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Cortisol is one of the primary mediators of the stress response, in the main having immunosuppressive effects. An important component of the host response in periodontal inflammation is gingival crevicular fluid (GCF), with constituents mainly derived from serum. Cortisol, like many other steroids, is present in saliva but its occurrence in GCF does not seem to be documented. Unstimulated whole saliva was collected and GCF was sampled on filter disks. The samples were analysed by a modified RIA method for serum in such a way that small volumes and low concentrations could be measured. Our findings suggest that the total concentration of cortisol in GCF might be estimated to levels below 1/10 of that in serum. However, what appears as a distinctive feature is the considerable variation of the cortisol concentrations for individual teeth. To our knowledge, this is the first time cortisol has been measured in gingival crevicular fluid, and this opens the prospects for further in vivo research. [ABSTRACT FROM AUTHOR]

This double-blind, randomised, 6-month clinical trial with parallel group design in 68 subjects with gingivitis was conducted to study the effects on the oral flora of delmopinol hydrochloride 2 mg/ml (0.2% w/v. Decapinol Mouthwash), when used for partly supervised mouthrinsing in comparison with placebo and chlorhexidine digluconate 2 mg/ml (0.2% w/v Hibitane Dental. ICI Pharmaceuticals, UK). Apart from estimating the total cultivable microbial dental plaque flora and salivary flora, analyses were focused on bacterial groups associated with gingivitis/periodontitis and dental caries. Furthermore, the presence of staphylococci. Gram-negative enteric bacteria and yeasts in saliva were evaluated. The minimal inhibitors concentration (MIC) was determined for isolates belonging to the predominating micro-organisms in samples of both dental plaque and saliva. In relation to the findings in the placebo group, the use of delmopinol during the rinsing period did not produce an undesirable shift in the bacterial populations considered to be related to dental caries or periodontal diseases. These groups remained virtually unchanged during the study. In relation to the observations in the placebo group, slight reductions in the total cultivable plaque and salivary flora were observed during the study and no change was found in the ratio total anaerobically/aerobically cultivable microbial flora. Furthermore, no increased growth in staphylococci, enteric bacteria or yeasts was observed in the saliva samples. The pattern of changes taking place in the composition of the plaque and salivary microbial flora in samples from the participants rinsing with chlorhexidine were in most aspects similar to that observed in the delmopinol group. In the delmopinol group, no microbiologically significant changes were observed over time in the MIC-values for the isolates, neither in the plaque nor in the saliva samples, which indicates that no adaptation to delmopinol had taken place during the rinsing period. Similar observations were made for the plaque isolates in samples from the participants in the chlorhexidine group. On the other hand, when Gram-positive and catalase-negative cocci from the saliva samples of the latter group were tested against chlorhexidine, 4-6 times higher MIC-values were obtained at 3 and 6 months both when compared to baseline and in comparison with the other two rinsing groups (p < 0.01 or p < 0.05). Neither delmopinol nor chlorhexidine showed any residual effect on the studied microbial groups in the plaque and the saliva samples 3 months after the end of treatment. In conclusion, delmopinol was accompanied by a composition of the plaque and salivary flora associated with healthy conditions in the oral cavity. [ABSTRACT FROM AUTHOR]

The aim of this study was to describe, in the domestic ferret, the composition of the normal gingival sulcus and the near related mucosa microflora and the shift in the composition during an acute periodontal breakdown induced by the placement of ligatures. Five animals were used. At the start of the experiment (day 0) and before the placement of the ligatures. 2 microbiological samples were obtained from the gingival sulcus and the related mucosa at the mid-buccal surface of the right upper P4. The same sites were sampled on the left side, serving as control sites. On day 28. new microbiological samples were taken from the same 4 sites. The samples were analyzed with darkfield microscopy and with viable counts. In the darkfield analysis. on day 0. the predominant bacterial morphotype was cocci, ranging from 88- 92%. The viable counts showed that nearly l00% of the total cultivable flora was composed of facultative anaerobic gram-negative and gram-positive rods. Pasteurella spp., Corynebacterium spp. and Rothia spp. were the major components of these bacterial groups. No anaerobic bacteria were detected. On day 28, cocci decreased to approximately 75% in the experimental gingival sulcus sample, and filaments and rods increased significantly. Spirochetes remained largely unchanged during the experiment. The composition of the experimental site samples changed. There was a decrease in the mean numbers of facultative anerobic gram-positive rods, and approximately one third of the microflora comprised anaerobic gram-negative rods, mainly Porphyromonas gingivalis and Fusobacterium spp. [ABSTRACT FROM AUTHOR]

The aim of this double blind, cross-over, microbiological study was to compare the effect of topical application of the plaque control agent 0.5% delmopinol HCI with placebo on early supragingival plaque formation. Six subjects underwent 7 periods (0.5, 1, 2, 8 and 24 h and 3 and 7 days) of placebo and delmopinol application, respectively. At the start of each study period the teeth were professionally cleaned and 2 ml of placebo and delmopinol 0.5%, respectively, were applied on all teeth (twice daily for periods lasting 24 h or more). At the end of each period, supragingival plaque samples of one upper and one lower buccal tooth surface were collected separately and cultured on anaerobically incubated Brucella blood agar, on aerobically incubated blood agar and on selective media for the enumeration of Streptococcus spp., Haemophilus spp., Actinomyces spp., Veillonella spp., Neisseria spp. and Fusobacterium spp. The total anaerobic cultivable microflora after delmopinol use was 10-100 times lower than after placebo use. Compared with placebo, the proportion of cultivable aerobes (61.3%), Streptococcus spp. (104.8%) and Haemophilus spp. (82.3%) increased and the proportion of Actinomyces spp. (86.1%), Veillonella spp. (60.5%), Neisseria spp. (96.9%) and Fusobacterium spp. (60.6%) decreased after 7 days. Short-term application of 0.5% delmopinol HCl on supragingival dental plaque regrowth resulted in a reduction of the number of cultivable microorganisms in the plaque and produced a shift in the cultivable plaque composition. [ABSTRACT FROM AUTHOR]

The activity of sorbitol-6-phosphate (S6P) dehydrogenase (S6PDH) and the sorbitol transport system were studied in strains of the oral streptococci Streptococcus gordonii, Streptococcus millis, Streptococcus sanguis and Streptococcus mutans. Genetically transformed (to ferment sorbitol) strains and their DNA donors were included. S6PDH was purified by anion exchange chromatography and gel filtration. The purity of the enzyme was confirmed by polyacrylamide gel electrophoresis. The purified enzyme from all the strains exhibited Michaelis-Menton saturation kinetics. The Km values for nicotinamide-adenine dinucleotide (NAD) and S6P ranged between 0.03 and 0.21 mM and 0.07 and 0.20 mM respectively. The relative molecular weights of the native enzyme were 229,000 for one donor-transformant pair (S. sanguis and S. gordonil), 107,000 for the other pair (S. sanguis and S. gordonii) and 129,000 for S. mutans. The molecular weights of the S6PDH subunits ranged from 26,000 to 28,000. The pH optima (>8.5) and the amino acid composition (15 amino acids examined) were similar for the S6PDH from the different strains. However, the chromatographic and electrophoretic patterns as well as the Km values for NAD and S6P were the same only between the S6PDHs from the strains within each donor-transformant pair. Purified S6PDH from S. mutans also exhibited low mannitol-l-phosphate dehydrogenase activity. Sorbitol-grown decryptified cells of all the strains phosphorylated sorbitol in the presence of phosphoenolpyruvate but not in the presence of adenosine triphosphate (ATP). ATP-mediated phosphorylation of glucose was observed with the same strains when grown on glucose. No evidence for a non-phosphotransferase transport system was found for sorbitol in any of the strains. The results suggest that the catabolism of sorbitol in oral streptococci involves a phosphotransferase system and the enzyme S6PDH. S6PDH from S. sanguis, S. mitis and S. mutans exhibits similarities in amino acid composition, pH optimum and subunit molecular but the Km values for NAD and S6P as well as the electrophoretic and chromatographic patterns of the enzyme differ [ABSTRACT FROM AUTHOR]