Drug Concentration in Inflamed Periodontal Tissues After Systemically Administered Azithromycin

Comparative Study of Azithromycin Versus Doxycycline Effect on the Resistin Level in Periodontitis Patients With Type 2 Diabetes: A Randomized Controlled Clinical Trial

AIM

The present study aimed to determine if azithromycin (AZM) and doxycycline therapy, as an adjunct to scaling and root planning (SRP), modulate host response and improve clinical outcomes in periodontitis patients with type 2 diabetes mellitus (T2DM).

PATIENTS AND METHODS

Forty-five periodontal sites in 15 periodontitis patients with T2DM received nonsurgical periodontal therapy (NSPT). In Group I, patients were placebo (not receiving any medication), Group II patients received systemic AZM therapy (AZM 250 mg/day for five days), and Group III patients received doxycycline (20 mg twice per day for three months. The resistin level was collected and measured by enzyme-linked immunosorbent assay (ELISA). Gingival index (GI), probing depth (PD), and clinical attachment level (CAL) were recorded at baseline, one-month, and three-month intervals.

RESULTS

All groups showed improvement in clinical parameters and resistin levels throughout the study. The mean resistin level at three months was the highest in Group I and the lowest in Group III. Patients in Group II showed a larger decrease in mean PD than those in Group I and III. Group III had the highest gain in mean CAL, with an increase of 1.78 mm in attachment.

CONCLUSION

Resistin might be a useful indicator of current disease status. In addition, benefits from adjunctive systemic use of AZM and doxycycline have been administered with non-surgical periodontal therapy.

Azithromycin as an adjunct to subgingival professional mechanical plaque removal in the treatment of grade C periodontitis: a systematic review and meta-analysis

The aim of this systematic review was to evaluate clinical and microbiological outcomes with the use of azithromycin as an adjunct to non-surgical subgingival professional mechanical plaque removal (PMPR) in the treatment of grade C periodontitis. Online database searches using high-level MeSH terms in a PICO structure were conducted along with hand-searching of relevant periodontal journals. Titles and abstracts of identified studies were independently reviewed by both authors and the full texts of studies meeting the inclusion criteria were independently reviewed. In total, 122 studies were identified through searches, of which 6 were included in the qualitative analysis and 4 in the meta-analysis. Three studies included in the meta-analysis were deemed at low risk of bias and 1 at serious risk. There were conflicting results on whether azithromycin reduced the number of subgingival pathogens or detectable subgingival Aggregatibacter actinomycetemcomitans between the included studies. The meta-analysis revealed a statistically significant probing depth reduction difference in favour of azithromycin compared to the control at 3 months (weighted mean difference [WMD]=−0.39 mm; 95% confidence interval [CI], −0.66 to −0.13 mm; I²=0%) and 12 months (WMD=−1.32 mm; 95% CI, −1.71 to −0.93 mm; I²=0%). The clinical attachment level change was also statistically significant in favour of azithromycin compared to the control at 3 months (WMD=−0.61 mm; 95% CI, −1.13 to −0.10 mm; I²=71%) and 12 months (WMD=−0.88 mm; 95% CI, −1.32 to −0.44 mm; I²=0%). Based upon these results, azithromycin offers additional improvements in some clinical parameters when used in conjunction with subgingival PMPR in patients with aggressive periodontitis over control groups. These improvements appear to be maintained for up to 12 months after treatment completion. However, due to a lack of well-designed studies, the conclusions that can be drawn from the available evidence are limited.

Effect of Azithromycin on Mineralized Nodule Formation in MC3T3-E1 Cells

Azithromycin displays immunomodulatory and anti-inflammatory effects in addition to broad-spectrum antimicrobial activity and is used to treat inflammatory diseases, including respiratory and odontogenic infections. Few studies have reported the effect of azithromycin therapy on bone remodeling processes. The aim of this study was to examine the effects of azithromycin on the osteogenic function of osteoblasts using osteoblast-like MC3T3-E1 cells. Cells were cultured in the presence of 0, 0.1, 1, and 10 µg/mL azithromycin, and cell proliferation and alkaline phosphatase (ALPase) activity were determined. In vitro mineralized nodule formation was detected with alizarin red staining. The expression of collagenous and non-collagenous bone matrix protein was determined using real-time PCR or enzyme-linked immunosorbent assays. In cells cultured with 10 µg/mL azithromycin, the ALPase activity and mineralized nodule formation decreased, while the type I collagen, bone sialoprotein, osteocalcin, and osteopontin mRNA expression as well as osteopontin and phosphorylated osteopontin levels increased. These results suggest that a high azithromycin concentration (10 µg/mL) suppresses mineralized nodule formation by decreasing ALPase activity and increasing osteopontin production, whereas low concentrations (≤l.0 µg/mL) have no effect on osteogenic function in osteoblastic MC3T3-E1 cells.

Effect of Azithromycin on Proinflammatory Cytokine Production in Gingival Fibroblasts and the Remodeling of Periodontal Tissue

Previous reports have shown that azithromycin (AZM), a macrolide antibiotic, affects collagen synthesis and cytokine production in human gingival fibroblasts (hGFs). However, there are few reports on the effect of AZM on human periodontal ligament fibroblasts (hPLFs). In the present study, we comparatively examined the effects of AZM on hGFs and hPLFs. We monitored the reaction of AZM under lipopolysaccharide (LPS) stimulation or no stimulation in hGFs and hPLFs. Gene expression analyses of interleukin-6 (IL-6), interleukin-8 (IL-8), matrix metalloproteinase-1 (MMP-1), matrix metalloproteinase-2 (MMP-2), and Type 1 collagen were performed using reverse transcription-polymerase chain reaction (RT-PCR). Subsequently, we performed Western blotting for the analysis of the intracellular signal transduction pathway. In response to LPS stimulation, the gene expression levels of IL-6 and IL-8 in hGFs increased due to AZM in a concentration-dependent manner, and phosphorylation of nuclear factor kappa B (NF-κB) was also promoted. Additionally, AZM caused an increase in MMP-1 expression in hGFs, whereas it did not affect the expression of any of the analyzed genes in hPLFs. Our findings indicate that AZM does not affect hPLFs and acts specifically on hGFs. Thus, AZM may increase the expression of IL-6 and IL-8 under LPS stimulation to modify the inflammatory response and increase the expression of MMP-1 to promote connective tissue remodeling.

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.

Does Probiotic Lactobacillus Have an Adjunctive Effect in the Nonsurgical Treatment of Peri-Implant Diseases? A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the additional effect of probiotic Lactobacillus in the nonsurgical management of peri-implant diseases (peri-implant mucositis and peri-implantitis).

METHODS

Six databases were searched up to May 2019 without time and language restrictions. Study selection and data extraction were conducted independently by 2 reviewers. The inclusion criteria for this systematic review were defined based on the participants, intervention, comparison, outcomes, and study design (PICOS) format. Randomized controlled trials comparing nonsurgical treatment combined with probiotic Lactobacillus or placebo agent in patients with peri-implant diseases were included. The methodological quality of retrieved studies was assessed according to the Cochrane Collaboration's Risk of Bias tool, and the quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool. Odds ratio and 95% confidence interval (CI) were used to describe dichotomous data, while mean difference and standardized mean difference with 95% CI were used to describe continuous variables.

RESULTS

Seven randomized controlled trials with 296 implants were included in this meta-analysis. The mean difference of probing pocket depth (PPD) was -0.05 (95% CI: -0.28 to 0.18; P = .67) immediately after treatment termination and -0.17 (95% CI: -1.01 to 0.67, P = .69) at least 2 months after treatment termination. There was a slight reduction of PPD after treatment termination. Compared with placebo, Lactobacillus provided limited benefits in peri-implant mucositis. There were no significant differences in the secondary outcomes of bleeding on probing or plaque index (P > .05). In a narrative synthesis of peri-implantitis, the effect of Lactobacillus on PPD and bleeding on probing remained controversial.

CONCLUSIONS

This systematic review and meta-analysis showed that probiotic Lactobacillus provide limited benefits to the nonsurgical treatment of peri-implant mucositis or peri-implantitis.

Comparing the Antimicrobial In Vitro Efficacy of Amoxicillin/Metronidazole against Azithromycin-A Systematic Review

On account of its proven clinical efficacy, the combination of systemically administered amoxicillin and metronidazole is frequently adjuncted to non-operative periodontal therapy and well documented. Potential drawbacks of this regimen, e.g., side effects and problems with the compliance, led to an ongoing search for alternatives. Azithromycin, an antibiotic extensively used in general medicine, has recently found its niche in periodontal therapy as well. This systematic review aimed to analyze the in vitro antimicrobial efficacy of amoxicillin plus metronidazole versus azithromycin. For this purpose, a systematic literature search was performed, and studies published up to 29 March 2018 referenced in Medline, Embase, Cochrane, and Biosis were independently screened by two authors. An additional hand search was performed and studies focusing on the evaluation of in vitro antimicrobial efficacy of amoxicillin + metronidazole or azithromycin on bacteria from the subgingival biofilm were included. English and German language research reports were considered. From 71 identified articles, only three articles were eligible for inclusion. These studies showed heterogeneity in terms of analytical methods and strains explored. However, all studies used multispecies biofilm models for analysis of the antimicrobial activity. Unanimously, studies reported on more pronounced antimicrobial effects when applying the combination of amoxicillin + metronidazole, compared to azithromycin. Based on the few studies available, the combination of amoxicillin + metronidazole seemed to display higher antimicrobial efficacy in vitro than azithromycin.

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.

The effects of Lactobacillus reuteri probiotics combined with azithromycin on peri-implantitis: A randomized placebo-controlled study

PURPOSE

The aim of this randomized placebo-controlled clinical study was to investigate the effects of a probiotic tablet containing Lactobacillus reuteri in peri-implantitis patients.

METHODS

Subjects comprised 30 patients with mild to moderate peri-implantitis. A baseline clinical examination and microbiological assessment were conducted, followed by an antibiotics treatment (azithromycin, 500mg, once a day for 3 days). Subjects were divided into probiotic and placebo groups. The clinical examination and bacterial sampling were performed 0, 4, 12 and 24 weeks after the intake of probiotics. The clinical examination included probing pocket depth (PPD), bleeding on probing (BOP), the modified plaque index (mPI), and modified bleeding index (mBI). The number of bacteria was assessed using the PCR-invader method. The Wilcoxon rank-sum test and Wilcoxon signed-rank test with Bonferroni corrections were used for data analyses.

RESULTS

Although the number of bacteria decreased after the administration of azithromycin in both groups, they increased again thereafter. No significant difference was observed in bacterial numbers between the two groups. Although PPD in the probiotics group was significantly lower at 4 and 24 weeks than at 0 weeks (p<0.05), a significant decrease did not occur in the placebo group. The mBI score at 24 weeks was significantly lower in the probiotics group than in the placebo group (p<0.05). No significant difference was observed in BOP or mPI between the two groups.

CONCLUSION

These results suggested that probiotics prevent inflammation by affecting host responses rather than improving microbial flora in peri-implant sulci in peri-implantitis patients.

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.

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.

The effect of systemic antibiotics administered during the active phase of non-surgical periodontal therapy or after the healing phase: a systematic review

Objective

The aim of this systematic review was to compare the clinical effectiveness of systemic antibiotics administered in the active stage of periodontal treatment or after the healing phase.

Material and Methods

An electronic search was performed in the databases EMBASE, MEDLINE and Cochrane Central Register of Controlled Trials (CENTRAL), in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement. A manual search of the reference list of selected studies and of review articles was also performed up to November 2013. Randomized Clinical Trials (RCT) that evaluated the systemic administration of antibiotics as adjuvants to scaling and root planning (SRP) at different phases of periodontal treatment were included. Systematic reviews and studies that evaluated subjects with systemic diseases and those that used subantimicrobial doses of antibiotics were excluded.

Results

The initial search identified 1,039 articles, of which seven were selected, and only one met the inclusion criteria. This study showed that subjects taking metronidazole and amoxicillin at the initial phase of treatment exhibited statistically significantly greater reduction in pocket depth and gain in clinical attachment level in initially deep sites (PD≥7 mm) than subjects taking antibiotics after healing (p<0.05). This comparison was conducted 2 months after antibiotic intake, at the healing phase.

Conclusion

To date, only one short-term RCT has directly compared different moments of systemic antibiotics administration, as adjuncts to SRP, in the treatment of periodontitis. Although the results of this study suggested some benefits for antibiotics intake during the active phase of therapy, these findings need to be confirmed by larger placebo-controlled randomized clinical trials with longer follow-up periods.

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.

Generalized Aggressive Periodontitis Associated With a Plasma Cell Gingivitis Lesion: A Case Report and Non-Surgical Treatment

INTRODUCTION

Plasma cell gingivitis (PCG) is an unusual inflammatory condition characterized by dense, band-like polyclonal plasmacytic infiltration of the lamina propria. Clinically, it appears as gingival enlargement with erythema and swelling of the attached and free gingiva and is not associated with any loss of attachment. The aim of this report is to present a rare case of severe generalized aggressive periodontitis (GAgP) associated with a PCG lesion that was successfully treated and maintained non-surgically.

CASE PRESENTATION

A 32-year-old white male with a non-contributory medical history presented with gingival enlargement with diffuse erythema and edematous swelling, predominantly around teeth #5 through #8. Clinical and radiographic examination revealed generalized severe periodontal breakdown. A complete blood count and biochemical tests were within normal limits. Histologic and immunohistochemical examination were consistent with PCG. A diagnosis of severe GAgP associated with a PCG lesion was assigned. Treatment included elimination of possible allergens and non-surgical periodontal treatment in combination with azithromycin. Clinical examination at reevaluation revealed complete resolution of gingival enlargement, erythema, and edema and localized residual probing depths of 5 mm. One year after treatment, the clinical condition was stable. Radiographs indicated improved bone levels and formation of crestal lamina dura.

CONCLUSION

This case report highlights the unusual coexistence of GAgP and PCG, in which non-surgical treatment with elimination of all possible causes in combination with antimicrobials resulted in elimination of the gingival enlargement and significant improvement of periodontal parameters.

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.

Periodontitis: a host-mediated disruption of microbial homeostasis. Unlearning learned concepts

New concepts evolve when existing ones fail to address known factors adequately or are invalidated by new evidence. For decades periodontitis has been considered to be caused by specific bacteria or groups of bacteria and, accordingly, treatment protocols have largely been based on anti-infective therapies. However, close inspection of current data leads one to question whether these bacteria are the cause or the result of periodontitis. Good evidence is emerging to suggest that it is indeed the host response to oral bacteria that leads to the tissue changes noted in gingivitis. These changes lead to an altered subgingival environment that favors the emergence of 'periodontal pathogens' and the subsequent development of periodontitis if the genetic and external environmental conditions are favorable for disease development. Thus, it seems that it is indeed the initial early host-inflammatory and immune responses occurring during the development of gingivitis, and not specific bacteria or their so-called virulence factors, which determine whether periodontitis develops and progresses. In this review we consider these concepts and their potential to change the way in which we view and manage the inflammatory periodontal diseases.

Azithromycin: mechanisms of action and their relevance for clinical applications

Azithromycin is a macrolide antibiotic which inhibits bacterial protein synthesis, quorum-sensing and reduces the formation of biofilm. Accumulating effectively in cells, particularly phagocytes, it is delivered in high concentrations to sites of infection, as reflected in rapid plasma clearance and extensive tissue distribution. Azithromycin is indicated for respiratory, urogenital, dermal and other bacterial infections, and exerts immunomodulatory effects in chronic inflammatory disorders, including diffuse panbronchiolitis, post-transplant bronchiolitis and rosacea. Modulation of host responses facilitates its long-term therapeutic benefit in cystic fibrosis, non-cystic fibrosis bronchiectasis, exacerbations of chronic obstructive pulmonary disease (COPD) and non-eosinophilic asthma. Initial, stimulatory effects of azithromycin on immune and epithelial cells, involving interactions with phospholipids and Erk1/2, are followed by later modulation of transcription factors AP-1, NFκB, inflammatory cytokine and mucin release. Delayed inhibitory effects on cell function and high lysosomal accumulation accompany disruption of protein and intracellular lipid transport, regulation of surface receptor expression, of macrophage phenotype and autophagy. These later changes underlie many immunomodulatory effects of azithromycin, contributing to resolution of acute infections and reduction of exacerbations in chronic airway diseases. A sub-group of post-transplant bronchiolitis patients appears to be sensitive to azithromycin, as may be patients with severe sepsis. Other promising indications include chronic prostatitis and periodontitis, but weak activity in malaria is unlikely to prove crucial. Long-term administration of azithromycin must be balanced against the potential for increased bacterial resistance. Azithromycin has a very good record of safety, but recent reports indicate rare cases of cardiac torsades des pointes in patients at risk.

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.

Effects of periodontal non-surgical therapy plus azithromycin on glycemic control in patients with diabetes: a randomized clinical trial

BACKGROUND AND OBJECTIVE

Periodontitis may alter the systemic condition in patients with diabetes and hence interfere with glycemic control. The objective of this study was to determine the quantifiable changes in glycated hemoglobin (HbA1C) after periodontal non-surgical therapy plus azithromycin in a mixed population of patients with poorly controlled diabetes.

MATERIALS AND METHODS

One hundred and five patients were randomized to receive non-surgical therapy plus azythromycin (AZ-Sca =33), non-surgical therapy plus placebo (PB-Sca = 37) and supragingival prophylaxis plus azithromycin (AZ-Pro = 35). Glycated hemoglobin, glycemia and periodontal parameters were measured at baseline, 3, 6 and 9 mo after treatment.

RESULTS

Periodontal parameters were improved in the AZ-Sca and PB-Sca groups as compared to the AZ-Pro group. A greater reduction in probing depth was observed in the AZ-Sca as compared to the PB-Sca group. Improvement in clinical attachment level was similar between AZ-Sca and PB-Sca groups. A reduction from 8.0% to 7.2% (∆0.8%; p < 0.05) in HbA1C was observed in the AZ-Sca at 9 mo as compared to the PB-Sca group in which the reduction was from 7.9% to 7.6% (∆0.3%). There was no decrease in HbA1C in the AZ-Pro group over time. Mean glycemia values decreased from 195 mg/dL to 159.2 mg/dL (∆35.8 mg/dL; p < 0.05) in the AZ-Sca group whereas a decrease from 194 mg/dL to 174.8 mg/dL (∆19.2 mg/dL) in the PB-Sca group at 9 mo was observed. There were no differences between the AZ-Sca and PB-Sca groups for glycemic parameters. No improvement in glycemic values in the AZ-Pro group was observed.

CONCLUSIONS

A modest improvement in glycemic control was detected with a trend towards the use of non-surgical therapy plus AZ as compared to the placebo.

Effect of gingivitis on azithromycin concentrations in gingival crevicular fluid

BACKGROUND

Macrolide antibiotics yield high concentrations in inflamed tissue, suggesting that their levels in gingival crevicular fluid (GCF) could be increased at gingivitis sites. However, the increased volume of GCF associated with gingivitis could potentially dilute macrolides. To determine whether these assumptions are correct, the bioavailability of systemically administered azithromycin was compared in GCF from healthy and gingivitis sites.

METHODS

Experimental gingivitis was induced in one maxillary posterior sextant in nine healthy individuals. Contralateral healthy sextants served as controls. Participants ingested 500 mg azithromycin, followed by a 250-mg dose 24 hours later. Four hours after the second dose, plaque was removed from experimental sites. GCF was collected from eight surfaces in both the experimental and control sextants and pooled separately. GCF samples were subsequently collected on days 2, 3, 8, and 15, and azithromycin content was determined by agar diffusion bioassay.

RESULTS

On days 2 and 3, the pooled GCF volume at experimental sites was significantly higher than at control sites (P <0.01), and the total azithromycin mass in 30-second GCF samples pooled from experimental sites was significantly higher than at control sites (P <0.02). However, there were no significant differences in azithromycin concentration between the experimental and control pools at any point. Concentrations exceeded 7.3 μg/mL on day 2 and 2.5 μg/mL on day 15.

CONCLUSION

Azithromycin concentrations are similar in GCF from gingivitis sites and healthy sites, suggesting that the processes that regulate GCF azithromycin concentration can compensate for local inflammatory changes.

Effects of systemic sitafloxacin on periodontal infection control in elderly patients

OBJECTIVE

To evaluate the microbiological and clinical effects of the systemic administration of sitafloxacin (STFX) on periodontal pockets in elderly patients receiving supportive periodontal therapy (SPT).

BACKGROUND

Periodontitis is a risk factor for atherosclerosis. Better periodontal health contributes to reduce atherosclerosis-related diseases in elderly population.

MATERIALS AND METHODS

Forty-four patients undergoing SPT were randomly assigned to two groups: a test group took 100 mg/day of STFX for five consecutive days, or a control group received scaling and root planing (SRP) under local anaesthesia. Microbiological and clinical parameters were examined at baseline and at 1 and 3 months after therapy.

RESULTS

The presence of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia was significantly reduced at 1 month after treatment in both groups. The median reductions of the bacteria between the baseline and 1 month were 3.08 and 2.54% in the STFX- and SRP-treated groups, respectively. Both treatments significantly decreased the probing depth at 1 and 3 months compared to the baseline.

CONCLUSION

The systemic administration of STFX is effective at improving periodontal health during SPT and could be an alternative to SRP for elderly patients who cannot undergo anaesthesia or are at risk of tissue injury.

Azithromycin in periodontal treatment: more than an antibiotic

Azithromycin is a macrolide antibiotic used extensively in medicine for the treatment of a wide range of infections such as upper respiratory tract infections, middle ear infections, sexually transmitted infections and trachoma. It is also effective against the most common periodontopathogens. The versatility of the macrolides extends beyond their antibiotic properties as a result of their well-documented immune-modulating/anti-inflammatory effects. Macrolides, including azithromycin, are therefore used to treat diseases not associated with bacteria, such as severe asthma, chronic obstructive pulmonary diseases and, more recently, cystic fibrosis. Azithromycin is concentrated in neutrophils, macrophages and particularly fibroblasts; all of these cells are central players in the pathogenesis of most periodontal diseases. This paper reviews the diverse properties of azithromycin and the clinical periodontal studies of its effects in both the treatment of periodontitis and in resolving drug-related gingival overgrowth. Evidence exists to support the use of a single course of azithromycin in the treatment of advanced periodontal diseases. Azithromycin could have a triple role in the treatment and resolution of periodontal diseases: suppressing periodontopathogens, anti-inflammatory activity and healing through persistence at low levels in macrophages and fibroblasts in periodontal tissues, even after a single course of three tablets. If future periodontal research confirms these properties, it could become a valuable host-modulator in periodontal treatment.

Antibiofilm effects of azithromycin and erythromycin on Porphyromonas gingivalis

Antibiotic resistance of biofilm-grown bacteria contributes to chronic infections, such as marginal and periapical periodontitis, which are strongly associated with Porphyromonas gingivalis. Concurrent azithromycin (AZM) administration and mechanical debridement improve the clinical parameters of periodontal tissue in situ. We examined the in vitro efficacy of AZM against P. gingivalis biofilms. The susceptibilities of adherent P. gingivalis strains 381, HW24D1, 6/26, and W83 to AZM, erythromycin (ERY), ampicillin (AMP), ofloxacin (OFX), and gentamicin (GEN) were investigated using a static model. The optical densities of adherent P. gingivalis cells were significantly decreased by using AZM and ERY at sub-MIC levels compared with those of the controls in all the strains tested, except for the effect of ERY on strain W83. AMP and OFX inhibited P. gingivalis adherent cells at levels over their MICs, and GEN showed no inhibition in the static model. The effects of AZM and ERY against biofilm cells were investigated using a flow cell model. The ATP levels of P. gingivalis biofilms were significantly decreased by AZM at concentrations below the sub-MICs; however, ERY was not effective for inhibition of P. gingivalis biofilm cells at their sub-MICs. Furthermore, decreased density of P. gingivalis biofilms was observed three-dimensionally with sub-MIC AZM, using confocal laser scanning microscopy. These findings suggest that AZM is effective against P. gingivalis biofilms at sub-MIC levels and could have future clinical application for oral biofilm infections, such as chronic marginal and periapical periodontitis.

Azithromycin concentrations in blood and gingival crevicular fluid after systemic administration

BACKGROUND

Azithromycin is a macrolide antibiotic that is active against several periodontal pathogens. Macrolides are taken up and concentrated inside gingival fibroblasts, which could influence their pharmacokinetics. This study tests the hypothesis that steady-state levels of azithromycin are higher and more sustained in gingival crevicular fluid (GCF) than in serum.

METHODS

Four healthy patients received an initial dose of 500-mg azithromycin followed by 250-mg doses on each of the next 2 days. Serum and GCF samples were obtained 2 hours after the last dose on day 2, and on days 4 and 7. GCF samples were collected from maxillary posterior sites with paper strips. The strips were pooled and eluted with high-purity water. After extraction, the azithromycin content of the serum samples and GCF eluates was determined with an agar diffusion bioassay.

RESULTS

On days 2, 4, and 7, the concentrations of azithromycin in blood serum were 0.22 ± 0.02, 0.08 ± 0.02, and 0.04 ± 0.01 μg/mL, respectively. The concentrations in GCF were 8.82 ± 1.25, 7.90 ± 1.72, and 7.38 ± 1.15 μg/mL, respectively. Mean GCF levels were significantly higher than mean serum levels (P ≤0.02; paired t test).

CONCLUSIONS

The findings demonstrate that the pharmacokinetic profiles of azithromycin are different in GCF and serum. At steady state, azithromycin concentrations in GCF were higher and more sustained than those in serum. Based on previous studies, the levels observed in GCF were above the minimal inhibitory concentration for Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, and Prevotella intermedia.

Azithromycin decreases crevicular fluid volume and mediator content

Azithromycin enhances the response to root planing and produces anti-inflammatory effects in treating chronic lung disease. This led us to hypothesize that azithromycin inhibits inflammatory mediator production in gingiva, leading to decreased gingival crevicular fluid (GCF) volume. To test this hypothesis, ten periodontally healthy volunteers received azithromycin every 24 hours for 48 hours. GCF samples were collected from 12 maxillary interproximal sites prior to azithromycin (baseline) and 2, 4, 7, and 14 days later. Samples were assayed for IL-1beta, IL-8, TNF-alpha, VEGF, IL-6, and IL-10. With azithromycin treatment, GCF volume decreased significantly on days 2 through 7 (P < 0.05), but increased toward baseline levels on day 14. This was accompanied by a transient decrease in the content of IL-1beta, IL-8, TNF-alpha, and VEGF (P < 0.05). IL-6 and IL-10 were not detected. Since plaque was absent throughout the study, the findings suggest that azithromycin produces anti-inflammatory effects in gingiva.

Macrolide antibiotics like azithromycin increase lipopolysaccharide-induced IL-8 production by human gingival fibroblasts

Objective

Macrolide antibiotics are reported to modulate the production of cytokines in various type of cells. We examined the effect of macrolide antibiotics on inflammatory cytokines (IL-6 and IL-8) and chemical mediator (PGE₂) and also matrix metalloproteinases (MMPs) productions by human gingival fibroblasts (HGFs) treated with lipopolysaccharide (LPS).

Methods

The effect of macrolide antibiotics [erythromycin (EM), azithromycin (AZM) and josamycin (JOM)] on HGFs proliferation were examined by MTT assay. HGFs were treated with LPS from Porphyromonas gingivalis (PgLPS) and macrolide antibiotics, and IL-6, IL-8 and PGE₂ levels were evaluated by ELISA. MMPs were detected by gelatin zymography.

Results

AZM slightly but significantly decreased HGFs proliferation, while EM and JOM did not affected. AZM increased PgLPS-induced IL-8 production dose-dependently, while AZM did not alter IL-6 and PGE₂ productions. EM and JOM did not altered PgLPS-induced IL-6, IL-8 and PGE₂ productions. All macrolide antibiotics did not alter MMPs production. These results indicate that macrolide antibiotics have no direct anti-inflammatory effect. However, the use of the inhibitors of cell signaling pathway failed to reveal the mechanism that AZM enhanced PgLPS-induced IL-8 production.

Conclusion

These results suggest macrolide antibiotics have an indirect anti-inflammatory effect as a result of their antimicrobial properties. Because AZM increased LPS-induced IL-8 production by HGFs, the possibility is considered that neutrophils may be migrated to periodontal tissue and phagocytize the periodontopathic bacteria more efficiently.

Clinical and microbiologic effects of subgingivally delivered 0.5% azithromycin in the treatment of chronic periodontitis

BACKGROUND

Recent developments suggest that the local delivery of antimicrobials into periodontal pockets can improve periodontal health. The present study was undertaken to investigate the clinical and microbiologic effectiveness of azithromycin (AZM) at 0.5% concentration in an indigenously prepared bioabsorbable controlled-release gel as an adjunct to non-surgical mechanical therapy in the treatment of chronic periodontitis.

METHODS

Eighty patients were categorized into two treatment groups: scaling and root planing (SRP) only (group 1) and SRP plus 0.5% AZM (group 2). Clinical parameters were recorded at baseline and 1, 2, and 3 months; they included modified gingival index, modified sulcus bleeding index, probing depth (PD), and clinical attachment level (CAL). At baseline and 6 and 12 weeks, microbiologic assessment was done of the percentage of morphologically different microorganisms (coccoid cells, others [straight rods, filaments, and fusiforms], motile rods, and spirochetes) using darkfield microscopy. The mean concentration of 0.5% AZM in gingival crevicular fluid was estimated by reverse phase high performance liquid chromatography.

RESULTS

Both therapies resulted in significant improvements. Mean PD reduction from baseline to 3 months was 2.13 +/- 0.35 mm and 2.53 +/- 0.52 in groups 1 and 2, respectively. Mean CAL gain from baseline to 3 months was 0.60 +/- 0.63 mm and 1.07 +/- 0.70 mm in groups 1 and 2, respectively. All microbiologic categories showed significant improvement in both groups, with greater improvement in the test group. The mean concentration of AZM at all observed periods (baseline to 28 days) provided sufficient antimicrobial activity (>2 microg/ml) and fulfilled the conditions for a controlled-release device.

CONCLUSION

Although both treatment strategies seemed to benefit the patients, the adjunctive use of 0.5% AZM as a controlled drug-delivery system enhanced the clinical and microbiologic results as shown by the intergroup comparison.