal use of toothpaste containing monofluorophosphate. Despite this, the reduction in caries increment was higher than in most studies where monofluorophosphate toothpastes were tested

ISSN:0008-6568    

DOI:10.1159/000260424

出版商:S. Karger AG    

年代:1979

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000260425

出版商:S. Karger AG    

年代:1979

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000260426

出版商:S. Karger AG    

年代:1979

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000260427

出版商:S. Karger AG    

年代:1979

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000260418

出版商:S. Karger AG    

年代:1979

数据来源: Karger