Bacterial susceptibility to amoxicillin and potassium clavulanate in advanced periodontitis patients not responding to mechanical therapy.

BACKGROUND, AIMS: Between 4 and 8% of periodontitis patients are reported to respond poorly to conventional therapy. In these cases, adjunctive use of systemic antibiotics might be a reasonable therapeutic approach. The purpose of this study was to evaluate the effects of systemic amoxicillin/clavulanate as adjunct to periodontal surgery on the predominant subgingival microorganisms in patients not responding to mechanical therapy. Furthermore, the bacterial susceptibility to amoxicillin/clavulanate was analyzed before and after therapy in order to assess the clinical validity of pre-therapeutic susceptibility testing. METHODS: In 10 periodontitis subjects with no subgingival detection of Actinobacillus actinomycetemcomitans, the predominant subgingival organisms were identified using the identification system Rapid ID 32 A as well as antibiotic susceptibility was tested utilizing the E test. RESULTS: Porphyromonas gingivalis and Prevotella oralis were detected in 7/10 subjects and could no more recovered after therapy. Fusobacterium nucleatum and Peptostreptococcus micros were present in 5/10 patients before treatment, but could be detected in 6/10, resp. 3/10 after therapy. In 4/10 subjects harboring F. nucleatum and in 3/10 with P. micros, those organisms were not targeted by amoxicillin/clavulanate, although post-treatment testing revealed their alleged susceptibility (MICs varied from 0.023 to 0.032 microg/ml, resp. from 0.125 to 2.0 microg/ ml). CONCLUSIONS: The results of this study suggest that the outcomes of conventional methods of susceptibility testing have to be interpreted very carefully when being used for treatment of plaque-related diseases. Furthermore, since the endpoint of systemic antibiotic treatment as adjunct to conventional therapy is elimination of F. nucleatum or P. micros in patients harboring these organisms, the use of amoxicillin/clavulanate appears not to be justified.

Actinobacillus actinomycetemcomitans in destructive periodontal disease. Three-year follow-up results.

BACKGROUND: Convincing data exist that A. actinomycetemcomitans is an etiologic agent of periodontal disease. The purpose of this longitudinal study was to evaluate A. actinomycetemcomitans as a diagnostic indicator for periodontal disease in treated and periodontally maintained patients. METHODS: Following comprehensive mechanical/surgical and supportive amoxicillin plus metronidazole therapy in 13 subjects with A. actinomycetemcomitans-associated destructive periodontal disease, we monitored subgingival A. actinomycetemcomitans at 4 individual sites in each patient up to 3 years post-therapy. The periodontal status was determined, and A. actinomycetemcomitans levels were quantitatively enumerated on TSBV agar in CFU/ml. Six patients with a persistence of subgingival A. actinomycetemcomitans at each reexamination within 3 years post-therapy were selected to be at risk for minor periodontal treatment outcomes and further recurrence of periodontal disease (test group). Seven subjects with a complete suppression of A. actinomycetemcomitans at each post-therapy visit served as controls. RESULTS: The periodontal parameters decreased from overall values of 6.39 mm (probing depth, PD) and 7.64 mm (clinical attachment level, CAL) at the outset to 3.81 mm (PD) and 5.62 mm (CAL) 2 years post-therapy (Friedman, P< or =0.05). At the 3-year reexamination, the PD/CAL scores increased to 4.03/5.78 mm. Among the 6 individuals (46%) with persistence of subgingival A. actinomycetemcomitans at the final 3-year visit (test group), periodontal status yielded increased levels of 4.45 mm (PD) and 6.60 mm (CAL). The control subjects (n = 7) revealed lower values of 3.67 mm (PD) and 5.09 mm (CAL). However, on a patient level, during the 3-year observational trial, the periodontal status of the 13 individuals was not statistically affected by subgingival infection with A. actinomycetemcomitans. CONCLUSIONS: Although in advanced periodontal disease, comprehensive mechanical and antimicrobial treatment is an appropriate regimen for sustained improvement of periodontal health, long-term control of subgingival infection with A. actinomycetemcomitans could not be achieved. In the maintenance care of destructive periodontitis, the persistence of A. actinomycetemcomitans is not a diagnostic parameter for periodontal disease.

Intraoral persistence of Actinobacillus actinomycetemcomitans in periodontally healthy subjects following treatment of diseased family members.

A. actinomycetemcomitans (Aa) can be transmitted among family members. The purpose of the present study was, to evaluate, whether A. actinomycetemcomitans is able to persist for a prolonged period of time in periodontally healthy subjects following elimination of this pathogen from diseased family members. In 14 periodontitis patients harboring Aa as well as in their 37 family members, the clinical (PPD, PAL, P1I, GI) and microbiological status (TSBV) was evaluated. After study patients received mechanical, surgical and antibiotic (3x375 mg amoxicillin+3x250 mg metronidazole/7 d) treatment, they, as well as their family members, were reassessed 3, 6, 9 and 12 months following therapy. From 13 spouses, 4 (31%) had periodontitis associated with Aa, 4 (31%) had periodontitis and no Aa, 2 (15%) were periodontally healthy and harbored Aa, 3 (23%) were healthy with no detection of Aa. From 24 off-springs, one (4%) had periodontitis associated with Aa, 8 (33%) were healthy and harbored Aa, 15 (63%) were healthy with no detection of Aa. In the 2 spouses and in 7 of the 8 offsprings being healthy, but harboring Aa, this pathogen still persisted at the 12-month appointment, after it had been eliminated from the diseased family members. Only one child became negative for Aa after 12 months. The results of this study indicate that A. actinomycetemcomitans is able to persist in the oral habitats of periodontally-healthy subjects for at least 12 months, after this pathogen had been eliminated from diseased family members. This might suggest that also in healthy family members, A. actinomycetemcomitans as a source of transmission should be eliminated to prevent reinfection.

Antibiotic susceptibility of putative periodontal pathogens in advanced periodontitis patients.

In the present study, the antibiotic susceptibility of most prevalent micro-organisms in advanced periodontitis patients was evaluated. In 56 patients, pooled subgingival plaque samples were taken from the deepest site of each quadrant and were cultivated anaerobically. From each patient, the 4 most frequently encountered types of bacterial colonies were subcultured and identified (Rapid ID 32 A). From all bacterial species identified in the 224 subcultures, the 4 most prevalent were used for susceptibility testing to tetracycline, metronidazole and amoxicillin/clavulanate using the E Test. The most prevalent microorganisms were Fusobacterium nucleatum (38/214), Peptostreptococcus micros (33/214), Prevotella oralis (33/214) and Porphyromonas gingivalis (32/214). Regarding antibiotic susceptibility it could be shown that minimal inhibitory concentration (MIC) in all cases was below antibiotic concentrations achievable in gingival crevicular fluid. However, antibiotic resistance was seen in 3 to 29% of the investigated microorganisms.

Microbiological and immunohistological findings in a patient with Papillon-Lefèvre syndrome.

The following communication is a case history of an 11 year-old female patient suffering from Papillon-Lefèvre syndrome. Since a massive occurrence of A. actinomycetemcomitans had been found in the subgingival microflora of the periodontal pockets, the patient was treated with repeated subgingival scaling, with an adjunct Amoxicillin and Metronidazol treatment. A bacteriological examination of the girl's family proved that several brothers and sisters as well as one parent also carried. A. actinomycetemcomitans, showing 3 different strains of this bacterium within the family. An immunohistological examination of the gingival tissue showed a massive inflammatory infiltrate which was dominated by plasma cells. The histological investigation of the first molars did not show morphological abnormalities of the root cementum. Posttreatment clinical and radiographical improvement of the periodontal conditions is reported despite the recurrent finding of A. actinomycetemcomitans.

Simultaneous isolation of Actinobacillus actinomycetemcomitans from subgingival and extracrevicular locations of the mouth.

In the present study, a total of 619 subgingival and extracrevicular samples from 66 early-onset periodontitis, 42 adult periodontitis/gingivitis and 36 treated Actinobacillus actinomycetemcomitans-associated periodontitis patients were selectively cultivated for presence of A. actinomycetemcomitans. The organism was recovered from 68% cases with early-onset periodontitis, 24% cases with adult periodontitis/gingivitis and 50% of treated patients. Associations between recovery from pooled subgingival plaque and samples from extracrevicular locations as well as between different extracrevicular samples, were not heterogeneous with regard to different groups with the exception for cheek/saliva comparisons (odds ratios: early-onset periodontitis 825; adult periodontitis 8.1; treated patients 117; 0.05 < p < 0.1). For associations between recovery of A. actinomycetemcomitans from pooled subgingival plaque/extracrevicular samples, Mantel-Haenszel's odds ratios of between 12.2 and 21.6 were calculated (p < 0.0001). The organism was isolated from 17 cheek mucosa samples of 18 patients identified as still harboring the organism after therapy. Present results point to the considerable value of cheek mucosa samples especially in treated patients to diagnose persistent A. actinomycetemcomitans colonization of the oral cavity.

Actinobacillus actinomycetemcomitans recovery from extracrevicular locations of the mouth.

Associations between recovery of Actinobacillus actinomycetemcomitans from samples of subgingival plaque, and samples of buccal mucosa, tongue and unstimulated saliva were studied in 107 subjects. Ten subjects had gingivitis, 18 localized juvenile periodontitis, 45 rapidly progressive periodontitis and 32 adult periodontitis. Two children suffered from prepubertal periodontitis. Heterogeneity tests for associations in different study populations yielded nonsignificant results. Mantel-Haenszel's common odds ratios were 52.9, 37.2 and 19.8 for respective associations between pooled subgingival samples, and cheek, saliva and tongue samples. Significant McNemar's chi-square of 5.88, 11.25 and 16.96 for respective associations pointed to secondary occurrence of A. actinomycetemcomitans in extracrevicular samples. Multiple linear regression yielded a significant influence of the number of deep periodontal pockets of 7 mm or more and a negative influence of the diagnosis "adult periodontitis" on the log-transformed number of colony-forming units of A. actinomycetemcomitans in samples from cheek mucosa in patients infected with the organism. Extracrevicular occurrence of A. actinomycetemcomitans seems to reflect total subgingival numbers of the organism. Especially sampling cheek mucosa appears to be a promising tool in the diagnosis of a periodontal infection with A. actinomycetemcomitans.

Failure of adjunctive minocycline-HCl to eliminate oral Actinobacillus actinomycetemcomitans.

Considerable problems have been reported in the eradication of Actinobacillus actinomycetemcomitans from periodontal sites. The present communication describes the 2-year results of a comprehensive combined mechanical/surgical and adjunctive minocycline (200 mg/day for 3 and another 2 weeks) treatment regimen in 28 patients with A. actinomycetemcomitans-associated periodontitis. Elimination of A. actinomycetemcomitans at periodontal sites was a prerequisite for gain of clinical attachment of > or = 2 mm or decrease of probing depth to < or = 4 mm after subgingival scaling plus minocycline (p < 0.01). Whereas 2 years after active treatment A. actinomycetemcomitans could not be detected at monitored sites in 23 patients, the organism was found on buccal mucosa and in saliva in 17 and 12 cases, respectively. One or 2 years after periodontal surgery, there was a significant association between log10-numbers of A. actinomycetemcomitans in buccal samples and numbers of residual pockets of > or = 7 mm as well as gingival sites with overt gingivitis (R2 = 0.687, p < 0.001). Present results indicate failure of an even prolonged administration of adjunctive minocycline to eliminate oral A. actinomycetemcomitans in most cases of A. actinomycetemcomitans-associated periodontitis.

A 2-year study of adjunctive minocycline-HCl in Actinobacillus actinomycetemcomitans-associated periodontitis.

To study the effects of a step-wise treatment regimen on Actinobacillus actinomycetemcomitans-(Aa) associated periodontitis, 4 clusters among 33 patients harboring the organism were followed during successive periods of systemic minocycline plus mechanical debridement and minocycline plus modified Widman flap treatment. Localized periodontitis was found in 2 clusters, one with 7 localized juvenile periodontitis patients and a 24-year old male with localized destruction and extremely low plaque levels (LJP), and the other consisting of 10 patients with plaque and gingivitis and a wider age range (16 to 54 years, LP). Generalized severe and moderate periodontitis was found in 2 clusters which were further discriminated by severe gingivitis and high levels of supragingival plaque (9 patients, GSP), and mild inflammation and low plaque levels (6 patients, GMP). Mean percentages of Aa, as determined by selective cultivation of microbiota from at least 2 periodontal pockets of 6 mm or more were 63, 16, 33, and 7.8% in the clusters (P < 0.01). Six months after active treatment, Aa was present in 6/9 patients and 50% of sites in GSP, and 3/6 patients and 46% of sites in GMP patients. In contrast, the organism was virtually eliminated by scaling and flap procedures in the localized periodontitis clusters, and did not reappear after 6 months (P < 0.05). Combined antibiotic, mechanical, and surgical therapy resulted in a persistence of 20% of sites with residual probing depth of > or = 4 mm in GMP patients after active therapy. At this point, 3 of the GMP patients and 1 GSP patient left the study. Multiple regression analysis showed a significant influence of log-transformed numbers in Aa in cheek and saliva samples at the end of the study, and cluster on the percent residual number of sites with periodontal probing depth of > or = 7 mm (P < 0.001). The present results suggest that the applied therapy would be appropriate in localized forms of Aa periodontitis, but inappropriate in more severe and generalized forms to predictably eliminate Aa. Controlled long-term studies with larger groups of patients will be needed to establish the difference in treatment response suggested by these studies.

[Actinobacillus actinomycetemcomitans on oral mucosa]. / Actinobacillus actinomycetemcomitans auf oralen Schleimhäuten.

The present study was carried out to delineate the parameters influencing the extracerevicular oral colonization of Actinobacillus actinomycetemcomitans. Numbers of cultivable A. actinomycetemcomitans in subgingival plaque samples, saliva, and samples from buccal and tongue mucosae were determined in 33 patients with A. actinomycetemcomitans-associated periodontitis. Subgingival samples from patients with localized juvenile periodontitis (LJP) had significantly higher levels of A. actinomycetemcomitans than samples obtained in non-LJP patients (740,000 vs. 59,000, median, p less than 0.05). Samples from buccal mucosae and saliva were infected with A. actinomycetemcomitans in 85 vs. 70%, and 77 vs. 65%, respectively. Multiple regression analysis of log 10-transformed counts of A. actinomycetemcomitans in samples from cheek as dependent variable yielded a significant influence of numbers of deep periodontal pockets and diagnosis. The occurrence of A. actionomycetemcomitans on buccal mucosa seems to reflect the overall subgingival load with the organism.

Morphological compositions of subgingival microbiota in Actinobacillus actinomycetemcomitans-associated periodontitis.

Infrequent occurrence of spirochetes and rather low proportions of these organisms have been reported in localized juvenile periodontitis, where periodontal lesions often harbour large numbers of Actinobacillus actinomycetemcomitans, a suspected principal periopathogen strongly implicated in the pathogenesis of this and other forms of chronic periodontitis. We studied the association of subgingival A. actinomycetemcomitans with the morphological composition of the subgingival microbiota in a large population of patients suffering from advanced periodontitis. Subgingival plaque from the deepest pockets of every quadrant of their dentitions was sampled and pooled in 70 patients between 14 and 63 years of age, and analysed morphologically by phase-contrast microscopy. A minimum % similarity index was employed to define 4 clusters with different morphological composition of the floras. The actual proportion of A. actinomycetemcomitans was determined at 2 sites with deep periodontal pockets. All clusters harboured patients infected with A. actinomycetemcomitans. If present, in clusters predominated by motile rods or medium-sized spirochetes, the organism was found in rather low proportions (median 5.3% and 3.4%, respectively). However, the cluster with a pooled flora mainly consisting of coccoid cells revealed periodontal sites with A. actinomycetemcomitans in proportions of more than 53% (median), if the organism was present (p less than 0.01). We found a positive correlation between proportions of A. actinomycetemcomitans and cocci (R = 0.65) and negative correlations with spirochetes and motile rods (R = 0.61, R = -0.59, respectively). Cautious interpretation of subgingival plaque predominated by coccoid cells is recommended, if deep periodontal pockets and obvious signs of inflammation are present, since these pockets were found to be often infected with large numbers of A. actinomycetemcomitans.

[Concentrations of A. actinomycetemcomitans in subgingival plaque following short-term minocycline therapy]. / Konzentrierung von A. actinomycetemcomitans in subgingivaler Plaque nach kurzfirstiger Minocyclin-Therapie.

In the present study we examined alterations in the proportions of cultivable flora of A. actinomycetemcomitans (A.a.) in subgingival plaque of 25 patients with different forms of periodontitis, 7 days after systemic administration of 200 mg/d Minocycline-HCl. Remarkable shifts in the flora were apparent. Sites with low or extremely low initial levels of A.a. (less than 10%) showed an increase in mean proportions from 2.7% to 15.7% (p less than 0.01). A.a. was eliminated in only 18% of sites after 1 week of minocycline therapy. Subgingival scaling resulted in 80% of sites without detectable A.a. However, if present, the organism accounted for 51% of the cultivable microflora, on average. Our data emphasize the importance of a sufficiently extended period of antibiotic therapy and efficient mechanical debridement of all tooth surfaces to eliminate the organism.

[Quantifying bacteriological findings in the subgingival flora]. / Zur Quantifizierbarkeit einiger bakteriologischer Befunde in der subgingivalen Flora.

The variation of selected bacteriological parameters was investigated in 25 untreated A. actinomycetemcomitans-associated periodontitis patients. Samples of subgingival plaque were collected twice within 6 weeks with paper points for cultivation as well as with curettes for analyses of the morphological composition. Total counts of colony forming units, counts of A. actinomycetemcomitans as well as proportions of spirochetes were determined. Our results suggest a high reproducibility of quantitative data if a standardised sampling procedure with paper points is employed. On the other hand, considerable differences were observed in the morphological composition of subgingival plaque.

Multiple periodontal abscesses after systemic antibiotic therapy.

Multiple periodontal abscesses were reported in medically compromised patients. We examined patients with a non-contributory medical history referred for the treatment of numerous periodontal abscesses. All patients had taken oral broad spectrum antibiotics 1 to 3 weeks prior to the outburst of the abscesses (8 patients: penicillin, 2 patients: tetracycline). The patients suffered from advanced periodontal disease, 82% of the examined sites showed probing depths greater than 3 mm, 56% attachment loss greater than 3 mm. Subgingival plaque samples were analysed from 2 different abscess sites. Bacteroides gingivalis (19/20), Fusobacterium nucleatum (13/20) and Streptococcus intermedius (13/20) were the most prevalent anaerobic microbiota. Strains resistant to the prescribed antibiotic were found in 55% (11/20) of the subgingival plaque samples. It was concluded that in patients with advanced periodontal disease, systemic antibiotic therapy without subgingival debridement may change the composition of the subgingival microbiota, thus favouring the outburst of multiple periodontal abscesses.

Actinobacillus actinomycetemcomitans contamination of toothbrushes from patients harbouring the organism.

The main ecological niche of Actinobacillus actinomycetemcomitans (A.a.) seems to be the periodontal pocket, but it can also be isolated from supragingival plaque, buccal and tongue mucosa, or saliva. We examined toothbrushes from 21 patients, all identified as harbouring moderate to large numbers of A.a. in subgingival plaque, for contamination with this organism. 29% of the toothbrushes presented by our patients yielded detectable numbers of A.a. Immediately after toothbrushing this figure rose to 62%, but dropped to 50% after 1 h. Numbers of isolated A.a. on toothbrushes were weakly correlated with the degree of periodontal destruction, and significantly more numbers of A.a. on toothbrushes could be detected if the organism was found on mucous membranes or in saliva. There was no association with gingival inflammation, supragingival plaque nor mean numbers of isolated subgingival A.a.

[Vital staining and phase contrast microscopy results of plaque smears]. / Vitalfärbung und phasenkontrastmikroskopische Auswertung von Plaqueausstrichen.

The information about the vitality of the plaque is limited. Only motile bacteria can be distinguished as alive. Vital staining allows to differentiate between living nonmotile rods and dead, previously motile rods. With increasing severity of the periodontal destruction, the proportion of alive respectively motile rods and vibrions increases. The vital staining shows very clearly the relation between destruction and living rods.

[Efficacy of a PVP-iodine compound on selected pathogens of the oral cavity in vitro]. / Wirksamkeit eines PVP-Jod-Präparates in vitro auf ausgewahlte Mundhöhlenkeime.

The study was designed to test the efficacy of a PVP-iodine antiseptic agent on potentially pathogenic oral bacteria. A 0.5% concentration of the test compound was sufficient to inhibit the growth of 7 out of 8 tested strains. Only bacteroides gingivalis continued to grow during exposure to a 0.5 and 1% concentration of the test compound. Quantitative suspension experiments demonstrated that the onset of action occurred within five minutes. Quantitative suspension experiments with protein loading resulted in a lower efficacy of the tested agent. Results indicate that the tested compound may be recommended as an oral disinfectant.

[Reduction of A. actinomycetemcomitans in the subgingival microflora of adult advanced periodontitis]. / Die Reduktion von A. actinomycetemcomitans bei der profunden Parodontitis.

In 15 adult patients with severely advanced periodontal disease unrelated to localized juvenile periodontitis high numbers of A. actinomycetemcomitans (A. a.) were identified in samples of subgingival plaque (median log CFU 5.13). In order to correlate clinical conditions with bacteriological findings, in every patient 2 deep periodontal pockets were treated with a 3-phase regimen of minocycline administration, mechanical, and surgical periodontal therapy. A. a. was eliminated by minocycline alone in 2 cases. Minocycline in combination with subgingival scaling resulted in 6 patients in A. a. negative samples. Following termination of minocycline therapy, frequently increasing numbers of A. a. were observed. Patients showed significant gain in clinical attachment or reduction of probing pocket depth during different phases of therapy, but only if A. a. was suppressed close to or below the lower limit of detection (5 CFU/ml). Considerable problems with elimination of A.a. may be connected with frequently observed recurrent periodontal disease in these patients.

[Electron microscopic visualization of microbial extracellular metabolic products in an in vitro test]. / Zur elektronenmikroskopischen Darstellung mikrobieller extrazellulärer Stoffwechselprodukte im in-vitro-Test.

The present electron microscopic study was performed to investigate the glycocalyx changes of S. mutans species OMZ 176 during incubation with defined substrate limitation (sucrose) and with hydroxyapatite crystals. In an agar with 5 p. c. sucrose can be seen the build-up of proteoglycan complexes, and a strong cell free glycan production in order to hydroxyapatite crystals.