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J Slots

Publications and source records attributed to J Slots.

At least 91 records · Page 5Linked to original sources

Likelihood of transmitting Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in families with periodontitis.

This study examined the frequency of spouse-to-spouse and parent-child transmission of the periodontal pathogens Actinobacillus actinomycetemcomitans (124 subjects in 47 families) and Porphyromonas gingivalis (78 subjects in 31 families). The two test organisms were recovered from subgingival and tongue surface specimens using established microbiological techniques. Arbitrarily primed polymerase chain reaction (AP-PCR) was used to genetically characterize isolates of the test species. The probability of isolating identical AP-PCR types of A. actinomycetemcomitans and P. gingivalis in family members by chance was estimated from the AP-PCR genotype distribution of the two species among unrelated individuals. A probability of 5% or less for occurrence by chance alone suggests intra-familial transmission. With a bacterium-positive spouse, A. actinomycetemcomitans revealed inter-spousal transmission in 4/11 (36%) married couples and P. gingivalis in 2/10 (20%) married couples. Parent-child transmission of A. actinomycetemcomitans took place in 6/19 (32%) families. P. gingivalis was not transmitted from parent to child in any of the study families. The intra-familial transmission of A. actinomycetemcomitans and P. gingivalis may in part explain a familial pattern of periodontitis and may have important prophylactic and treatment implications.

Adolescent↗

Utility of 5 major putative periodontal pathogens and selected clinical parameters to predict periodontal breakdown in patients on maintenance care.

The predictive utility of 5 major putative periodontopathic microbial species, "superinfecting" organisms, and several clinical periodontal parameters were assessed relative to periodontitis recurrence over a 12-month period in 78 treated adult patients participating in a 3-month maintenance care program. At baseline, pooled subgingival microbial samples were collected from each patient, and whole-mouth evaluations of probing depth, relative periodontal attachment level, furcation involvement, and indices of plaque and gingival inflammation were carried out. 67 (85.9%) subjects were culture-positive at baseline for presence of either Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Campylobacter rectus or Peptostreptococcus micros, with 48 (61.5%) subjects yielding one or more of these species at or above designated threshold proportions of > or = 0.01% for A. actinomycetemcomitans, > or = 0.1% for P. gingivalis, > or = 2.5% for P. intermedia, > or = 2.0% for C. rectus, and > or = 3.0% for P. micros. Subgingival yeasts were recovered from 12 subjects, staphylococci from 7, and enteric rods/pseudomonads from 6; however, no subjects revealed > or = 1.0% baseline proportions of these "superinfecting" organisms in subgingival specimens. Periodontitis recurrence in subjects was defined as any periodontal site exhibiting either a probing depth increase of > or = 3 mm from baseline, or a probing depth increase of > or = 2 mm from baseline together with a loss in relative periodontal attachment of > or = 2 mm from baseline. 15 (19.2%) study subjects showed periodontitis recurrence within 6 months of baseline, and 25 (32.1%) within 12 months. The mere baseline presence of the 5 major test species and "superinfecting" organisms were not significant predictors of periodontitis recurrence over 12 months. However, a 2.5 relative risk for periodontitis recurrence over 12 months was found for subjects yielding one or more of the 5 major test species at or above the designated baseline threshold proportions (p = 0.022, Mantel-Haenszel chi 2 test). The positive predictive value for periodontitis recurrence of a microbiologic analysis encompassing the 5 major test species at or above the designated threshold proportions improved with increasing time from baseline, up to approximately 42% at 12 months. Baseline variables jointly providing in multiple regression analysis the best predictive capability for periodontitis recurrence in subjects over a 12-month period were recovery of one or more of the 5 major test species at or above designated threshold proportions, the proportion of sites per subject with > or = 5 mm probing depth, and the mean whole-mouth probing depth. These findings indicate that one or more of 5 major putative periodontal pathogens in elevated subgingival proportions together with increased probing depth predispose adults on maintenance care to recurrent periodontitis.

Adult↗

Efficacy of CPITN sextant scores for detection of periodontitis disease activity.

The relationship between CPITN sextant scores and periodontitis recurrence at individual tooth sites was evaluated in a longitudinal study in 83 treated adult periodontitis patients receiving systematic 3-month maintenance care. At baseline and semi-annual examinations over 36 months, CPITN scores were assigned to each dentition sextant using probing depths and gingival index scores, and relative periodontal attachment level was assessed at individual tooth sites using an occlusal reference stent. Periodontitis recurrence was defined as any periodontal site exhibiting either a probing depth increase of > or = 3 mm from baseline, or a probing depth increase of > or = 1 mm from baseline together with a loss of relative periodontal attachment of > or = 2 mm from baseline. 49 (59.0%) subjects developed periodontitis recurrence in 147 (29.8%) sextants at 181 (2.2%) individual periodontal sites during the 36-month study period. Baseline CPITN scores of 4 were more common in disease-active subjects than clinically-stable subjects (p = 0.003, t-test), and were associated with a statistically significant 1.66 relative risk of periodontitis recurrence within 36 months. CPITN sextant scores of 3 or 4 showed low specificity and low positive predictive values as indicators of periodontitis recurrence at > or = 1 individual sites within the affected sextant. In comparison, low CPITN sextant scores (0-2) provided high specificity (96.2-100%), high positive predictive values (99.5-100%), and a summary odds ratio of 24.2 as an indicator of clinical stability at all periodontal sites within a given dentition sextant. Changes in sextant scores for CPITN over 6-month periods showed no relationship with periodontitis recurrence at individual periodontal sites. This study suggests that while CPITN is inadequate for detection of periodontitis recurrence, low CPITN scores provide rapid presumptive identification of clinically-stable sextants in adult periodontitis patients on maintenance care.

Adult↗

The dynamics of microbial colonization of barrier membranes for guided tissue regeneration.

The microbial colonization of expanded polytetrafluoroethylene membrane by putative periodontopathogens at 3 minutes of intraoral manipulation was determined in 42 patients with 42 mandibular posterior two- to three-wall defects. Twenty patients exhibited no periodontal pockets of > or = 5 mm, other than the study site, and low levels of pathogens (group A). Twenty-two patients revealed multiple periodontal pockets of 5 mm or more and numerous pathogens (group B). Within the preceding 3 months of regenerative surgery, group A patients had received apically positioned flap surgery with osseous recontouring (except for the study site), and group B patients had been enrolled in a non-surgical maintenance program. The subgingival microbiota was examined prior to regenerative therapy, and the membrane microbiota was examined at 3 minutes and at the time of removal at 6 weeks by culture, DNA probes, and phase-contrast microscopy. The mean initial defect depth was 7.4 mm for group A and 7.2 mm for group B. At 6 months, the difference in mean clinical attachment gain was statistically significant (P < 0.001; group A: 3.4 mm; group B: 1.4 mm). At 3 minutes, putative pathogens were detected in seven (16.7%) membranes in group B (group Binfected), and the associated sites gained only 0.6 mm in clinical attachment at 6 months. Clinical attachment gain was modeled as a linear function of the explanatory variables (r2 = 86%). The presence of Porphyromonas gingivalis detected by DNA probe at 3 minutes was associated with 1.5 mm less expected gain (P = 0.0002). Total microbial counts and the percentage of Peptostreptococcus micros and Capnocytophaga species at baseline, and of motile rods on the membrane surface facing the gingiva at 6 weeks, were statistically significant negative predictors of clinical attachment. For each week the membrane remained covered, an additional 0.5 mm gain could be expected (P = 0.002); and for every 10 sites that exhibited bleeding on probing, the clinical attachment gain was 0.6 mm less at the site of regeneration (P < 0.0001). The present results showed that putative pathogens may colonize membranes within 3 minutes of intraoral manipulation. The patient group treated with periodontal osseous surgery revealed the lowest levels of periodontal pathogens in the membranes and exhibited the most gain in clinical attachment.

Adult↗

Immune response to anaerobic bacteria in patients with peritonsillar cellulitis and abscess.

The role of four oral organisms (Fusobacterium nucleatum. Prevotella intermedia, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans) was investigated in 19 children with peritonsillar abscess, and 17 with peritonsillar cellulitis. Antibody titers to these organisms were measured by enzyme- linked immunosorbent assay in the patient, as well as in 32 control patients. Serum levels in the patients were determined at day 1 and 42-56 days later. Significantly higher antibody levels to F. nucleatum and P. intermedia were found in the second serum sample of patients with peritonsillar cellulitis or abscess, as compared to their first sample or the levels of antibodies in controls. A total of 136 bacterial isolates, 100 anaerobic and 36 aerobic were isolated from the 19 peritonsillar abscesses. Anaerobic bacteria were found in all abscesses, and they were mixed with aerobic bacteria in 5 (26%). F. nucleatum was recovered in 14 (74%) abscesses and P. intermedia was isolated in 13 (68%). The elevated antibody levels to F. nucleatum and P. intermedia, known oral pathogens, suggest a pathogenic role for these organisms in peritonsillar infections.

Abscess↗

Comparison of arbitrarily primed polymerase chain reaction and ribotyping for subtyping Actinobacillus actinomycetemcomitans.

This study investigated the compatibility of arbitrarily primed polymerase chain reaction (AP-PCR) and ribotyping in the characterization of Actinobacillus actinomycetemcomitans , a major pathogen in the mixed anaerobic microflora of human periodontitis. AP-PCR was performed directly on lysed bacterial colonies using a random-sequence 10-base oligonucleotide primer. Ribotyping was carried out by using purified bacterial chromosomal DNA digested with BglI. DNA fragments were separated electrophoretically, blotted onto a nylon membrane and hybridized with the plasmid pKK3535 containing the rRNA operon of Escherichia coli. The two genetic methods were evaluated on isolates from single individuals and from family members. Twelve AP-PCR types and 47 ribotypes were distinguished among 76 A. actinomycetemcomitans isolates of different serotypes. AP-PCR typing and ribotyping gave compatible results in 18 of 20 comparisons. Although AP-PCR detected less genetic heterogeneity in A. actinomycetemcomitans than ribotyping, the rapid and relatively simple AP-PCR technique seems to be sufficiently discriminative to be used in large scale epidemiological studies which preclude the application of the more laborious ribotyping technique.

Journal Article↗

Detection of putative periodontal pathogens in subgingival specimens by 16S ribosomal DNA amplification with the polymerase chain reaction.

The utility of the 16S ribosomal RNA-based polymerase chain reaction (PCR) for detection of Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Campylobacter rectus, Eikenella corrodens, Porphyromonas gingivalis, Prevotella intermedia, and Treponema denticola was examined and compared with that of anaerobic culture. Primer pairs consisting of 20-27 nucleotides amplified 404- to 688-bp regions of 16S ribosomal RNA genes of these organisms. This method had a lower detection limit of 50 target cells in a background of 10(7) cells. Its specificity for B. forsythus, P. gingivalis, and T. denticola seemed high. The primers for A. actinomycetemcomitans, C. rectus, and P. intermedia cross-reacted with some closely related species but did not reveal amplification products in tests with more distantly related organisms. The primers for E. corrodens did not seem to cross-react with oral organisms. This PCR technique was sensitive, reproducible, and easy to perform. PCR-based amplification may prove valuable for the detection of some periodontal pathogens in crude subgingival specimens.

Adult↗

Actinobacillus actinomycetemcomitans genotypes in relation to serotypes and periodontal status.

Actinobacillus actinomycetemcomitans is prevalent in periodontitis but is found in some periodontally healthy individuals as well. The arbitrarily primed polymerase chain reaction (AP-PCR) was used to fingerprint clinical A. actinomycetemcomitans isolates of different serotypes to determine the association between individual clonal types and periodontal conditions. Fifteen different AP-PCR genotypes were distinguished among 93 A. actinomycetemcomitans isolates from 86 uncohabiting individuals with adult periodontitis, localized juvenile periodontitis or no periodontal destruction. The 3 most common AP-PCR genotypes accounted for 68% of the isolates. Seven of the remaining AP-PCR genotypes were found only in periodontitis. The isolates of a given AP-PCR genotype usually belonged to the same serotype. The distribution of the AP-PCR genotypes among serotype b isolates seemed to differ among the subject groups. The results revealed a major genetic dissimilarity between A. actinomycetemcomitans serotypes and suggested a relationship between some A. actinomycetemcomitans clones and periodontal disease.

Aggregatibacter actinomycetemcomitans↗

Molecular genetic detection of Bacteroides heparinolyticus in adult periodontitis.

Bacteroides heparinolyticus in subgingival plaque was identified using a digoxigenin-labeled whole genomic DNA probe and a polymerase chain reaction (PCR) assay based on 16S rRNA species-specific primers (5'-ATG GTG ATT CCG CAT GGT TTC TCC-3' (base position, 188-212) and 5'-CAA ACT TTC ACA GCT GAC TTA AGC-3' (592-615)). Subgingival specimens obtained by paper points from 3 deep periodontal pockets in each of 113 adults were examined. The DNA probe reacted with all pure isolates tested of B. heparinolyticus and did not react with other oral species tested; the probe showed positive reactions in 74.3% of the patient samples examined. The PCR primers produced the 428 bp species specific amplification product in all B. heparinolyticus test strains and did not reveal detectable amplicons with strains of other subgingival species. The PCR method detected 50 B. heparinolyticus cells dispersed in subgingival plaque. PCR only revealed B. heparinolyticus in 6.2% of the patient samples studied. The higher level of positive specimens with the DNA probe was probably due to false-positive reactions from cross-hybridization with unknown subgingival species. This study suggests that the PCR method amplifying specific 16S rRNA sequences represents an easy and valuable means to detect B. heparinolyticus in subgingival plaque. The low prevalence of subgingival B. heparinolyticus does not incriminate the organism in the etiology of adult periodontitis.

Adult↗

Periodontal pathogens on polytetrafluoroethylene membrane for guided tissue regeneration inhibit healing.

This study determined the microbial composition of the apical parts of the expanded polytetrafluoroethylene membrane surfaces facing the gingiva and the tooth in guided tissue regeneration. Microbial and clinical features of 2-to-3 wall periodontal bony defects treated with membranes with and without concomitant use of systemic Augmentin therapy were also determined. 18 patients with 18 study sites participated. 9 patients received systemic 500 mg Augmentin 1 h prior to surgery, and 500 mg TID for 8 days thereafter. 9 patients received no systemic antimicrobial therapy. Microbiological examination was performed 1 h prior to surgery, at the time of membrane removal at week 6, and at 6 months post-surgery. Microbial morphotypes, total viable counts, and the occurrence of selected microbial species were determined by phase-contrast microscopy, selective and non-selective culture, and DNA probes. Study sites were examined for probing pocket depths and attachment levels. At baseline, no microbial or clinical parameter showed statistical differences between groups. At 6 months, the Augmentin group demonstrated a significantly higher (P = 0.032; Student t-test) mean probing attachment gain (36.5% of potential gain to the cemento-enamel junction) than the 9 control patients (22.4% of potential gain). At the time of removal, membranes in the Augmentin group showed significantly fewer organisms than membranes in the control group (52.2 x 10(6) versus 488.6 x 10(6)). Sites free of pathogens on the membrane surface toward the tooth gained the most clinical attachment, even in the presence of various pathogens on the gingiva-facing membrane surface.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗