The most commonly measured bacterial parameters in saliva are the levels of the mutans group streptococci and lactobacilli, which have diagnostic implications for the incidence of dental decay. Diagnostic guidelines which are applicable to children and young adults in whom most, if not all, teeth are present and in whom the rate of stimulated saliva is almost always greater than 0.5 ml/min have been developed. Dental decay is a potential health problem of considerable magnitude among elderly individuals. In elderly individuals, missing teeth, the presence of dentures, and a reduced salivary flow could confound the interpretation of salivary levels of cariogenic bacteria. In the present study, in which saliva was collected from more than 560 elderly individuals (average age, 70 +/- 8 years), there was a significant positive relationship between the salivary levels of Streptococcus mutans and increased numbers of teeth. There was a positive association between the salivary levels of S. mutans and decay when the data were stratified for the presence of a complaint of xerostomia and the presence of dentures. However, a similar analysis indicated that lactobacilli and yeasts were more likely to be associated with decay. The various variables which could influence the bacterial counts per milliliter of saliva, e.g., independent or dependent living status, complaint of xerostomia, stimulated salivary flow, salivary pH, the presence of dentures, number of teeth, and decay, were analyzed simultaneously by using a multivariable linear model. In that analysis the number of decayed teeth was significantly associated with the presence of lactobacilli (P = 0.0001) and yeasts (P = 0.025) but not with the presence of S. mutans. Our findings indicate that salivary levels of lactobacilli and yeasts, as well as the salivary levels of S. mutans, should be monitored when seeking microbial indicators that might predict the incidence of caries in elderly individuals.
Anaerobes differ in their sensitivity to oxygen, as two patterns were recognizable in the organisms included in this study. Strict anaerobes were species incapable of agar surface growth at pO 2 levels greater than 0.5%. Species that were found to be strict anaerobes were Treponema macrodentium, Treponema denticola, Treponema oralis n. sp., Clostridium haemolyticum, Selenomonas ruminatium, Butyrivibrio fibrisolvens, Succinivibrio dextrinosolvens , and Lachnospira multiparus . Moderate anaerobes would include those species capable of growth in the presence of oxygen levels as high as 2 to 8%. The moderate anaerobes could be exposed to room atmosphere for 60 to 90 min without appreciable loss of viability. Species considered as moderate anaerobes were Bacteroides fragilis, B. melaninogenicus, B. oralis, Fusobacteria nucleatum, Clostridium novyi type A, and Peptostreptococcus elsdenii . The recognition of at least two general types of anaerobes would seem to have practical import in regard to the primary isolation of anaerobes from source material.
The present study examined the hypothesis that women with eating disorders associated with a history of chronic vomiting can be characterized by a salivary flora with high levels of aciduric organisms, such as, mutans strepotococci, lactobacilli and yeast. Three groups of female subjects were studied: vomiting bulimics (G1; n = 14), and comparison groups selected for high Streptococcus mutans (G2; n = 13), and low S. mutans levels (G3; n = 12). The prevalence and levels of mutans streptococci, lactobacilli and yeast tended to be higher in bulimics than in non‐bulimics. The bulimics had significantly higher levels and higher prevalence of Streptococcus sobrinus than the non‐bulimics. A high S. sobrinus colonization may be a marker for a history of vomiting in bulimia.
The effect of sorbitol (SOR), xylitol (XYL), and the mixture XYL/SOR in chewing gums on dental plaque was studied in three groups of 7 adults (mean age 22.5 years). A fourth group of habitual users of sucrose-containing gums was used as a control. The study involved a 2-week, no-gum period followed by the use of the polyol gums for 2 weeks (10 gums/day in 5 2-gum doses). The daily consumption of XYL and SOR in the XYL and SOR groups was 10.9 g, whereas in the XYL/SOR group, 8.5 and 2.4 g of these polyols were used per day. At the end of the gum period the acidogenic response of the 48-hour plaque was tested using a 10-ml mouthrinse containing the polyols (10% w/v) present in the experimental gums, followed by a 10-ml rinse of 10% (w/v) sucrose solution. The plaque of the subjects who used XYL and XYL/SOR gums showed a significantly better ability to resist pH drops induced by the sucrose rinse than the plaque in the SOR gum group. No changes in resting pH values were observed in the XYL and XYL/SOR groups, whereas the use of SOR gum was associated with significantly lower pH values. The amount of plaque decreased in the XYL/SOR (24.3%) and the XYL (29.4%) groups, but increased in the SOR (48.3%) group, the changes in the SOR group differing significantly from those found in the other groups. The plaque and saliva levels of Streptococcus mutans generally increased in the SOR group, but decreased in groups which used XYL.
Feverfew (Tanacetum parthenium) is used for prophylaxis of migraine and it had been suggested that the plant may have antithrombotic potential. We have prepared extracts from the leaves of feverfew and have demonstrated inhibition of 14C-5HT secretion in platelet-rich plasma induced by the phorbol ester PMA, l-oleoyl-2-acetyl-sn-glycerol (OAG), arachidonic acid, the thromboxane analogue U46619, adrenaline, collagen and ADP. The effects of a solution of parthenolide (an∝-methylenebutyro-lactone isolated from feverfew) were determined in parallel. Both feverfew extract (FE) and parthenolide inhibited 14C-5HT release in a concentration-dependent manner and the effectiveness depended on the nature of the aggregating agent used. Both FE and parthenolide were most effective as inhibitors of the secretion induced by PMA and OAG. When we compared the concentrations of FE and parthenolide which gave 50% inhibition of secretion for all the agents tested, a good correlation was found (r= 0.936). Further studies showed that feverfew extract and parthenolide inhiMt release of β-thromboglobulin from platelets as well as 14C-5HT. FE did not cause liberation of LDH. Inhibition of secretion by FE appears to be irreversible since washing platelets after treatment did not restore secretory activity. The structure of parthenolide suggests that it can alkylate sulphydryl (SH) groups. When agents containing SH groups (e.g. cysteine) were added to FE, anti-secretory activity was reduced. We also obtained a considerable decrease in the number of acid-soluble SH groups in platelets treated with feverfew extract or parthenolide at concentrations which inhibit secretion. However there was a less marked decrease in the number of acid-insoluble SH groups. FE itself does not induce formation of disulphide-linked proteins but such proteins were formed when platelets were activated in the presence of FE, probably as a result of decreased glutathione levels. We conclude that parthenolide or parthenolide-like compounds are responsible for the anti-secretory effects of FE, and that alkylation of sulphydryl groups in platelets may be involved.
In the present investigation, the proportions of Streptococcus mutans, lactobacilli, Streptococcus sanguis, veillonellae, and an unidentified actinomyces-like organism in dental plaque on occlusal fissures of first mandibular molars were monitored at 6-month intervals over a 3-year period in 368 children who were initially in grades 1 or 2. Teeth destined to become decayed exhibited a significant increase in the proportions of S. mutans from 6 to 24 months before the diagnosis of dental decay. Lactobacilli were sporadically detected but when present were associated with dental decay. Children whose teeth exhibited the greatest number of decayed surfaces had, at all time periods, significantly higher proportions of S. mutans than did children who were caries free. Many teeth had high proportions of S. mutans at their entry into the study. About 10% of the monitored teeth erupted during the period of observation, and in these teeth both S. mutans and lactobacilli could be significantly associated with decay. In these newly erupted teeth S. mutans outnumbered lactobacilli by ca. 20 to 1. S. sanguis, veillonellae, and the unidentified actinomyces-like organism could not be associated with the development of decay. These findings strongly implicate S. mutans and possibly lactobacilli as dental pathogens and suggest that if decay is to be controlled by strategies based upon a S. mutans infection, then the various tactics used probably will have to be performed on primary teeth, as these teeth are the most likely sources of infection for the permanent teeth.
Taxonomic screening of subgingival plaque organisms with various enzyme assays have shown that Treponema denticela, Bacteroides gingivalis and an unspeciated Capnocytophaga species possess a trypsin‐like enzyme (TLE) that can be detected by the hydrolysis of N‐benzoyl‐DL‐arginine‐2‐naphthylamide (BANA). As these organisms can be considered to be periodontopathic, it was of interest to determine whether this BANA hydrolyzing enzyme could be detected directly in subgingival plaque samples. Subgingival plaque samples were collected from single sites of known pocket depth, and after dispersal by vortexing, aliquots were incubated overnight with BANA and were counted microscopically. The color reactions were developed with fast garnet, read by the eye and classified as positive (red to red‐orange), negative (yellow) and questionable. In the BANA‐positive plaques, the spirochetes averaged 43% of the microscopic count, whereas in the BANA negative plaques the spirochetes averaged 8% of the microscopic count. The average pocket depth of BANApositive plaques was 6.7 mm, whereas the average pocket depth of BANA‐negative plaques was 4.5 mm. When both of these parameters were combined, the presence of a positive BANA reaction was usually indicative of subgingival plaques containing >34% spirochetes removed from sites that had probing depths of 7 mm or more. Seventy‐one per cent of the plaques removed from untreated periodontal patients were BANA‐positive, while only 8% of the plaques removed from successfully treated patients seen at maintenance recall visits were BANA‐positive. These data indicate that the ability of subgingival plaque to hydrolyze BANA is a reliable marker for the presence of high proportions of spirochetes in the plaque sample and possibly could be used clinically to identify those sites and/or individuals who might require treatment to reduce this spirochetal overgrowth.
Eighty-five strains of bacterial species selected from the predominant cultivable dental plaque flora of patients with different periodontal pathologies were examined for their plasmid content. Microorganisms studied included: Actinomyces viscosus, A. odontolyticus, Bacteroides asaccharolyticus (B. gingivalis), B. melaninogenicus subspecies intermedius, and subspecies melaninogenicus, Capnocytophaga ochracea (B. ochraceus), and Fusobacterium nucleatum. Three B. melaninogenicus isolates showed plasmids of approximately 2.7-2.9 Mdalton (mega-dalton) molecular size. Restriction, enzyme digests of the plasmids demonstrated dissimilar patterns when electrophoresed on agarose gels. In other microorganisms, including the Actinomyces species, plasmids were not observed.
