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Biomedical subjects

S S Socransky

Publications and source records attributed to S S Socransky.

At least 181 records · Page 10Linked to original sources

Concentration of tetracycline in human gingival fluid after single doses.

The concentration of tetracycline in gingival fluid was measured following the oral administration of single doses of 250 or 500 mg. Six volunteers received a single dose of either 250 mg or 500 mg of tetracycline and gingival fluid was sampled at 15-min intervals during the first 2 h, 30-min intervals for the following 2 h and at hours 5, 6 and 7. Four volunteers were given a single dose of either 250 mg or 500 mg and were sampled every hour for 24 h. Gingival fluid was sampled using an intracrevicular technique from four gingival sites and blood was obtained by finger puncture. The concentration of tetracycline in gingival fluid peaked at 3 1/2-7 h achieving average levels typically in the range of 5-12 micrograms/ml. Blood levels peaked at 3-4 h and reached values between 1.0 to 2.6 micrograms/ml. Tetracycline was detectable in gingival fluid at least 19 h after a single dose but rarely was detectable at 24 h. The results demonstrated that tetracycline in the gingival fluid was typically 2-10 times blood levels after a single dose.

Gingival Crevicular Fluid↗

Comparison of three anaerobic culture techniques amd media for viable recovery of subgingival plaque bacteria.

Various methods are available for viable recovery of bacteria from subgingival plaque, but their relative efficiency is not clear. In the first experiment, with 10 patients, three anaerobic techniques (Brewer jars, chamber and role tubes) and three agar media (trypticase soy with 5% sheep blood (TS), brucella agar with 5% blood and 0.5 microgram/ml of menadione (B), and modified medium 10 with 3% blood (MM 10) were compared. In the second experiment, with another 10 patients, Brewer jars were compared with a glove box, using TS. Subgingival plaque was sampled with a gas flushed broach passed through a syringe. Significance of differences in viable recoveries was determined by ANOVA. Brewer jars and chamber (aerobic plating) were comparable in efficiency, but excelled roll tubes (anaerobic inoculation). TS was better than B, but equivalent to MM 10. TS in Brewer jars (aerobic plating) matched TS in the glove box (anaerobic plating), but performed better than all the other procedures tested. Recoveries did not differ on pre- and non-prereduced plates and on commercial and laboratory, freshly made plates. Non-evacuated jars sealed inside the box (anaerobic plating) provided lower recoveries than jars evacuated, filled and sealed outside (aerobic plating). Roll tubes benefited most by extending incubation from 7 to 14d. Commercial, non-prereduced TS agar plates incubated in Brewer jars of a glove; box are highly recommendable methods for processing of subgingival plaque.

Adolescent↗

Ultrasonic dispersion of pure cultures of plaque bacteria and plaque.

This study compared the sonic sensitivity of 12 Gram-negative and two Gram-positive bacteria commonly encountered in plaque associated with periodontal diseases. Pure bacterial cultures were grown to standard turbidity, diluted in 1/4 strength prereduced anaerobically sterilized Ringer's solution, and aliquots dispersed for 0-180 s, using an MSE sonic oscillator at 6 micron under 80% N2, 10% H2 and 10% CO2. Viable recoveries were determined on anaerobically cultured trypticase soy 5% blood agar plates. Breakage of T. denticola was assessed by electron microscopy. Gram-positive organisms tolerated sonication better than Gram-negative. A. viscous was more resistant than Strep sanguis. Gram-negative bacteria could be divided into groups according to their sensitivity. Eikenella corrodens was most resistant, followed by F. nucleatum B asaccharolyticus, Capnocytophaga gingivalis, A actinomycetemcomitans, a strain (2097) of Group IV Bacteroides, and B melaninogenicus ss intermedius resisted sonication better than "corroding' Bacteroides and oral Campylobacter. T. denticola, Selenomonas sputigena and Wolinella were most sensitive with viable counts which declined after sonication for 5-10 s. Recoveries from plaque taken from five patients with periodontal diseases increased with sonication time, reaching higher values for suprangingival than for subgingival samples.

Actinomyces↗

Gingival crevicular fluid levels of clindamycin compared with its minimal inhibitory concentrations for periodontal bacteria.

Clindamycin concentrations in gingival crevicular fluid and in blood were determined over a 7-h period and were related to the minimal inhibitory concentrations of this agent for 340 bacterial strains isolated from diseased periodontal sites. The clindamycin levels after administration of single 300-mg oral doses were measured in gingival crevicular fluids by using an agar diffusion bioassay. Minimal inhibitory concentrations were determined by agar dilution techniques for 30 species of periodontal bacteria. With the exception of Eikenella corrodens and Actinobacillus actinomycetemcomitans, most of the bacteria were inhibited by a concentration of 1.0 microgram of clindamycin per ml or less. The peak concentrations in crevicular fluid (2.0 +/- 0.3 microgram/ml) and in blood (1.9 +/- 0.3 micrograms/ml) were approximately the same. However, crevicular fluid levels of 1.0 micrograms/ml and above were present for up to 6 h, whereas blood concentrations dropped below 1.0 micrograms/ml within 2 h after administration. Based on its minimal inhibitory concentrations, clindamycin at crevicular fluid levels of 1.0 micrograms/ml or above should inhibit most bacteria associated with diseased periodontal sites.

Bacteria↗

A selective medium for Actinobacillus actinomycetemcomitans and the incidence of the organism in juvenile periodontitis.

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.

Actinobacillus↗

Tetracycline: levels achievable in gingival crevice fluid and in vitro effect on subgingival organisms. Part I. Concentrations in crevicular fluid after repeated doses.

The concentration of tetracycline in gingival crevice fluid and blood was determined using a sensitive bioassay after oral administration of repeated doses of tetracycline. Crevicular fluid was sampled by an intracrevicular technique from four gingival sites in each individual and blood was obtained by finger puncture. Four volunteers received doses of 250 mg of tetracycline-HCl either every 6 hours or every 12 hours and were sampled at hours 0 to 15, 21 to 36, 48 to 60 and 96 to 102. Volunteers given 250 mg every 6 hours had average crevicular fluid concentrations between 4 to 8 micrograms/ml and blood concentrations between 2 to 2.5 micrograms/ml after 48 hours. The levels in crevicular fluid and blood of volunteers who received 250 mg every 12 hours were 2 to 4 micrograms/ml and 0.3 to 1.4 micrograms/ml respectively after 48 hours. The results demonstrated that after repeated doses of tetracycline the crevicular fluid levels were typically 2 to 4 times the blood levels.

Administration, Oral↗

Tetracycline: levels of achievable in gingival crevice fluid and in vitro effect on subgingival organisms. Part II. Susceptibilities of periodontal bacteria.

The sensitivity to tetracycline of 345 bacterial isolates from periodontal lesions was determined. Most species of bacteria, including those thought to be involved in the initiation and progress of destructive periodontal disease, were inhibited in vitro by tetracycline concentrations of 4 to 8 micrograms/ml. This concentration is equivalent to crevicular fluid levels of tetracycline at dosages of 1 gm/day. These data indicate that tetracycline is inhibitory at levels achieved in crevicular fluid for bacteria currently implicated in destructive periodontal disease.

Bacteria↗

Sensitive assay for measuring tetracycline levels in gingival crevice fluid.

An increased interest in the clinical use of antibiotics as an adjunct to periodontal therapy has created a need to determine antibiotic concentrations in fluid obtained from the gingival crevice. For this purpose, an increase in sensitivity beyond that possible with current tetracycline assays is essential because sample volumes of gingival fluid typically obtained are less than 0.5 microliter. This report describes the development of an agar-diffusion assay technique capable of measuring the concentration of tetracycline in samples of gingival crevice fluid in the range of 0.1 to 4.0 microgram/ml. The assay will detect amounts of tetracycline in gingival crevice fluid samples as low as 50 pg. The high sensitivity of this assay was achieved by optimizing the medium depth, inoculum density, agar concentration, pH, period of prediffusion, and selection of basal medium. Use of this assay indicated that the concentration of tetracylcine in gingival crevice fluid was greater than that found in blood and persisted at elevated levels for longer periods.

Biological Assay↗

Morphology and ultrastructure of oral strains of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus.

Selected human oral and nonoral strains of the genera Actinobacillus and Haemophilus were examined by transmission and scanning electron microscopy. The strains examined were morphologically identical to recognized Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, and Haemophilus paraphrophilus. By transmission electron microscopy, the cells were typically gram negative in morphology, with several strains possessing some extracellular ruthenium red-staining polymeric material. Numerous vesicular structures, morphologically identical to lipopolysaccharide vesicles, were seen to originate from and be continuous with the surface of the outer membrane. Large numbers of these vesicles were also found in the external environment. Scanning electron microscopic observations revealed that both actinobacilli and haemophili possessed surface projections and an amorphous surface material which connected and covered adjacent cells.

Actinobacillus↗

Cellular fatty acid composition of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus.

Strains of Actinobacillus actinomycetemcomitans isolated from deep pockets of patients with juvenile periodontitis were analyzed for their content of cellular fatty acids. Oral Haemophilus strains, morphologically and biochemically similar to Haemophilus aphrophilus, were also examined for their content of cellular fatty acids. The extractable lipids of the actinobacilli represented approximately 10% of the cell dry weight, with the bound lipids representing 2 to 5%. The major fatty acids consisted of myristic (C14:0) and palmitic (C16:0) acids and a C16:1 acid, possibly palmitoleic acid, accounting for 21, 35, and 31% of the total extractable fatty acids, respectively. Haemophilus strains had a similar cellular fatty acid content.

Actinobacillus↗

A neutrophil disorder induced by capnocytophaga, a dental micro-organism.

We recovered capnocytophaga, a gram-negative anaerobe implicated in the pathogenesis of periodontal disease, from two patients with a history of dental infections. Neutrophils from both patients failed to acquire the asymmetric shape characteristic of normal neutrophils. Fluorescein staining of the patients' living neutrophils remained diffuse and patchy instead of showing the normal pattern in which the fluorescence is swept into the rear of the cell. The locomotion of one patient's neutrophils in vitro was less than 50 per cent of that of normal neutrophils, and migration of this patient's neutrophils into dermal abrasions was reduced, although phagocytosis and nitroblue tetrazolium reduction were normal. All abnormalities of neutrophil morphology and function disappeared after eradication of the capnocytophaga infections. Sonicates and culture medium of capnocytophaga contained a dialyzable substance that caused normal neutrophils to behave like neutrophils obtained from the infected patients.

Adolescent↗

Capnocytophaga: new genus of gram-negative gliding bacteria. I. General characteristics, taxonomic considerations and significance.

The characteristics of gliding bacteria isolated from both healthy and diseased sites in the oral cavity are, summarized and the taxonomic position of the bacteria discussed. Uniform attirubtes of the fusiform isolates include gliding motility, strictly fermentative metabolism dependent on the presence of CO2 (or HCO3-), under either anaerobic or aerobic conditions, presence of benzidine-reactive components, and the production of acetic and succinic acids as the major or sole, acidic, metabolic and products. Given the guanine and cytosine content of DNA, their gliding motility, and the ability of many strains to attack polysaccharide a relationship to the cytophagus is suggested. This relationship, along with the CO2-dependent growth is recognized by the generic name Capnocytophaga given them. Many of the isolates are grouped into three species C. ochracea, C. Sputigena, and C. gingivalis, separated on the basis of morphological and physiological traits.

Adult↗

Capnocytophaga: new genus of gram-negative gliding bacteria. II. Morphology and ultrastructure.

Gram-negative, anaerobic gliding bacteria were isolated from normal supragingival plaque and from periodontal lesions. Isolates could be divided into two size classes: small 2.4-4.2 micrograms x 0.38-0.5 microgram and large 4.8-5.8 micrograms x 0.42-0.6 microgram cells. The outer membrane was either loose-fitting and wavy, or taut, and of variable thickness. An electron-dense fuzz was discernible on several of the isolates. The periplasmic region was of variable electron-density. The genus Capnocytophaga has been proposed for these organisms based on morphological and cultural characteristics.

Adult↗

Capnocytophaga: new genus of gram-negative gliding bacteria. III. Physiological characterization.

Sixty-eight strains of capnophilic fusiform Gram-negative rods from the human oral cavity were subjected to extensive physiologic characterization, tested for susceptibility to various antibiotics, and the mol-percent guanine plus cytosine of each isolate determined. The characteristics of the isolates were compared with 10 fresh and 2 stock isolates of Fusobacterium nucleatum. The isolates clearly differed from the Fusobacterium species on the basis of mol-percent guanine plus cytosine, end products, growth in a capnophilic environment and fermentation of carbohydrates. All of the gliding isolates required CO2 and formed acetate and succinate, but not H2S, indole or acetylmethylcarbinol. All fermented glucose, sucrose, maltose and mannose. The organisms may be differentiated on the basis of fermentation of additional carbohydrates, hydrolysis of polymers and reduction nitrate. Three species are proposed: Capnocytophaga ochracea, Capnocytophaga sputigena and Capnocytophaga gingivalis. Ten isolates did not fit into the proposed species.

Adult↗

Jawbone cavities and trigeminal and atypical facial neuralgias.

The possible role of dental and oral disease in the etiology of idiopathic trigeminal and atypical facial neuralgias has been examined. Among thirty-eight patients with idiopathic trigeminal neuralgia and twenty-three patients with atypical facial neuralgia, there was in nearly all instances a close relationship between pain experienced and the existence of cavities in alveolar bone and jawbone of the patients. The cavities were at the sites of previous tooth extractions and, although at times more than 1 cm. in a given diameter, were usually not detectable by x-rays. A new method for their detection and localization was developed empirically, based on the observation that peripheral infiltration of local anesthetic into or very close to the bone cavity rapidly abolished trigger and pain perception by patients during persistence of the anesthetic action. Histopathologic examination of bone removed from cavities by curettage revealed, in both idiopathic trigeminal and atypical facial neuralgias, a similar pattern characterized by a highly vascular abnormal healing response of bone. Some lesions presented a mild chronic inflammatory (lymphocytic) infiltration. Preliminary microbiologic studies of material from the walls of the cavities showed the existence within them of a complex, mixed polymicrobial aerobic and anaerobic flora. Treatment consisted of vigorous curettage of the bone cavities, repeated if necessary, plus administration of antibiotics to induce healing and filling-in of the cavities by new bone. Responses of patients to the above treatment consisted of marked to complete pain remissions, the longest of which has been for 9 years. Complete healing leads to complete and persistent pain remissions. It was concluded that in both idiopathic trigeminal and atypical facial neuralgias, dental and oral pathoses may be major etiologic factors.

Adult↗