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Biomedical subjects

J Slots

Publications and source records attributed to J Slots.

At least 127 records · Page 7Linked to original sources
PubMed1993

Comparison of two pressure-sensitive periodontal probes and a manual periodontal probe in shallow and deep pockets.

Three periodontal probes--a manual probe and two computerized, pressure-sensitive probes--were studied to determine their relative recording accuracy. In the first part of the study, replicate probing measurements were taken with the three probes at shallow (less than 5 mm) and deeper (greater than or equal to 5 mm) periodontal sites. In the second part of the study, probing depths were determined on all teeth except third molars by the three probing techniques at a single appointment. Mean values between replicate probings for each instrument did not differ statistically, except for duplicate measurements with one of the electronic probes in pockets with depths greater than 5 mm. All three probes demonstrated higher standard deviations with increasing depth, which indicates decreased reproducibility of probing depth measurements. Results of this study suggest that an electronic, pressure-sensitive probe yields more reproducible probing depth measurements than a conventional manual periodontal probe.

Adult↗
PubMed1993

The current status and future prospects of altering the pathogenic microflora of periodontal disease.

Modern periodontal therapy aims to suppress or eradicate periodontal pathogens and to maintain a posttreatment flora that is compatible with health. Systemic and local antimicrobial therapies have demonstrated effectiveness against several periodontal pathogens. Sustained-release devices, or irrigators, for local application of antimicrobial agents to periodontal pockets show great promise. Replacement therapy and periodontal vaccines, although still in the early research phase, represent very interesting approaches for preventing periodontitis. Using modern molecular genetic methods, it is theoretically possible to clone virulence determinants of periodontal pathogens into a nonpathogenic organism. The carrier organism with the expressed foreign antigens may be implanted in the oral cavity or the intestinal tract to induce long-lasting immunity against the targeted periodontal pathogens.

Anti-Bacterial Agents↗
PubMed1993

Antimicrobial therapy in periodontics.

Cause-related therapy in periodontics is aimed at the reduction or elimination of microbial pathogens. Periodontitis is associated with microflorae which may consist of indigenous, exogenous or superinfecting organisms. In general, periodontal infections due to indigenous organisms (endogenous or commensal infections) are treated by continual reduction of the bacterial load, exogenous infections (true infections) by adjunctive antibiotic therapy and superinfections (opportunistic infections) by a combined approach of conventional therapy and improvement of compromising host or environmental factors. Properly selected single drug, combination drug and serial drug therapies show great promise in the treatment of severe periodontitis

Amoxicillin↗
PubMed1992

Peptostreptococcus micros in human periodontitis.

Peptostreptococcus micros is a recognized pathogen in medical infections, and its association with progressive periodontitis was examined in this study. P. micros was isolated from paper-point subgingival samples on anaerobic enriched blood agar plates and identified on the basis of cellular and colonial morphology and selected biochemical tests. In a cross-sectional study involving 907 people with advanced adult periodontitis, 127 with early-onset periodontitis, and 12 with localized juvenile periodontitis, P. micros in these patient groups occurred with a prevalence of 58-63%. In culture-positive patients, P. micros averaged 12-15% of total viable counts. P. micros demonstrated similar occurrence and proportional recovery in all age groups. In a longitudinal study of 91 adult periodontitis patients on maintenance therapy, P. micros demonstrated a significantly higher prevalence in disease-active than in disease-inactive patients (47% vs 14%). Mechanical subgingival debridement and 0.12% chlorhexidine pocket irrigation was unable to eradicate subgingival P. micros from 18 of 22 adult periodontitis patients. In vitro antimicrobial susceptibility testing showed P. micros to be sensitive to therapeutic levels of penicillin, clindamycin and metronidazole. Our findings indicate that P. micros is a potential pathogen in adult periodontitis. The methods for its eradication from subgingival sites remain to be determined.

Adult↗
PubMed1992

Enterococci in human periodontitis.

Enterococci are potential pathogens in many human body sites. This study determined the subgingival occurrence and the in vitro antimicrobial susceptibility of enterococci in 100 persons with early-onset periodontitis and 545 persons with advanced adult periodontitis. Subgingival microbial samples were collected with paper points, transported in VMGA III and plated onto anaerobic enriched brucella blood agar or selective Enterococcosel agar (BBL Microbiology Systems). Enterococcal speciation was performed using commercial micromethod kit systems. In vitro sensitivity was determined using a commercial kit system and an agar dilution assay. Subgingival enterococci occurred in 1% of early-onset periodontitis patients and in approximately 5% of adult periodontitis patients. Enterococcus faecalis was the only enterococcal species recovered, and all but one isolate belonged to the same biotype. In vitro antimicrobial sensitivity testing revealed subgingival enterococci resistant to therapeutic levels of penicillin G, tetracycline, clindamycin and metronidazole, but relatively sensitive to ciprofloxacin and amoxicillin/potassium clavulanate (Augmentin). Enterococci may populate periodontal pockets as superinfecting organisms and, in heavily infected patients, may contribute to periodontal breakdown.

Adult↗
PubMed1992

Evaluation of a non-radioactive DNA probe for detecting Porphyromonas gingivalis in subgingival specimens.

This study compared the ability of a nonradioactive digoxigenin-labeled DNA probe and anaerobic culture to identify subgingival Porphyromonas gingivalis. Total cellular DNA from P. gingivalis ATCC 33277T was labeled using the Genius kit from Boehringer Mannheim Biochemicals. Anaerobic culture was performed using VMGA III transport medium and enriched brucella blood agar. The DNA probe could detect as little as 1000 P. gingivalis cells added to supragingival plaque. Also, the probe could detect P. gingivalis when it was present in proportions too low to be visualized on overgrown bacterial plates. The probe showed no visible reaction with strains of various oral species or with thousands of non-P. gingivalis colonies from plaque samples. VMGA III could maintain the viability of P. gingivalis for up to 6 days, as evidenced by DNA probing of colony blot of subgingival cultures. A total cellular DNA probe for detecting P. gingivalis seems to offer a simple and reliable method of detecting the organism in subgingival specimens.

Colony Count, Microbial↗
PubMed1992

Wolinella recta in adult gingivitis and periodontitis.

Wolinella recta has been associated with adult periodontitis, but its role in the disease remains uncertain. This report clarifies the distribution of W. recta in periodontally healthy and diseased subjects, and treated patients with recurrent disease. A specific polyclonal rabbit antiserum against W. recta strain 372 was used for indirect immunofluorescence localization of W. recta in dental plaque from untreated and treated patients. Supragingival plaque was collected from 15 periodontally healthy individuals (H), 10 adults with mild gingivitis (G1), 8 with severe gingivitis (G2) and 15 with periodontitis (AP). Subgingival samples from 23 diseased sites (G2 and AP) were examined as well. There was a significant difference (p = 0.000) between the proportions of W. recta in subgingival (4.4%) vs. supragingival (0.3%) plaque samples from AP. A significant difference (p = 0.000) in W. recta proportions was also detected between subgingival plaque samples of AP (4.4%) vs. G2 (1.2%). No significant difference in the mean % of W. recta was found between supragingival plaque of AP (0.3%) and G2 (0%), and samples of G1 (0.01%) and H (0.1%). In a separate study, 85 adults previously treated for moderate to severe adult periodontitis were monitored over a 12-month period for evidence of disease recurrence. Recurrent disease was detected at 32 sites in 18 subjects. Of these, 20 sites in 13 subjects were positive for W. recta. With subjects as the experimental unit, a significant increase in the proportions of W. recta was found at sites with recurrent disease (3.12%) as compared to stable, paired control sites (0.24%), but only when sites with breakdown and positive for W. recta were compared with their controls. These results indicate that W. recta is associated with some, but not all sites with advanced adult periodontitis. The association of W. recta with gingivitis was not statistically significant.

Adult↗
PubMed1991

In vitro activity of chlorhexidine against enteric rods, pseudomonads and acinetobacter from human periodontitis.

Fifty-eight periodontal isolates of the families Enterobacteriaceae and Pseudomonadaceae, and the genera Acinetobacter and Achromobacter were studied to determine their susceptibility to Peridex (0.12% chlorhexidine digluconate solution; Procter & Gamble). In an agar dilution assay, about 50% of the study strains grew in the presence of 70 micrograms/ml of chlorhexidine. Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Pseudomonas cepacia, and Serratia marcescens comprised the most resistant species. Studies are needed to determine the microbiological and clinical effects of chlorhexidine usage in patients infected with enteric rods and pseudomonads.

Acinetobacter↗
PubMed1991

Distribution of Actinobacillus actinomycetemcomitans serotypes in periodontal health and disease.

A total of 177 Actinobacillus actinomycetemcomitans isolates from 136 periodontally healthy or diseased subjects were serotyped by indirect immunofluorescence and/or immunodiffusion assays. Serotype-specific rabbit antisera against A. actinomycetemcomitans serotypes a, b and c were used. All 3 serotypes were commonly found in the study subjects. Serotype b was dominant in subjects with periodontal disease and serotype c was the most common serotype in the healthy subjects. In the immunofluorescence assay, when 85 isolates were cultured anaerobically and fixed in acetone, or cultured aerobically in 10% CO2 and heat-fixed, 60 isolates revealed the same serotypes. The remaining 25 isolates reacted with 2 of the serotype-determining reagents. In the immunodiffusion assay, 22 of these 25 isolates reacted with one antiserum only. These results suggest differences in the distribution of A. actinomycetemcomitans serotypes between periodontal health and disease and point to possible variation in serotype determination due to bacterial growth and preparation procedures.

Adolescent↗
PubMed1991

Candida biotypes in human adult periodontitis.

Fifty-five Candida isolates from human periodontal pockets were biotyped using the API 20C micromethod kit system. Candida albicans (11 biotypes) constituted 81.8% of all yeast isolates. A single biotype accounted for 57.8% of the subgingival C. albicans strains. The biotype distribution of C. albicans in human periodontal pockets appears to follow a selectivity pattern similar to that of other oral surfaces.

Adult↗
PubMed1991

New views on periodontal microbiota in special patient categories.

The microorganisms in periodontitis of special patient categories have been only partially elucidated. The periodontitis microbiota of HIV-infected individuals, cancer patients on myelosuppressive therapy, and persons with other medical disorders includes common suspected periodontal pathogens as well as enteric rods, pseudomonads, staphylococci and yeasts. Failing implants also may be associated with classical periodontal pathogens as well as primarily nonoral potential pathogens. Refractory periodontitis in systemically healthy adults can show a great variety of oral and nonoral organisms. The frequent occurrence of unusual periodontal organisms in special patient categories may be due to a weakened host response and/or usage of various chemotherapeutic regimens. The unusual organisms may contribute to progressive periodontitis and in leukemia patients may even give rise to life-threatening systemic manifestations. The primary therapeutic goal in special periodontitis patients is control of pathogens and amid the wide range of pathogenic microfloras, an effective treatment strategy should include a comprehensive microbiological analysis, especially if systemic antimicrobial therapy is contemplated.

Bacteria↗
PubMed1991

Immunosuppressive effects of Prevotella intermedia on in vitro human lymphocyte activation.

In this study, we have assessed four strains of Prevotella intermedia, isolated from periodontally involved lesions, for their ability to inhibit lymphocyte functions. All four strains were found to cause a dose-dependent inhibition of B- and T-cell proliferation in response to mitogens and antigens. This was reflected in altered DNA, RNA, and protein syntheses. Furthermore, P. intermedia appeared to affect the early stages of cell activation. This was ascertained by kinetic analysis in which it was determined that the extract had to be present during the first 24 h of incubation to cause suppression. Moreover, direct assessment of the early stages of cell activation indicated that release of cytokines and expression of the interleukin 2 receptor and CD69 on T cells were inhibited by P. intermedia sonic extracts. Finally, preliminary characterization of the immunosuppressive agent indicates that it has a molecular mass of approximately 50 kDa and is heat labile. It has been proposed that impaired host defense may play a pivotal role in the pathogenesis of many infections. The data presented in this paper suggest that microbially mediated immunosuppression may contribute to the pathogenesis of periodontal disease by altering the nature and consequences of host-parasite interactions.

Bacteroides↗
PubMed1991

Microbiological study of HIV-related periodontitis.

The subgingival microbiota in 14 persons with HIV-periodontitis was examined. Subgingival plaque samples were collected with paper points, transported in VMGA III, and plated on anaerobic enriched brucella blood agar and various selective media. HIV-periodontitis sites revealed Actinobacillus actinomycetemcomitans, Wolinella recta, Peptostreptococcus micros, and Bacteroides intermedius, each averaging 7% to 16% of the cultivable subgingival flora in positive patients. High levels of spirochetes also were detected in diseased sites with phase-contrast microscopy. Low levels of Candida albicans or enteric Gram-negative rods were recovered in the subgingival flora in 7 HIV-periodontitis patients or Bacteroides fragilis, Fusobacterium necrophorum, Fusobacterium varium, and Eubacterium aerofaciens were recovered in 8 patients. These findings suggest that the major components of the subgingival microbial flora in HIV-periodontitis are similar to those associated with adult periodontitis in systemically healthy persons. However, HIV-periodontitis lesions also may contain organisms which are rarely found in common types of periodontitis. The etiological significance of specific periodontal organisms in HIV-periodontitis awaits further longitudinal study.

AIDS-Related Complex↗
PubMed1991

Antibiotic prophylaxis for medical-risk patients.

The three current regimens for the prevention of infective endocarditis are discussed and compared along, with at-risk patients and dentally-induced bacteremias. The principles of antibiotic prophylaxis, and other medical conditions where antibiotic prophylaxis is controversial or inadequately documented is critically analyzed.

Anti-Bacterial Agents↗
PubMed1991

Incidence of periodontitis recurrence in treated patients with and without cultivable Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Porphyromonas gingivalis: a prospective study.

A total of 98 adults previously treated for moderate to advanced periodontitis and on a trimonthly recall schedule were screened for the presence of critical levels of Actinobacillus actinomycetemcomitans, Prevotella (Bacteroides) intermedia, and Porphyromonas (Bacteroides) gingivalis. Patients with at least 2 positive sites were placed in a positive group and patients without or with low levels of these bacteria in a negative group. During the 30-month study the incidence of disease recurrence was greater in the positive group, but did not reach statistical significance. Positive patients with deeper pockets tended to be at greater risk of developing recurrent disease than those with shallower pockets. In the positive group only, both A. actinomycetemcomitans recovery and antibody levels to A. actinomycetemcomitans strain NCTC 9710 (serotype c) were inversely correlated with disease recurrence. The presence of A. actinomycetemcomitans and P. intermedia above critical levels did not reliably predict future episodes of disease recurrence in this population. The sparse recovery of P. gingivalis did not permit us to assess its diagnostic value. With the exception of P. gingivalis, for which insufficient data were available, the results indicate that the presence or absence of the above bacterial species cannot of itself serve as a reliable predictor of future episodes of recurrent disease in a population of treated patients on a regular trimonthly recall schedule.

Actinobacillus↗
PubMed1991

Subgingival microflora of advanced periodontitis in the Dominican Republic.

A study of the predominant subgingival microflora was carried out in 24 periodontitis patients, 18 to 60 years of age, in Santo Domingo, Dominican Republic. Paper point sampling, transport in VMGA III, and conventional microbiological techniques were utilized. Direct microscopic examination revealed that cocci and nonmotile organisms made up 85% of the total organisms and spirochetes as little as 3%. Nonselective culturing showed Gram-negative organisms to constitute 53% of total isolates. Fusobacterium nucleatum averaged 15%, black-pigmented anaerobes 7%, and Peptostreptococcus micros 10% of the cultivable microflora. Enteric rods and acinetobacter species were recovered from 16 patients and comprised 23% of the cultivable flora. Enterobacter cloacae occurred in 8 patients, Klebsiella oxytoca in 3 patients, and 7 other species in 10 patients. Parallel studies have found a significantly lower prevalence of enteric rods in advanced periodontitis patients in the USA. In conclusion, fewer spirochetes and markedly more enteric rods seem to inhabit adult periodontitis lesions in Santo Domingo patients compared to those in USA. High levels of subgingival enteric rods in periodontitis patients in Santo Domingo may have important prophylactic and therapeutic implications.

Adolescent↗
PubMed1991

Microbial aspects of failing osseointegrated dental implants in humans.

The subgingival microflora of 18 failing implants were examined for pathogenic periodontal microorganisms. Peptostreptococcus micros was recovered from 6 failing implants, Wolinella recta from 6, Fusobacterium species from 5, Candida albicans from 5, and Bacteroides intermedius from 4. Enteric rods or pseudomonads constituted a significant part of the microflora in 5 failing implants. Actinobacillus actinomycetemcomitans, nonpigmented Bacteroides species, Capnocytophage species, and staphylococci were detected in a few implant failures. The present study showed that a complex microflora comprising oral as well as primarily non oral organisms, and bacteria as well as yeasts, can be associated with failing implants. This great diversity in microbial composition and antimicrobial susceptibility among "peri-implantitis" isolates suggest that antimicrobial therapies for implant failures should not be implemented without a prior comprehensive microbiological analysis.

Actinobacillus↗