agar and Dental-Plaque

This study aimed to investigate the possibility of applying the hyperlight fluid fusion essential complex in dental plaque control, and to evaluate the effectiveness of new and modern agents used for the prevention and early treatment of gingivitis.. The study included 60 subjects randomly divided into two groups. The control group was assigned to 0.12% chlorhexidine (CHX) mouth rinse, whereas the test group used a solution based on hyper-harmonized hydroxylated fullerene water complex (3HFWC), twice daily for 2 weeks. The plaque, gingivitis and bleeding scores were evaluated and recorded. Collected plaque samples were seeded on blood agar and incubated aerobically at a temperature of 37 °C for 24-48 hours. In order to isolate anaerobic bacteria, samples were seeded on Schaedler Agar and incubated anaerobically at 37 °C for seven days. Serial dilutions in saline from 101 - 106 were made, and grown colonies were counted and identified using the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) system.. The reduction in the number of bacteria was significant in both control and test groups. The reduction was greater in the control group compared to the experimental group, but without statistically significant difference.. 3HFWC treatment causes significant reduction in the number of dental plaque microorganisms. Since 3HFWC solution exhibited a bacteriostatic effect similar to chlorhexidine it could be an adequate addition to solution of a growing problem in prevention and early treatment of gingivitis and periodontitis.

Topics: Agar; Anti-Bacterial Agents; Anti-Infective Agents, Local; Chlorhexidine; Dental Plaque; Gingivitis; Humans; Mouthwashes

The objective of this study was to both isolate and identify non-mutans streptococci organisms (non-MSO) from dental plaques recovered on mitis-salivarius sucrose bacitracin agar (MSB) plates. The dental plaque samples, which had been collected from 63 human subjects, were diluted and plated on MSB. The bacteria growing on the MSB plates were then identified with biochemical tests, as well as with 16S rDNA cloning and sequencing techniques. Our data indicated that bacteria from 30 subjects had been recovered on the MSB plates. Among the 21 typical colonies selected from the 30 subjects, 12 colonies, derived from 10 subjects, were identified as non-MSO. These 12 colonies were determined to be Streptococcus anginosus (8 colonies), S. sanguinis (1 colony), and Pantoea agglomerans (3 colonies). These results strongly suggest that a new selective medium will be required for the reliable isolation of mutans streptococci.

Topics: Adolescent; Adult; Agar; Bacitracin; Culture Media; Dental Plaque; Humans; Streptococcus

Actinobacillus actinomycetemcomitans is considered to be one of the major oral putative pathogens, especially in cases of juvenile periodontitis. This microorganism requires nutritionally complex media for growth, and therefore the media for its primary isolation usually include blood agar or serum in their base. In this study we present a new medium, Dentaid-1, which improves the detection of A. actinomycetemcomitans in periodontal samples. In its composition, blood and serum have been omitted, hence reducing its cost and making it a more restrictive medium against the growth of other microorganisms with high nutritional requirements. The growth yields of pure cultures of the bacteria on Dentaid-1 were comparable to those on nonselective blood agar. Moreover, clinical efficacy was evaluated in subgingival samples from 77 subjects with adult periodontitis. Dentaid-1 detected A. actinomycetemcomitans in 24 subjects, while a previously described tryptic soy-serum-bacitracin-vancomycin agar detected the microorganism in only 19 subjects (79.1%). Dentaid-1 is a low-cost, noninhibitory formula for the improved diagnosis and monitoring of patients subgingivally infected by this important oral putative pathogen.

Topics: Actinobacillus Infections; Adult; Agar; Aggregatibacter actinomycetemcomitans; Bacteriology; Blood; Costs and Cost Analysis; Culture Media; Dental Plaque; Gingiva; Humans; Periodontitis; Polymerase Chain Reaction; Reproducibility of Results; Spain

This study attempted to determine which combination of plaque or saliva, and tryptic soy agar, bacitracin (TSY20B) or mitis salivarius, bacitracin media, yielded the highest caries-predictive values for mutans counts in children with different caries prevalence. Sixty children were divided into three equally sized groups: caries free, low caries and high caries. Eighteen months later, their caries incidence and initial mutans count were compared. Fissure plaque on TSY20B yielded a high correlation between mutans counts and caries prevalence (P<0.009, r=3346) and incidence (P<0.003, r=4521). The caries-predictive values obtained demonstrate that the coefficient of variation of mutans counts from lower first-molar fissure plaque on TSY20B accounts for 20.4% of the variation in final caries index. This strong correlation provides a valuable tool for the identification of caries-prone individuals.

Topics: Agar; Analysis of Variance; Child; Colony Count, Microbial; Culture Media; Dental Caries; Dental Caries Susceptibility; Dental Plaque; DMF Index; Female; Humans; Incidence; Male; Predictive Value of Tests; Regression Analysis; Risk Assessment; Saliva; Statistics, Nonparametric; Streptococcus mutans

Clinical studies have shown the efficacy of mouthrinses in reducing plaque accumulation and inflammation of oral tissues. The aim of this in vitro study was to compare the effect of three mouthrinses: Meridol, an organic amine/ stannous fluoride solution; Parodontax, containing herbal ingredients; and an 0.8 % Emser salt solution, on the growth of oral bacteria and dental plaque.. Growth of Actinomyces viscosus T14V, Capnocytophaga ochracea 25, C. sputigena 4, Actinobacillus actinomycetemcomitans (A.a.) Y4, and pooled supragingival plaque in the presence of the various mouthrinses, applied to paper discs, was tested in an agar diffusion test. In a second series of tests, the 4 bacterial strains were exposed to the agents for about 3 min to simulate rinsing, then the agent was removed, and the bacteria were inoculated into fresh nutrient broth. After 48 h bacterial growth was measured in a spectrophotometer and compared with the controls.. In the agar diffusion test only Meridol, the organic amine/stannous fluoride-containing solution, could inhibit bacterial growth, except for A. a. Y4. When the bacteria where in contact with the agents for only a few minutes these results were confirmed. Neither Paradontax nor Emser salt inhibited the growth of the bacteria, and A. a. Y4 proved to be resistant to all three agents. Growth of the other three strains was inhibited by Meridol 92-99% (undiluted), 85-96% (1:5) and 83-98% (1:10).. We conclude that only Meridol contains ingredients capable of inhibiting the growth of oral bacteria in vitro. The efficacy of the other two mouthrinses in reducing plaque accumulation in vivo has to be explained by other mechanisms.

Topics: Actinomyces; Agar; Aggregatibacter actinomycetemcomitans; Amines; Capnocytophaga; Dental Plaque; Drug Combinations; In Vitro Techniques; Mineral Waters; Mouthwashes; Oral Hygiene; Phytotherapy; Plant Extracts; Salts; Sodium Bicarbonate; Tin Fluorides

This study describes the effects of varnish containing 40% chlorhexidine diacetate on Actinomyces naeslundii populations in plaque from human molar fissures. In each of 15 subjects two dental fissures with high levels of mutants streptococci were selected. The experimental treatment consisted of the single application of a small amount of chlorhexidine varnish onto the selected fissures. The varnish was removed 15 min after application. One month after varnish application a significant increase was observed in A. naeslundii counts while the number of mutans streptococci had decreased significantly compared with preexperimental levels. From 85 randomly selected Actinomyces isolates taken from blood agar plates before varnish application, 44% belonged to A. naeslundii genospecies 1 and 56% to A. naeslundii genospecies 2. From 106 isolates taken 1 month after chlorhexidine varnish application, 42% belonged to A. naeslundii genospecies 1 and 58% to A. naeslundii genospecies 2. At baseline 28% of A. naeslundii genospecies 1 strains were catalase-positive, but 1 month after varnish application 4% of the strains were catalase-positive (p < 0.05). It is concluded that chlorhexidine varnish application caused an increase of A. naeslundii in dental plaque, but induced no significant changes in the distribution of the two A. naeslundii genospecies.

Topics: Actinomyces; Actinomyces viscosus; Adolescent; Adult; Agar; Anti-Infective Agents, Local; Catalase; Chlorhexidine; Colony Count, Microbial; Culture Media; Dental Plaque; Humans; Paint; Streptococcus; Streptococcus mutans; Streptococcus sanguis

The microbiota of root caries lesions of different grades of severity were studied. Fourteen lesions were examined. The experimental design of the study allowed correlation of histopathologically distinguishable stages with specific and distinct microbial populations. Dentin samples were ground in a sterile mortar and cultured anaerobically on nonselective Columbia blood agar plates supplemented with 5% hemolyzed human blood and on media selective for Lactobacillus spp. and streptococci. The cultivable microbiota were quantitatively speciated using Rapid ID 32A, Rapid ID 32 Strep, API 20 Strep, APIZYM, and API50 CH tests and SDS-PAG electrophoresis. In initial as well as in advanced lesions gram-positive bacteria accounted for approximately 90% of the CFUt. The proportion of Actinomyces, and in particular A. naeslundii was significantly higher (p < 0.05) in initial lesions than in advanced lesions. In contrast, the percentage of Streptococcus and especially S. mutans was higher (p < 0.05) in advanced than in initial lesions. Surprisingly low (0.8% of the CFUt) was the percentage of lactobacilli in advanced lesions. Gram-negative bacteria formed a minor part of the microbiota in both initial and advanced lesions. Among the gram-negative isolates, Prevotella, Selenomonas, and Bacteroides spp. were most noticeable. In advanced lesions, only the outermost layer of 0.5 mm thickness was populated by a high number of bacteria; the following segments harbored a negligible number of bacteria only. It is concluded that root caries is a continuous destruction process which is restricted to a subsurface zone of limited depth. The necrotic dentin is successively worn away, leading to a saucer-shaped cavitation which is repopulated by plaque. The creation of cavitations favors an aciduric flora. This might explain the succession of bacterial populations observed during the destruction process.

Topics: Actinomyces; Adult; Agar; Aged; Bacteria; Bacteroidaceae; Bacteroides; Blood; Colony Count, Microbial; Culture Media; Dental Plaque; Dentin; Disease Progression; Electrophoresis, Polyacrylamide Gel; Gram-Positive Bacteria; Humans; Lactobacillus; Middle Aged; Necrosis; Prevotella; Root Caries; Sodium Dodecyl Sulfate; Streptococcus; Streptococcus mutans

Peptostreptococcus micros, an anaerobic gram-positive coccus, has been associated with periodontal and endodontic lesions, including those refractory to treatment, as well as many human polymicrobial infections in other body locations. A selective and differential medium for the primary isolation of P. micros was developed and evaluated. Columbia CNA agar, a selective medium for gram-positive cocci, was supplemented with glutathione and lead acetate (P. micros medium: PMM). P. micros has a characteristic of rapidly utilizing the reduced form of glutathione to form hydrogen sulfide, which reacts with lead acetate producing a black precipitate in the medium. When grown on PMM, P. micros can be easily identified by its typical colonial morphology and the presence of a black precipitate directly under the colony. PMM was compared for the growth of P. micros with phenylethyl alcohol agar (PEA) and Columbia base medium (CBM) with 80 strains of P. micros and 30 strains of other gram-positive cocci. All P. micros isolates tested grew and showed the typical morphology of P. micros on PMM. Using colony counts on CBM as controls, there was an average 81.8% recovery in the number of P. micros colonies on PMM, in contrast to an average 6.1% recovery on PEA. Subgingival plaque and tongue samples from 12 adult periodontitis and 6 early-onset periodontitis patients were cultured onto PMM for the isolation of P. micros. P. micros was isolated on PMM and identified biochemically and enzymatically from both adult periodontitis and early-onset periodontitis patients with higher percentages isolated from the diseased periodontal pockets of adult periodontitis patients; furthermore, this is the first isolation of P. micros from tongue samples taken from periodontally diseased patients. This medium in cultural studies will further our understanding and assist future investigations of P. micros involved in disease processes.

Topics: Agar; Analysis of Variance; Bacteriological Techniques; Colony Count, Microbial; Culture Media; Dental Plaque; Evaluation Studies as Topic; Glutathione; Humans; Hydrogen Sulfide; Organometallic Compounds; Peptostreptococcus; Periodontitis; Sensitivity and Specificity; Staphylococcus; Statistics, Nonparametric; Streptococcus; Tongue

The effect of titanium on the growth of plaque organisms was studied in vitro. Thioglycollate broth containing either titanium or glass cylinders was inoculated with plaque micro-organisms and incubated aerobically and anaerobically at 37 degrees C for 6 hours. Growth was measured by observing an increase in turbidity of the broth. Cultures grew more vigorously aerobically than anaerobically. In the presence of titanium there was also more growth aerobically than anaerobically. There was no significant difference between the turbidity values obtained in the presence or absence of titanium suggesting that titanium does not influence the growth of plaque micro-organisms significantly.

Topics: Agar; Analysis of Variance; Bacteria, Aerobic; Bacteria, Anaerobic; Culture Media; Dental Abutments; Dental Plaque; Humans; Microbial Sensitivity Tests; Nephelometry and Turbidimetry; Surface Properties; Thioglycolates; Titanium

The purposes of this investigation were to evaluate and compare the antimicrobial effect of (1) twelve 0.4 per cent stannous fluoride (SnF2) commercial products and (2) different concentrations of SnF2 (range = 0.02 to 3.28 per cent). The antibacterial inhibitory effect of various SnF2 gels was evaluated as to their effectiveness against oral plaque bacteria including strains of S. mutans, S. sanguis, S. sobrinus, A. viscosus, A. actinomycetemcomitans, and B. intermedius. When twelve different commercial preparations of 0.4 per cent SnF2 were compared for inhibitory effect on plaque bacteria, several of the SnF2 preparations were significantly more effective in inhibiting oral bacteria (p < 0.05). With increasing concentration of SnF2, there was a comparable increase in the inhibitory effect on the oral bacteria tested (r2 ranged from 0.867 to 0.996). SnF2 at a concentration of 0.4 per cent had a similar antibacterial effect to 0.12 per cent chlorhexidine. This in vitro study demonstrated that certain SnF2 products are highly effective in inhibiting the growth of bacteria often found in plaque, and this inhibitory effect is directly related to the concentration of the SnF2.

Topics: Actinomyces viscosus; Agar; Aggregatibacter actinomycetemcomitans; Bacteria; Bacteroides; Chlorhexidine; Culture Media; Dental Plaque; Escherichia coli; Gels; Humans; Streptococcus mutans; Streptococcus sanguis; Streptococcus sobrinus; Tin Fluorides

In four young adult monkeys, periodontitis was experimentally induced by inserting elastic rubber bands around the necks of two teeth on each side of the mandible. On one side the teeth were not cleaned during the experimental period. On the control side, the teeth were cleaned by scaling and polishing weekly. After 8 weeks there were 6 mm deep pockets and great bone loss on the experimental side. Subgingival plaque was collected from experimental and control sides under anaerobic conditions and transported in a reduced transport fluid. The microorganisms were incubated anaerobically for 7 days on four different media: 1) Horse blood agar, 2) Rabbit blood agar, 3) Kanamycin-vancomycin blood agar, 4) Rabbit blood agar with Kanamycin and supernatant of filtrated Propionibacterium acnes culture (BPBSM). All media contained 0.5 microgram/ml menadione and 5.0 micrograms/ml hemin. Colony forming units of black-pigmented Bacteroides were found on all four media from all animals and were increased in numbers in the experimental side. One hundred and fifteen isolates of black-pigmented colonies were identified biochemically. Recovery of black-pigmented Bacteroides on BPBSM was significantly higher than on the other three media.

Topics: Agar; Alveolar Bone Loss; Animals; Bacteroides; Colony Count, Microbial; Dental Plaque; Dental Scaling; Female; Macaca fascicularis; Periodontitis

Topics: Agar; Colony Count, Microbial; Dental Plaque; Humans; Saliva; Streptococcus mutans

Two commercial agar media for the cultivation of anaerobes were compared with four other media for their ability to support the growth of a wide range of anaerobes from clinical specimens of subgingival plaque. Fastidious anaerobe agar (FAA, Lab M) and anaerobe agar (GAA, Gibco) allowed better growth of the pure cultures than the other media. FAA recovered the highest numbers of bacteria from subgingival plaque specimens which were composed predominantly of anaerobes. GAA performed poorly with these samples. It is concluded that FAA seemed to be superior to the other media tested for the cultivation and recovery of anaerobes.

Topics: Agar; Bacteria, Anaerobic; Culture Media; Dental Plaque

For the isolation of Streptococcus mutans, several selective media have been developed, of which Mitis-Salivarius Sucrose Bacitracin agar (MSB) is the most widely used (Gold et al., 1973). Recently, the Trypticase Yeast-Extract Cystine agar medium (TYC, de Stoppelaar et al., 1967) was modified into a selective medium for S. mutans, called Trypticase Yeast-Extract Cystine Sucrose Bacitracin (TYCSB, van Palenstein Helderman et al., 1983). The aim of this study was to compare the recovery of S. mutans from clinical samples on Mitis-Salivarius agar (MS), MSB, TYC, and TYCSB. Further, a new simple selective medium for S. mutans was introduced. This medium, called TSY20B, was supposed to have the same qualities as TYCSB, but its preparation is less laborious. One hundred eighty-five plaque and saliva samples from 37 subjects were plated on MS, MSB, TYC, and TYCSB, and 285 samples from 23 subjects were plated on TYCSB and TSY20B. All plates were incubated at 37 degrees C in a 91% N2, 5% CO2, 4% H2 atmosphere for five days. The S. mutans counts on TYC and TYCSB were significantly higher than on MS or MSB by almost a factor of 10. Seventy-seven percent of the samples gave higher S. mutans counts on TYCSB than on MSB. Especially, samples with high S. mutans d/g numbers gave lower S. mutans counts on MSB. These data clearly indicate that MSB agar is inhibitory for S. mutans and should not be used. An additional advantage of TYCSB over MSB agar is the possibility of distinguishing S. mutans serotypes d/g from other serotypes.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Agar; Bacitracin; Bacteriological Techniques; Caseins; Culture Media; Dental Plaque; Humans; Protein Hydrolysates; Saliva; Streptococcus mutans; Sucrose; Yeast, Dried

Sixty-two facultative Actinomyces strains isolated from dental plaque were tested for the production of bacteriocin-like inhibitory effects by a deferred antagonism method. When incubated anaerobically, all isolates produced identical inhibitory patterns against 15 indicator organisms, but under microaerophilic conditions, little inhibitory activity was observed. Activity was not evident after anaerobic incubation on a medium buffered by 0.5% (w/v) calcium carbonate. Gas-liquid chromatographic analyses of agar blocks removed from the inhibitory zones indicated that, compared with microaerophilic conditions, anaerobic incubation encouraged production of high concentrations of lactic and succinic acids, and the concomitant fall in the pH was probably responsible for the inhibitory effects.

Topics: Acids; Actinomyces; Agar; Bacteria; Bacteriocins; Buffers; Child; Chromatography, Gas; Dental Plaque; Humans

The role of saliva in supporting the growth of dental plaque has scarcely been investigated. We have studied the growth and recovery of micro-organisms from dental plaque samples on saliva-agar plates, prepared from filter-sterilized wax-stimulated whole saliva. Under optimal conditions, the mean recovery of plaque samples on saliva agar was about 50% (range, 22-77) of the recovery on blood agar. Addition of 2.5 mmol/L dithiothreitol (DTT) strongly facilitated filter-sterilization of saliva, but DTT concentrations higher than 1 mmol/L reduced the recovery of plaque micro-organisms on saliva agar. Catalase (100 U/ml) offered protection against the inhibitory effect of DTT. Addition of glucose (1-5 mmol/L) increased only slightly the recovery of plaque micro-organisms on saliva agar. When supragingival plaque was plated on saliva- and blood-agar plates, the composition of the microflora isolated from saliva agar strongly resembled that isolated from blood agar. The predominant species--i.e., Streptococcus and Actinomyces--all grew on saliva agar though usually in numbers somewhat lower than those on blood agar. In addition, most species normally found only in low proportions in supragingival dental plaque were also found to grow on saliva agar. Collectively, the results lead to the conclusion that the supragingival microflora can utilize saliva as a complete source of nutrients.

Topics: Actinomyces; Agar; Bacteria; Blood; Dental Plaque; Glucose; Humans; Saliva; Streptococcus

A selective medium, malachite green bacitracin agar, was developed for the isolation of Actinobacillus actinomycetemcomitans from subgingival plaque of periodontally diseased patients. The medium consisted of Trypticase soy agar 40 gm/liter, bacitracin 128 micrograms/ml, malachite green 8 micrograms/ml and 5% defibrinated sheep blood. The medium, when incubated in an atmosphere of air plus 10% CO2 for 5 days, permitted greater than 80% recovery of pure cultures of A. actinomycetemcomitans when compared with a nonselective medium. The most frequent contaminant in plaque samples from different clinical conditions was Haemophilus aphrophilus. Decomposition of H2O2 was useful in differentiating these two species. Clinical studies employing the malachite green bacitracin medium revealed a significant association between the presence of the organism, A. actinomycetemcomitans and juvenile periodontitis.

Topics: Actinobacillus; Agar; Bacitracin; Bacteriological Techniques; Culture Media; Dental Plaque; Humans; Periodontitis; Rosaniline Dyes

Streptococcus mutans is normally alpha- or gamma-hemolytic on blood agar plates. However, three recently isolated S. mutans strains were observed to elicit beta-hemolysis. The production and nature of a hemolytic substance were studied.

Topics: Agar; Anaerobiosis; Blood; Dental Plaque; Hemolysin Proteins; Hemolysis; Humans; Hydrogen-Ion Concentration; Streptococcus mutans

Strains of Neisseria sicca and N. mucosa, but not N. perflava, N. subflava, N. flava, or N. flavescens were found to grow on eosin methylene blue agar. The distribution of N. sicca on the tongue dorsum, the gingival crevice area, and the coronal surfaces of teeth of humans was determined using this medium. N. sicca averaged about 5% of the total cultivable organisms of the tongues of 14 subjects examined, but it was present in only trace quantities in dental plaque on the coronal surfaces of teeth or in the gingival crevice area.

Topics: Aerobiosis; Agar; Bacteriological Techniques; Carbon Dioxide; Dental Plaque; Gingiva; Humans; Methylene Blue; Mouth; Neisseria; Tongue; Tooth

Recoveries of Streptococcus mutans from human dental plaque were lower when plated on mitis-salivarius agar obtained from Baltimore Biological Laboratories as compared with mitis-salivarius agar obtained from Difco Laboratories. However, no difference in recoveries of established laboratory strains of S. mutans was observed between these two agar preparations.

Topics: Agar; Bacitracin; Dental Plaque; Evaluation Studies as Topic; Streptococcus; Streptococcus mutans

The ability of Streptococcus mutans to grow on mitis-salivarius (MS) agar, MC agar, mitis-sucrose-bacitracin (MSB), BCY agar, and MM10 sucrose agar was studied. Batch cultures of S. mutans serotype a demonstrated no growth on MSB agar. Certain serotype d and g strains did not grow on MC agar. The yield for most strains of other serotypes on these selective media was lower compared with that on MS agar. The number of total colony-forming units on BCY and MM10 sucrose agar was similar to the blood agar results. Similar data were obtained when fermenter-grown strains, harvested in the middle or the end of the logarithmic growth phase, were used for inoculation of the various media. Enumeration of S. mutans from plaque samples plated on MC and MSB agar yielded about 75% of the counts obtained on MS or the nonselective medium. When the proportions of S. mutans were expressed as a percentage of the total cultivable flora, the selective media (MC and MSB agar) showed approximately 10% lower values than the MS, BCY, and MM10 sucrose agar.

Topics: Agar; Bacitracin; Blood; Culture Media; Dental Plaque; Streptococcus; Streptococcus mutans; Sucrose

The possible qualitative and/or quantitative alterations in the proportions of cultivable groups of oral microorganisms were analysed during a clinical trial involving the consumption of fructose (F) or xylitol (X) in comparison to sucrose (S). Supragingival plaque samples and paraffin-stimulated saliva were collected from 115 subjects. The samples were dispersed by sonication, diluted stepwise, plated on blood sugar, Mac Leod agar, Mac Concey agar, Rogosa S.L. agar, and Sabouraud agar plates and incubated anerobically and/or aerobically. The number of the total colony forming units (CFU) on blood agar plates in anaerobic incubation was about 1-3 X 10(9)/ml saliva and 1-4 X 10(8)/mg plaque and in aerobic respectively 5-18 X 10(8)/ml saliva and 10(8)/mg plaque. The total CFU on Mac Leod agar was of a similar order of magnitude. The variation between subjects and consecutive determinations was of a similar order of magnitude. The variation between subjects and consecutive determinations was relatively large. The arithmetic mean of the total CFU on Mac Concey agar was about 1-5 X 10(5)/ml saliva, on Rogosa S.L. agar 6-130 X 10(3)/ml saliva and on Sabouraud about 1-2 X 10(3)ml saliva, all in aerobic incubations. Replacement of dietary sucrose with xylitol did not affect the proportion of major microbial categories in saliva or dental plaque. The percentage of typical streptococcal colonies on blood agar was of a similar order of magnitude (about 60-70%) during the diets. The arithmetic and geometric means of the total CFU values on Rogosa and Sabouraud agar plates were significantly lower in the X-group than in the S- or F-groups after a diet period of some months. It was thought that the reason for the reduction of acidogenic and aciduric oral flora in the X-group was partly due to the fact that xylitol is generally not metabolized by these microorganisms.

Topics: Agar; Cell Division; Culture Media; Dental Plaque; Diet, Cariogenic; Fructose; Humans; Saliva; Specimen Handling; Sucrose; Xylitol

Several Streptococcus mutans strains were markedly inhibited by mitis-salivarius agar manufactured by Baltimore Biological Laboratories, but little, if any, inhibition was noted using Difco Laboratories' mitis-salivarius agar. Supplementation of the basic medium with sucrose and bacitracin for specific selection of S. mutans resulted in suppression of representative S. mutans type a strains regardless of manufacturer.

Topics: Agar; Bacitracin; Child; Dental Caries; Dental Plaque; Humans; Streptococcus; Streptococcus mutans; Sucrose

Incorporation of the antibiotic polymixin B sulfate in plates of Mitis-Salivarius medium at a level of 100 U per ml effectively suppressed the growth of gram-negative spreading organisms which occasionally overgrow Mitis-Salivarius plates of oral samples and make them unsuitable for enumeration and differentiation of streptococci. At the indicated level the antibiotic did not affect the growth or typical colonial characteristics of the oral streptococci.

Topics: Agar; Bacteria; Chile; Dental Plaque; Ecuador; Evaluation Studies as Topic; Florida; Humans; Polymyxins; Puerto Rico; Socioeconomic Factors; Streptococcus; Streptococcus mutans

Five agar media in combination with the Hungate roll tube technique and conventional anaerobic jar technique (Baird & Tatlock¿ jars) were evaluated to determine the most suitable medium for non-selective isolation of the viable microorganisms in dental plaque. The highest colony count was obtained by using "Modified Medium 10" with the roll tube technique. About twice as many plaque colonies were recovered by roll tube technique as by the conventional anaerobic technique. With the MM 10 roll tube technique, 7 d of incubation revealed only 93% of the colonies that could be detected after 14 d of incubation.

Topics: Adult; Agar; Aged; Bacteria; Bacteriological Techniques; Culture Media; Dental Plaque; Female; Humans; Male; Middle Aged; Time Factors

Topics: Agar; Animals; Antigens, Bacterial; Blood; Cricetinae; Cross Reactions; Culture Media; Dental Caries; Dental Plaque; Dextrans; Endocarditis, Subacute Bacterial; Fluorescent Antibody Technique; Hemolysis; Humans; Immune Sera; Precipitin Tests; Rabbits; Rats; Serotyping; Streptococcus

Topics: Agar; Bacitracin; Cell Count; Culture Media; Dental Plaque; Humans; Streptococcus; Sucrose

Topics: Adhesiveness; Agar; Composite Resins; Culture Media; Dental Amalgam; Dental Plaque; Humans; Models, Biological; Polystyrenes; Silicate Cement; Solutions; Streptococcus; Sucrose; Time Factors

An enriched nutrient agar medium containing blue dextran has been utilized for the detection of dextranase-producing microorganisms in human dental plaque. When compared with the total viable anaerobic plaque flora, the proportion of these microbes in supragingival plaque from different individuals varied over a wide range. Preliminary characterization of some of the dextranase-producing microorganisms revealed a heterogeneous mixture of cell types with varying morphological and biochemical characteristics. Several bacterial isolates were tentatively identified as being members of the genus Actinomyces. An additional isolate appeared to belong to the genus Bacteroides. The dextran-degrading enzymes produced by these bacteria are extracellular, and a cell-free preparation from one of the isolates has been shown to cause extensive endohydrolytic cleavage of high-molecular-weight dextrans.

Topics: Actinomyces; Agar; Anaerobiosis; Bacteriological Techniques; Bacteroides; Cell-Free System; Chromatography; Dental Plaque; Dextranase; Dextrans; Humans; Hydrolysis

Topics: Agar; Cell Count; Culture Media; Dental Plaque; History, Modern 1601-; Streptococcus

Topics: Agar; Culture Media; Dental Plaque; Humans; Streptococcus; Sucrose

Dental plaque samples from (i) subjects with no apparent oral disease, (ii) mentally retarded subjects with periodontal disease, and (iii) subjects with active caries were collected in three transport media viz. a dithiothreitol poised balanced mineral salt solution designated as reduced transport fluid (RTF), VMG II, and modified Stuart medium (SBL). The samples were dispersed by sonic treatment, diluted in the respective medium in which they were collected, and cultured on MM10 sucrose agar. The efficiency of the transport media in the survival of dental plaque flora was determined by comparing the quantitative recovery (expressed as percentage of the initial viable count) from the specimens stored for various lengths of time. The data showed a great variation in the recovery of the oral bacterial flora from the plaque samples. VMG II and SBL served better than RTF as storage media for non-disease-associated dental plaque cultured under strict anaerobic conditions. Recoveries of bacteria from periodontal plaque specimens stored in RTF were higher than SBL and VMG II under identical conditions. The organisms present in the carious plaque samples appeared to survive much better in RTF and VMG II than in SBL as determined by conventional anaerobic culturing technique. However, VMG II showed a higher recovery of organisms from these specimens with an increase in the storage period, suggesting multiplication of the plaque flora. RTF did not allow the growth of oral bacterial flora under all experimental conditions. On the basis of the relative performance of these media it is suggested that RTF is a satisfactory medium for the transport of oral bacteria present in the samples.

Topics: Adult; Agar; Anaerobiosis; Bacteria; Bacteriological Techniques; Cell Count; Cell Survival; Child; Culture Media; Dental Caries; Dental Plaque; Dithiothreitol; Edetic Acid; Humans; Periodontal Diseases; Preservation, Biological; Specimen Handling; Streptococcus; Sucrose

Topics: Agar; Apatites; Calcium; Calcium Phosphates; Child; Culture Media; Dental Caries; Dental Plaque; Glucose; Humans; Hydrogen-Ion Concentration; Statistics as Topic; Streptococcus; Tooth