Microbiology in diagnosis and treatment of severe periodontitis. A report of four cases

Clinical laboratory diagnostics in dentistry: Application of microbiological methods

Diagnosis and treatment in dentistry are based on clinical examination of the patients. Given that the major oral diseases are of microbial biofilm etiology, it can be expected that performing microbiological analysis on samples collected from the patient could deliver supportive evidence to facilitate the decision-making process by the clinician. Applicable microbiological methods range from microscopy, to culture, to molecular techniques, which can be performed easily within dedicated laboratories proximal to the clinics, such as ones in academic dental institutions. Periodontal and endodontic infections, along with odontogenic abscesses, have been identified as conditions in which applied clinical microbiology may be beneficial for the patient. Administration of antimicrobial agents, backed by microbiological analysis, can yield more predictable treatment outcomes in refractory or early-occurring forms of periodontitis. Confirming a sterile root canal using a culture-negative sample during endodontic treatment may ensure the longevity of its outcome and prevent secondary infections. Susceptibility testing of samples obtained from odontogenic abscesses may facilitate the selection of the appropriate antimicrobial treatment to prevent further spread of the infection.

Clinical, microbiological, and immunological effects of systemic probiotics in periodontal treatment: study protocol for a randomized controlled trial

BACKGROUND

The association of scaling and root planing (SRP) with systemic metronidazole (MTZ) plus amoxicillin (AMX) has shown to be an effective treatment protocol, particularly for periodontitis stages III and IV, generalized. More recently, probiotics have also been suggested as a promising adjunctive treatment for periodontal diseases due to their antimicrobial and anti-inflammatory properties. Therefore, the aim of this randomized clinical trial (RCT) is to evaluate the clinical, microbiological, and immunological effects of probiotics as adjuncts to SRP alone or with MTZ+AMX in the treatment of periodontitis.

METHODS

Subjects with periodontitis are being randomly assigned to receive (i) SRP alone, or with (ii) two probiotic lozenges/day for 90 days (Prob), (iii) MTZ (400 mg) and AMX (500 mg) thrice a day (TID) for 14 days (MTZ+AMX), or (iv) Prob and MTZ+AMX. Subjects are being monitored for up to 12 months post-treatment. Nine subgingival plaque samples per patient are being collected at baseline and at 3, 6, and 12 months post-therapy and analyzed by checkerboard DNA-DNA hybridization for 40 bacterial species. Peripheral blood and gingival crevicular fluid (GCF) of four randomly selected periodontal sites will be analyzed by means of a multiplex fluorescent bead-based immunoassay for 17 cyto/chemokines.

STATISTICAL ANALYSES

The significance of differences in each group (over the course of the study) will be sought using repeated measures ANOVA or Friedman tests and among groups (at each time point) using either ANOVA/ANCOVA or Kruskal-Wallis tests, depending on normality of the data. The chi-square test will be used to compare differences in the frequency of subjects achieving the clinical endpoint for treatment (≤ 4 sites with PD ≥ 5 mm) at 1 year and of self-perceived adverse effects. A stepwise forward logistic regression analysis will be performed in order to investigate the impact of different predictor variables on the percentage of patients achieving the clinical endpoint for treatment. The Number Needed to Treat (NNT) with different treatment protocols will be also calculated. Statistical significance will be set at 5%.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03733379. Registered on November 7, 2018.

Did Omics change periodontal therapy?

The starting point for defining effective treatment protocols is a clear understanding of the etiology and pathogenesis of a condition. In periodontal diseases, this understanding has been hindered by a number of factors, such as the difficulty in differentiating primary pathogens from nonpathogens in complex biofilm structures. The introduction of DNA sequencing technologies, including taxonomic and functional analyses, has allowed the oral microbiome to be investigated in much greater breadth and depth. This article aims to compile the results of studies, using next-generation sequencing techniques to evaluate the periodontal microbiome, in an attempt to determine how far the knowledge provided by these studies has brought us in terms of influencing the way we treat periodontitis. The taxonomic data provided, to date, by published association and elimination studies using next-generation sequencing confirm previous knowledge on the role of classic periodontal pathogens in the pathobiology of disease and include new species/genera. Conversely, species and genera already considered as host-compatible and others less explored were associated with periodontal health as their levels were elevated in healthy individuals and increased after therapy. Functional and transcriptomic analyses also demonstrated that periodontal biofilms are taxonomically diverse, functionally congruent, and highly cooperative. Very few interventional studies to date have examined the effects of treatment on the periodontal microbiome, and such studies are heterogeneous in terms of design, sample size, sampling method, treatment provided, and duration of follow-up. Hence, it is still difficult to draw meaningful conclusions from them. Thus, although OMICS knowledge has not yet changed the way we treat patients in daily practice, the information provided by these studies opens new avenues for future research in this field. As new pathogens and beneficial species become identified, future randomized clinical trials could monitor these species/genera more comprehensively. In addition, the metatranscriptomic data, although still embryonic, suggest that the interplay between the host and the oral microbiome may be our best opportunity to implement personalized periodontal treatments. Therapeutic schemes targeting particular bacterial protein products in subjects with specific genetic profiles, for example, may be the futuristic view of enhanced periodontal therapy.

Microbial colonization of the periodontal pocket and its significance for periodontal therapy

The aim of this paper was to evaluate strategies for periodontal therapy from the perspective of periodontal disease being a consequence of microbial colonization of the periodontal pocket environment. In classic bacterial infections the diversity of the microbiota decreases as the disease develops. In most cases of periodontitis, however, the diversity of the flora increases. Most incriminating bacteria are thought to harm tissues significantly only if present in high numbers over prolonged periods of time. Clinical trials have repeatedly demonstrated that scaling and root planing, a procedure that aims to remove subgingival bacterial deposits by scraping on the tooth surface within the periodontal pocket, is effective. At present, for the therapy of any form of periodontal disease, there exists no protocol with proven superiority, in terms of efficiency or effectiveness, over scaling and root planing plus systemic amoxicillin and metronidazole. Some exponents advocate rationing these drugs for patients with a specific microbial profile. However, the evidence for any benefit of bacteriology-assisted clinical protocols is unsatisfactory. Treated sites are subject to recolonization with a microbiota similar to that present before therapy. The degree and speed of recolonization depends on the treatment protocol, the distribution patterns of periodontal microorganisms elsewhere in the oral cavity and the quality of the patient's oral hygiene. To limit the use of antibiotics and to avoid accumulation of harmful effects by repeated therapy, further efforts must be made to optimize procedures addressing the microbial colonization and recolonization of the periodontal pocket.

Efficacy of Natural and Allopathic Antimicrobial Agents Incorporated onto Guided Tissue Regeneration Membrane Against Periodontal Pathogens: An in vitro Study

INTRODUCTION

Periodontal disease is one of the most prevalent afflictions worldwide. It is an infection of the periodontium as a result of subgingival colonization of the specific microbiota, leading to loss of attachment, which requires optimal care for regeneration to its pre-disease state. Guided Tissue Regeneration (GTR) is one of the successful treatment modalities in Periodontal Regenerative Therapy, but is vulnerable to bacterial colonization. The conflict between usage of classical antibiotics and plant origin antimicrobial agents has recently been in the limelight.

AIM

The aim of this study was to assess the in vitro antimicrobial activity of amoxicillin, metronidazole and green coffee extract loaded onto GTR membrane against periodonto-pathogens.

MATERIALS AND METHODS

Pure form of amoxicillin, metronidazole and green coffee extract were obtained. One percent concentration of each antimicrobial agent was prepared by appropriate dilution with distilled water. GTR membrane was cut into a size of 1x0.5 cm under sterile conditions and was coated with the antimicrobial agents respectively and with distilled water as the negative control. Antimicrobial activity was checked against Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) and Porphyromonas gingivalis (P. gingivalis) using agar disc diffusion method. The statistical analysis was done using Kruskal Wallis ANOVA and Mann-Whitney U test.

RESULTS

One percent amoxicillin showed level of significance (p>0.05) against both A. actinomycetemcomitans and P. gingivalis. Green coffee extract showed no zone of inhibition against both the bacterial species.

CONCLUSION

Loading of commercially available antimicrobial agents onto GTR membrane can prevent its bacterial colonization leading to better treatment outcomes for periodontal regeneration.

Clinical and microbiological effects of systemic azithromycin in adjunct to nonsurgical periodontal therapy in treatment of Aggregatibacter actinomycetemcomitans associated periodontitis: a randomized placebo-controlled clinical trial

OBJECTIVE

This study aimed to evaluate clinical and microbiological effects of systemic azithromycin (AZM) in adjunct to nonsurgical periodontal therapy (NSPT; or scaling root planing - SRP) in treatment of Aggregatibacter actinomycetemcomitans associated periodontitis (AAAP).

METHODS AND MATERIALS

Seventy individuals with moderate to severe periodontitis and subgingival detection of A. actinomycetemcomitans were randomly allocated to two groups. Thirty-five individuals were allocated to full mouth SRP+AZM (500 mg oral delivery (OD) × 3 days) while 35 individuals were allocated to SRP+Placebo (OD × 3 days) group. The clinical variables evaluated were probing depth (PD), clinical attachment level (CAL), gingival index (GI), plaque index (PI), and percent bleeding on probing sites (%BOP), while microbiologic variables included percentage of subjects positive for A. actinomycetemcomitans at baseline, 3, 6, and 12 months.

RESULTS

The AZM group showed statistically significant reduction in mean PD (2.91 ± 0.88 mm) as compared to placebo (1.51 ± 0.98 mm) (P < 0.001), while CAL gain was significant in the AZM group (2.71 ± 1.15 mm) as compared to the placebo group (1.71 ± 1.29 mm) (P < 0.001). There was also a statistically significant reduction in the number of subjects positive for A. actinomycetemcomitans in the AZM group (P < 0.0001).

CONCLUSION

Azithromycin was found to significantly improve the clinical and microbiological parameters in AAAP individuals.

Case definitions for use in population-based surveillance of periodontitis

Many definitions of periodontitis have been used in the literature for population-based studies, but there is no accepted standard. In early epidemiologic studies, the two major periodontal diseases, gingivitis and periodontitis, were combined and considered to be a continuum. National United States surveys were conducted in 1960 to 1962, 1971 to 1974, 1981, 1985 to 1986, 1988 to 1994, and 1999 to 2000. The case definitions and protocols used in the six national surveys reflect a continuing evolution and improvement over time. Generally, the clinical diagnosis of periodontitis is based on measures of probing depth (PD), clinical attachment level (CAL), the radiographic pattern and extent of alveolar bone loss, gingival inflammation measured as bleeding on probing, or a combination of these measures. Several other patient characteristics are considered, and several factors, such as age, can affect measurements of PD and CAL. Accuracy and reproducibility of measurements of PD and CAL are important because case definitions for periodontitis are based largely on either or both measurements, and relatively small changes in these values can result in large changes in disease prevalence. The classification currently accepted by the American Academy of Periodontology (AAP) was devised by the 1999 International Workshop for a Classification of Periodontal Diseases and Conditions. However, in 2003 the Centers for Disease Control and Prevention and the AAP appointed a working group to develop further standardized clinical case definitions for population-based studies of periodontitis. This classification defines severe periodontitis and moderate periodontitis in terms of PD and CAL to enhance case definitions and further demonstrates the importance of thresholds of PD and CAL and the number of affected sites when determining prevalence.

'Interleukin-4 gene polymorphism and its relation to periodontal disease in a Brazilian population of African heritage'

OBJECTIVES

Host modifying factors, such as genetic predisposition, may increase severity of periodontitis. Genetic polymorphisms in interleukin-4 (IL-4) genes seem to influence host response to microbial challenge. Two IL-4 polymorphisms were found in association with asthma and atopy, and later with aggressive periodontitis in Caucasians. There seems to be a trend for racial differences regarding polymorphisms. Therefore, this study aimed to evaluate if these IL-4 polymorphisms were associated with periodontal disease in a Brazilian population of African heritage.

METHODS

Sixty patients were divided into two groups: periodontitis group (n = 30) and control group (n = 30) Blood samples were taken and genomic DNA was amplified by polymerase chain reaction (PCR). Identification of 70 bp repeat polymorphism in intron 2 and in the -590 position of the promoter region was performed through PCR-RFLP and electrophoresis in agarose gel.

RESULTS

No significant differences were found in the genotype frequency of the polymorphisms between control and periodontitis group. Chi square test and Mann-Whitney test were used for statistical analysis.

CONCLUSIONS

We concluded that the studied IL-4 polymorphisms were not related to periodontal disease susceptibility in this African-American Brazilian population.

Topical and systemic antibiotics in the management of periodontal diseases

Both systemic and topical antibiotics are increasingly used in the management of periodontal infections. Whilst these drugs are used mostly on an empirical basis, some contend that rational use of antibiotics should be the norm due to their wide abuse and consequential global emergence of antibiotic resistance organisms. Here we review the rationale and principles of antimicrobial therapy, treatment goals, drug delivery routes and various antibiotics that are used in the management of periodontal diseases. The pros and cons of systemic and local antibiotic therapy are described together with practical guidelines for their delivery. The available data indicate, in general, that mechanical periodontal treatment alone is adequate to ameliorate or resolve the clinical condition in most cases, but adjunctive antimicrobial agents, delivered either locally or systemically, can enhance the effect of therapy in specific situations. This is particularly true for aggressive (early onset) periodontitis, in patients with generalised systemic disease that may affect host resistance and in case of poor response to conventional mechanical therapy. Locally delivered antibiotics together with mechanical debridement are indicated for non-responding sites of focal infection or in localised recurrent disease. After resolution of the periodontal infection, the patient should be placed on an individually tailored maintenance care programme. Optimal plaque control by the patient is of paramount importance for a favourable clinical and microbiological response to any form of periodontal therapy.

Systemic antimicrobials in the treatment of chronic periodontal diseases: a dilemma

The use of systemic antimicrobials in the treatment of acute and chronic periodontal diseases must be viewed as a dilemma. On the one hand, the approach is attractive because of the microbial nature of periodontal diseases but, on the other hand, evidence of benefit of these agents is equivocal for the majority of periodontal diseases and antimicrobials have the potential to cause harm. The disadvantages of systemic antimicrobials can be grouped under the headings of allergic reactions, superinfection, toxicity, drug interactions, patient compliance and, perhaps of most widespread importance, bacterial resistance. Mechanical debridement methods, including drainage of pus for acute periodontal abscesses, should be considered the first line treatment for most periodontal diseases. Systemic antimicrobials should be considered as adjuncts to mechanical debridement methods and, in chronic disease, never used alone as they can predispose to abscess formation. Adjunctive systemic antimicrobials may be considered in acute disease where debridement or drainage of pus is difficult, where there is local spread or systemic upset. In chronic periodontal diseases, adjunctive antimicrobials should be considered in early onset or rapidly progressive disease or in advanced chronic adult disease where mechanical therapies have failed or surgery is not a preferred option. Inadequate oral hygiene and tobacco smoking are contraindications to the use of antimicrobials. The value of systemic antimicrobials, where other systemic risk factors co-exist, has still to be established. The role of microbial diagnosis and sensitivity testing for antimicrobial selection at this time must be questioned.

Adjunctive effects to non-surgical periodontal therapy of systemic metronidazole and amoxycillin alone and combined. A placebo controlled study

BACKGROUND AND AIM

Several studies have reported adjunctive benefits to scaling and root planing (SRP) of systemic amoxycillin and metronidazole in the treatment of periodontal diseases. To date no comparisons have been made of these antimicrobials alone or in combination. The aim of this study was to compare the adjunctive benefits to SRP of amoxycillin and metronidazole alone and combined.

METHODS

66 subjects <46 years of age with advanced chronic periodontal disease participated in this randomised, double blind, 4 parallel treatment group designed study. All subjects received quadrant SRP and then were prescribed amoxycillin capsules (250 mg) and metronidazole tablets (200 mg) (AM) or lactate capsules and metronidazole (PM) or amoxycillin and calcium lactate tablets (AP) or lactate and calcium lactate (PP). All medication was 3 of each per day for 7 days. Subgingival plaque samples were obtained and probing depth (PD), loss of attachment (LOA), bleeding on probing (BOP), suppuration (SUPP) and plaque (DEP) were recorded pre-treatment, 1, 3 and 6 months post-treatment.

RESULTS

Final group sizes were: AM=15, PM=16, AP=16 and PP=15. PD improved in all groups. Treatment effects were highly significantly different and always greatest in the AM and least in the PP groups. Benefits of PM and AP over PP were also noted. LOA improved in all groups and showed the same highly significant treatment differences, again favouring AM. BOP improved in all groups, particularly in AM compared to the other groups. SUPP improved in all groups and was virtually eradicated in AM with differences among treatments highly significant. DEP changed little in any group and there were no significant differences among groups. Microbiological data showed significant differences in favour of AM compared to PP and PM for total aerobes and anaerobes at 1 month. P. intermedia counts were always lower in active groups compared to PP and reached significance for AM and AP at 1 month and AM and PM at 3 months.

CONCLUSION

The significant differences among treatment groups and the overall trend in the data, in line with other studies, support the considerable adjunctive benefits to SRP of amoxycillin and metronidazole combined in the treatment of advanced chronic periodontal disease.

How do data from deepest pocket per quadrant relate to full-mouth scores? Progression of untreated periodontal disease in young Indonesians

BACKGROUND

When the subgingival presence of periodontal pathogens is studied in groups of patients or populations, mostly a number of the deepest sites is sampled. The mean clinical parameters of these deep sites are also frequently used as a the descriptor of the clinical situation of these subjects. It can be questioned, whether these 4 deep sites are capable of predicting a full-mouth situation.

AIM

The purpose of the present retrospective study was to investigate to what extent the experienced progression of periodontitis as measured in the deepest approximal pocket in each quadrant reflects the disease progression at the approximal sites on a full-mouth level.

METHODS

A data set of a 7-year longitudinal study of 158 young subjects (69 male, 89 female, 15-25 years of age at baseline) was used. Clinical assessments included plaque index (PI), pocket depth (PD) and attachment loss (AL) at baseline (1987) and follow-up (1994). Measurements were made at the approximal surfaces of all teeth. The deepest pocket in each quadrant was determined at follow-up. Changes of the clinical parameters between baseline and follow-up were calculated both as full-mouth mean scores as well as for these 4 deepest sites. A regression analysis was used to evaluate the relationship between full-mouth score and the 4 test sites.

RESULTS

For disease progression between baseline and follow-up, significant correlation coefficients were observed between the 4-site and full-mouth mean changes (PD: 0.80, AL: 0.70, PI: 0.77). Regression coefficients were 0.51 for PD, 0.35 for AL and 0.55 for PI. The precision of the estimate for the full-mouth mean, as predicted by the 4-site mean, is determined by the residual standard deviation. This was for PD 0.31 mm, for AL 0.31 mm and for PI 0.29. Compared to the between-patient standard deviation of the full-mouth means, the residual standard deviations were high.

CONCLUSION

In the present population, a reasonable to good correlation between full-mouth and 4-sites data was observed. However, the high residual standard deviation in the regression analysis illustrates the inaccuracy for the 4-sites data when used as a descriptive for changes in the periodontal condition on a full-mouth level. Data evaluating progression of periodontitis based on a limited number of diseased sites should be interpreted cautiously.

Clinical usefulness of microbiological diagnostic tools in the management of periodontal disease

Periodontal diseases comprises a group of chronic inflammatory conditions affecting tooth supporting structures. It has been known for a long time that pathogenic oral bacteria colonizing the tooth surface are associated with the initiation of the disease process. However, to date, a dozen or so bacterial species have been implicated in the pathogenesis of periodontal disease and no one species by itself is synonymous with disease onset. This multibacterial etiology renders the diagnosis of active periodontal disease based on microbiological data difficult. Numerous studies have attempted to relate the usefulness of microbiological diagnostic aids such as microscopy, bacterial culture, immunological and enzymatic assays. Furthermore, recent technical advances have resulted in the use of nucleic acid probes and amplification techniques for the identification of genetic material belonging to potential periodontal pathogens. Despite the availability of a large number of microbiological testing protocols, identification of the microbial etiological agents remains hampered by the complexity of the microbial challenge during periodontal disease. This review discusses the clinical usefulness of these tests in detection and management of periodontal disease.

Amoxicillin plus metronidazole in the treatment of adult periodontitis patients. A double-blind placebo-controlled study

BACKGROUND, AIMS

The aim of this double-blind, parallel study was to evaluate the adjunctive effects of systemically administered amoxicillin and metronidazole in a group of adult periodontitis patients who also received supra- and subgingival debridement.

METHODS

49 patients with a diagnosis of generalised severe periodontitis participated in the study. Random assignment resulted in 26 patients in the placebo (P) group with a mean age of 40 years and 23 patients in the test (T) group which had a mean age of 45 years. Clinical measurements and microbiological assessments were taken at baseline and 3 months after completion of initial periodontal therapy with additional placebo or antibiotic treatment. Patients received coded study medication of either 375 mg amoxicillin in combination with 250 mg metronidazole or identical placebo tablets, every 8 hours for the following 7 days.

RESULTS

At baseline, no statistically significant differences between groups were found for any of the clinical parameters. Except for the plaque, there was a significantly larger change in the bleeding, probing pocket depth (PPD) and clinical attachment level (CAL) in the T-group as compared to the P-group after therapy. The greatest reduction in PPD was found at sites with initial PPD of > or = 7 mm, 2.5 mm in the P-group and 3.2 mm in the T-group. The improvement in CAL was most pronounced in the PPD category > or = 7 mm and amounted to 1.5 mm and 2.0 mm in the P- and T-groups, respectively. No significant decrease was found in the number of patients positive for any of the test species in the P-group. The number of patients positive for Porphyromonas gingivalis, Bacteroides forsythus and Prevotella intermedia in the T-group showed a significant decrease. After therapy there was a significant difference between the P- and the T- group in the remaining number of patients positive for P. gingivalis, B. forsythus and Peptostreptococcus micros. 4 subgroups were created on the basis of the initial microbiological status for P. gingivalis positive (Pg-pos) and negative patients (Pg-neg) in the P- and the T-groups. The difference in reduction of PPD between Pg-pos and Pg-neg patients was particularly evident with respect to the changes in % of sites with a probing pocket depth > or = 5 mm. This % decreased from 45% at baseline to 23% after treatment in the Pg-pos placebo subgroup and decreased from 46% to 11% in the Pg-pos test subgroup (p < or = 0.005). In contrast, the changes in the proportions of sites with a probing pocket depth > or = 5 mm in the Pg-neg placebo and Pg-neg test subgroup were similar, from 43% at baseline to 18% after treatment versus 40% to 12% respectively.

CONCLUSIONS

This study has shown that systemic usage of metronidazole and amoxicillin, when used in conjunction with initial periodontal treatment in adult periodontitis patients, achieves significantly better clinical and microbiological results than initial periodontal treatment alone. Moreover, this research suggests that especially patients diagnosed with P. gingivalis benefit from antibiotic treatment.

The antimicrobial treatment of periodontal disease: changing the treatment paradigm

Over the last 100 years, methods of surgical periodontal treatment have enjoyed a history of success in improving oral health. The paradigm of care is based on the "non-specific plaque hypothesis"--that is, the overgrowth of bacterial plaques cause periodontal disease, and the suppression of this overgrowth reduces disease risk. The central feature of this approach to care is the removal of inflamed gingival tissue around the teeth to reduce periodontal pocket depth, thereby facilitating plaque removal by the dentist and by the patient at home. Over the last 30 years, with the recognition that periodontal disease(s) is caused by specific bacteria and that specific antimicrobial agents can reduce or eliminate the infection, a second paradigm has developed. This new paradigm, the "specific plaque hypothesis", focuses on reducing the specific bacteria that cause periodontal attachment loss. The contrast between the two paradigms can be succinctly stated as follows: The antimicrobial therapy reduces the cause, while the surgical therapy reduces the result of the periodontal infection. The specific plaque hypothesis has two important implications. First, with the increasing attention to evidence-based models for prevention, treatment, outcome assessment, and reimbursement of care, increasing attention and financial effort will be channeled into effective preventive and treatment methods. Second, the recent observations that periodontal infections increase the risk of specific systemic health problems, such as cardiovascular disease, argue for the prevention and elimination of these periodontal infections. This review highlights some of the evidence for the specific plaque hypothesis, and the questions that should be addressed if antimicrobial agents are to be used responsively and effectively.

Fluoroquinolones in the treatment of Actinobacillus actinomycetemcomitans-associated periodontitis

BACKGROUND

Periodontitis patients harboring Actinobacillus actinmycetemcomitans (Aa) are prime candidates for systemic antibiotic therapy. Besides tetracycline and the combination of metronidazole and amoxicillin the fluoroquinolones are also believed to have antibacterial activity against Aa. The aim of the present study was to evaluate systemic ofloxacin therapy as adjunct to flap surgery.

METHODS

Twenty-five adult periodontitis patients with subgingival detection of Aa were treated with 2x200 mg/d ofloxacin for 5 days as adjunct to open flap surgery (test). Another 10 patients received only flap surgery (control). Probing depth (PD) and clinical attachment level (CAL) was recorded and subgingival plaque samples were cultivated on TSBV agar for detection of Aa at baseline as well as 3 and 12 months following therapy.

RESULTS

At 3 and 12 months following therapy mean PD at monitored sites in the test group changed from 6.8 mm (+/-1.3) to 3.6 mm (+/-1.0), 3.8 mm (+/-1.1) and CAL from 7.5 mm (+/-1.4) to 5.4 mm (+/-1.4), 5.5 mm (+/-1.3). In the control group PD changed from 6.5 mm (+/-0.7) to 4.0 mm (+/-1.7), 4.1 mm (+/-1.6) and CAL from 7.5 mm (+/-1.0) to 6.3 mm (+/-1.7), 6.4 mm (+/-1.8). P was <0.05 for CAL between groups. Three and 12 months following adjunctive systemic ofloxacin therapy, Aa was suppressed below detectable levels in 22 of 22, test patients, whereas Aa could not be recovered in only 2 of the 10 controls. (P<0.0001).

CONCLUSIONS

Systemic ofloxacin as adjunct to open flap surgery is able to suppress A. actinomycetemcomitans below detectable level in patients harboring this organism at baseline.

Repeated metronidazole and amoxicillin treatment of periodontitis. A follow-up study

BACKGROUND

The prevailing concept is that little or no clear benefit is derived from antibiotic therapy in chronic periodontitis. Studies to determine the effect of metronidazole plus amoxicillin (M+A) on adult periodontitis are questionable because standard design for clinical trials was usually not used. In addition, there is no information about the effect of M+A as the sole therapy for periodontitis.

METHODS

A randomized, triple-blind, controlled clinical trial was used to determine the effect of systemic administration of M+A, as the sole therapy, in progressive adult periodontitis. Forty-six subjects with moderate to advanced adult periodontitis who showed > or =2 mm attachment loss in at least 2 sites in the previous 2 months were entered in the study. Subjects were randomly distributed to a group who received 21 tablets of metronidazole 250 mg plus amoxicillin 500 mg, or to a group receiving a placebo (1 tablet every 8 hours for 1 week). Patients were examined every 2 months for 12 months. The M+A or placebo regimen was repeated at 4 and 8 months. No effort was made to change the oral habits of patients and they received no additional therapy. Differences between groups were assessed using the Mann-Whitney U test. The differences at every 2-month interval within each group were assessed using the ANOVA test.

RESULTS

Seven subjects abandoned the study; at 12 months the M+A group had 20 subjects and the placebo group 19. There were no significant differences in the clinical parameters at baseline between the 2 groups. After 2 months and thereafter, the M+A group showed significant clinical improvement while the placebo group showed a progressive deterioration of periodontal status. At 12 months compared to baseline, subjects of the M+A group showed: 1) a significant overall mean attachment gain of 0.43 mm (P = 0.005); 2) a significant decrease of active sites (P< or =0.03); 3) a significant increase of sites gaining attachment level (P< or =0.01); 4) a significant reduction of pocket depth (P< or =0.00006); and 5) a significant decrease in percentage of bleeding on probing sites (BOP) (P< or =0.0005). Significant differences between both groups at all 2-month evaluations were found in overall mean attachment level (P < or =0.000004), in percent of active sites (P< or =0.03), and in percent of BOP sites (P< or =0.02). Sites exhibiting > or =2 mm of attachment loss in 2 successive or alternate evaluations, and periodontal abscess were noticed only in the placebo group.

CONCLUSIONS

A 1-week course of systemic M+A every 4 months, as the only therapy, arrests the progression of adult periodontitis and significantly improves the clinical parameters of the disease.

Effect of initial periodontal therapy on the frequency of detecting Bacteroides forsythus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans

BACKGROUND

Porphyromonas gingivalis, Bacteroides forsythus, and Actinobacillus actinomycetemcomitans have been described as periodontopathic bacteria, and their presence in subgingival pockets can lead to development of periodontal disease. Until now, clinical parameters have been used to evaluate the effect of conventional periodontal treatment without microbiological parameters. The present study examined the microbiological effects of initial periodontal therapy using DNA probes and the polymerase chain reaction (PCR).

METHODS

Twenty-six patients with periodontitis, 10 males and 16 females, were given instructions regarding oral hygiene, then thoroughly treated by conventional scaling and root planing. Bacterial samples were collected on paper points from 4 sites per patient at baseline and after initial therapy (total: 104 sites). Clinical parameters including probing depth, attachment level, and bleeding on probing were also recorded for each site at baseline and after therapy. A DNA probe kit was used to monitor the frequency of B. forsythus, P. gingivalis, and A. actinomycetemcomitans, the last of which was identified by PCR.

RESULTS

At baseline, B. forsythus was the bacterium most frequently detected. DNA probe analysis also showed that more than half of the sites were colonized by both B. forsythus and P. gingivalis. Initial therapy resulted in significant clinical improvement such as significant reduction in the frequency of B. forsythus and P. gingivalis detected using the DNA probe. A. actinomycetemcomitans was difficult to detect using the DNA probe, but PCR indicated that levels of A. actinomycetemcomitans did not significantly decrease.

CONCLUSIONS

These results indicate that initial conventional therapy can eliminate B. forsythus and P. gingivalis, but not A. actinomycetemcomitans. When levels of these bacteria decreased to below-detectable levels, clinical improvement was significant. These results indicate that monitoring levels of these three periodontopathic bacteria may render periodontal therapy more effective and accurate.

Additional clinical and microbiological effects of amoxicillin and metronidazole after initial periodontal therapy

The aims of this study were to evaluate the clinical and microbiological effects of initial periodontal therapy (IT) and to determine the additional effects of systemic amoxicillin (Flemoxin Solutab) 375 mg TID plus metronidazole 250 mg TID therapy, in patients with adult Actinobacillus actinomycetemcomitans (Aa)-associated periodontitis in conjunction with either Porphyromonas gingivalis (Pg), Bacteroides forsythus (Bf) and/or Prevotella intermedia (Pi). In addition the adverse effects of the antimicrobial therapy were also documented. A total of 22 patients were enrolled. The deepest, bleeding pocket in each quadrant was selected and at these 4 experimental sites clinical measurements and microbiological testing was carried out at baseline, after (IT), i.e., 21 weeks after baseline, and after antimicrobial therapy (AM), i.e., 35 weeks after baseline. At baseline, the mean plaque index (PI) amounted 0.5, 0.1 after IT and 0.3 after systemic AM. The mean bleeding index decreased from 1.6 to 1.2 after IT and a further decrease to 0.7 after AM was noted. Suppuration was completely eliminated after AM. The mean change of probing pocket depth (PPD) after IT amounted 1.4 mm and was further reduced with an additional mean change of 1.1 mm after medication. Clinical attachment gain was 1.1 mm after IT and an additional 0.9 mm was observed after AM. One of the 22 Aa positive patients and 4 of 17 Pg positive patients became negative for these species after IT. The number of patients with detectable Pi decreased from 16 to 10 after IT. After AM, in comparison to baseline, suppression below detection level for Aa was achieved in 19 out of 22, for Pg in 9 out of 17, for Bf in 13 out of 14, and for Pi in 11 out of 16 patients. By contrast, higher frequencies of Peptostreptococcus micros and Fusobacterium nucleatum were found after AM. On the basis of the microbiological results the study group was separated into 2 subgroups: group A consisted of subjects who had no detectable levels of Aa, Pg, Bf and <5% of Pi after AM. Group B consisted of those who still showed presence of one of these 3 species and/or > or =5% levels of Pi. After AM, group B had significantly higher PI, BI, PPD and CAL scores then group A. It is concluded that group A showed low plaque scores and no detectable periodontal pathogens. This microbiological condition has been associated with a long-term stable periodontium.

Clinical and antimicrobial effects of a single episode of subgingival irrigation with tetracycline HCl or chlorhexidine in deep periodontal pockets

15 adults, each providing 4 non-adjacent untreated periodontal pockets with a probing depth (PD) exceeding 6 mm, volunteered for a randomized, split-mouth, double-blind, clinical study evaluating subgingival irrigation with chlorhexidine (CHX) or tetracycline HCl (TTC). The study protocol included oral hygiene instructions followed by scaling and root planing. Experimental and immediately adjacent teeth did not receive instrumentation. The 4 deep periodontal pockets in each patient were assigned to be irrigated with 150 ml CHX (0.12%), TTC (10 or 50 mg/ml; TTC10, TTC50), or sterile saline (control) in a single episode. Post-irrigation mechanical plaque control was supported by 2x daily CHX rinses throughout the 12-week observation interval. Recordings of oral hygiene (P1I), gingival health (GI), bleeding on probing (BoP), probing depth (PD), clinical attachment level (CAL), and microbial morphotypes from subgingival paper point samples were performed pre-irrigation, and at 1, 2, 4, 6, 8, 10, and 12 weeks post-irrigation. Mean post-irrigation P1I was low, fluctuating between 0.0 and 0.4, without significant differences between experimental groups. Mean pre-irrigation GI approximated 1.4 and reached 0.8 at the exit of study without significant differences between experimental groups. All experimental sites exhibited BoP pre-irrigation. BoP was significantly reduced in TTC50 compared to TTC10, CHX and control sites from week 8 post-irrigation. PDs were reduced for the experimental groups with TTC50 exhibiting the strongest reduction. CALs remained unaltered from pre-irrigation for TTC10, CHX and control sites over the 12-week observation interval, whereas TTC50 sites consistently improved to significantly differ from all other groups at week 10 and 12 post-irrigation. The distribution of bacterial morphotypes was significantly altered towards one of periodontal health for all experimental groups with a profound effect for TTC50 sites. Our results suggest that subgingival irrigation with TTC solutions at high concentrations may have a role in the management of adult periodontitis.

The use of metronidazole and amoxicillin in the treatment of advanced periodontal disease. A prospective, controlled clinical trial

The present clinical trial was performed to study the effect of systemic administration of metronidazole and amoxicillin as an adjunct to mechanical therapy in patients with advanced periodontal disease. 16 individuals, 10 female and 6 male, aged 35-58 years, with advanced periodontal disease were recruited. A baseline examination included assessment of clinical, radiographical, microbiological and histopathological characteristics of periodontal disease. The 16 patients were randomly distributed into 2 different samples of 8 subjects each. One sample of subjects received during the first 2 weeks of active periodontal therapy, antibiotics administered via the systemic route (metronidazole and amoxicillin). During the corresponding period, the 2nd sample of subjects received a placebo drug (placebo sample). In each of the 16 patients, 2 quadrants (1 in the maxilla and 1 in the mandible) were exposed to non-surgical subgingival scaling and root planing. The contralateral quadrants were left without subgingival instrumentation. Thus, 4 different treatment groups were formed; group 1: antibiotic therapy but no scaling, group 2: antibiotic therapy plus scaling, group 3: placebo therapy but no scaling, group 4: placebo therapy plus scaling. Re-examinations regarding the clinical parameters were performed, samples of the subgingival microbiota harvested and 1 soft tissue biopsy from 1 scaled and 1 non-scaled quadrant obtained 2 months and 12 months after the completion of active therapy. The teeth included in groups 1 and 3 were following the 12-month examination exposed to non-surgical periodontal therapy, and subsequently exited from the study. Groups 2 and 4 were also re-examined 24 months after baseline. The findings demonstrated that in patients with advanced periodontal disease, systemic administration of metronidazole plus amoxicillin resulted in (i) an improvement of the periodontal conditions, (ii) elimination/suppression of putative periodontal pathogens such as A. actinomycetemcomitans, P. gingivalis, P. intermedia and (iii) reduction of the size of the inflammatory lesion. The antibiotic regimen alone, however, was less effective than mechanical therapy with respect to reduction of BoP - positive sites, probing pocket depth reduction, probing attachment gain. The combined mechanical and systemic antibiotic therapy (group 2) was more effective than mechanical therapy alone in terms of improvement of clinical and microbiological features of periodontal disease.

Differential clinical treatment outcome after systemic metronidazole and amoxicillin in patients harboring Actinobacillus actinomycetemcomitans and/or Porphyromonas gingivalis

48 adult patients with untreated periodontitis harboring subgingival Actinobacillus actinomycetemcomitans and/or Porphyromonas gingivalis as assessed by PCR were randomly assigned to receive full-mouth scaling alone (control) or scaling with systemic metronidazole plus amoxicillin and supragingival irrigation with chlorhexidine digluconate (test). In patients harboring A. actinomycetemcomitans intraorally at baseline, the adjunctive antimicrobial therapy resulted in a significantly higher incidence of probing attachment level (PAL) gain of 2 mm or more compared to scaling alone over 12 months (p<0.05). In addition, suppression of A. actinomycetemcomitans in subgingival plaque below detectable levels was associated with an increased incidence of PAL gain. In contrast, patients initially harboring P. gingivalis but not A. actinomycetemcomitans in the oral cavity showed a significantly higher incidence of PAL loss following adjunctive antimicrobial therapy compared to scaling alone (p<0.05). When the presence of pathogens at baseline was disregarded in the analysis, adjunctive antimicrobial therapy did not significantly enhance clinical treatment outcome. The results indicated that adults with untreated periodontitis harboring A. actinomycetemcomitans may benefit from the adjunctive antimicrobial therapy for a minimum of 12 months, whereas, the regimen may adversely affect the clinical treatment outcome of patients harboring P. gingivalis but not A. actinomycetemcomitans.

Differential effects of systemic metronidazole and amoxicillin on Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in intraoral habitats

48 adult patients with untreated periodontitis harboring subgingival Actinobacillus actinomycetemcomitans and/or Porphyromonas gingivalis were randomly assigned to receive full mouth scaling alone (control) or scaling with systemic metronidazole plus amoxicillin and supragingivai irrigation with chlorhexidine digluconate (test). Subgingival plaque and swab samples from tongue, tonsils, and buccal mucosa were taken at baseline, 10 days and 3, 6, 9, and 12 months. A. actinomycetemcomitans was detected in the oral cavity, i.e., subgingival plaque and/or mucous membranes, less frequently in test patients compared to controls at 9 and 12 months (p<0.01), whereas, the intraoral detection frequency of P. gingivalis was significantly reduced only 10 days following therapy (p<0.001). At any time after therapy, A. actinomycetemcomitans was not detected intraorally in 5 of 10 (50%) test and 1 of 13 (8%) control patients harboring this pathogen at baseline; P. gingivalis was not detected in only 1 of 18 (6%) test and none of the 17 control patients harboring this pathogen at baseline. Although the data indicated that the assessed antimicrobial therapy may suppress A. actinomycetemcomitans from the entire oral cavity below detectable levels over a minimum of 12 months, P. gingivalis persisted or reoccurred.

Bacterial reduction in periodontal pockets through irradiation with a diode laser: a pilot study

This study examines the application of a diode laser with a wavelength of 805 nm for periodontal treatment. While the use of the diode laser in this field has not been investigated so far, several authors have reported on the use of neodymium:yttrium-aluminum-garnet (Nd:YAG) laser for such applications. The aim of this study was to examine the immediate effect of the diode laser in reducing the bacterial concentration in periodontal pockets. Important periodontal indices (PBI, CPITN) were assessed in 50 patients to obtain initial values for a planned long-term study and to select appropriate periodontal pockets for this study. The periodontal pockets were required to have a minimum depth of 4 mm. Only proximal pockets were included in this study. The patients were subdivided into two groups. After microbiological samples had been collected with sterile paper tips, the group selected for laser treatment was subjected to scaling. One week after scaling, the patients underwent laser treatment. One week later, a second series of microbiological samples were obtained and the patients were subjected again to scaling; this time, however, they did not undergo laser treatment after 1 week. Two weeks after scaling, another series of microbiological samples was collected. The microbiological samples were evaluated to verify bacterial elimination from the periodontal pockets. A comparison between the initial and the final bacterial counts revealed that irradiation with the diode laser facilitates considerable bacterial elimination, especially of Actinobacillus actinomycetemcomitans, from periodontal pockets.

Colonization by Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia in adult periodontitis patients as detected by the antibody-based Evalusite Test

Studies were performed to evaluate the detection of disease-associated bacterial colonization in adult periodontitis patients by the antibody-based Evalusite TestTM (Eastman Kodak Company). The association of test results with disease was assessed by collecting 104 duplicate subgingival plaque samples from 26 patients. Samples were tested for Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia using both microbiological culture and the immunoassay test. The sensitivity and specificity of the 2 methods was calculated using %s of positive results in deep periodontal pockets and negative results in shallow subgingival sites. A cutoff >10(4) cultivable counts yielded the greatest discrimination between health and disease on a cross-sectional basis and established this threshold as clinically relevant for the detection of disease-associated levels of bacterial colonization by these three microorganisms. The clinical detection limit of the immunoassay test was observed to coincide with this threshold of >10(4) cultivable counts. Microbiological testing of the 4 deepest pockets using the immunoassay test was determined to be sufficient to yield a 90% confidence of detecting positive patients in a study with 59 adult subjects. The immunoassay test method was also demonstrated to be effective at detecting bacterial colonization in sets of paper point samples that were pooled for analysis. An overall agreement of 94% (288 of 306) was observed when comparing test results for duplicate sets of pooled and individual samples collected from 51 patients. These studies demonstrate that the Evalusite Test is an effective method for detecting clinically relevant colonization by the test bacteria in patients at risk for periodontal disease.

Analytical performance of an immunologic-based periodontal bacterial test for simultaneous detection and differentiation of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia

The analytical performance of a membrane-based immunoassay for the simultaneous detection and differentiation of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia (including Prevotella nigrescens) was investigated. Positive reactions were observed for 71 of 71 reference strains and recent oral isolates of A. actinomycetemcomitans, P. gingivalis, and P. intermedia. No cross-reactivity was observed with 39 other common oral and environmental species. The specificity of the test was unaffected by the presence of potential oral interferents including whole blood, white blood cells, mucin, saliva, toothpastes, and oral rinses. A proficiency test by dental professionals using a standardized set of unknown simulated samples yielded a sensitivity of 97% (116/120) and a 100% specificity (240/ 240). An additional group including dental professionals and high school students was shown to be 99% proficient (1385/1397) in distinguishing proper from improper test function when processing control samples with normal test devices and devices with simulated error conditions. Comparisons to a culture standard for 104 subgingival plaque samples collected from 26 adult periodontitis patients yielded > 98% specificity for each of the test bacteria. In addition, the detection threshold for the test was determined to be equivalent to 10(4) cultivable test bacteria when compared to the culture standard. The data indicate that this membrane immunoassay is a valid and easy-to-use method for the detection of A. actinomycetemcomitans, P. gingivalis, and P. intermedia in subgingival plaque, at levels above the detection threshold of the test.

Microbiological monitoring

If periodontal disease is due to a limited number of bacterial species, then continuous maximal plaque suppression is not the only possibility for prevention and therapy. Specific elimination or reduction of pathogenic bacteria from plaque becomes a valid alternative. Recent studies indicate that the elimination of certain putative pathogens is particularly difficult. New diagnostic methods should allow the choice of better suited procedures, make chosen procedures more effective (through better timing, dosage, selection of devices or drugs, increase of specificity, etc.) or lead to the elimination of unnecessary work (e.g., the treatment of non-susceptible sites or patients). The benefit of newly proposed tests depends on the possible impact of the obtained information on clinical decisions and on the consequences these decisions have for treatment. Thus, diagnostic methods and therapeutical options have to be evaluated together.

Clinical and microbiological changes associated with the use of 4 adjunctive systemically administered agents in the treatment of periodontal infections

The purpose of the present investigation was to assess the effects of periodontal surgery and 4 systemically administered agents, Augmentin, tetracycline, ibuprofen or a placebo on clinical and microbiological parameters of periodontal disease. 98 subjects were monitored at 2-month intervals at 6 sites per tooth for clinical parameters. Subgingival plaque samples were taken from the mesial surface of each tooth at each visit and evaluated for their content of 14 subgingival species using DNA probes and a colony lift method. 40 subjects who exhibited loss of attachment > 2.5 mm at 1 or more sites during longitudinal monitoring were treated using modified Widman flap surgery at sites with probing pocket depth > 4 mm, subgingival scaling at all other sites and were randomly assigned 1 of the 4 agents. Treatment was completed within 30 days during which time the subject took the assigned agent. Overall, subjects exhibited a mean attachment level "gain" of 0.34 +/- 0.10 mm (SEM) and a mean pocket depth reduction of 0.62 +/- 0.09 mm 10 +/- 4 months post-therapy. However, certain subjects in each treatment group showed a poor response. Subjects receiving antibiotics exhibited significantly more attachment level "gain" (0.57 +/- 0.15 mm, SEM) than subjects receiving either ibuprofen or a placebo (0.02 +/- 0.10). The differences between Augmentin and tetracycline groups were not significant, nor were the differences between ibuprofen and placebo. 10 months post-therapy, there was a reduction in the number of sites colonized in any subject group by detectable levels (10(3)) of P. gingivalis. Species showing similar reductions were B. forsythus, P. intermedia and P. micros. Subjects receiving systemically administered antibiotics had a significant increase in the proportion of sites colonized by C. ochracea coupled with a greater decrease in the number of sites colonized by P. gingivalis, B. forsythus, P. intermedia and P. micros post-therapy than subjects not receiving antibiotics. The results of this investigation indicate that adjunctive systemic antibiotics increase periodontal attachment "gain" and decrease the levels of some suspected periodontal pathogens in subjects with evidence of current disease progression.

Prognostic criteria for the efficiency of non-surgical periodontal therapy in advanced periodontitis

The aim of the study was to find out which clinical, radiographic and microbiological variables can be used as prognostic criteria for the efficiency of the commonly used initial treatment protocol comprising scaling, root planning and instruction on oral hygiene in advanced adult periodontitis. 46 patients (mean age 48 years) with untreated, advanced periodontitis volunteered for the study. The clinical examination included recordings of plaque, gingival and calculus indices, probing pocket depths, bleeding and suppuration after probing, probing attachment levels and furcation involvements. Infrabony and furcation lesions were assessed from panoramic radiographs. Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were cultured from the deepest, most inflamed periodontal Pockets, from surface of the tongue and from saliva. 3 months after the completion of non-surgical treatment comprising meticulous scaling and root planing and instruction on oral hygiene, the healing was assessed clinically, and 13 patients were assigned to a maintenance care programme (MC) and 33 to further treatment procedures (FT). Evaluation of the baseline clinical and radiographic data showed a significantly higher %s of > or = 6 mm deep periodontal pockets, surfaces with suppuration, and sites with subgingival calculus, as well as higher numbers of infrabony lesions, in FT-patients than in MC-patients. Subgingival A. actinomycetemcomitans was isolated at baseline in 55% of the FT-patients and in 38% of the MC-patients, and P. gingivalis in 27% and 23%, respectively. A. actinomycetemcomitans was eradicated by non-surgical treatment from only one patient. P. gingivalis was detected in 15% of the patients in both groups after treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Physiopathology of primary periodontitis associated with plaque. Microbial and host factors. A review. Part 2

To a considerable extent, host factors condition the initiation and progression of periodontitis. The integrity of the periodontal structures and the immune elements in the gingival fluid may act as a defensive barrier against microorganisms. However, immune over-response may lead to tissue damage and bone resorption from anaphylactic reactions, immunocomplex reactions, type IV hypersensitivity, complement hyperactivation via the alternative pathway, or direct action of leukocytes and macrophages. Moreover, insufficient host response allows bacteria to escape control, allowing more rapid progression of the disease.

Microbiological and clinical effects of metronidazole and amoxicillin in Actinobacillus actinomycetemcomitans-associated periodontitis. A 2-year evaluation

In this study, we evaluated the microbiological and clinical effects of mechanical debridement in combination with metronidazole and amoxicillin therapy in 48 patients with Actinobacillus actinomycetemcomitans-associated periodontitis, 3 months and at least 24 months after active treatment. The results of this study showed that 47 out of 48 patients were still negative for A. actinomycetemcomitans subgingivally, at the mucous membranes, the tonsillar area and in the saliva, 2 years after therapy. The clinical results showed that a reduction of probing pocket depth, probing attachment level, bleeding index and plaque index was not only seen in the time between baseline and 3 months after therapy, but further clinical improvement was observed between 3 and 24 months after active treatment. We conclude that combined mechanical debridement and metronidazole plus amoxicillin therapy is very effective in suppressing A. actinomycetemcomitans below cultivable levels over a long period of time, suggesting elimination of this organism, and that recolonization of A. actinomycetemcomitans seems to be a rare event. The elimination of A. actinomycetemcomitans is paralleled by a further improvement of the periodontal status of the patients, even up to 24 months after active treatment.

Impact of microbiological consultation on clinical decision making: a case-control study of clinical management of recurrent periodontitis

Data obtained from diagnostic tests may influence the clinician's perception of the patient's state and in some instances may alter subsequent choices of therapeutic interventions. To determine if microbiological consultation influences the clinical management of patients with recurrent periodontitis, an observational, case-control study was conducted to measure the amount and type of periodontal treatment provided by periodontists (n = 13) who had referred patients with recurrent periodontitis for microbiological consultation. The control group consisted of periodontists (n = 10) who had not referred recurrent periodontitis patients for testing. Patients (n = 31; 20 females, 11 males; mean age 49.8 +/- 10.0 years) treated by the case group of periodontists were matched for age and sex to patients (n = 48; 22 females, 26 males; mean age 49.9 +/- 8.5 years) treated by the control group of periodontists. Questionnaires were administered to quantitatively assess the amount and type of treatment before and after receiving the microbiological report. Specific analyses were performed as a function of the time of receipt of the microbiology report. Case-control differences prior to the receipt of the report indicated that the amount of surgery/year was 43% greater for controls (P < 0.04), in spite of control patients exhibiting fewer deep pockets than case patients (P < 0.05). Case-control differences after the receipt of the report indicated that case patients were provided with 45% greater number of appointments/year (P < 0.005), 46% greater scaling/year (P < 0.02), and 79% greater antibiotics/year (P < 0.01) compared with controls. The report influenced 9 (69%) case periodontists to change treatment. Case patients who received a change in treatment (n = 21) exhibited greater number of deep pockets at the time of entry into the study (P < 0.05) as compared with case patients who did not receive a change in treatment. Paired t-tests of differences within groups before and after the report demonstrated that case patients had a significant increase in treatment after the report as shown by 22% greater number of visits/year (P < 0.05) and 54% greater number of antibiotic prescriptions/year (P < 0.01). In contrast, controls demonstrated no significant change in treatment. Further, contrasts of change in treatment before and after the report again indicated that case patients exhibited a significantly higher number of visits/year (P < 0.04) and number of antibiotic prescriptions/year (P < 0.02) compared with control patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Role of suspected periodontopathogens in microbiological monitoring of periodontitis

Periodontal disease is the clinical result of a complex interaction between the host and plaque bacteria. Although a specificity to some degree is found for Actinobacillus actinomycetemcomitans in localized juvenile periodontitis (LJP), it has been difficult to obtain evidence for a specific etiological role of the bacteria associated with periodontal disease in adults. What we see is the net result of host-parasite interactions which in an unpredictable moment accumulate and exceed the threshold of tissue integrity. This hypothesis is concomitant with the view of periodontal disease as a polymicrobial infection, predominantly anaerobic, which occurs commonly in the oral cavity or elsewhere in the body. Some micro-organisms (risk markers) occur more frequently than others and may significantly determine the outcome of this host-parasite interaction. Microbiological sampling and analysis seem to be of limited value in risk assessment; however, they can be used as tools in diagnosis in LJP patients and acute infections, and in treatment decision and therapy control in "refractory" patients. Suspected pathogens (risk markers) are Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and some species of spirochetes, while the roles of Prevotella intermedia, Bacteroidesforsythus, Fusobacterium nucleatum, Campylobacter rectus, and Peptostreptococcus micros are more uncertain. The presence of periodontopathogens as well as enterics, Staphylococcus aureus and Candida especially, should be considered in patients with systemic individual disorders--e.g., diabetes mellitus, neutropenia, agranulocytosis, and AIDS--or with implants.

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.

Significance of serum antibody against surface antigens of Actinobacillus actinomycetemcomitans in patients with adult periodontitis

This study was undertaken to examine the prevalence of Actinobacillus actinomycetemcomitans, its serotype distribution and the serum immune responses against its surface antigens in 41 Japanese patients with adult periodontitis. The dominant A. actinomycetemcomitans serotype isolated was serotype c. Immunoblot analysis of 3 serotypes of A. actinomycetemcomitans-sonicated antigens and the patient sera revealed that the reactivities with serotype c were the most frequent and that heat-stable surface serotype-specific antigen appeared to be immunodominant. Elevated serum immunoglobulin G titers to extracted lipopolysaccharide and fimbriae antigen of A. actinomycetemcomitans were noted for the patient sera by enzyme-linked immunosorbent assay. High serum immunoglobulin G titers to the fimbriae antigen detected in patients without cultivable A. actinomycetemcomitans suggested the possibility that the elicited antibody to the antigen played a role in eliminating A. actinomycetemcomitans from the periodontal lesions.

Evaluation of the E test for antimicrobial susceptibility testing of Actinobacillus actinomycetemcomitans

The E test was compared with an agar dilution method for antimicrobial susceptibility testing of Actinobacillus actinomycetemcomitans on Mueller-Hinton Haemophilus test medium. Eighty recent isolates of A. actinomycetemcomitans from 40 subjects and 3 reference strains were studied. Excellent agreement was obtained between the E test and the agar dilution test for benzylpenicillin (98.8%), ampicillin (97.5%), cefaclor (100%), cefuroxime (100%), tetracycline hydrochloride (100%) and ciprofloxacin (98.7%); 76.0% agreement was obtained for metronidazole and only 5.2% for cotrimoxazole. This study indicates that the E test is a reliable method to determine minimal inhibitory concentrations of antimicrobials against A. actinomycetemcomitans, except for metronidazole and cotrimoxazole.