A randomized, placebo-controlled trial of doxycycline: effect on the microflora of recurrent periodontitis lesions in high risk patients

Europe's contribution to the evaluation of the use of systemic antimicrobials in the treatment of periodontitis

This narrative review celebrates Europe's contribution to the current knowledge on systemically administered antimicrobials in periodontal treatment. Periodontitis is the most frequent chronic noncommunicable human disease. It is caused by dysbiotic bacterial biofilms and is commonly treated with subgingival instrumentation. However, some sites/patients do not respond adequately, and its limitations and shortcomings have been recognized. This has led to the development of alternative or adjunctive therapies. One is the use of antimicrobials to target bacteria in subgingival biofilms in the periodontal pocket, which can be targeted directly through the pocket entrance with a locally delivered antibiotic or systemically by oral, intravenous, or intramuscular methods. Since the early 20th century, several studies on systemic antibiotics have been undertaken and published, especially between 1990 and 2010. Europe's latest contribution to this topic is the first European Federation of Periodontology, S3-level Clinical Practice Guideline, which incorporates recommendations related to the use of adjuncts to treat stage I-III periodontitis. Understanding the etiopathogenesis of periodontal diseases, specifically periodontitis, has influenced the use of systemic periodontal antibiotic therapy. Randomized clinical trials and systematic reviews with meta-analyses have demonstrated the clinical advantages of adjunctive systemic antimicrobials. However, current recommendations are restrictive due to concerns about antibiotic misuse and the increase in microbial antibiotic resistance. European researchers have contributed to the use of systemic antimicrobials in the treatment of periodontitis through clinical trials and by providing rational guidelines. Nowadays, European researchers are exploring alternatives and directing clinical practice by providing evidence-based guidelines to limit the use of systemic antimicrobials.

Efficacy of doxycycline release collagen membrane on surgically created and contaminated defects in rat tibiae: A histopathological and microbiological study

BACKGROUND

The effects of systemic antibiotics on controlling infective pathogens after guided bone regeneration(GBR) procedures especially in membrane exposures are limited. However, local administrations of antibiotics are rare in GBR techniques.

AIM

The aim of this study was to investigate the osteogenesis potential and the antibacterial effect of a doxycycline releasing collagen membrane in surgically created and contaminated defects in rat tibiae.

MATERIAL AND METHODS

Defects were created in 20 rats that were randomly divided in to two groups: control group (defect contaminated by Porphyromonas gingivalis, filled with bone graft and covered by collagen membrane); test group (defect contaminated by P. gingivalis filled with bone graft and covered by collagen membrane containing 1mg/cm(2) doxycycline. Animals were sacrificed post surgically on the 14th day for microbiologic evaluation and on the 28th day for histopathological evaluation.

RESULTS

The degree of osteogenesis in the test group was seen to be significantly higher than control group (p: 0.011; p<0.05). Furthermore in test group, no bacterial growth was observed. The bacteria counts were determined between 1×104 and 268×104CFU/g with a median of 1.32×104 for control group.

CONCLUSIONS

Within the limitations of this study, the results of the present study suggests that the use of a doxycycline releasing membrane has a positive effect on contaminated GBR procedures for limiting P. gingivalis infections leading to bone formation following GBR procedures in a rat model.

Effects of doxycycline on clinical, microbiological and immunological parameters in well-controlled diabetes type-2 patients with periodontal disease: a randomized, controlled clinical trial

AIM

To evaluate the clinical, microbiological and immunological effects of systemic doxycycline as an adjunct to scaling and root planing (SRP) in chronic periodontitis patients with well-controlled type 2 diabetes.

MATERIALS AND METHODS

Sixty-six patients compliant to oral hygiene (Hygiene Index <20%) allocated to either a test (systemic doxycycline for 21 days) or a control (placebo) group participated in the present randomized controlled trial (RCT). Clinical assessments were recorded at baseline, 3 and 6 months after therapy and included clinical attachment level (CAL), set as the primary outcome of the study, probing pocket depth (PPD), recession (RE) and bleeding on probing (BOP). At the same time points, counts of 15 subgingival species were evaluated by "checkerboard" DNA-DNA hybridization, gingival crevicular fluid samples were analysed for matrix metalloproteinase-8 (MMP-8) by ELISA and HbA1c levels were determined. Comparisons between and within groups were performed by non-parametric tests (Mann-Whitney, Wilcoxon signed-ranks and z-test for proportions with Bonferroni corrections) at the 0.05 level.

RESULTS

No major differences were noticed in clinical and microbiological parameters of periodontal disease or levels of MMP-8 between the two groups.

CONCLUSIONS

Adjunctive systemic doxycycline does not seem to significantly enhance the effects of SRP in well-controlled diabetes type 2 patients.

The use of controlled release locally delivered 10% doxycycline hyclate gel as an adjunct to scaling and root planing in the treatment of chronic periodontitis: clinical and microbiological results

BACKGROUND

Local delivery of antimicrobial agents provides higher concentration of the drug in the periodontal site for longer periods than systemically delivered methods. In the present study an attempt is made to know the efficacy of controlled local drug delivery of doxycycline as an adjunctive treatment in the management of chronic periodontitis.

MATERIALS AND METHODS

A total of 12 patients, diagnosed as Chronic Periodontitis in the age of 25 to 55 years, were selected of both the sexes in this study. They were divided into Experimental group consisted of 30 sites who received complete scaling and root planing (SRP) followed by placement of Atridox gel and control group consisted of 30 sites who received only SRP. Clinical parameters were recorded at, baseline, days 30, 90 and 180. Parameters were plaque index, gingival index, gingival bleeding index and microbial analysis, probing pocket depth and Clinical attachment level (CAL). The microbiological analysis was done at baseline visit and at 90th day. Probing pocket depth and CAL were recorded only on day 0 and 180th day.

RESULTS

In 180 days study, both the groups exhibited a significant improvement in periodontal status. Significant gain in attachment level was observed in both the group. Between both the groups the clinical parameters in the experimental groups exhibited better results as compared to the control group. Both the groups exhibited significant reduction in the number of spirochetes.

CONCLUSION

Combination therapy of SRP and 10% DH gel demonstrated better results at all levels suggesting that this therapy can play a significant role as an adjunct to SRP in the management of chronic periodontitis.

Efficacy of locally-delivered doxycycline microspheres in chronic localized periodontitis and on Porphyromonas gingivalis

AIM

This study aimed to assess the efficacy and effect of locally-delivered doxycycline microspheres with scaling and root planing in periodontal pocket therapy and on Porphyromonas gingivalis, respectively.

METHODS

Twenty sites with a probing pocket depth of 4-6 mm were divided into two groups: a control group consisting of scaling and root planing, with one application of doxycycline microspheres only at baseline, and a test group consisting of scaling and root planing, with an application of doxycycline microspheres at baseline and 1 and 3 months. Clinical readings included the plaque index, gingival index, probing pocket depth, and relative attachment level. Rapid polymerase chain reaction method was used for the detection of P. gingivalis.

RESULTS

A statistically-significant reduction in probing pocket depth and attachment gain was found in both groups; the test group showed a significant reduction in probing pocket depth and attachment gain compared with the control at 3 and 6 months. P. gingivalis cell count in the test group was significantly reduced at all the time periods, except from 1 to 3 months.

CONCLUSION

Local drug delivery of doxycycline microspheres significantly improved the treatment outcomes in periodontal pocket therapy and reduced P. gingivalis in the periodontal pocket.

Long-term efficacy of subantimicrobial-dose doxycycline as an adjunctive treatment to scaling and root planing: a systematic review and meta-analysis

BACKGROUND

Subantimicrobial-dose doxycycline (SDD) is widely used as an adjunctive treatment to scaling and root planing (SRP), but its long-term effectiveness remains controversial. The purpose of this systematic review was to assess the actual evidence of the effectiveness of SRP + SDD compared to SRP + placebo in the treatment of chronic periodontitis.

METHODS

A literature search of electronic databases was performed for articles published through November 1, 2010. Several dental journals were screened during the manual search, and authors were contacted for missing information. The systematic review and meta-analysis were conducted according to the Quality of Reporting of Meta-Analyses statement and recommendations of the Cochrane Collaboration. The methodologic quality of the studies was determined via a Consolidated Standards of Reporting Trials-based assessment. Clinical attachment levels, probing depths, plaque and gingival indices, and gingival crevicular fluid levels were compared between baseline and the end of follow-up. Data were extracted and pooled using a random-effect model. The weighted mean difference was reported with the 95% confidence interval. Heterogeneity was assessed using the χ(2)-based Q-statistic method and I(2) measurement. P <0.05 was considered statistically significant.

RESULTS

After applying inclusion and exclusion criteria, three randomized placebo-controlled clinical trials were entered into the meta-analysis. These studies had similar treatment designs, SDD dosage regimens (20 mg twice daily for 3 months), and post-treatment follow-up lengths (9 months). Significant differences were observed for all investigated clinical parameters in favor of the SRP + SDD group.

CONCLUSION

The meta-analysis results seemed to support the long-term effectiveness of adjunctive SDD therapy; however, future studies are needed to confirm these findings.

Antimicrobial therapy in periodontitis: the use of systemic antimicrobials against the subgingival biofilm

OBJECTIVES

The aim was to answer three relevant questions: can systemic antimicrobials be efficacious if the biofilm is not disrupted? Can the type of debridement of the subgingival biofilm impact upon the clinical outcomes of the adjunctive antimicrobial therapy? Is the efficacy of the adjunctive systemic antimicrobial therapy dependent on the quality of the debridement of the subgingival biofilm and the sequence debridement-antibiotic usage?

MATERIAL AND METHODS

Relevant papers were searched, critically analysed and their data were extracted.

RESULTS

For the first question, studies assessing susceptibility of bacteria in biofilms, and clinical studies evaluating systemic antimicrobials as monotherapy, were reviewed. For the second question, clinical studies comparing systemic antimicrobials as adjuncts to non-surgical debridement or to periodontal surgery and clinical trials using systemic antibiotics with periodontal surgery were evaluated. For the third question, a previous systematic review was updated.

CONCLUSION

If systemic antimicrobials are indicated in periodontal therapy, they should be adjunctive to mechanical debridement. There is not enough evidence to support their use with periodontal surgery. Indirect evidence suggests that antibiotic intake should start on the day of debridement completion, debridement should be completed within a short time (preferably <1 week) and with an adequate quality, to optimize the results.

Clindamycin in dentistry: More than just effective prophylaxis for endocarditis?

Clindamycin is a broad-spectrum antibiotic with activity against aerobic, anaerobic, and beta-lactamase-producing pathogens. This antibiotic has been used for many years as prophylactic treatment during dental procedures to prevent endocarditis. However, the spectrum and susceptibility of the bacteria species involved in dental infections indicate that clindamycin would also be an effective treatment option for these conditions. In addition to its antiinfective properties, clindamycin has high oral absorption, significant tissue penetration, including penetration into bone, and stimulatory effects on the host immune system. This review discusses the microbiologic and clinical evidence supporting the efficacy and safety of clindamycin for the successful management of dental infections.

Systemic anti-infective periodontal therapy. A systematic review

BACKGROUND

Periodontal diseases are infections and thus systemically administered antibiotics are often employed as adjuncts for their control. There are conflicting reports as to whether these agents provide a therapeutic benefit.

RATIONALE

The purpose of this systematic review is to determine whether systemically administered antibiotics improve a primary clinical outcome measure, periodontal attachment level change.

FOCUSED QUESTION

In patients with periodontitis, what is the effect of systemically administered antibiotics as compared to controls on clinical measures of attachment level?

SEARCH PROTOCOL

The Pub/Med database was searched from 1966 to May 2002. Searches were limited to human studies published in English. Hand searches were performed on the Journal of Clinical Periodontology, Journal of Periodontology, and Journal of Periodontal Research. References in relevant papers and review articles were also examined.

SELECTION CRITERIA

INCLUSION CRITERIA

Trials were selected if they met the following criteria: randomized controlled clinical trials, quasi-experimental studies, and cohort studies of > 1 month duration with a comparison group; subjects with aggressive, chronic, or recurrent periodontitis and periodontal abscess; use of a single or a combination of systemically administered antibiotics(s) versus non-antibiotic therapy; and a primary outcome of mean attachment level change (AL).

EXCLUSION CRITERIA

Studies involving the use of low-dose doxycycline, combinations of locally plus systemic antibiotics, or where the control group included a systemically administered antibiotic were excluded.

DATA COLLECTION AND ANALYSIS

A mean difference in AL between groups was available for all papers used in the meta-analysis. A standard deviation (SD) for the difference was used if provided or calculated from the SD or standard error of the mean (SEM) when provided for single measurements. Data were subset by antibiotic employed, type of adjunctive therapy, and disease type. Results were assessed with both fixed-effects and random-effects models.

MAIN RESULTS

1. Twenty-nine studies, 26 RCTs and 3 quasi-experimental (36 comparisons), met the entry criteria. Total study population, both control and test groups, was estimated at over 1,200. 2. Twenty-two studies (27 comparisons) were used in the meta-analysis, evaluating if the antibiotics provided a consistent benefit in mean AL change for different patient populations, for different therapies, and for different antibiotics. 3. For the majority of the comparisons, systemically administered antibiotics exhibited a more positive attachment level change than the control group in the study. The combined results were statistically significant (P < 0.001). 4. The systemic antibiotics were uniformly beneficial in providing an improvement in AL when used as adjuncts to scaling and root planing (SRP) and were consistently beneficial, although of borderline significance, when used as adjuncts to SRP plus surgery or as a stand alone therapy. 5. When examining the effects of individual or combinations of antibiotics, it was found that there were statistically significant improvements in AL for tetracycline, metronidazole, and an effect of borderline statistical significance for the combination of amoxicillin plus metronidazole. 6. Improvements in mean AL were consistent for both chronic and aggressive periodontitis subjects, although the aggressive periodontitis patients benefited more from the antibiotics.

REVIEWERS' CONCLUSIONS

1. The use of systemically administered adjunctive antibiotics with and without SRP and/or surgery appeared to provide a greater clinical improvement in AL than therapies not employing these agents. 2. The data supported similar effect sizes for the majority of the antibiotics; therefore, the selection for an individual patient has to be made based on other factors. 3. Due to a lack of sufficient sample size for many of the antibiotics tested, it is difficult to provide guidance as to the more effective ones.

A systematic review on the effect of systemic antimicrobials as an adjunct to scaling and root planing in periodontitis patients

BACKGROUND

Scaling and root planing (SRP) are the bases of non-surgical therapy in the treatment of periodontitis. However, results from this therapy are often unpredictable and dependable from many different factors.

OBJECTIVES

The aim of this systematic review was to evaluate the effectiveness of the adjunctive use of systemic antimicrobials with scaling and root planing (SRP) vs. SRP alone in the treatment of chronic (CP) or aggressive periodontitis (AgP).

SEARCH STRATEGY

Use of computerized databases, namely MEDLINE, the Cochrane Oral Health Group Specialty Trials Register and EMBASE; reference lists from relevant articles were hand-searched; and a hand-search of selected journals until April 2001.

SELECTION CRITERIA

Studies were selected if they were designed as controlled clinical trials in which systemically healthy patients with either AgP or CP were treated with SRP plus systemic antimicrobials in comparison with SRP alone or with placebo, for a minimum of 6 months. Main outcome measures were clinical attachment level (CAL) change and probing pocket depth (PPD) change.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted independently information regarding quality and study characteristics, in duplicate. Kappa scores determined their agreement. Main results were collected and grouped by drug, disease and PPD category. For the quantitative data synthesis, the data was pooled (when mean differences and standard errors were available), and either a Fixed Effects or Random Effects meta-analysis was used for the analysis.

RESULTS

After an initial selection, 158 papers were identified by the manual and electronic searches; 25 papers were eligible for inclusion. Their quality assessment showed that randomization and allocation concealment methods were seldom reported and blindness was usually not defined clearly. In general, selected studies showed high variability and lack of relevant information for an adequate assessment. Overall, SRP plus systemic antimicrobial groups demonstrated better results in CAL and PPD change than SRP alone or with placebo groups. Only limited meta-analyses could be performed, due to the difficulties in pooling the studies and the lack of appropriate data. This analysis showed a statistically significant additional benefit for spiramycin (PPD change) and amoxicillin/metronidazole (CAL change) in deep pockets.

CONCLUSION

Systemic antimicrobials in conjunction with SRP, can offer an additional benefit over SRP alone in the treatment of periodontitis, in terms of CAL and PPD change, and reduced risk of additional CAL loss. However, differences in study methodology and lack of data precluded an adequate and complete pooling of data for a more comprehensive analyses. It was difficult to establish definitive conclusions, although patients with deep pockets, progressive or 'active' disease, or specific microbiological profile, can benefit more from this adjunctive therapy.

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.

Periodontal abscess

This review focuses on the classification of periodontal abscesses, which are localized purulent infections of periodontal tissues, and discusses their etiology and clinical characteristics.

Effects of metronidazole plus amoxicillin in progressive untreated adult periodontitis: results of a single 1-week course after 2 and 4 months

A randomized, double-blind, clinical study was done to assess the microbiological and clinical effects of metronidazole plus amoxicillin (M+A) as the only therapy in 46 patients with moderate to advanced progressive adult periodontitis. Patients were included in the study after at least 2 sites showed > or =2 mm clinical attachment loss. Bleeding on probing, probing depth, and clinical attachment level were measured using on automated probe. The percentage of surfaces with plaque was recorded at day 0, and at 2 and 4 months after therapy. No effort was made to change the oral hygiene habits of patients. Identification of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia was assessed utilizing DNA technology at day 0 and 2 months after therapy. Twenty-three patients received metronidazole 250 mg plus amoxicillin 500 mg, 3 times/day for a week and 23 a placebo. Two patients in the placebo group were dropped at 2 months because they had taken antibiotics for medical reasons. Statistical analyses of differences between groups was done using the Mann-Whitney test, and the differences within each group were tested with ANOVA. There were no significant changes in surfaces with plaque in either group after therapy. The percentage of bleeding sites decreased significantly from baseline to 2 and 4 months in the M+A group (P = 0.001), and increased in the placebo group. Differences in bleeding on probing between groups were significant at 2 (P = 0.018), and 4 months (P = 0.005). The mean attachment level values at 2 and 4 months post-therapy improved significantly in the M+A group compared to the placebo group (P = 0.001). Treatment with M+A resulted in a significant mean reduction in probing depth at 2 and 4 months compared to baseline values (P = 0.001). The M+A group showed a significant reduction of sites with high levels of Pg (P = 0.001) at 2 months compared with baseline values, and there was a significant reduction of sites with Pg and Pi in the M+A group compared with the placebo group. The results showed that a combined M+A treatment as the only therapy changes the proportion of some subgingival microorganisms and allows a significant improvement in clinical conditions.

The use of locally delivered doxycycline in the treatment of periodontitis. Clinical results

The clinical safety and effectiveness of a subgingivally delivered biodegradable drug delivery system containing doxycycline hyclate (DH) has been evaluated in 3 large 9-month multicenter randomized parallel-design controlled clinical trials. A total of 1002 patients having at least 2 quadrants with a minimum of 4 qualifying pockets > or = 5 mm that bled on probing were enrolled. Each subject had > or = 7 mm probing depths in 2 of the qualifying pockets. Study 1 (n=180) compared DH to sanguinarine chloride (SC) and vehicle control (VC). Study 2 (n=411) and study 3 (n=411) compared DH to VC, scaling and root planing (SRP), and oral hygiene (OH). Clinical measurements included probing depth reduction (PDR), attachment level gain (ALG), bleeding on probing reduction (BOP) and plaque index (PI). Analysis of efficacy data from these 3 trials show all treatments gave significant positive clinical changes from baseline at most time points. Study 1 results indicate that DH was superior to SC and VC in PDR at all time points. Similar results were obtained for ALG when DH was compared to SC and VC. For BOP reductions, DH was superior to VC at all time points and to SC at months 5 through 9. For DH, mean ALG in deep (> or = 7 mm) pockets was 1.4 mm; mean PDR for DH was 2.6 mm. For moderate (5 to 6 mm) pockets, ALG was 0.8 mm and PDR 1.5 mm. Studies 2 and 3 reported mean month 9 ALG for SRP as 0.7 mm and 0.8 mm, respectively. For DH, ALG was 0.8 mm in both studies 2 and 3. At month 9 in studies 2 and 3, 29% and 31% of DH sites and 27% and 34% of SRP sites showed ALG > or = 2 mm. Probing depth reductions followed the same pattern, with 32% of DH sites and 32% of SRP sites showing > or = 2 mm PD reductions in study 2, and 41% of DH and 43% of SRP sites showing PDR of > or = 2 mm in study 3. Comparisons between DH, VC, and OH treatment groups in studies 2 and 3 showed DH treatment was statistically superior to VC and OH at most time points. Results of these 3 large clinical trials demonstrate that treatment of periodontitis with 10% doxycyline hyclate in a bioabsorbable delivery system is equally as effective as SRP and superior in effect to VC and OH in reducing the clinical signs of adult periodontitis.

Tetracycline and its analogues: a therapeutic paradigm in periodontal diseases

This article discusses the use of tetracyclines in the clinical management of periodontal infections. A review of the drugs pharmacology, pharmacokinetics, and potential adverse effects shows that they are relatively safe if used in appropriate dosages and under controlled conditions. Current data suggest that the routine use of tetracyclines in conjunction with the treatment of periodontitis is unnecessary. However, their distinctive characteristics can be utilized in different delivery systems as an adjunctive aid to conventional treatment of juvenile and refractory forms of periodontitis.

Retention, antimicrobial activity, and clinical outcomes following use of a bioerodible tetracycline gel in moderate-to-deep periodontal pockets

This randomized, examiner masked, split mouth study evaluated a new model to test periodontal therapy involving a novel bioerodible copolymer gel containing tetracycline hydrochloride. Responses to the tetracycline gel and untreated control were compared for product tolerance and 3 different measures of effectiveness (drug retention, changes in microbial levels, and clinical status). The test gel was administered by syringe into the periodontal pockets of 18 systemically healthy adult volunteers, each of whom presented with 3 or more sites with 6 mm probing depths. Gingival crevicular fluid samples were used to monitor daily drug levels over 7 days, while clinical responses were assessed at day 30. Overall, the test gel was well-tolerated by all patients. For the 3 effectiveness measures, tetracycline was released throughout the observation period and mean levels exceeded 100 microg/mL over 6 days, statistically significant reductions in selected periodontal pathogens were evident at day 7 but not at day 30, and mean probing depth reductions at test sites were 1.12 mm at 30 days versus 0.36 mm at untreated control sites (P=0.012). The safety profile, longer-term drug retention, antimicrobial activity, and clinical response in this Phase I study suggest that this tetracycline-containing copolymer gel platform may represent a safe and effective bioerodible therapy for periodontitis. The experimental model also shows merit for early phase clinical testing of novel therapeutic agents.

The use of tetracycline-containing controlled-release fibers in the treatment of refractory periodontitis

The purpose of this study was to evaluate the safety and clinical efficacy of controlled-release tetracycline-containing fibers in patients with refractory periodontitis versus the preceding classical treatment. One hundred twenty-one sites in 20 patients were followed from baseline to 6 months after fiber insertion. Each selected site was > or = 5 mm deep and bled on probing. All 20 patients had at least one site > or = 7 mm which bled on probing. Those pockets remained after intense and repeated conventional therapy (scaling and root planing and often surgery), often including the use of systemic antibiotics. This treatment period, the so-called control period, preceded the experimental period by at least 3 years, when the fibers were placed. Both treatments (in control and test period) were performed in the Department of Periodontology at the University Hospital in Leuven. At the start of the experimental period, all pockets > or = 5 mm were treated by the placement of fibers impregnated with 25% tetracycline. The fibers were removed after 10 days. Probing depth, clinical attachment level, gingival recession, and bleeding on probing were recorded at baseline, and at 1, 3, and 6 months following treatment. Analysis of data from all sites indicated that a significant decrease in probing depth and gain in attachment were present at all follow-up visits. The mean probing depth reduction for sites > or = 7 mm was 3.2 mm at month 6, with a gain in attachment of 2.7 mm, while this was -1.0 mm and -1.9 mm, respectively, during the preceding control period. The fraction of bleeding pockets was reduced from 77% to 27% and from 80% to 77% during the experimental and control periods, respectively. No significant adverse side-effects were observed, except for a transient redness at fiber removal in 2 sites. Fiber insertion appeared to be time-consuming even when the operator was familiarized with the procedure. The results of this study prove that tetracycline-impregnated fibers can reduce probing depth significantly for a period of 6 months in patients not responding to thorough and repeated classical periodontal treatment.

Multi-center comparative evaluation of subgingivally delivered sanguinarine and doxycycline in the treatment of periodontitis. II. Clinical results

The clinical safety and effectiveness of a subgingivally delivered biodegradable drug delivery system containing either 10% doxycycline hyclate (DH), 5% sanguinarium chloride (SC) or no agent (VC) was evaluated in a 9-month multi-center trial. The study was a randomized parallel design with 180 patients who demonstrated moderate to severe periodontitis. All patients had at least two quadrants with a minimum of four qualifying pockets > or = 5 mm that bled on probing. Two of the qualifying pockets were required to be > or = 7 mm. At baseline and at 4 months all qualified sites were treated with the test article administered via syringe. Probing depth reduction (PDR), attachment level gain (ALG), bleeding on probing reduction (BOP), and plaque index were determined monthly. Analysis of efficacy data from the 173 efficacy-evaluable patients indicated that all treatments gave significant positive clinical changes from baseline at all subsequent timepoints. DH was superior to SC and VC in PDR at all timepoints (P < or = 0.01 to 0.001) with a maximum reduction of 2.0 mm at 5 months. For ALG, DH was superior to VC at months 2, 3, 4, 5, 6, 8, and 9 (P < or = 0.04 to 0.002) and superior to SC at months 5, 6, 7, 8, and 9 (P < or = 0.01 to 0.001) with a maximum ALG of 1.2 mm at 6 months. For BOP reduction, DH was superior to VC at all time points (P < or = 0.05) and to SC at months 3, 5, 6, 8, and 9 (P < or = 0.03). For DH, the maximum ALG in deep (> or = 7 mm) pockets was 1.7 mm and PDR 2.9 mm compared to 0.8 mm and 1.6 mm, respectively for moderate (5 to 6 mm) pockets. Test articles were applied without anesthesia and no serious adverse events occurred in the trial. The results of this study indicate that 10% doxycycline hyclate delivered in a biodegradable delivery system is an effective means of reducing the clinical signs of adult periodontitis and exhibits a benign safety profile.

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.

Tetracyclines in the management of periodontal diseases. A review

Periodontal diseases essentially comprise a group of oral infections whose primary aetiological factor is dental plaque. Removal of the cause (and its effects) is the primary aim of both non-surgical and surgical treatment regimens, although the infective nature of the diseases has led to the widespread use of antimicrobials as an adjunct to mechanical debridement. The tetracyclines are primarily bacteriostatic agents that are effective against many Gram-negative species including putative periodontopathogens such as Actinobacillus actinomycetemcomitans (A.a.). The proven efficacy of this group of drugs in the management of periodontal diseases may be related not only to their antibacterial actions, but to a number of additional properties that have been recently identified. These include collagenase inhibition, anti-inflammatory actions, inhibition of bone resorption and their ability to promote the attachment of fibroblasts to root surfaces. Consequently, tetracyclines have also been used as an adjunct to bone grafting in periodontal defects, and as agents for 'conditioning' root surfaces to enhance the regeneration of periodontal tissues. When tetracyclines are taken orally, consideration must be given both to the potential unwanted effects and to interactions with other drugs that are taken concurrently. Such problems are minimised however, when the drugs are incorporated into controlled, slow-release formulations which are currently being researched and marketed for intra-oral use.

Evidence of a direct relationship between neutrophil collagenase activity and periodontal tissue destruction in vivo: role of active enzyme in human periodontitis

To assess the temporal relationship between periodontal tissue destruction and the activity of collagenase, exudate from inflamed periodontal tissues was collected and latent and active collagenase activities were measured by a functional assay in a longitudinal cohort study. Comparisons were made between human subjects with either: 1) inflammation with a previous history of progressive loss of connective tissue and bone support (n = 14); 2) inflammation and previous history of bone loss but now clinically stable (n = 27); or 3) inflammation and no loss of bone support (n = 17). Experiments using specific enzyme inhibitors, blocking antibodies and SDS-PAGE fluorograph to identify the pattern of collagen substrate degradation demonstrated that the collagenase activity was derived from neutrophils and not from bacteria or other host cells. Active collagenase activity pooled from 6 sites per subject was respectively 5 and 6-fold higher in the group with progressive loss of connective tissue compared to the groups with either inflamed tissues alone or with inflammation and previous bone loss. In contrast, latent collagenase was increased up to 2 fold higher in the group with inflammation but no bone loss compared to the group with progressive lesions. Moreover, the ratio of active to total collagenase activity was 50% higher in the group with progressive lesions. Although in all subjects successive measurements of site-specific active collagenase 1 month apart demonstrated wide variation (r < 0.50), only in sites with progressive periodontal destruction was there significant increase of active collagenase with time (1.28 x 10(-4) collagenase units per day). There were also sharp elevations in active enzyme level at the time of detection of loss of connective tissue attachment in specific sites of 8 subjects. At the time of detection of connective tissue attachment loss, there was an overall 40% increase of pooled active collagenase activity in all subjects with progressive loss of connective tissue compared to pre-breakdown sampling times. These data provide strong in vivo evidence for a direct role of active neutrophil collagenase in the pathological destruction of periodontal connective tissue.

Clinical and microbiological effects of controlled-release locally delivered minocycline in periodontitis

The clinical efficacy of minocycline in a subgingival local delivery system was evaluated alone (M) or as an adjunct to scaling and root planing (M + SRP), in comparison to scaling and root planing (SRP) or to no subgingival treatment (NoTx) in adult periodontitis. Fifty-one adult patients with > or = 7 mm periodontal pockets demonstrating the presence by culture of Porphyromonas gingivalis (Pg), Prevotella intermedia (P(i)), or Actinobacillus actinomycetemcomitans (Aa) were randomized into one of the above 4 treatment groups. All sites > or = 5 mm in the most diseased quadrant in each patient received the therapy. Other quadrants were not treated. All patients received standardized oral hygiene instructions at the beginning of the study. At 0, 1, 3 and 6 months following therapy the 7 mm experimental sites were evaluated for selected periodontal pathogens by DNA probe analysis. At these same time points, the plaque index, gingival index, and bleeding on probing were evaluated as well as probing depth and relative clinical attachment level which were assessed by means of an automated probe. Probing depth reduction with M + SRP was significantly greater than all other groups at one month and significantly greater than NoTx and SRP at 3 months. There were no differences in probing depth reduction among groups at 6 months. At 6 months the gain in clinical attachment level was significantly greater for SRP than for either the NoTx or M groups. The prevalence of Pg decreased significantly in the M and M + SRP groups at one month.(ABSTRACT TRUNCATED AT 250 WORDS)

Report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The committee screened several hundred articles, citing 518 published papers. Some are present quality in research, others provide clinical interest, and some are identified as misleading. New techniques in pulp physiology and pathology are reported. Laser use and techniques in prevention, restorative dentistry, and materials use are reported. Epidemiology of selected diseases and the results of various formulations for treatment are cited. Diagnosis of craniomandibular dysfunction is well represented as well as references to literature reviews and other sophisticated scientific investigation. Research on adhesives is presented in respect to bonding agents for dentin and enamel. Several clinical studies are included, along with customary laboratory reports on several materials.

Serial doxycycline and metronidazole in prevention of recurrent periodontitis in high-risk patients

The efficacy of metronidazole and doxycycline in preventing recurrent periodontitis was studied in 23 patients. After treatment in the previous 7 months with either bimonthly scaling and 3 weeks of systemic doxycycline (11 subjects) or scaling and placebo (12 subjects), patients were monitored for recurrent periodontitis and were scaled every 2 months. When either a periodontal abscess or greater than 2 mm loss of gingival attachment was observed, metronidazole was administered (250 mg every 8 hours) for 10 days. In the placebo plus metronidazole group, 5 patients (42%) exhibited recurrent periodontitis after the metronidazole regimen compared with only one (9%) in the doxycycline plus metronidazole group (P less than 0.096). Subgingival plaque samples at study and healthy control sites were screened for the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Eikenella corrodens, and Fusobacterium nucleatum by immunofluorescence and for spirochetes using Ryu's stain. Presence/absence analysis of the sum of scores of the 6 individual pathogens demonstrated large reductions (P less than 0.005) in the frequency of detection of pathogens in the former doxycycline compared with the placebo plus metronidazole group at both study and control sites before and one month after metronidazole. By 7 months after metronidazole, there was no detectable difference between groups. These results indicate that prevention of recurrent periodontitis with metronidazole may be enhanced by previous treatment with doxycycline.

Collagenase activity in recurrent periodontitis: relationship to disease progression and doxycycline therapy

Previous reports have suggested that active progression of periodontitis may be correlated with increased collagenolytic activity, and that improved clinical conditions after tetracycline treatment may be explained by inhibition of host collagenase. Eighty-two patients with a recent history of periodontal abscesses and/or loss of gingival attachment level (GAL) despite active periodontal therapy were enrolled in a double-blind, randomized, placebo-controlled trial. Clinical measurements, sampling of gingival crevicular fluid (GCF) and subgingival scaling were performed every 2 months. If any site exhibited greater than 2 mm loss of GAL or a periodontal abscess, patients were administered either 100 mg doxycycline per day for 3 weeks or placebo. During 12 months of monitoring, 55 patients exhibited recurrent active disease and were then randomly assigned to either the doxycycline (n = 30) or placebo (n = 25) groups. Analysis of active collagenase and latent collagenase in GCF samples were determined by functional assays and quantitated after SDS-PAGE and fluorography. Collagenase activities were assayed at sites exhibiting active destruction (study site), at sites with pocket depth comparable to the study site but without active destruction, and at healthy sites. Clinical measurements of GAL and collagenase activity were made at intervals between 1 wk and 7 months after completion of the drug regime. Within 7 months, 15 out of 19 patients on placebo exhibited recurrent disease compared to 13 out of 29 patients on doxycycline. Collagenase activity exhibited large variations among patients and was analyzed as presence or absence of active collagenase with a logistic model.(ABSTRACT TRUNCATED AT 250 WORDS)