Serum antibodies to Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in juvenile periodontitis and adult periodontitis (part I)

Recent microbiological studies support the concept that specific gram negative bacteria play a major role in the etiology and pathogenesis of human chronic inflammatory periodontal disease. Actinobacillus actinomycetemcomitans has been isolated frequently from juvenile periodontitis and Porphyromonas gingivalis has been shown to be a prominent species in adult periodontitis in humans. The purpose of this study was to determine levels of the specific antibodies to A.actinomycetemcomitans and P.gingivalis in 17 patients with juvenile and 15 patients with adult periodontitis and 24 healthy subjects. IgG and IgM antibody titers against these antigens were determined by enzyme-linked immunosorbent assay (ELISA). The levels of antibodies against A.actinomycetemcomitans were significantly higher in the juvenile periodontitis compared to the adult periodontitis patients and controls. Anti-P.gingivalis antibodies were elevated in adult periodontitis compared to juvenile periodontitis patients and controls.     

The effects of periodontal therapy on serum antibody levels to Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis (part II)

Levels of IgG and IgM antibodies were estimated against Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were determined by enzyme linked immunosorbent assay (ELISA) in 17 patients with juvenile periodontitis, 15 with adult periodontitis and 24 healthy controls at the beginning of treatment and 3 to 8 months after periodontal therapy. After treatment, antibodies to A. actinomycetemcomitans and P.gingivalis had decreased in patients, but the levels were still significantly higher than in healthy controls. Whether or not an of antibody level against a specific bacteria changes after periodontal treatment is however, still debatable.     

Epidemiology and transmission of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans among children and their family members. A report of 4 surveys

The distribution and transmission of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans in 4 families were studied. The families were included, based on the isolation of P. gingivalis from a young child or adolescent. The probands of these 4 families were: a 5-year old periodontally healthy boy; a 17-year old girl with severe generalized juvenile periodontitis; an 11-year old girl with prepubertal periodontitis; 2 sisters, 5 and 17-years old, with untreated severe periodontitis as a component of the Papillon-Lefèvre syndrome. All members of the 4 families were examined clinically and microbiologically for the presence of P. gingivalis and A. actinomycetemcomitans. Most of the parents appeared to be adult periodontitis patients; the parents of one proband were edentulous. Results showed that in all cases at least one of the parents was positive for P. gingivalis. On the basis of indistinguishable restriction endonuclease patterns (REPs) of P. gingivalis and A. actinomycetemcomitans isolates from parents and their children, and distinct REPs from unrelated individuals, the present study indicates that P. gingivalis and A. actinomycetemcomitans were transmitted between parents and their children.     

Low back pain in college athletes. A prospective study correlating lower extremity overuse or acquired ligamentous laxity with low back pain

This study compared the presence of 6 periodontopathic bacteria in whole saliva and subgingival plaque of 202 subjects. The test bacteria were identified using a 16S rRNA-based PCR detection method. Each study subject contributed a whole saliva sample and a paper point sample pooled from the deepest periodontal pocket in each quadrant of the dentition. The kappa test revealed a fair agreement between the presence of Porphyromonas gingivalis, Prevotella intermedia, and Treponema denticola in whole saliva and periodontal pocket samples (kappa > 0.4). The McNemar test showed that the differences between sample types were due to a more frequent detection of the 3 organisms in whole saliva than in periodontal pocket samples (P < 0.01). Prevotella nigrescens also was detected more frequently in whole saliva than in periodontal pocket samples (P < 0.01; McNemar test). Although little agreement between samples was found for Actinobacillus actinomycetemcomitans and Bacteroides forsythus (kappa < or = 0.4), neither whole saliva nor pocket samples showed better detection for these 2 species (P < 0.01, McNemar test). The results indicate that whole saliva is superior to pooled periodontal pocket samples to detect P. gingivalis, P. intermedia, P. nigrescens, and T. denticola in the oral cavity. The detection of oral A. actinomycetemcomitans and B. forsythus with reasonably good accuracy may require both whole saliva and periodontal pocket samples.     

The prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Bacteroides forsythus in humans 1 year after 4 randomized treatment modalities

The relationship between probing attachment changes in treated periodontal pockets and the prevalence of selected periodontal pathogens was assessed in 10 patients with adult periodontitis 1 year following randomized therapy. All patients had at least 1 tooth in each quadrant with an inflamed pocket of probing depth > or =5 mm and clinical attachment loss and harbored at least one of the following 3 major periodontal pathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, or Bacteroides forsythus. The number of target organisms per site was determined preoperatively; at 1 week; and at 1, 3, 6, and 12 months postoperatively utilizing DNA probes. The following clinical parameters were measured and recorded preoperatively and at 1, 3, 6, and 12 months post-treatment: gingival fluid flow, gingival index, plaque index, probing depth, probing attachment level, gingival recession, and bleeding on probing. One quadrant in each patient was randomly assigned to 1 of the following 4 treatments: 1) scaling and root planing; 2) pocket reduction through osseous surgery and apically-positioned flap; 3) modified Widman flap; and 4) modified Widman flap and topical application of saturated citric acid at pH 1 for 3 minutes. All 4 treatments were rendered in one appointment using local anesthesia. No postoperative antibiotics were used, but patients rinsed with 0.12% chlorhexidine for the first 3 months postoperatively and received a prophylaxis every 3 months. This investigation revealed: 1) 30.0% of the sites were infected by at least 1 species at 3, 6, and 12 months postoperatively. 2) Failing sites were infected by a high number of both Pg and Bf These sites had a mean of 24.2+/-9.0 x 10(3) Pg and 93.1+/-42.0 X 10(3) Bf while stable sites had a mean of 6.8+/-0.5 x 10(3) Pg and 7.2+/-1.2 x 10(3) Bf (P = 0.06 and P = 0.05, respectively). 3) The infected sites lost significantly more mean clinical attachment at 12 months (1.5+/-0.5 mm compared to a loss of 0.2+/-0.3 mm for uninfected sites, P = 0.017). 4) The infected sites had a significantly greater BOP (67+/-14% versus 25+/-8% for uninfected sites at 12 months, P = 0.012). 5) The choice of treatment modality did not affect the prevalence of the target species at 1 year post-treatment. These results suggest that prevalence of microbial pathogens negatively affects the 1 year outcome of periodontal surgical and nonsurgical therapy.     

Periodontal findings in elderly patients with non-insulin dependent diabetes mellitus

The periodontal status of 25 patients with non-insulin dependent diabetes mellitus (NIDDM) (age range 58 to 76) was investigated and compared with 40 non-diabetic control subjects (age range 59 to 77). Surfaces with visible plaque and bleeding after probing, calculus, recessions, and pathological pockets were examined. The total attachment loss was calculated as a sum of recessions and pockets in millimeters. Mesial and distal bone loss was measured from panoramic radiographs and mean alveolar bone loss was calculated. Periodontal disease was considered advanced when mean alveolar bone loss was over 50%, or 2 or more teeth had pockets > or = 6 mm. Microbiological analysis comprised the detection of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Bacteroides forsythus by a polymerase chain reaction (PCR) method. Patients with NIDDM had significantly more often advanced periodontitis than control subjects, 40.0% and 12.5%, respectively. Diabetic patients did not harbor more pathogens than the control subjects. The HbA1C level deteriorated in patients with advanced periodontitis, but not in other patients with NIDDM, when compared to the situation 2 to 3 years earlier. Advanced periodontitis seems to be associated with the impairment of the metabolic control in patients with NIDDM, and a regular periodontal surveillance is therefore necessary.     

Microflora of periodontal pockets in advanced periodontitis

The aim of study was the evaluation of periodontal pockets microflora in patients with advanced periodontitis. From each subject 16-20 samples were taken using paper points. Pooled sample after 60 s. mixing was serially diluted in reduced BHI. For total cell counts and for the isolation of black pigmented anaerobes Brucella agar supplemented with 5% sheep blood, hemin, menadione, with and without Kanamycin-Vancomycin mixture and BM agar plates were used. For isolation of A. actinomycetemcomitans TSBV agar plates were used. Cultures were incubated in anaerobic chamber at 37 degrees C for 7 days and TSBV agar plates in an atmosphere of 95% air-5% CO2 at 37 degrees C for 5 days. Microorganisms were identified by Gram staining, colony morphology, fluorescence in UV-light, haemagglutination of 3% sheep erythrocytes, fermentation of sugars, production of indole, urease (API 20A), specific enzymes (Rapid ID 32A). Twenty seven subjects with clinically recognized periodontitis were examined. Microorganisms important in periodontitis were isolated from periodontal pockets of almost all examined subjects. The number of bacteria obtained from the sample of one patient ranged from 1 x 10(4) CFU/ml to 3,6 x 10(6) CFU/ml. Porphyromonas gingivalis was identified in the samples taken from 17 patients, Prevotella intermedia-19, Actinobacillus actinomycetemcomitans -11, Fusobacterium nucleatum-9, Peptostreptococcus spp.-22.     

Diagnostic utility of specific microbiological markers for periodontal diseases

Specific detection of marker organisms Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans with an immunoassay provided 2 types of useful information directly into private clinical practice: 1) persistence of P. gingivalis in patients undergoing regular treatment allowed rapid identification of pockets requiring further treatment without waiting for measurable progression of lesions and 2) presence of A. actinomycetemcomitans in adults at any stage of diagnosis or treatment identified patients who may prove to have difficult-to-manage periodontitis. We made these findings in 253 patients (234 in specialist periodontal practices [F-ME 55; MHM 179] and 19 in general dental practice [EWM]). The search for useful diagnostic markers overlaps only partly with the search for periodontal pathogens. The P. gingivalis marker and the A. actinomycetemcomitans marker identify 2 different patterns of infection that appear to reflect 2 different underlying problems. Demonstration of pocket-dependent infection with P. gingivalis in treated patients provides an outcome marker for sites not converting to marker-negative sites at detection levels of the immunoassay. This information facilitates selection of sites and patients requiring adjustment of treatment regimens. Detection of A. actinomycetemcomitans in adult patients is significantly associated with periodontitis characterized as refractory. Positive identification of A. actinomycetemcomitans with the immunoassay supports clinical decision-making by drawing attention to adult patients who require closer monitoring and intensive persistent treatment. Successful application of immunoassay detection of microbiological markers is based on continuous patient monitoring to support clinical decisions; it does not replace careful clinical judgment.     

Reduced serum IgG reactivities with bacteria from dental plaque in HIV-infected persons with periodontitis

Serum samples were obtained from 44 HIV-seropositive (HIV+) and 37 HIV-seronegative (HIV-) persons that were grouped according to periodontal status. Serum IgG and IgA reactivities towards Streptococcus mutans, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis. Prevotella intermedia, Prevotella nigrescens and Fusobacterium nucleatum were measured by means of ELISA. HIV+ persons with chronic marginal periodontitis showed significantly lower IgG reactivities to the periodontal pathogens A. actinomycetemcomitans, P. gingivalis, P. intermedia and F. nucleatum as compared with their HIV- counterparts (p < 0.05). Specific serum IgA reactivities were similar in the two periodontitis groups, except for P. nigrescens where the HIV+ group with chronic marginal periodontitis had lower values than their systemically healthy counterparts (p < 0.05). The results indicate that HIV infection affects the humoral serum immune responses against bacteria in dental plaque; the depressed antibody responses may contribute to the increased susceptibility for periodontal infections in HIV-infected patients.     

Attachment loss and serum antibody levels against autologous and reference strains of Actinobacillus actinomycetemcomitans in untreated localized juvenile periodontitis patients

Immunological data have been suggested to be a potential tool in the diagnosis, classification and monitoring of periodontal diseases. However, the role of circulating antibodies in periodontal patients is poorly understood. Patients suffering from localized juvenile periodontitis (LJP) are often reported to show high titers of serum IgG antibodies against Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans), but several affected patients do not. Most studies use well-known reference strains of the bacterium for testing against the patients' sera. The aim of the present investigation was to study the relationship between serum IgG antibody levels to autologous A. actinomycetemcomitans strains and clinical attachment loss (CAL). In addition, we wanted to assess the patients' serum titers against 4 well-known reference strains of the bacterium as well as their general potential immunoglobulin response. Intravenous blood samples were taken from 23 LJP patients and 10 healthy individuals, and autologous A. actinomycetemcomitans strains were cultured from 18 of the LJP patients. CAL was measured at 4 different sites around all present teeth and assessed as a % of teeth with at least 1 site moderately > or = 2 < 5 mm) or severely (> or = 5 mm) involved. An enzyme-linked immunosorbent assay (ELISA) was performed to evaluate the serum titers of IgG antibodies to A. actinomycetemcomitans antigens. No significant correlation was found between serum IgG antibody titers to autologous strains and CAL. However, there was a trend that low responders had more moderately affected teeth than had high responders and patients with undetectable A. actinomycetemcomitans levels, which is in agreement with a hypothetically protective role of the antibodies. The total counts of immunoglobulin assessed in all participants showed that the predominant class was IgG and the reference group displayed significantly less (p < 0.05) IgG and IgG1 counts than the LJP patients. Both the reaction pattern against reference and autologous strains varied widely. We conclude that the specific antibody response against A. actinomycetemcomitans shows a weak correlation to clinical attachment levels in LJP patients.     

Clinical and microbiological effects of adjunctive antibiotics in treatment of localized juvenile periodontitis. A controlled clinical trial

The aim of this study was to assess the clinical and microbiologic effects of the combination of amoxicillin and metronidazole therapy as an adjunct to mechanical treatment in the management of localized juvenile periodontitis. Twenty-five localized juvenile periodontitis (LJP) patients from a Brazilian population were randomly allocated into an experimental group receiving mechanical treatment and antibiotics, and a control group receiving mechanical treatment and placebo. Clinical and radiographic assessments, as well as microbiologic sampling for Actinobacillus actinomycetemcomitans, were performed at baseline and one year after the end of the treatment. At the termination of the study A. actinomycetemcomitans could be isolated from the oral cavity of all patients in the control group who harbored the bacterium at baseline and in 4 out of 8 patients in the experimental group. Both treatment modalities resulted in significant benefit on an individual basis. The experimental group, however, displayed better results than did the control group regarding gingival index (GI), probing depth (PD), clinical attachment level (CAL), and radiographic analysis of crestal alveolar bone mass, but not with respect to plaque index (PI). No serious adverse effects of the antibiotic treatment were observed in the present study.     

The relation of microbiologic data to aspartate aminotransferase enzyme activity in gingival crevicular fluid

Gingival crevicular fluid (GCF), reflects the immune and inflammatory reactions and is itself a location for specific host-microbe interactions that lead to periodontal diseases. Aspartate aminotransferase (AST) is one of the components of GCF that is released as a result of cell death. In this study, 40 periodontal sites in 10 early onset periodontitis patients before and after nonsurgical periodontal therapy, with and without local metronidazole administration, were first examined for the AST enzyme levels in GCF and then evaluated for microbiological and clinical variables. In each patient, 4 sites (one site/quadrant) with a probing depth of > or = 5 mm were selected and treated with separate treatment protocols. Certain microbial species including Prevotella intermedia, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans(A. a.) were found more often and/or in higher levels in AST active sites (36/40 first measurement--9/36 second measurement), while other species (Streptococcus and Actinomyces) were found more often and/or in higher levels in AST inactive sites (4/40 first measurement--8/36 second measurement). Eight post-treatment AST active sites revealed 1.5 mm of attachment loss, whereas 8 post-treatment AST inactive sites showed 1.37 mm of attachment gain. AST activity and microbiological-clinical data presenting such an agreement suggests that, AST level assessment would be beneficial as an adjunctive method alongside other clinical criteria, in guiding the clinician in periodontal treatment.     

Subgingival microflora and treatment in prepubertal periodontitis associated with chronic idiopathic neutropenia

Prepubertal periodontitis affects both primary and permanent dentition. The purpose of this study was to examine the composition of subgingival microflora of the permanent dentition in an 11-year-old Caucasian female, who had premature exfoliation of her deciduous teeth on her 5th year of age, and the response of this condition to the antibiotic therapy and supportive periodontal care. Gingival tissues were highly inflamed and alveolar bone loss was detected radiographically. The girl had experienced frequent upper respiratory tract infections, tonsilitis and recurrent otitis media. Her mother had history of early onset periodontitis associated with chronic idiopathic neutropenia. Blood chemistry tests and immunological examinations were also performed. Subgingival plaque samples were collected from the proximal sites of permanent molars, incisors, canines and maxillary premolars. 27 different microbial species were isolated from the subgingival microflora. Among the predominant species were Porphyromonas gingivalis (17.6%-7.3%), Prevotella intermedia (12.4%-4.7%), Capnocytophaga sputigena (14.4%-10.4%), Capnocytophaga ochracea (13.2%-6.9%) and Actinobacillus actinomycetemcomitans (9.3%-5.5%). Periodontal treatment consisted of scaling, root planing in conjunction with antibiotic administration of Augmentin 312.5 mg and Flagyl 200 mg, each t.i.d. for 10 days. 3 weeks after the antibiotic therapy, bacterial samples were collected from the same sites. All the periodontal pathogens were recovered in lower levels and A.actinomycetemcomitans was almost eliminated in the 3-week period. The evaluation of clinical indices at 3, 6 and 12 months showed that periodontal treatment in conjunction with antibiotics was effective and rapidly followed by marked clinical improvement. The microbiological monitoring at 3, 6 and 12 months after antibiotic treatment and each time prior to supportive periodontal care, revealed that the periodontal pathogens fluctuated in low levels even 12 months after treatment and could be maintained at low level by supportive periodontal care at 3-month intervals.     

Repopulation of periodontal pockets by microbial pathogens in the absence of supportive therapy

This clinical study evaluated the reinfection incidence by Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and Prevotella intermedia (Pi) in periodontal pockets following scaling and root planing (SRP) and intra-pocket irrigation with antimicrobial agents in a patient population who did not receive supportive maintenance therapy. The number of target organisms was determined utilizing DNA probes. Forty-one (41) inflamed pockets > or = 5 mm with attachment loss and containing at least one target species were selected in 6 adult patients. Following a baseline clinical and bacterial examination, all patients received thorough SRP. In addition, 1 to 2 teeth in each patient were randomly assigned to each of the following 4 treatment modalities: 1) control group, no irrigation; 2) saline group, irrigation with 2 cc of 0.85% saline; 3) tetracycline group, irrigation with 2 cc of aqueous tetracycline HCl, 50 mg/ml (5%); and 4) chlorhexidine group, irrigation with 2 cc, respectively. All selected sites were non-adjacent. No additional therapy was rendered during the entire 1-year observation period. Clinical parameters and microbial analyses were recorded again at 1 week, and 1, 3, 6, 9, and 12 months post-treatment. The effect of antimicrobial irrigation on the reinfection rate of sites by Aa, Pg, and Pi was compared with that of the control groups (1 and 2) by ANOVA. No statistically significant differences were observed among the irrigation treatment groups with regard to any of the clinical or bacterial parameters studied. Therefore, the 4 treatment groups were combined into a single group whereby the rate of bacterial repopulation following extensive scaling and root planing could be ascertained. The infection incidence of sites at baseline (of total sites), 1 week and 12 months (of sites originally infected at baseline) was 14/41, 3/14, and 7/14 for Aa; 33/41, 6/33, and 12/33 for Pg; and 37/41, 3/37, and 12/37 for Pi, respectively. Thus, half or fewer of the originally infected sites became reinfected at 12 months despite lack of maintenance therapy. The results suggest that 1) a single episode of pocket irrigation with antimicrobial agents following thorough scaling and root planing did not affect the rate of repopulation of periodontal pockets by the tested pathogens; 2) thorough scaling and root planing has a lasting suppressive effect on selected periodontal pathogens for the majority of sites in patients with adult periodontitis; 3) pre-operative probing depth, the amount of gingival fluid flow and the composition of the subgingival microflora may serve as predictors for reinfection in the absence of maintenance care; and 4) reinfection of the treated sites by Aa, Pg, and/or Pi may constitute a risk factor that diminishes the effect of therapy in the absence of supportive maintenance care.     

Overdose among youth in Bahrain: psycho-social characteristics, contact with helping agencies and problems

The in vitro minimal inhibitory concentrations (MIC) and minimal bactericidal concentration (MBC) of roxithromycin and erythromycin against Actinobacillus actinomycetemcomitans were evaluated. Sixty-seven different A. actinomycetemcomitans isolated from periodontal pockets of 101 subjects with different forms of early-onset and adult periodontitis and three reference strains of A. actinomycetemcomitans (ATCC 29522, ATCC 29523, and NCTC 9710) were included in this study. Erythromycin showed poor in vitro activity against A. actinomycetemcomitans; roxithromycin, on the contrary, exhibited good in vitro activity. Moreover, roxithromycin showed the best in vitro antimicrobial activity against 17 serotype a and 12 serotype c subpopulations of A. actinomycetemcomitans; against 38 serotype b subpopulation of A. actinomycetemcomitans, roxithromycin was consistently active. Roxithromycin exhibited MBC values usually equal to, or one-fold higher than MIC values. All the MBC values of erythromycin were three- to four-fold higher than the respective MIC result. Since roxithromycin is characterized by high concentrations in serum and good penetration and diffusion into gingival tissue, it could be expected to pass into the gingival crevicular fluid at levels sufficiently high to inhibit A. actinomycetemcomitans in vivo. These data indicate that roxithromycin might be a potential candidate for therapeutic trials in patients with A. actinomycetemcomitans-associated periodontitis.     

Role of intestinal transit in the pathogenesis of gallbladder stones

The aim of the study was to compare the occurrence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia in the subgingival plaque from sites with and without early periodontitis in adolescents using an ELISA. 47, 15- to 16-year-old adolescents (39 Indo-Pakistani, 8 white Caucasian) were examined for clinical attachment level, probing depth, supragingival plaque, subgingival calculus and bleeding on probing on the mesio-buccal and disto-buccal aspects of the 1st molars and the incisors. Based on the clinical data, 2 sites per subject were selected for subgingival plaque sampling 3 weeks later: in 32 subjects with loss of attachment > or = 1 mm, a diseased site (D) and a healthy comparison control site (C) were sampled; in 15 subjects in whom loss of attachment had not yet developed, 1 of the upper molar sites was selected, called the at-risk site (R), together with a C site. The presence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia were determined using an ELISA. The loss of attachment subgroup had significantly more pockets > or = 4 mm, subgingival calculus and bleeding on probing (p < 0.05). Significantly more of the D than C sites had P. gingivalis both at detectable and at measurable levels (p < 0.05). In subjects who had no loss in clinical attachment levels, fewer sampled sites harboured any of the suspected periodontopathogens investigated, and no significant differences were found between the R or C sites (p > 0.05). Although there was a significantly higher prevalence and extent of loss of attachment > or = 1 mm in the Indo-Pakistani subjects compared with the Caucasians (p < 0.05), no differences could be identified in the distribution of the bacteria. It is concluded that monitoring of the subgingival plaque may be useful in studies of early periodontitis in adolescents, and the role of P. gingivalis needs to be elucidated in prospective longitudinal investigations.     

28 K in squamous metaplasia of the bladder in patients with spinal cord injury

Actinobacillus actinomycetemcomitans has been strongly implicated in the etiology of localized juvenile periodontitis. Techniques used in the identification of this periodontal pathogen include cultural, biochemical, immunological and DNA hybridization analysis. In this study, we report the use of polymerase chain reaction (PCR) to amplify unique sequences of A. actinomycetemcomitans. Specific oligonucleotide primers LKT2 and LKT3 were designed to hybridize to the A. actinomycetemcomitans lktA gene, which encodes leukotoxin, a putative A. actinomycetemcomitans virulence factor. The LKT2 and LKT3 primers amplified lktA-specific sequences from all 12 A. actinomycetemcomitans strains tested. In another set of experiments, 13 other bacterial species, most of which are normal residents of the oral cavity, were tested with these primers. These PCR amplifications also contained 2 additional primers, RRN4 and RRN5, which served as positive controls; RRN4 and RRN5 were designed to amplify specific sequences of eubacterial 16S ribosomal DNA (rDNA). PCR amplifications of all bacterial species tested, including A. actinomycetemcomitans, yielded 16S rDNA-specific DNA fragments. Furthermore, each bacterial species tested, with the exception of A. actinomycetemcomitans, failed to amplify lktA sequences. The LKT and RRN primers were used in further PCR experiments to detect A. actinomycetemcomitans directly from gingival fluid samples. The results clearly demonstrate the simplicity, rapidity, specificity and accuracy of the LKT primers in the identification of A. actinomycetemcomitans.     

Infusion therapy with milrinone in the home care setting for patients who have advanced heart failure

The pathogenicity of 14 isolates identified as Prevotella intermedia or Prevotella nigrescens by serogrouping using monoclonal antibodies was compared in a tissue cage model in rabbits. Seven strains from periodontal abscesses, 5 strains from deep periodontal pockets and 2 strains from gingivitis were tested in the animal model comprising 6 Teflon tissue cages implanted on the back each of 34 rabbits. A total of 10(5)-10(8) cells of P. intermedia or P. nigrescens strains were inoculated alone or together with either Actinobacillus actinomycetemcomitans or Streptococcus mitis. Five strains of Porphyromonas gingivalis were used as a reference. The infectivity was recorded as pus formation and log viable count in aspirated material for 3, 7 and 14 days. None of the Prevotella strains inoculated in monoculture survived more than 3 days, and they had no capacity to produce abscess. P. intermedia or P. nigrescens strains in combination with A. actinomycetemcomitans produced abscesses in 33-100% and with S. mitis in 42-100%. No difference in abscess formation or log viable count in samples after 14 days was recorded between serogroup I (P. intermedia) and serogroup II and III (P. nigrescens). The infectivity of P. intermedia or P. nigresceas strains did not differ whether they were isolated from periodontal abscess, periodontal pocket or gingivitis. P. intermedia and P. nigrescens strains produced abscesses in combination with a facultative anaerobic strain and appears to have a similar pathogenicity in the wound chamber model in rabbits.     

Effects of treatment on antibody titer to Porphyromonas gingivalis in gingival crevicular fluid of patients with rapidly progressive periodontitis

Twenty-eight patients diagnosed as having rapidly progressive periodontitis (RPP) were enrolled in a study in which samples of subgingival microflora were harvested from test teeth and assayed for the presence of Porphyromonas gingivalis, and GCF collected and analyzed by ELISA for specific antibody for P. gingivalis. Clinical conditions were measured and recorded, and treatment by scaling and root planing provided at baseline and at 3, 6, 9, and 12 months. Reduction in pocket depth, stabilization of attachment level, and resolution of inflammation were comparable to previously reported values. By 3 months, mean and median specific antibody concentration had decreased, and continued to decrease through 12 months. The proportion of samples in which specific antibody was not detectable increased from 27% at baseline to 73% at month 12. GCF samples from sites at which P. gingivalis was present had greater than 2-fold higher median specific antibody than samples from P. gingivalis-negative sites. At baseline, specific antibody titer of 30-second GCF samples positively correlated with pocket depth, and GCF volume significantly correlated with antibody titer and concentration, and with pocket depth. In addition, change in specific antibody titer of 30-second samples from baseline to both 6 and 12 months correlated positively with pocket depths. Thus sites infected by P. gingivalis manifested high levels of specific antibody, and levels were related to clinical status. Following treatment, antibody levels decreased significantly as pocket depths decreased, attachment levels stabilized, and inflammation resolved.