Azithromycin as an adjunct to scaling and root planing in the treatment of Porphyromonas gingivalis-associated periodontitis: a pilot study

Change in clinical parameters after subgingival instrumentation for the treatment of periodontitis and timing of periodontal re-evaluation: A systematic review and meta-analysis

AIM

To evaluate the changes in periodontal parameters (reduction in probing pocket depth [PPD], gain in clinical attachment level [CAL] and reduction in full-mouth bleeding on probing [BoP]) after subgingival instrumentation of periodontal pockets at different time points in systemically healthy patients suffering from periodontitis.

MATERIALS AND METHODS

Four databases were searched for RCTs that carried out subgingival instrumentation in periodontal pockets and evaluated PPD at a minimum of two consecutive time points other than baseline. The analysis was conducted for both all pocket depths and stratified for initially shallow (4-5 mm) and deep (≥6 mm) pockets and data were extracted for various time points, 1-2, 3-4 and 5-6 months. Weighted mean effects (WMEs) were calculated with 95% confidence interval (CI) and predictive intervals were calculated.

RESULTS

Twenty-nine RCTs were identified, and all of them were included in the meta-analysis. The results showed that for both shallow and deep pockets there was a small though clinically meaningful change between 1- to 2-month and 3- to 4-month time points and between these and 5-6 months.

CONCLUSIONS

In systemically healthy patients, the greater part of reduction in PPD and gain in CAL occurs within the first 1-2 months after subgingival instrumentation. However, additional benefits in terms of pocket depth reduction occur beyond these early time points.

Personalized antibiotic selection in periodontal treatment improves clinical and microbiological outputs

Introduction

Periodontitis is a biofilm-mediated disease that is usually treated by non-surgical biofilm elimination with or without antibiotics. Antibiotic treatment in periodontal patients is typically selected empirically or using qPCR or DNA hybridization methods. These approaches are directed towards establishing the levels of different periodontal pathogens in periodontal pockets to infer the antibiotic treatment. However, current methods are costly and do not consider the antibiotic susceptibility of the whole subgingival biofilm.

Methods

In the current manuscript, we have developed a method to culture subgingival samples ex vivo in a fast, label-free impedance-based system where biofilm growth is monitored in real-time under exposure to different antibiotics, producing results in 4 hours. To test its efficacy, we performed a double-blind, randomized clinical trial where patients were treated with an antibiotic either selected by the hybridization method (n=32) or by the one with the best effect in the ex vivo growth system (n=32).

Results

Antibiotic selection was different in over 80% of the cases. Clinical parameters such as periodontal pocket depth, attachment level, and bleeding upon probing improved in both groups. However, dental plaque was significantly reduced only in the group where antibiotics were selected according to the ex vivo growth. In addition, 16S rRNA sequencing showed a larger reduction in periodontal pathogens and a larger increase in health-associated bacteria in the ex vivo growth group.

Discussion

The results of clinical and microbiological parameters, together with the reduced cost and low analysis time, support the use of the impedance system for improved individualized antibiotic selection.

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 indocyanine green and methylene blue mediated-photodynamic therapy on peri-implant outcomes among diabetics with peri-implant mucositis

BACKGROUND

This study aimed to assess the efficacy of indocyanine green (ICG)-mediated versus methylene blue (MB)-mediated photodynamic therapy (PDT) as an adjunct to conventional mechanical debridement (MD) on the peri‑implant clinical, radiographic, microbiological, and immunological outcomes among diabetics with peri‑implant mucositis (pi-M).

METHODS

For this 3-month follow-up study, diabetics having pi-M were randomly divided into 3 groups: group-I (n = 20) subjects received only MD; group-II (n = 20) participants received ICG-mediated adjunct PDT; and group-III (n = 20) subjects received MB-mediated adjunct PDT. Peri-implant clinical (i.e., plaque index [PI], bleeding on probing [BOP], probing depth [PD]), radiographic (crestal bone loss [CBL]), microbiological (Fusobacterium nucleatum [F. nucleatum], Tannerella forsythia [T. forsythia], Prevotella intermedia [P. intermedia], Porphyromonas gingivalis [P. gingivalis], Aggregatibacter actinomycetemcomitans [A. actinomycetemcomitans]), and immunological (interleukin [IL]-6, IL-1β, tumor necrosis factor-alpha [TNF-α]) outcomes were assessed at baseline and 3-month follow-up.

RESULTS

Mean changes between baseline and 3-month follow-up in peri‑implant clinico-radiographic parameters were significantly different between control (PI: 12.42±21.80%; BOP: 12.10±19.30%; PD: 0.45±0.41 mm; CBL: 1.10±1.02 mm) and test groups (ICG-mediated PDT [PI: 26.55±25.80%; BOP: 28.77±29.24%; PD: 0.84±0.62 mm; CBL: 1.98±1.85 mm] and MB-mediated PDT [PI: 27.24±26.15%; BOP: 27.71±28.16%; PD: 0.85±0.63 mm; CBL: 1.95±1.80 mm]), however comparable differences were observed in peri‑implant PI, BOP, PD, and CBL between group-II and group-III participants (p>0.05). The proportions of T. forsythia were significantly reduced in group-II (4.78 × 10⁴ colony-forming unit per milliliter [CFU/mL]) and group-III (4.76 × 10⁴ CFU/mL) as compared to group-I (-4.40 × 10³ CFU/mL) at 3-month follow-up (p = 0.02). No statistically significant differences were observed between the study groups regarding the proportions of the other assessed target bacterial species. For IL-6 (group-I: 210±108; group-II: 298±165; group-III: 277±121 pg/mL; p = 0.03), IL-1β (group-I: 101±95; group-II: 84±98; group-III: 86±74 pg/mL; p = 0.02), and TNF-α (group-I: 336±121; group-II: 385±210; group-III: 366±198 pg/mL; p = 0.03) peri‑implant sulcular fluid [PISF] levels, all three study groups demonstrated statistically significant reduction at 3-month follow-up.

CONCLUSIONS

ICG-mediated and MB-mediated adjunctive PDT showed statistically significant improvements in peri‑implant clinical, radiographic, microbiological, and immunological parameters as compared to conventional MD alone at 3-month follow-up among diabetics with pi-M. However, comparable outcomes were demonstrated by ICG-mediated and MB-mediated adjunctive PDT regarding the assessed peri‑implant parameters.

Quantitative Analysis of Periodontal Pathogens Using Real-Time Polymerase Chain Reaction (PCR)

The quantitative polymerase chain reaction (qPCR) is a variant of PCR aimed to detect and quantify a targeted DNA molecule. This is made through the addition of probes labeled with fluorescent molecules that emit fluorescence within each amplification cycle, resulting in fluorescence values proportional to the amount of accumulated PCR product. This chapter presents the detailed procedures for quantification of different periodontal pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Campylobacter rectus, Streptococcus oralis, and Fusobacterium spp.) using qPCR. It also includes the description of the most frequent problems encountered, how to solve them, and recommendations to minimize the risks for laboratory staff handling oral samples. In addition, a detailed protocol for multiplex qPCR to detect and quantify Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Tannerella forsythia is also included.

Influence of Anti-Infective Periodontal Therapy on Subgingival Microbiota Evaluated by Chair-Side Test Compared to qPCR—A Clinical Follow-Up Study

A chair-side test (CST) for five periodontal pathogens (Aggregatibacter actinomycetemcomitans, A.a.; Porphyromonas gingivalis, P.g.; Prevotella intermedia, P.i.; Treponema denticola, T.d.; Tannerella forsythia, T.f.) was compared with qPCR in a previous clinical study on 100 periodontitis patients at first diagnosis (T0). Following non-surgical treatment alone (SRP) or in combination with systemic or local antibiotics, 74 patients (57.4 ± 13.5 years) were again tested at the same sites from 14 to 24 months after T0. Bacterial elimination (%; compared to T0) was determined for each single species and compared between both test systems. In all patients, all five pathogens could not be fully eliminated regardless of therapy or test method. Tested with CST, the mean elimination ranged from 90% for SRP + Amoxicillin/Metronidazole to 59.13% for SRP only. The corresponding qPCR values were 30% and 29.6%. Only A.a. was eradicated in 100% by SRP + Amoxicillin/Metronidazole tested by CST, and it was 80% when qPCR was the test method. CST agreed with qPCR in 98.7% in the detection of A.a., and 74.3%, 78.4%, 73.0%, and 48.7% for P.g., P.i., T.d., and T.f., respectively. Neither conventional treatment nor the additional use of antibiotics—even with the correct indication—could completely eradicate the tested pathogens or prevent pocket reinfection.

Elimination of Porphyromonas gingivalis inhibits liver fibrosis and inflammation in NASH

AIM

Non-alcoholic steatohepatitis (NASH) is a critical liver disease showing potential progression to liver cirrhosis/cancer. Previously, we had reported that odontogenic infection of Porphyromonas gingivalis (P. gingivalis), a major periodontal pathogen, exacerbates fibrosis in NASH through the production of fibrosis mediators such as transforming growth factor-β1 (TGF-β1) and galectin-3. In this study, we determined the effects of therapeutic interventions using antibiotics on NASH progression induced by P. gingivalis odontogenic infection.

MATERIALS AND METHODS

To eliminate P. gingivalis infection, the macrolide antibiotic [azithromycin (AZM)] was applied locally and/or systemically to a high-fat-diet-induced NASH mouse model with P. gingivalis odontogenic infection. After treatment with AZM, liver and periodontal tissues were analysed with focus on inflammation markers such as tumour necrosis factor-α (TNF-α)/Tnf-α and interleukin-1β (IL-1β)/Il-1β, and fibrosis markers such as galectin-3, phosphorylated Smad2 (pSmad2; key signalling molecule of TGF-β1), and the number of hepatic crown-like structures (hCLSs). Further, Non-alcoholic Fatty Liver Disease Activity Score (NAS), a common histological scoring system, and fibrosis area were evaluated.

RESULTS

P. gingivalis odontogenic infection significantly increased the expression of Tnf-α, Il-1β, galectin-3, and pSmad2, the number of hCLSs, and NAS score, whereas the elimination of P. gingivalis odontogenic infection, especially local with or without systemic application, significantly inhibited them.

CONCLUSION

This study suggests that elimination of P. gingivalis odontogenic infection inhibited NASH progression induced by the infection.

Short-term efficacy of a gel containing propolis extract, nanovitamin C and nanovitamin E on peri-implant mucositis: A double-blind, randomized, clinical trial

OBJECTIVE

To determine the efficacy of a gel containing propolis extract, nanovitamin C and nanovitamin E as adjuvant to mechanical debridement in the treatment of peri-implant mucositis (PM).

BACKGROUND

Propolis has anti-inflammatory and antibacterial effect that may improve peri-implant health.

METHODS

A randomized, double-blind study was performed on patients with at least one implant with PM. Participants received a professional prophylaxis and were instructed to use either test or a control gel as toothpaste three times/day for 1 month. Clinical and microbiological parameters were evaluated. PM resolution was considered in absence of bleeding on probing (BOP). Data were analysed with Mann-Whitney U, Wilcoxon signed-rank and chi-square tests.

RESULTS

Forty-six patients participated (23 in each group). After treatment, 26.1% of test patients showed complete PM resolution versus 0% in control group (p = .02). Significant reductions were observed in plaque index (p = .03), BOP (p = .04) and probing depths (p = .027) in test compared with control group. The reduction in Tannerella forsythia was statistically greater in test than in control group at 1-month follow-up (p = .02). Porphyromonas gingivalis was statistically reduced in test group from baseline to 1-month follow-up (p = .05).

CONCLUSION

Test gel clinically improved PM and showed certain antimicrobial effect after 1 month in comparison with control group. Further long-term clinical trials are required to confirm these results.

Systemic azithromycin as an adjunct to scaling and root planing in patients with stage III/IV periodontitis: 12-month results of a randomized controlled clinical trial

OBJECTIVES

To determine whether azithromycin (AZI) as an adjunct to scaling and root planing (SRP), when compared to placebo, decreases the number of sites demonstrating pocket depth (PD) ≥ 5 mm and bleeding on probing (BOP) 12 months post-treatment in stage III/IV periodontitis patients.

MATERIALS AND METHODS

In a double-blind randomized parallel-arm placebo-controlled trial, 40 stage III/IV periodontitis patients received steps 1 and 2 of periodontal treatment in two sessions within 7 days. Patients then received systemic antibiotic therapy (n = 20; AZI 500 mg/day, 3 days) or placebo (n = 20). Additional instrumentation of residual diseased sites (DS) - sites with PD ≥ 5 mm and BOP - was performed at the 3-, 6- and 9-month follow-ups. The primary outcome variable was the number of DS at the 12-month re-evaluation. Using a multivariate multilevel logistic regression model, the effects of gender, age, antibiotic therapy, presence of Porphyromonas gingivalis or Aggregatibacter actinomycetemcomitans, smoking, tooth being a molar and interdental location were evaluated.

RESULTS

The number of DS after 12 months was similar in the test (median (Me) = 4, interquartile range (IQR) = 0-6) and control (Me = 3, IQR = 1-6.5) groups. Both groups showed substantial but equivalent improvements in periodontal parameters, with no intergroup differences at initially shallow or deep sites. The logistic regression showed a lower odds ratio (OR) for the healing of DS on molars (OR = 0.29; p < 0.001) and in smokers (OR = 0.36; p = 0.048).

CONCLUSION

Stage III/IV periodontitis patients showed significant but comparable improvements in periodontal parameters and the number of residual DS at the 12-month revaluation regardless of treatment type. This may have been the result of the additional instrumentation received by patients at residual DS in both treatment groups.

CLINICAL RELEVANCE

Treatment with AZI + SRP provided no additional benefits after 12 months in terms of periodontal parameters or the number of persisting sites with PD ≥ 5 mm + BOP as compared to SRP plus placebo.

TRIAL REGISTRATION

EUDRA-CT: 2015-004306-42; https://www.clinicaltrialsregister.eu/ctr-search/trial/2015-004306-42/SI , registered 17. 12. 2015.

Adjunctive systemic antimicrobials in the treatment of chronic periodontitis: A systematic review and network meta-analysis

The aim of this systematic review and network meta-analysis was to assess the efficacy of antimicrobials adjunctive to scaling and root planing (SRP) in the treatment of chronic periodontitis. The study was conducted according to the PRISMA statement. The protocol (CRD42020178621) was registered on the International Prospective Register of Systematic Reviews (PROSPERO). The MEDLINE, EMBASE, and CENTRAL databases were searched up to March 2020; furthermore, a manual search of relevant periodontal journals was conducted. Mean differences (MD) and standard deviations were calculated for clinical attachment level (CAL) gain and probing depth (PD) reduction at 6 and 12 months. A network meta-analysis was performed to assess direct and indirect comparisons and to establish a ranking of treatments. A total of 21 randomized clinical trials (RCTs) were included in the systematic review. Network meta-analysis showed that SRP + amoxicillin (AMX) + metronidazole (MTZ), as compared to SRP, reached the highest PD reduction at 6 [MD = 0.47; 95% CI (0.3; 0.64)] and 12 months [MD = 0.51; 95% CI (0.25; 0.78)], and CAL gain at 6 [MD = 0.54; 95% CI (0.27; 0.8)] and 12 months [MD = 0.37; 95% CI (0.05; 0.69)]. Network meta-analysis indicated that AMX + MTZ adjunctive to SRP provided the best improvement in clinical parameters, followed by SRP + MTZ.

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.

Adjunctive systemic antimicrobials for the non-surgical treatment of periodontitis

BACKGROUND

Systemic antimicrobials can be used as an adjunct to mechanical debridement (scaling and root planing (SRP)) as a non-surgical treatment approach to manage periodontitis. A range of antibiotics with different dosage and combinations are documented in the literature. The review follows the previous classification of periodontitis as all included studies used this classification.

OBJECTIVES

To assess the effects of systemic antimicrobials as an adjunct to SRP for the non-surgical treatment of patients with periodontitis.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases to 9 March 2020: Cochrane Oral Health's Trials Register, CENTRAL, MEDLINE, and Embase. The US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) which involved individuals with clinically diagnosed untreated periodontitis. Trials compared SRP with systemic antibiotics versus SRP alone/placebo, or with other systemic antibiotics.

DATA COLLECTION AND ANALYSIS

We selected trials, extracted data, and assessed risk of bias in duplicate. We estimated mean differences (MDs) for continuous data, with 95% confidence intervals (CIs). We assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 45 trials conducted worldwide involving 2664 adult participants. 14 studies were at low, 8 at high, and the remaining 23 at unclear overall risk of bias. Seven trials did not contribute data to the analysis. We assessed the certainty of the evidence for the 10 comparisons which reported long-term follow-up (≥ 1 year). None of the studies reported data on antimicrobial resistance and patient-reported quality of life changes. Amoxicillin + metronidazole + SRP versus SRP in chronic/aggressive periodontitis: the evidence for percentage of closed pockets (MD -16.20%, 95% CI -25.87 to -6.53; 1 study, 44 participants); clinical attachment level (CAL) (MD -0.47 mm, 95% CI -0.90 to -0.05; 2 studies, 389 participants); probing pocket depth (PD) (MD -0.30 mm, 95% CI -0.42 to -0.18; 2 studies, 389 participants); and percentage of bleeding on probing (BOP) (MD -8.06%, 95% CI -14.26 to -1.85; 2 studies, 389 participants) was of very low certainty. Only the results for closed pockets and BOP showed a minimally important clinical difference (MICD) favouring amoxicillin + metronidazole + SRP. Metronidazole + SRP versus SRP in chronic/aggressive periodontitis: the evidence for percentage of closed pockets (MD -12.20%, 95% CI -29.23 to 4.83; 1 study, 22 participants); CAL (MD -1.12 mm, 95% CI -2.24 to 0; 3 studies, 71 participants); PD (MD -1.11 mm, 95% CI -2.84 to 0.61; 2 studies, 47 participants); and percentage of BOP (MD -6.90%, 95% CI -22.10 to 8.30; 1 study, 22 participants) was of very low certainty. Only the results for CAL and PD showed an MICD favouring the MTZ + SRP group. Azithromycin + SRP versus SRP for chronic/aggressive periodontitis: we found no evidence of a difference in percentage of closed pockets (MD 2.50%, 95% CI -10.19 to 15.19; 1 study, 40 participants); CAL (MD -0.59 mm, 95% CI -1.27 to 0.08; 2 studies, 110 participants); PD (MD -0.77 mm, 95% CI -2.33 to 0.79; 2 studies, 110 participants); and percentage of BOP (MD -1.28%, 95% CI -4.32 to 1.76; 2 studies, 110 participants) (very low-certainty evidence for all outcomes). Amoxicillin + clavulanate + SRP versus SRP for chronic periodontitis: the evidence from 1 study, 21 participants for CAL (MD 0.10 mm, 95% CI -0.51 to 0.71); PD (MD 0.10 mm, 95% CI -0.17 to 0.37); and BOP (MD 0%, 95% CI -0.09 to 0.09) was of very low certainty and did not show a difference between the groups. Doxycycline + SRP versus SRP in aggressive periodontitis: the evidence from 1 study, 22 participants for CAL (MD -0.80 mm, 95% CI -1.49 to -0.11); and PD (MD -1.00 mm, 95% CI -1.78 to -0.22) was of very low certainty, with the doxycycline + SRP group showing an MICD in PD only. Tetracycline + SRP versus SRP for aggressive periodontitis: we found very low-certainty evidence of a difference in long-term improvement in CAL for the tetracycline group (MD -2.30 mm, 95% CI -2.50 to -2.10; 1 study, 26 participants). Clindamycin + SRP versus SRP in aggressive periodontitis: we found very low-certainty evidence from 1 study, 21 participants of a difference in long-term improvement in CAL (MD -1.70 mm, 95% CI -2.40 to -1.00); and PD (MD -1.80 mm, 95% CI -2.47 to -1.13) favouring clindamycin + SRP. Doxycycline + SRP versus metronidazole + SRP for aggressive periodontitis: there was very low-certainty evidence from 1 study, 27 participants of a difference in long-term CAL (MD 1.10 mm, 95% CI 0.36 to 1.84); and PD (MD 1.00 mm, 95% CI 0.30 to 1.70) favouring metronidazole + SRP. Clindamycin + SRP versus metronidazole + SRP for aggressive periodontitis: the evidence from 1 study, 26 participants for CAL (MD 0.20 mm, 95% CI -0.55 to 0.95); and PD (MD 0.20 mm, 95% CI -0.38 to 0.78) was of very low certainty and did not show a difference between the groups. Clindamycin + SRP versus doxycycline + SRP for aggressive periodontitis: the evidence from 1 study, 23 participants for CAL (MD -0.90 mm, 95% CI -1.62 to -0.18); and PD (MD -0.80 mm, 95% CI -1.58 to -0.02) was of very low certainty and did not show a difference between the groups. Most trials testing amoxicillin, metronidazole, and azithromycin reported adverse events such as nausea, vomiting, diarrhoea, mild gastrointestinal disturbances, and metallic taste. No serious adverse events were reported.

AUTHORS' CONCLUSIONS

There is very low-certainty evidence (for long-term follow-up) to inform clinicians and patients if adjunctive systemic antimicrobials are of any help for the non-surgical treatment of periodontitis. There is insufficient evidence to decide whether some antibiotics are better than others when used alongside SRP. None of the trials reported serious adverse events but patients should be made aware of the common adverse events related to these drugs. Well-planned RCTs need to be conducted clearly defining the minimally important clinical difference for the outcomes closed pockets, CAL, PD, and BOP.

Impact of periodontal therapy on systemic markers of inflammation in patients with metabolic syndrome: A randomized clinical trial

AIM

To determine the impact of periodontal treatment on systemic markers of inflammation in patients with metabolic syndrome (MetS) and periodontitis.

MATERIALS AND METHODS

In this parallel-arm, double-blind, randomized controlled clinical trial, 63 patients with MetS and severe periodontitis were randomly assigned to receive either intensive periodontal treatment (IPT; scaling and root planing plus azithromycin 500 mg every day for 3 days) or minimal periodontal treatment (MPT; supragingival professional mechanical plaque removal plus a placebo). The primary outcome was the impact of the tested interventions on high-sensitivity C-reactive protein (hs-CRP) serum levels at 6 months. As secondary outcomes, differences in the levels of cytokines, markers of prothrombotic states, carbohydrate and lipid metabolism, as well as blood pressure, were measured at 3 and 6 months after therapy.

RESULTS

The intention-to-treat population consisted of 63 subjects randomly assigned to either the MPT (n = 31) or the IPT (n = 32) group. At baseline, mean hs-CRP was 3.9 mg/L (standard deviation [SD] = 2.9) and 3.9 mg/L (SD = 3.4), respectively, and no significant differences in cardiometabolic risk profiles were detected between the groups. Adjusting for baseline hs-CRP, sex, age, smoking status and body mass index, hs-CRP at 6 months was 1.2 mg/L (95% CI 0.4; 2.0; P = .004) lower in the IPT group than in the MPT group. In the secondary outcomes, significant reductions in IL-1β, TNF-α, HbA1c and blood pressure were observed in the IPT group at 3 months compared with the MPT group.

CONCLUSION

Effective periodontal treatment significantly reduced hs-CRP after 6 months in patients with MetS and severe periodontitis. Periodontal therapy might be useful to reduce cardiovascular risk in these patients.

Influence of adjunctive azithromycin on microbiological and clinical outcomes in periodontitis patients: 6-month results of randomized controlled clinical trial

BACKGROUND

Our aim was to determine if azithromycin therapy, as an adjunct to scaling and root planing (SRP), decreases the number of pathobiontic subgingival plaque species and sites demonstrating pocket depth (PD) ≥ 5 mm and bleeding on probing (BOP) 6 months post-treatment.

METHODS

In a double-blind randomized parallel-arm placebo-controlled trial, 40 patients received nonsurgical periodontal treatment in two sessions within 7 days. Patients then received systemic antibiotic therapy (n = 20, azithromycin 500 mg/day for 3 days) or placebo (n = 20). Pooled microbiologic samples were taken before and 6 months after therapy and analysed by established culture methods. The primary outcome variable was the number of sites with PD ≥ 5 mm and BOP at the 6-month re-evaluation. Using multivariate multilevel logistic regression, the effects of gender, age, antibiotic therapy, presence of P. gingivalis or A. actinomycetemcomitans, smoking, tooth being a molar and interdental location were evaluated.

RESULTS

The number of sites with PD ≥ 5 mm and BOP after 6 months was similar in the test (Me = 4, IQR = 0-11) and control (Me = 5, IQR = 1-22) group. Adjunctive azithromycin treatment, compared to SRP alone, resulted in more frequent eradication of A. actinomycetemcomitans (p = 0.013) and C. rectus (p = 0.029), decreased proportion (p = 0.006) and total counts (p = 0.003) of P. gingivalis, and decreased proportion of C. rectus (p = 0.012). Both groups showed substantial but equivalent improvements in periodontal parameters, with no intergroups differences at initially shallow or deep sites. The logistic regression showed a lower odds ratio for healing of diseased sites on molars (OR = 0.51; p <  0,001).

CONCLUSION

Despite significant changes in numbers of A. actinomycetemcomitans, P. gingivalis and C. rectus, patients with periodontitis do not benefit from adjunctive systemic azithromycin in terms of number of persisting sites with PD ≥ 5 mm and BOP.

TRIAL REGISTRATION

EUDRA-CT: 2015-004306-42; https://www.clinicaltrialsregister.eu/ctr-search/trial/2015-004306-42/SI , registered 17. 12. 2015.

Effect of compliance during periodontal maintenance therapy on levels of bacteria associated with periodontitis: A 6-year prospective study

BACKGROUND

It is well established that regular compliance during periodontal maintenance therapy (PMT) maintains the stability of periodontal clinical parameters obtained after active periodontal therapy (APT). However, compliance during PMT has not yet been related to subgingival bacterial levels. Thus, this study followed individuals in PMT over 6 years and longitudinally evaluated the effects of compliance on periodontitis-associated bacterial levels and its relation to periodontal status.

METHODS

From a 6-year prospective cohort study with 212 individuals in PMT, 91 were determined to be eligible. From this total, 28 regular compliers (RC) were randomly selected and matched for age and sex with 28 irregular compliers (IC). Complete periodontal examination and microbiological samples were obtained 5 times: T1 (prior to APT), T2 (after APT), T3 (2 years), T4 (4 years), and T5 (6 years). Total bacteria counts and levels of Actinomyces naeslundii, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola were evaluated through quantitative polymerase chain reaction.

RESULTS

RC had less tooth loss and better clinical and microbiological conditions over time when compared with IC. IC had higher total bacterial counts and higher levels of T. denticola. Moreover, among IC, total bacterial counts were positively associated with plaque index and bleeding on probing, while levels of A. naeslundii, T. forsythia, and T. denticola were negatively associated with clinical attachment loss (4 to 5 mm) among RC.

CONCLUSIONS

Compliance positively influenced subgingival microbiota and contributed to stability of periodontal clinical status. Regular visits during PMT sustained microbiological benefits provided by APT over a 6-year period.

Disease severity, debridement approach and timing of drug modify outcomes of adjunctive azithromycin in non-surgical management of chronic periodontitis: a multivariate meta-analysis

Background

Past meta-analyses have shown adjunctive systemic Azithromycin (AZI) to provide minor clinical benefits in scaling and root surface debridement (S/RSD). However, these have not considered the covariance of key outcome parameters; probing pocket depth (PPD) and Clinical Attachment Level (CAL) or systematically examined some potential sources of heterogeneity.

Aim

To jointly synthesize 6-month outcomes of systemic AZI as adjunctive to S/RSD in chronic periodontitis and investigate 3 potential sources of heterogeneity.

Methods

Four databases were searched for suitable randomized controlled clinical trials (RCTs). Standardized mean differences (SMD) in PPD and CAL between AZI + S/RSD and S/RSD alone, at 6-month follow-up were computed. Within-study covariances of PPD and CAL were derived from reported multiple time-point data. A multivariate meta-analysis with random effects jointly modelled PPD and CAL, factoring in their covariance. This model included 3 moderators with interaction effects; timing of AZI initiation (pre-therapy/post-therapy), type of S/RSD [full-mouth debridement (FMD)/partial-mouth debridement (PMD)], and baseline study-level mean values of PPD/CAL.

Results

Among 276 abstracts, 11 observations from 9 RCTs qualified for meta-analysis. Within-study correlation-coefficients of PPD with CAL significantly increased with increasing study-level baseline mean values (Spearman’s r = 0.79, p < 0.01). The full multivariate meta-analysis model showed significant effects for the 3 moderators (Q statistic = 150.03, p < 0.01), retained significant residual heterogeneity (Q statistic = 88.50, p < 0.01) but outperformed (Likelihood- ratio statistic = 102.95, p < 0.01,) a null-model with no moderators (Q statistic = 201.5, p < 0.01). A significant effect was seen only on the SMD for PPD (estimate = 1.16 mm, 95% CI: 0.27 mm–2.07 mm mm, p = 0.01) but not CAL (estimate = 0.17 mm, 95% CI: -0.92 mm-1.26 mm, p = 0.76). SMD in PPD positively interacted with study baseline value (estimate = 0.11, 95% CI: 0.08–0.15, p < 0.01). Significant negative interactions of SMD in PPD with PMD (estimate = − 1.25 mm, 95% CI: -1.73 mm- -0.78 mm, p < 0.01) and pre-therapy drug initiation (estimate = − 1.18 mm, 95% CI: -1.48 mm--0.87 mm, p < 0.01) were evident.

Conclusion

Joint synthesis of PPD and CAL showed, at 6-months, AZI + S/RSD provided a benefit over S/RSD alone for PPD alone when correlation with CAL was accounted for. Deeper study-level baseline PPD, FMD type of S/RSD, and post-therapy drug initiation associated with greater PPD reduction.

Electronic supplementary material

The online version of this article (10.1186/s12903-019-0754-0) contains supplementary material, which is available to authorized users.

Detection and quantification of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans in bacteremia induced by interdental brushing in periodontally healthy and periodontitis patients

OBJECTIVE

This study was aimed to compare the presence and amounts of bacteremia induced by interdental brushing in periodontally healthy (H) and periodontitis (P) individuals using culture based (direct culture [DC]) and molecular based techniques (real-time quantitative polymerase chain reaction [qPCR]) in a cross-sectional study model.

MATERIALS AND METHODS

After a full mouth periodontal evaluation, blood samples were taken before and 1 min after professionally-administered interdental brushing. These samples were analyzed by DC and qPCR, targeting Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Subgingival samples were also collected and analyzed. Student t-test, chi-squar tests and correlations were used for analyzing the data.

RESULTS

Thirty individuals per group were included. P. gingivalis and A. actinomycetemcomitans were detected with qPCR methods, but not with DC. At baseline, bacteremia was observed in 5 P patients (16.7%) and in 2 H individuals (6.6%) (p = 0.421). After interdental brushing, bacteremia was only observed in 2 P patients (6.6%) (p = 0.901). A positive correlation between subgingival and blood levels of A. actinomycetemcomitans was observed (r = 0.3; p = 0.013).

CONCLUSION

Bacteremia related to A. actinomycetemcomitans and P. gingivalis did not significantly increase after a single session of use of interdental brushes.

Microbiological and clinical effects of probiotics and antibiotics on nonsurgical treatment of chronic periodontitis: a randomized placebo- controlled trial with 9-month follow-up

Objective

The aim of this double-blind, placebo-controlled and parallel- arm randomized clinical trial was to evaluate the effects of Lactobacillus rhamnosus SP1-containing probiotic sachet and azithromycin tablets as an adjunct to nonsurgical therapy in clinical parameters and in presence and levels of Tannerella forsythia, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans.

Material and Methods

Forty-seven systemically healthy volunteers with chronic periodontitis were recruited and monitored clinically and microbiologically at baseline for 3, 6 and 9 months after therapy. Subgingival plaque samples were collected from four periodontal sites with clinical attachment level ≥1 mm, probing pocket depth ≥4 mm and bleeding on probing, one site in each quadrant. Samples were cultivated and processed using the PCR technique. Patients received nonsurgical therapy including scaling and root planing (SRP) and were randomly assigned to a probiotic (n=16), antibiotic (n = 16) or placebo (n = 15) group. L. rhamnosus SP1 was taken once a day for 3 months. Azithromycin 500mg was taken once a day for 5 days.

Results

All groups showed improvements in clinical and microbiological parameters at all time points evaluated. Probiotic and antibiotic groups showed greater reductions in cultivable microbiota compared with baseline. The placebo group showed greater reduction in number of subjects with P. gingivalis compared with baseline. However, there were no significant differences between groups.

Conclusions

The adjunctive use of L. rhamnosus SP1 sachets and azithromycin during initial therapy resulted in similar clinical and microbiological improvements compared with the placebo group.

Comparison of adjunctive azithromycin and amoxicillin/metronidazole for patients with chronic periodontitis: preliminary randomized control trial

BACKGROUND

There are insufficient guidelines for the use of adjunctive systemic antibiotics for patients with periodontal disease. The aim of this study was to compare clinical outcomes for patients with moderate-advanced chronic periodontitis treated with: scaling and root planing (SRP), SRP with amoxicillin and metronidazole (A+M), SRP with Azithromycin (Az).

METHODS

Thirty-seven non-smokers with generalized moderate to advanced chronic periodontitis were divided into three treatment groups: SRP, A+M and Az. Patients received the medications after the last SRP session and were reviewed three months later. Changes in clinical parameters were compared between the groups. Separate analyses were executed for: 'all sites', 'molar sites', 'sites with different PPD severities' and 'number of sites with shallow, moderate and deep PPD'.

RESULTS

The three groups exhibited improvements in most clinical parameters. At three months, A+M showed a higher reduction in PPD compared to Az in the 'all sites analysis'. Molars exhibited better reduction in BOP and PPD with A+M than SRP. Pocket depth of the 4-6 mm category reduced more in the A+M than SRP. A+M experienced a higher increase in the number of sites with PPD 1-3 mm than Az.

CONCLUSIONS

Adjunctive systemic antibiotics in the initial phase of treatment may result in improved clinical outcomes.

Antibiotics/antimicrobials: systemic and local administration in the therapy of mild to moderately advanced periodontitis

This review gives an update of the current scientific evidence on the efficacy of the adjunctive use of systemic and local antibiotics/antimicrobials in the treatment of periodontitis. In particular, it addresses whether their use can improve the results of nonsurgical mechanical therapy in mild-to-moderate forms of the disease. Large numbers of randomized clinical trials and systematic reviews with meta-analyses have clearly established that adjunctive systemic antibiotics, combined with mechanical debridement, offer clinical improvements additional to those obtained with scaling and root planing alone. These effects are more pronounced in aggressive periodontitis and in initially deep pockets, whereas more limited additional improvements, of 0.3 mm for additional pocket reduction and 0.2 mm for additional clinical attachment gain, have been documented for moderately deep sites (4-6 mm) in patients with chronic periodontitis. The marginal clinical benefit in patients with moderate disease has to be balanced against possible side effects. Notably, it has to be realized that an increasing number of warnings have been articulated against the unrestricted use of antibiotics in treating periodontal diseases because of the emerging global public health issue of bacterial resistance. The effects of the adjunctive local administration of antimicrobials have also been very well documented in several systematic reviews. Overall, in persistent or recurrent localized deep sites, the application of antimicrobials by sustained-delivery devices may offer a benefit of an additional 0.4 mm in pocket depth reduction and 0.3 mm in clinical attachment level gain. In conclusion, the slight additional benefits of adjunctive antimicrobials, which were shown for moderate forms of periodontitis, have to be balanced against their side effects and therefore their prescription should be limited as much as possible.

Azithromycin buccal patch in treatment of chronic periodontitis

Aim:

This study aims to explore the clinical, microbiological, and biochemical impact of azithromycin (AZM) buccal patch in chronic generalized patients as a monotherapy as well as an adjunct to nonsurgical therapy.

Materials and Methods:

A parallel design was used forty periodontitis patients were randomly allocated into five groups, namely Group 1 scaling root planing (SRP) alone, Group 2 (SRP + AZM patch group), Group 3 (SRP + AZM tablet group), Group 4 (AZM patch monotherapy), and Group 5 (AZM tablet as monotherapy). Plaque index, gingival bleeding index, modified gingival index, probing pocket depth (PPD), and clinical attachment level (CAL) were assessed at baseline and 21 and 90 days. Subgingival pooled plaque sample was collected to assess periodontopathogens like Porphyromonas gingivalis and Prevotella intermedia (Pi) by anaerobic culture method. Tumor necrosis factor alpha (TNF-α) was also evaluated at baseline and 21 days. Periodontal maintenance was performed in Group 1 until 90^th day, and clinical parameter was assessed at the end of 90^th day.

Results:

SRP + AZM tablets showed greater reduction in clinical parameters (P < 0.05) AZM as monotherapy did not offer clinical benefits over SRP. Baseline data were compared at the end, i.e., 90^th day a significant reduction in plaque scores, gingival bleeding, and PPD was observed however no significant gain in the clinical attachment was observed.

Conclusion:

The monotherapy resulted in no improvement of periodontal parameters, microbial parameters, and TNF-α level. It is safe to use AZM + SRP as a mode of nonsurgical treatment in periodontitis patients.

Systemic antibiotics in the treatment of periodontitis

Despite the fact that several clinical studies have shown additional benefits when certain systemic antibiotics are used as adjuncts to periodontal treatment, clear guidelines for the use of these agents in the clinical practice are not yet available. Basic questions concerning the use of systemic antibiotics to treat periodontitis remain unanswered, such as: which drug(s) should be used; which patients would most benefit from treatment; which are the most effective protocols (i.e. doses and durations); and in which phase of the mechanical therapy should the drug(s) be administered? Although not all of those questions have been directly addressed by controlled randomized clinical trials, recent concepts related to the ecology of periodontal diseases, as well as the major advances in laboratory and clinical research methods that have occurred in the past decade, have significantly broadened our knowledge in this field. This article endeavored to provide a 'state of the art' overview on the use of systemic antibiotics in the treatment of periodontitis, based on the most recent literature on the topic as well as on a compilation of data from studies conducted at the Center of Clinical Trials at Guarulhos University (São Paulo, Brazil) from 2002 to 2012.

Azithromycin as an adjunct to non-surgical periodontal therapy: a systematic review

The aim of this study was to investigate the current published work relating to the clinical benefits of the use of systemic azithromycin as an adjunct to non-surgical periodontal therapy. A published work search of PubMed, EMBASE and Cochrane Register of Controlled Trials up to 27 April 2016 was undertaken. The large degree of heterogeneity in the types of studies, treatment protocols, test subjects, sample size and exclusion criteria indicated that the use of narrative synthesis of all relevant studies was a valid method of review. Of the 194 eligible studies, 15 were found to be of relevance. The majority of studies demonstrated an additional clinical benefit when azithromycin is used as an adjunct to non-surgical periodontal therapy, particularly in deeper pockets (≥6 mm). In conclusion, the current body of research on the adjunctive use of systemic azithromycin in non-surgical periodontal therapy suggests there is a clinical benefit and that this benefit is greatest in deeper initial pockets (≥6 mm). The findings also suggest that future studies need to be more careful in subject selection to identify susceptible patients or at risk sites, both the immunoregulatory effects and antibiotic resistance of azithromycin needs to be reported, and that study populations need to be more homogeneous.

Systematic review and meta-analysis on the nonsurgical treatment of chronic periodontitis by means of scaling and root planing with or without adjuncts

BACKGROUND

Conduct a systematic review and meta-analysis on nonsurgical treatment of patients with chronic periodontitis by means of scaling and root planing (SRP) with or without adjuncts.

METHODS

A panel of experts convened by the American Dental Association Council on Scientific Affairs conducted a search of PubMed (MEDLINE) and Embase for randomized controlled trials of SRP with or without the use of adjuncts with clinical attachment level (CAL) outcomes in trials at least 6 months in duration and published in English through July 2014. The authors assessed individual study bias by using the Cochrane Risk of Bias Tool and conducted meta-analyses to obtain the summary effect estimates and their precision and to assess heterogeneity. The authors used funnel plots and Egger tests to assess publication bias when there were more than 10 studies. The authors used a modified version of the US Preventive Services Task Force methods to assess the overall level of certainty in the evidence.

RESULTS

The panel included 72 articles on the effectiveness of SRP with or without the following: systemic antimicrobials, a systemic host modulator (subantimicrobial-dose doxycycline), locally delivered antimicrobials (chlorhexidine chips, doxycycline hyclate gel, and minocycline microspheres), and a variety of nonsurgical lasers (photodynamic therapy with a diode laser, a diode laser, neodymium:yttrium-aluminum-garnet lasers, and erbium lasers).

CONCLUSIONS AND PRACTICAL IMPLICATIONS

With a moderate level of certainty, the panel found approximately a 0.5-millimeter average improvement in CAL with SRP. Combinations of SRP with assorted adjuncts resulted in a range of average CAL improvements between 0.2 and 0.6 mm over SRP alone. The panel judged the following 4 adjunctive therapies as beneficial with a moderate level of certainty: systemic subantimicrobial-dose doxycycline, systemic antimicrobials, chlorhexidine chips, and photodynamic therapy with a diode laser. There was a low level of certainty in the benefits of the other included adjunctive therapies. The panel provides clinical recommendations in the associated clinical practice guideline.

Quantitative Analysis of Periodontal Pathogens Using Real-Time Polymerase Chain Reaction (PCR)

The quantitative polymerase chain reaction (qPCR) is a variant of PCR aimed to detect and quantify a targeted DNA molecule through the addition of probes labeled with fluorescent molecules that emit fluorescence within each amplification cycle, what results in fluorescence values proportional to the amount of accumulated PCR product. This chapter presents the detailed procedures for quantification of different periodontal pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Campylobacter rectus, and Fusobacterium spp.) using qPCR. It also includes the description of the most frequent problems encountered and how to solve them. In addition, a detailed protocol for multiplex qPCR to detect and quantify P. gingivalis and A. actinomycetemcomitans is included.

Effectiveness of systemic antimicrobial therapy in combination with scaling and root planing in the treatment of periodontitis: a systematic review

BACKGROUND

The use of systemic antibiotics in conjunction with scaling and root planing (SRP) may improve the clinical outcome and even could be essential for a successful treatment of periodontitis. However, the effectiveness and clinical safety of this combination of therapy remain unclear. The authors of this study reviewed the available literature related to this hypothesis, evaluating the effectiveness of the use of systemic antimicrobials in combination with SRP versus SRP alone in the treatment of chronic periodontitis (CP) or aggressive periodontitis (AgP).

METHODS

The authors used 3 electronic databases and hand searched articles published from April 2001 through October 2013 in selected journals. The authors selected clinical trials with a minimum of 6 months follow-up during which patients with either CP or AgP had been treated with systemic antibiotics plus SRP in comparison with SRP alone or with placebo. The authors analyzed the gain in clinical attachment level (CAL), reduction in probing pocket depth (PPD), reduction in bleeding on probing (BOP), and patient-related variables (that is, adverse effects).

RESULTS

After the selection process, the authors included 23 clinical trials in this review. Assessment of the quality of the studies revealed the risk of bias as a common finding. Overall, there was a tendency toward improvement of the measured outcomes, CAL, PPD, and BOP in studies for which systemic antibiotics were used as adjunctive therapy with SRP.

CONCLUSION

Owing to the high level of heterogeneity of the studies included in this review, the authors could not establish definitive conclusions and guidelines regarding the use of adjunctive systemic antibiotics. However, within the limitations of this review, the use of systemic antibiotics with SRP may be beneficial for specific populations. Standardized clinical disease diagnostic criteria and additional randomized controlled clinical trials are necessary to verify the effectiveness of the use of adjunctive systemic antimicrobials with SRP.

PRACTICAL IMPLICATIONS

Owing to methodological differences and biases among clinical trials evaluating systemic antibiotics adjunctive to SRP, clinicians should base their decisions to prescribe on the results of weighing both benefits and risks for each patient.

Clinical Efficacy of Azithromycin as an Adjunctive Therapy to Non-Surgical Periodontal Treatment of Periodontitis: A Systematic Review and Meta-Analysis

INTRODUCTION

Over the years, numerous trials have sufficiently documented benefits of adjuvant administration of antibiotics in combination to Scaling and Root Planing (SRP) in treatment of periodontitis. Nevertheless there are justified doubts in respect to antibiotics administration with regard to increasing development of resistances.

AIM

The aim of this review study and meta-analysis was to verify a possible benefit of Azithromycin (AZM) as an alternative adjuvant antibiotic in combination with SRP.

MATERIALS AND METHODS

Electronic databases (Pubmed) were searched from the earliest point of record until May 2015. A hand search was also conducted. The variables considered in this respect were Probing Depth (PD), Clinical Attachment Level (CAL), Bleeding on Probing (BOP) and SRP. A meta-analysis containing trials comparing SRP as a sole therapy with SRP and administration of AZM was produced once all of the data obtained had been reviewed.

RESULTS

Six randomised clinical trials were accepted into the review and the meta-analysis following the process of trial selection. Meta-analysis revealed larger overall effects by the systemic administration of AZM compared with SRP on their own in terms of PD, CAL, BOP, Plaque-Index and total bacterial load reduction after three and six months.

CONCLUSION

The data used in this study revealed that the systemic administration of AZM is beneficial compared with SRP on its own for the treatment of chronic periodontitis.

Herpes Simplex Virus Type 1 and Other Pathogens are Key Causative Factors in Sporadic Alzheimer's Disease

This review focuses on research in epidemiology, neuropathology, molecular biology, and genetics regarding the hypothesis that pathogens interact with susceptibility genes and are causative in sporadic Alzheimer's disease (AD). Sporadic AD is a complex multifactorial neurodegenerative disease with evidence indicating coexisting multi-pathogen and inflammatory etiologies. There are significant associations between AD and various pathogens, including Herpes simplex virus type 1 (HSV-1), Cytomegalovirus, and other Herpesviridae, Chlamydophila pneumoniae, spirochetes, Helicobacter pylori, and various periodontal pathogens. These pathogens are able to evade destruction by the host immune system, leading to persistent infection. Bacterial and viral DNA and RNA and bacterial ligands increase the expression of pro-inflammatory molecules and activate the innate and adaptive immune systems. Evidence demonstrates that pathogens directly and indirectly induce AD pathology, including amyloid-β (Aβ) accumulation, phosphorylation of tau protein, neuronal injury, and apoptosis. Chronic brain infection with HSV-1, Chlamydophila pneumoniae, and spirochetes results in complex processes that interact to cause a vicious cycle of uncontrolled neuroinflammation and neurodegeneration. Infections such as Cytomegalovirus, Helicobacter pylori, and periodontal pathogens induce production of systemic pro-inflammatory cytokines that may cross the blood-brain barrier to promote neurodegeneration. Pathogen-induced inflammation and central nervous system accumulation of Aβ damages the blood-brain barrier, which contributes to the pathophysiology of AD. Apolipoprotein E4 (ApoE4) enhances brain infiltration by pathogens including HSV-1 and Chlamydophila pneumoniae. ApoE4 is also associated with an increased pro-inflammatory response by the immune system. Potential antimicrobial treatments for AD are discussed, including the rationale for antiviral and antibiotic clinical trials.

Relative effectiveness of azithromycin in killing intracellular Porphyromonas gingivalis

Invasive infections by Porphyromonas gingivalis are associated with persistent periodontal attachment loss and can be difficult to eliminate by scaling and root planing. Azithromycin (AZM) inhibits P. gingivalis and is actively accumulated by most human cells. We used an in vitro infection model to compare the effectiveness of AZM in killing intracellular P. gingivalis to the combined regimen of amoxicillin (AMX) and metronidazole (MET). Transport of [3H]-AZM by human gingival fibroblasts was characterized. Monolayers of Smulow-Glickman gingival epithelial cells or gingival fibroblasts were infected with P. gingivalis (strain 33277 or W83). After extracellular bacteria were eliminated with teicoplanin, infected cells were treated with therapeutic concentrations of AZM, AMX, or AMX + MET. Viable intracellular bacteria were released by cell lysis and plated on blood agar for enumeration. Antimicrobial activity against planktonic P. gingivalis was also evaluated. While survival of intraepithelial P. gingivalis 33277 was not significantly different after treatment with the three regimens, survival in infected fibroblasts was significantly lower after AZM treatment (65.9 ± 5.5%) compared with AMX (92.2 ± 3.5%) or AMX + MET (79.8 ± 5.2%, P < 0.01). Carnitine, a competitive inhibitor of AZM transport, reduced killing by AZM by ~55% (P < 0.05). Survival of intrafibroblast P. gingivalis W83 was also significantly lower after AZM treatment compared with the other regimens (P < 0.05). At therapeutic concentrations, AZM was significantly more active against intracellular P. gingivalis than against planktonic P. gingivalis (P < 0.0083). Gingival epithelial cells and fibroblasts possess a transport system that accumulates AZM and enhances elimination of intracellular P. gingivalis. Compared with the combination of AMX and MET, AZM was equally effective against intraepithelial P. gingivalis 33277 and significantly more effective against both strains of P. gingivalis from infected gingival fibroblasts. The results suggest that AZM could be a reasonable alternative to the regimen of AMX and MET for periodontal patients who should not take these agents due to known side effects or compliance issues.

Azithromycin enhances phagocytic killing of Aggregatibacter actinomycetemcomitans Y4 by human neutrophils

BACKGROUND

Aggregatibacter actinomycetemcomitans resists killing by neutrophils and is inhibited by azithromycin (AZM) and amoxicillin (AMX). AZM actively concentrates inside host cells, whereas AMX enters by diffusion. The present study is conducted to determine whether AZM is more effective than AMX at enhancing phagocytic killing of A. actinomycetemcomitans by neutrophils.

METHODS

Killing assays were conducted in the presence of either 2 μg/mL AZM or 16 μg/mL AMX (equipotent against A. actinomycetemcomitans). Neutrophils were loaded by incubation with the appropriate antibiotic. Opsonized A. actinomycetemcomitans strain Y4 was incubated with the indicated antibiotic alone, with loaded neutrophils and antibiotic, or with control neutrophils (without antibiotic) at multiplicities of infection (MOIs) of 30 and 90 bacteria per neutrophil.

RESULTS

Neutrophil incubation with 2 μg/mL AZM yielded an intracellular concentration of 10 μg/mL. At an MOI of 30, neutrophils loaded with AZM failed to kill significantly more bacteria than control neutrophils during the 60- and 90-minute assay periods. At an MOI of 90, neutrophils loaded with AZM killed significantly more bacteria than either AZM alone or control neutrophils during 60- and 90-minute incubations (P < 0.05), and killed significantly more bacteria after 90 minutes than the sum of the killing produced by AZM alone or neutrophils alone. Neutrophils incubated with AMX under identical conditions also killed significantly more bacteria than either AMX alone or control neutrophils, but there was no evidence of synergism between AMX and neutrophils.

CONCLUSIONS

Neutrophils possess a concentrative transport system for AZM that may enhance killing of A. actinomycetemcomitans. Its effects are most pronounced when neutrophils are greatly outnumbered by bacteria.

Microbiological and Clinical Effects of Sitafloxacin and Azithromycin in Periodontitis Patients Receiving Supportive Periodontal Therapy

Sitafloxacin (STFX) is a newly developed quinolone that has robust antimicrobial activity against periodontopathic bacteria. We previously reported that oral administration of STFX during supportive periodontal therapy was as effective as conventional mechanical debridement under local anesthesia microbiologically and clinically for 3 months. The aim of the present study was to examine the short-term and long-term microbiological and clinical effects of systemic STFX and azithromycin (AZM) on active periodontal pockets during supportive periodontal therapy. Fifty-one patients receiving supportive periodontal therapy were randomly allocated to the STFX group (200 mg/day of STFX for 5 days) or the AZM group (500 mg/day of AZM for 3 days). The microbiological and clinical parameters were examined until 12 months after the systemic administration of each drug. The concentration of each drug in periodontal pockets and the antimicrobial susceptibility of clinical isolates were also analyzed. The proportions of red complex bacteria, i.e., Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, which are the representative periodontopathic bacteria, were significantly reduced at 1 month and remained lower at 12 months than those at baseline in both the STFX and AZM groups. Clinical parameters were significantly improved over the 12-month period in both groups. An increase in the MIC of AZM against clinical isolates was observed in the AZM group. These results indicate that monotherapy with systemic STFX and AZM might be an alternative treatment during supportive periodontal therapy in patients for whom invasive mechanical treatment is inappropriate. (This study has been registered with the University Hospital Medical Information Network-Clinical Trials Registry [UMIN-CTR] under registration number UMIN000007834.).

Nonsurgical therapy of chronic periodontitis with adjunctive systemic azithromycin or amoxicillin/metronidazole

OBJECTIVES

The objective of the present study is to compare the effect of systemic adjunctive use of azithromycin with amoxicillin/metronidazole to scaling and root planing (SRP) in a clinical study.

MATERIALS AND METHODS

Data from 60 individuals with chronic periodontitis were evaluated after full-mouth SRP. Antibiotics were given from the first day of SRP, in the test group (n = 29), azithromycin for 3 days and, in the control group (n = 31), amoxicillin/metronidazole for7 days. Probing depth (PD), attachment level (AL), and bleeding on probing (BOP) were recorded at baseline and after 3 and 12 months. Gingival crevicular fluid was analyzed for matrix metalloprotease (MMP)-8 and interleukin (IL)-1beta levels. Subgingival plaque was taken for assessment of the major bacteria associated with periodontitis.

RESULTS

In both groups, PD, AL, and BOP were significantly reduced (p < 0.001). A few significant differences between the groups were found; AL and BOP were significantly better in the test than in the control group at the end of the study (p = 0.020 and 0.009). Periodontopathogens were reduced most in the test group.

CONCLUSIONS

A noninferiority of the treatment with azithromycin in comparison with amoxicillin/metronidazole can be stated. The administration of azithromycin could be an alternative to the use of amoxicillin/metronidazole adjunctive to SRP in patients with moderate or severe chronic periodontitis; however, a randomized placebo-controlled multicenter study is needed.

CLINICAL RELEVANCE

Application of azithromycin as a single antibiotic for 3 days might be considered as an additional adjunctive antibiotic to SRP in selected patients.

Clinical effect of azithromycin as an adjunct to non-surgical treatment of chronic periodontitis: a meta-analysis of randomized controlled clinical trials

The results of recent published studies focusing on the effect of azithromycin as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis are inconsistent. We conducted a meta-analysis of randomized controlled clinical trials to examine the effect of azithromycin combined with SRP on periodontal clinical parameters as compared to SRP alone. An electronic search was carried out on Pubmed, Embase and the Cochrane Central Register of Controlled Trials from their earliest records through December 28, 2014 to identify studies that met pre-stated inclusion criteria. Reference lists of retrieved articles were also reviewed. Data were extracted independently by two authors. Either a fixed- or random-effects model was used to calculate the overall effect sizes of azithromycin on probing depth, attachment level (AL) and bleeding on probing (BOP). Heterogeneity was evaluated using the Q test and I(2) statistic. Publication bias was evaluated by Begg's test and Egger's test. A total of 14 trials were included in the meta-analysis. Compared with SRP alone, locally delivered azithromycin plus SRP statistically significantly reduced probing depth by 0.99 mm (95% CI 0.42-1.57) and increased AL by 1.12 mm (95% CI 0.31-1.92). In addition, systemically administered azithromycin plus SRP statistically significantly reduced probing depth by 0.21 mm (95% CI 0.12-0.29), BOP by 4.50% (95% CI 1.45-7.56) and increased AL by 0.23 mm (95% CI 0.07-0.39). Sensitivity analysis yielded similar results. No evidence of publication bias was observed. The additional benefit of systemic azithromycin was shown at the initially deep probing depth sites, but not at shallow or moderate sites. The overall effect sizes of systemic azithromycin showed a tendency to decrease with time, and meta-regression analysis suggested a negative relation between the length of follow-up and net change in probing depth (r = -0.05, p = 0.02). This meta-analysis provides further evidence that azithromycin used as an adjunct to SRP significantly improves the efficacy of non-surgical periodontal therapy on reducing probing depth, BOP and improving AL, particularly at the initially deep probing depth sites.

Non-surgical periodontal therapy supplemented with systemically administered azithromycin: a systematic review of RCTs

BACKGROUND

Azithromycin may be an alternative adjunctive systemic antibiotic in non-surgical periodontal therapy.

OBJECTIVE

This study aims to identify randomized controlled trials evaluating non-surgical periodontal treatment of chronic and/or aggressive periodontitis supplemented with systemically administered azithromycin.

MATERIALS AND METHODS

A systematic literature search was performed for publications published by 31 March 2014 using electronic databases and hand search. Randomized controlled trials published in English or German language, with a follow-up ≥6 months were included. From 231 titles identified, nine publications were eligible for inclusion.

RESULTS

Among the studies included, showing some risk of bias, seven reported on patients with chronic periodontitis and two with aggressive periodontitis. Minor adverse events were described in five studies. A synthesis of results using a vote counting method was applied. Significant (p < 0.05) beneficial effects of azithromycin were shown in six studies for probing depth changes and in five studies for clinical attachment level changes.

CONCLUSION

In contrast to aggressive periodontitis patients, data from this analysis indicate a potential benefit of systemic azithromycin as adjunctive to non-surgical periodontal therapy in chronic periodontitis patients.

CLINICAL RELEVANCE

When contraindications for the standard antibiotics are present, azithromycin (AZM) may be considered as alternative systemically administered antibiotic drug in selected cases of chronic periodontitis.

Adjunctive use of antibiotics in periodontal therapy

Periodontal diseases are infectious diseases with a mixed microbial aetiology and marked inflammatory response leading to destruction of underlying tissue. Periodontal therapy aims to eliminate pathogens associated with the disease and attain periodontal health. Periodontitis is generally treated by nonsurgical mechanical debridement and regular periodontal maintenance care. Periodontal surgery may be indicated for some patients to improve access to the root surface; however, mechanical debridement alone may not be helpful in all cases. In such cases, adjunctive systemic antibiotic therapy remains the treatment of choice. It can reach microorganisms at the base of the deep periodontal pockets and furcation areas via serum, and also affects organisms residing within gingival epithelium and connective tissue. This review aims to provide an update on clinical issues regarding when and how to prescribe systemic antibiotics in periodontal therapy. The points discussed are the mode of antibiotic action, susceptible periodontal pathogens, antibiotic dosage, antibiotic use in treatment of periodontal disease, and mechanism of bacterial resistance to each antibiotic.

Non-surgical periodontal therapy with systemic antibiotics in patients with untreated chronic periodontitis: a systematic review and meta-analysis

OBJECTIVE

The purpose of this meta-analysis is to evaluate the effectiveness of different systemic antibiotics in combination with scaling and root planing (SRP) when compared to SRP alone in patients with untreated chronic periodontitis.

BACKGROUND

Although chronic periodontitis is mostly treated without adjunctive systemic antibiotics, some recent meta-analyses have shown clinical benefit for some systemic antibiotics when used as an adjunct to SRP. However, there is a wide variety of systemic antibiotic regimens used today. It remains unclear if the selected type of systemic antibiotic influences the magnitude of clinical benefit.

MATERIAL AND METHODS

The MEDLINE-PubMed database was searched from their earliest records through May 16, 2013. Several journals were hand searched and some authors were contacted for additional information. Outcome measures analysed were mean bleeding on probing change, mean clinical attachment level gain and mean probing pocket depth reduction. Extracted data were pooled using a random effect model. Weighted mean differences were calculated and heterogeneity was assessed.

RESULTS

The search yielded 281 abstracts. Ultimately, 95 studies were selected, describing 43 studies meeting the eligibility criteria. Systemic antibiotics showed a significant (p < 0.05) additional pocket depth reduction for moderate (at 3 mo 0.27 mm ± 0.09, at 6 mo 0.23 mm ± 0.10 and at 12 mo 0.25 mm ± 0.27) and deep pockets (at 3 mo 0.62 mm ± 0.17, at 6 mo 0.58 mm ± 0.16 and at 12 mo 0.74 mm ± 0.30). Statistically, no specific type of antibiotic was superior over another. However, when analysing the clinical data for initially moderate pockets or deep pockets, some trends became apparent.

CONCLUSION

Systemic antibiotics combined with SRP offer additional clinical improvements compared to SRP alone. Although there were no statistically significant differences, there was a trend that for initially moderate and deep pockets, metronidazole or metronidazole combined with amoxicillin, resulted in clinical improvements that were more pronounced over doxycycline or azithromycin. Additionally, there was a trend that the magnitude of the clinical benefit became smaller over time (1 year).

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.

Effect of periodontal therapy on the subgingival microbiota over a 2-year monitoring period. I. Overall effect and kinetics of change

AIM

To examine the 2-year post-therapy kinetics of change in the composition of subgingival biofilms.

MATERIAL AND METHODS

In this study, 178 chronic periodontitis subjects were recruited and clinically monitored at baseline, 3, 6, 12, 18 and 24 months after therapy. All subjects received scaling and root planing and 156 one or more of periodontal surgery, systemically administered amoxicillin + metronidazole or local tetracycline at pockets ≥5 mm. Subgingival biofilm samples taken from each subject at each time point were analysed for their content of 40 bacterial species using checkerboard DNA-DNA hybridization. The significance of changes in median species counts over time was sought using the Wilcoxon or Friedman tests and adjusted for multiple comparisons.

RESULTS

Mean counts were significantly reduced from baseline to 2 years for 30 of the 40 taxa. Marked reductions were observed for periodontal pathogens including Tannerella forsythia, Treponema denticola and Eubacterium nodatum. The kinetics of change differed from species to species. When data were subset according to baseline PD, patterns of change in the microbial profiles were generally similar.

CONCLUSION

Periodontal therapy leads to a rapid reduction in periodontal pathogens, followed by a slower reduction in other taxa that can be sustained for at least 2 years.

Azithromycin suppresses human osteoclast formation and activity in vitro

Azithromycin is an antibiotic with anti-inflammatory properties used as an adjunct to treat periodontitis, a common inflammatory mediated condition featuring pathologic alveolar bone resorption. This study aimed to determine the effect of azithromycin on human osteoclast formation and resorptive activity in vitro. Osteoclasts were generated from peripheral blood mononuclear cells stimulated with macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor kappa B (RANK) ligand. The effects of azithromycin at concentrations ranging from 0.5 to 40 µg/ml were tested. Osteoclast formation and activity, acidification, actin ring formation and expression of mRNA, and protein encoding for key osteoclast genes were assessed. The results demonstrated that azithromycin reduced osteoclast resorptive activity at all concentrations tested with osteoclast formation being significantly reduced at the higher concentrations (20 and 40 µg/ml). mRNA and protein expression of key osteoclast transcription factor Nuclear Factor of Activated T cells (NFATc1) was significantly reduced by azithromycin at later stages of osteoclast development (day 17). Azithromycin also reduced tumor necrosis factor receptor associated factor-6 (TRAF6) mRNA expression at day 14, and cathepsin K mRNA expression at days 14 and 17. Integrin β3 and MMP-9 mRNA expression was reduced by azithromycin at day 17 in osteoclasts cultured on dentine. The osteoclast proton pump did not appear to be affected by azithromycin, however formation of the actin ring cytoskeleton was inhibited. This study demonstrates that azithromycin inhibits human osteoclast function in vitro, which may account for at least some of the beneficial clinical effects observed with azithromycin treatment in periodontitis.

Azithromycin: a new concept in adjuvant treatment of periodontitis

In most patients periodontitis is successfully treated by scaling and root planing, but some studies have shown that certain sites continue to show periodontal tissue destruction despite conventional periodontal therapy. To solve this problem, antibiotics may be administered as an adjuvant treatment. This includes azithromycin (AZM), which is effective against Gram-negative aerobic and anaerobic bacteria and has a long half-life in periodontal tissues. The purpose of the present study was to determine the efficacy of azithromycin as an adjuvant treatment for periodontitis through a review of the literature in Medline, Lilacs and Scielo, combining the keywords "azithromycin", "periodontal treatment" and "periodontitis" in both Portuguese and English languages. To be included, articles had to be clinical trials, randomized, controlled, double-blind or blind, and published between 2001 and 2011. 70 articles were found, of which 12 were selected based on title and abstract. Most studies used AZM as an adjuvant treatment for chronic periodontitis, usually in a single daily dose of 500 mg over three days, and indicated that AZM significantly reduced probing depth and increased periodontal attachment when compared to controls. Furthermore, a reduction in red and orange complex and an increase in bacteria associated with healthy periodontal conditions were observed in subjects treated with AZM. It may be concluded that the use of AZM as an adjuvant treatment for periodontitis improves clinical and microbiological parameters when compared to conventional treatment alone.