In vitro susceptibilities of suspected periodontopathic anaerobes as determined by membrane transfer assay

Effects of Rinsing with Povidone-Iodine during Step II Periodontal Therapy: A Systematic Review and Meta-Analysis

Background and Objectives: Antiseptics have been suggested to enhance the outcomes of non-surgical periodontal treatment (NSPT). Among these, povidone-iodine (PVP-iodine) was reported to significantly reduce periodontal pocket depths (PPDs). The aim of this study was to systematically re-assess the existing literature regarding the potential benefit of using PVP-iodine in step II periodontal therapy. Material and Methods: The scientific literature was systematically searched across electronic libraries for randomized controlled trials employing PVP-iodine during NSPT through to September 2023, using search items related to PVP-iodine and periodontitis. The selection process was performed by two independent reviewers. The primary outcomes were reductions in periodontal probing depth (PPD) and clinical attachment level (CAL). When reasonable, a meta-analysis of the included studies was performed. Results: Initially, 799 records were identified. After abstract and title screening and fulltext revision, 15 RCTs were included. The data from eight studies were merged in meta-analyses. The use of PVP-iodine had no significant effect on PPD reduction at 6 months (means [standard deviation]: -0.12 mm [-0.33; 0.09]) but it did at 12 months (-0.29 mm [-0.56; -0.02]). CAL was significantly better at 6 (-0.42 mm [-0.64; -0.20]) and 12 months (-0.39 mm [-0.66; -0.11]). Conclusions: PVP-iodine rinsing during NSPT may slightly improve patients' PPD and CAL.

Molecular Iodine Mouthrinse Antimicrobial Activity Against Periodontopathic Bacteria

AIM

This study compared two molecular iodine mouthrinses for their in vitro bactericidal effects against subgingival biofilm bacteria from severe periodontitis patients.

MATERIALS AND METHODS

In a subgingival biofilm eradication assay, dilution aliquots of subgingival microbial specimens from 32 adults with severe periodontitis were mixed in vitro with either a mouthrinse containing 100 parts per million (ppm) molecular iodine (Iorinse®) or one containing 150 ppm molecular iodine (iClean®), followed by mouthrinse neutralization after 60 seconds with 3% sodium thiosulfate. The mixtures, along with unexposed subgingival biofilm aliquots, were inoculated onto enriched Brucella blood agar and incubated anaerobically for 7 days to quantitate total viable bacterial counts and selected red/orange complex periodontal pathogens (Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia/nigrescens, Parvimonas micra, Campylobacter rectus, and Fusobacterium nucleatum).

RESULTS

Both molecular iodine mouthrinses significantly reduced total viable bacterial counts in the subgingival biofilm samples, with iClean® providing significantly greater in vitro suppression than Iorinse®. Both molecular iodine mouthrinses also significantly reduced total red/orange complex periodontal pathogens, with significantly greater suppression also exhibited by iClean®.

CONCLUSION

The molecular iodine mouthrinses exerted marked bactericidal activity in vitro against human subgingival biofilm microbial species, including red/orange complex periodontal pathogens associated with severe periodontitis, with iClean® providing significantly better antimicrobial activity than Iorinse®.

CLINICAL SIGNIFICANCE

These findings suggest potential value of molecular iodine mouthrinses in the treatment and prevention of periodontal diseases.

Comparison of Subgingival Irrigation Effect of Boric Acid 0.5% and Povidone-Iodine 0.1% on Chronic Periodontitis Treatment

PURPOSE

To comparatively evaluate the effect of a 5% boric acid (BA) irrigant on periodontal condition, bacterial level and oral neutrophil numbers with a 1% povidone iodine (PVP-I) irrigant as an adjunct to scaling and root planing (SRP) in chronic periodontitis (CP) treatment.

MATERIALS AND METHODS

A single-masked, randomised clinical trial with 36 CP patients was conducted at the Faculty of Odonto-Stomatology, University of Medicine and Pharmacy, Ho Chi Minh City, Vietnam. Subjects were randomly divided into two treatment groups: 1) SRP plus PVP-I 0.1% irrigant and 2) SRP plus BA 0.5% irrigant. Clinical measurements, including the plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), bacterial level in subgingival plaque (BANA test) and the quantification of oral neutrophils were evaluated at baseline, 4, 6 and 8 weeks after treatment (T0, T4, T6 and T8).

RESULTS

Whole-mouth (PI, GI, BOP, PD, CAL and PD) parameters, bacterial level in subgingival plaque and number of oral neutrophils decreased statistically significantly after treatment compared to baseline in both groups (p < 0.01). Between the two groups, whole-mouth PI, GI, BOP, PD and CAL reduction in the BA 0.5% group were higher than those in the PVP-I 0.1% group, but statistical significance was found only for GI and BOP after treatment (p < 0.05). The PD and CAL reductions for moderately deep pockets (PD ≥ 5 mm and < 7 mm) were significantly greater in group 2 compared to group 1 after treatment compared to baseline (p < 0.01). This difference was not found for deep pockets (PD ≥ 7 mm).

CONCLUSION

The results of this study suggest that BA 0.5% could be an alternative to PVP-I 0.1%, and might be more favourable because it provided superior results regarding whole-mouth BOP, GI as well as PD and CAL reduction for moderately deep pockets after CP treatment.

Non-surgical periodontal therapy: An update on current evidence

Periodontal disease is an inflammatory condition that involves a complex interaction between pathogenic bacteria, environmental and acquired factors and host related factors. Till recently periodontal treatment was directed primarily towards reduction of bacterial load by subgingival debridement of root surfaces and modification of environmental risk factors. The current paradigm of periodontal disease stresses greater role of host-mediated inflammatory response in tissue destruction characteristic of periodontal disease. Various therapeutic modalities have been developed adjuvant to mechanical periodontal therapy. The use of laser and photodynamic therapy show great promise but their effectiveness has still not been conclusively proven. Chemotherapeutic agents, either systemic and local antimicrobials or host modulating drugs, played pivotal role in better and more predictable management of periodontal disease. The present review focuses on the best available evidence, for the current management of the chronic periodontal patients, gathered from systematic reviews and meta-analysis of mechanical non surgical periodontal therapy (NSPT) (subgingival debridement, laser therapy and photodynamic therapy) and the adjunctive chemotherapeutic approaches such as systematic and local antibiotics and antiseptics, subgingival pocket irrigation and host modulation therapies. The review also attempts to briefly introduce future developments in some of these modalities. At the end, the review summarizes the analysis of the current evidence that suggests that thorough subgingival debridement remains the mainstay of NSPT and that adjunct use of chemotherapeutic agents may offer better management of clinical parameters in periodontitis patients.

Clearance of topically-applied PVP-iodine as a solution or gel in periodontal pockets in men

OBJECTIVES

The aim of the study was to investigate the clearance of PVP-iodine applied as a gel or solution in periodontal pockets.

METHODS

Teeth of 12 subjects with at least eight periodontal pockets of ≥5 mm probing depth were isolated with a rubber dam to allow contamination-free access to the pockets. In each subject, three pockets were filled with PVP-iodine gel (10%) and three with PVP-iodine solution (10%). One pocket of each subject without iodine application served as a negative control. The treatment allocation was assigned randomly. Any excess material was removed subsequently. After 1, 5 and 15 min, a paper point was used to collect the sulcus liquid and the concentration of PVP-iodine was chemically determined. In addition, PVP-iodine gel was administered into 12 periodontal pockets immediately after sub-gingival ultrasound debridement and the concentration of PVP-iodine was determined after 1 min.

RESULTS

Descending concentrations of PVP-iodine were determined at 1, 5 and 15 min after the application. No PVP-iodine was found in the pockets serving as negative controls. The mean concentrations of the gel and solution were 6.14 μg/ml and 4.44 μg/ml (1 min; p ≥ 0.028), 3.20 μg/ml and 1.44 μg/ml (5 min; p ≥ 0.126), 0.69 μg/ml and 0.23 μg/ml (15 min; p ≤ 0.019), respectively. In the pockets with previous debridement the mean concentration was 1.68 ± 1.97 μg/ml.

CONCLUSION

The application of PVP-iodine gel in periodontal pockets allows a prolonged remnant effect as compared to that of the solution formula.

Non-surgical instrumentation associated with povidone-iodine in the treatment of interproximal furcation involvements

Objective

The aim of this controlled clinical trial was to evaluate the effect of topically applied povidone-iodine (PVP-I) used as an adjunct to non-surgical treatment of interproximal class II furcation involvements.

Material and methods

Thirty-two patients presenting at least one interproximal class II furcation involvement that bled on probing with probing pocket depth (PPD) ≥5 mm were recruited. Patients were randomly chosen to receive either subgingival instrumentation with an ultrasonic device using PVP-I (10%) as the cooling liquid (test group) or identical treatment using distilled water as the cooling liquid (control group). The following clinical outcomes were evaluated: visible plaque index, bleeding on probing (BOP), position of the gingival margin, relative attachment level (RAL), PPD and relative horizontal attachment level (RHAL). BAPNA (N-benzoyl-Larginine-p-nitroanilide) testing was used to analyze trypsin-like activity in dental biofilm. All parameters were evaluated at baseline and 1, 3 and 6 months after non-surgical subgingival instrumentation.

Results

Six months after treatment, both groups had similar means of PPD reduction, RAL and RHAL gain (p>0.05). These variables were, respectively, 2.20±1.10 mm, 1.27±1.02 mm and 1.33±0.85 mm in the control group and 2.67±1.21 mm, 1.50±1.09 mm and 1.56±0.93 mm in the test group. No difference was observed between groups at none of the posttreatment periods, regarding the number of sites showing clinical attachment gain ≥2 mm. However, at 6 months posttreatment, the test group presented fewer sites with PPD ≥5 mm than the control group. Also at 6 months the test group had lower BAPNA values than control group.

Conclusion

The use of PVP-I as an adjunct in the non-surgical treatment of interproximal class II furcation involvements provided limited additional clinical benefits.

Systematic review on the effect of rinsing with povidone-iodine during nonsurgical periodontal therapy

BACKGROUND AND OBJECTIVE

The existing literature is inconsistent regarding whether there is any additional effect of povidone-iodine (PVP-iodine) as an adjunctive to scaling and root planing, and, if there is an effect, what its size is. Therefore, the aim of this study was to assess the additional effect of PVP-iodine as an adjunct to scaling and root planing compared with water, saline or no rinse in the treatment of chronic periodontitis.

MATERIAL AND METHODS

An electronic literature search of the databases PubMed, EMBASE and the Cochrane Central Library, and a handsearch, were performed (up to November 2008). Two reviewers independently identified and selected screened abstracts for possible inclusion, and assessed randomized, controlled clinical trials comparing the additional benefit of PVP-iodine with water, saline rinsing or no rinsing in the nonsurgical periodontal therapy of patients with chronic periodontitis. A fixed-effects meta-analysis was conducted in the absence of statistically significant heterogeneity.

RESULTS

A small, but statistically significant additional beneficial effect of the adjunctive use of PVP-iodine with enhanced probing pocket depth reductions of 0.28 mm (95% confidence interval: 0.08 to 0.48, p = 0.007) was found. There was no significant heterogeneity between studies (I(2) = 0%). However, most of the studies included in the meta-analysis were of low quality, and the treatment modalities showed various differences such as the use of PVP-iodine at different concentrations and application modalities. Nevertheless, single-rooted teeth, in particular, showed an additional benefit after scaling and root planing with PVP-iodine, particularly when the treatment was repeated during the healing stage.

CONCLUSION

The adjunctive use of PVP-iodine during scaling and root planing may increase the clinical pocket depth reduction, although the clinical significance is small to moderate.

Microbiological effect of the use of an ultrasonic device and iodine irrigation in patients with severe chronic periodontal disease: a randomized controlled clinical study

OBJECTIVE

Instrumentation of the subgingival area is aimed at removing as much as possible of the bacterial biofilm and subgingival calculus. Since mechanical root debridement is a technically demanding procedure, antiseptics and antibiotics delivered either locally or systemically have been used as adjunct to scaling and root-planning procedures in order to control the subgingival biofilm and thereby enhance the treatment outcome. Our aim was to study the microbiological effect of ultrasonic debridement with or without povidone-iodine (PVP-iodine) in the treatment of severe chronic periodontitis.

MATERIAL AND METHODS

Twenty patients were recruited to the study. Each test site and the related quadrant were randomly assigned to one of four different treatment modalities: ultrasonic scaling+subgingival irrigation with 0.5% PVP-iodine for 5 min/tooth, ultrasonic scaling+subgingival irrigation with sterile saline solution for 5 min/tooth, subgingival irrigation with sterile saline solution for 5 min/tooth and subgingival irrigation with 0.5% PVP-iodine for 5 min/tooth. The individuals were followed longitudinally for 6 months.

RESULTS

The present study showed that non-surgical periodontal therapy with the use of an ultrasonic device was effective in reducing the analyzed putative periodontal bacteria. No statistically significant difference between ultrasonic+saline and ultrasonic+PVP-iodine was found.

CONCLUSIONS

Ultrasonic debridement reduced the periodontal markers in patients with severe chronic periodontitis. The reduction was selective. A concentration of 0.5% PVP-iodine did not add any anti-microbiological effect compared to ultrasonic debridement alone.

Healing following ultrasonic debridement and PVP-iodine in individuals with severe chronic periodontal disease: a randomized, controlled clinical study

OBJECTIVE

Antiseptics and antibiotics delivered either locally or systemically have been used as an adjunct to scaling and root planing procedures in order to control the subgingival biofilm and thereby enhancing the treatment outcome. The results presented in the literature are, however, inconclusive. Povidone-iodine (PVP-iodine) has a bactericidal effect and is effective against most bacteria, including putative periodontal pathogens. The aim of the present study was to evaluate the clinical effect of PVP-iodine as an adjunct to ultrasonic scaling in the treatment of severe chronic periodontitis.

MATERIAL AND METHODS

Twenty patients were recruited to the study. Each test site and the related quadrant were randomly assigned to one of four different treatment modalities: ultrasonic scaling + subgingival irrigation with 0.5% PVP-iodine for 5 min/tooth, ultrasonic scaling + subgingival irrigation with sterile saline solution for 5 min/tooth, subgingival irrigation with sterile saline solution for 5 min/tooth, and subgingival irrigation with 0.5% PVP-iodine for 5 min/tooth. The individuals were followed longitudinally for 6 months.

RESULTS

The present study showed that non-surgical periodontal therapy by means of an ultrasonic device was effective in attaining a healthy periodontal status in patients with severe periodontal lesions. No additive effect was found when PVP-iodine was included.

CONCLUSIONS

Ultrasonic debridement using Odontogain is effective in controlling infection in patients with severe chronic periodontitis. PVP-iodine does not add any clinical benefit to the ultrasonic debridement alone under these circumstances.

Povidone-Iodine Used as an Adjunct to Non-Surgical Treatment of Furcation Involvements

BACKGROUND

The aim of this clinical trial was to evaluate the effect of topically applied povidone-iodine (polyvinylpyrrolidone and iodine [PVP-I]) used as an adjunct to non-surgical therapy of furcation involvements.

METHODS

Forty-four patients presenting at least one Class II furcation involvement that bled on probing with probing depth (PD)>or=5 mm were recruited. Patients were stratified into two treatment groups: 1) subgingival instrumentation by an ultrasonic device using PVP-I (10%) as the cooling liquid (test); and 2) identical treatment using distilled water as the cooling liquid (control). The following clinical outcomes were evaluated: plaque index, bleeding on probing (BOP), position of the gingival margin, relative attachment level (RAL), PD, and relative horizontal attachment level (RHAL). The N-benzoyl-L-arginine-p-nitroanilide (BAPNA) test was used to analyze the trypsin-like activity in dental biofilm. The clinical and biochemical parameters were evaluated at baseline and 1, 3, and 6 months after therapy.

RESULTS

Both groups had similar means of PD reduction and RAL and RHAL gain. At 6 months, these variables were, respectively, 2.31, 1.17, and 1.00 mm in the control group and 2.31, 1.23, and 1.02 mm in the test group. There was also no difference between groups regarding the number of furcation sites presenting RAL gain>or=2 mm. The results of the BAPNA test failed to demonstrate significant differences between groups.

CONCLUSION

Non-surgical therapy can effectively treat Class II furcation involvements, and the use of topically applied PVP-I as an adjunct to subgingival instrumentation does not provide additional benefits.

A laboratory model biofilm fermenter: design and initial trial on a single species biofilm

BACKGROUND

The minimum inhibitory concentration (MIC) does not provide information on the efficacy of antimicrobial agents against infections involving biofilms, which are many times more resistant than planktonic forms of bacteria. This report is on the design and initial trial of a device for growing standard biofilms and testing antimicrobial agents.

METHODS

We constructed a durable, autoclaveable laboratory model biofilm fermenter (LMBF) that holds hydroxyapatite discs 300 microm below a surface onto which an artificial saliva medium drips at a rate comparable to human salivary flow. Inoculated with Streptococcus sanguinis, the device formed biofilms that were swept with a Teflon wiper under aerobic conditions. Five-day-old biofilm-coated discs were aseptically removed and placed in 3 ml of sterile saline, 0.12% chlorhexidine gluconate, or 0.1% phosphate-buffered chlorine dioxide mouthwash for 1 minute. The discs and test agent were immediately diluted with saline to 10 ml, vortexed for 30 seconds, serially diluted, plated on blood agar, and incubated anaerobically 2 days. Bacterial counts were done, and the MIC of each mouthwash was determined.

RESULTS

In tests with sterile water and sterile medium, the device maintained a closed system. After inoculation with S. sanguinis, a steady state was reached at day 5. Chlorhexidine at stock concentration achieved about a 2 log10 reduction (P = 0.002), but never achieved complete killing. Chlorine dioxide had no significant effect. The MIC against planktonic S. sanguinis was 112.8 microg/ml for chlorhexidine and 9.0 microg/ml for chlorine dioxide.

CONCLUSIONS

The LMBF generates and maintains a single-species oral model biofilm to a steady state and enables in vitro tests of disinfectant mouthwashes in simulated clinical use. It should be usable for more advanced tests of multiple species biofilms.

Povidone-iodine as a periodontal pocket disinfectant

OBJECTIVES AND BACKGROUND

Povidone-iodine [polyvinylpyrrolidone-iodine complex (PVP-iodine)] might constitute a valuable adjunct to current periodontal therapy because of its broad-spectrum antimicrobial activity, low potential for developing resistance and adverse reactions, wide availability, ease of use, and low financial cost. This investigation employed a randomized, split-mouth study design to determine the microbiological and clinical effects of 10% PVP-iodine subgingival irrigation in periodontitis lesions showing radiographic evidence of subgingival calculus.

METHODS

Sixteen adults having at least one periodontal pocket of 6 mm or more in each quadrant of the dentition and harboring one or more periodontopathic bacteria participated in the study. In each subject, a study site in each quadrant was randomly chosen to receive either subgingival irrigation with 10% PVP-iodine together with scaling and root planing, scaling and root planing alone, subgingival irrigation with 10% PVP-iodine, or subgingival irrigation with sterile saline. Prior to therapy and at 5 weeks post-treatment, microbiological culture was carried out without knowledge of the clinical status or the type of treatment rendered. A blinded clinical examiner determined presence of dental plaque, probing pocket depth, and gingival bleeding on probing. Microbiological and clinical data were analyzed using a repeated measures analysis of variance and Kruskal-Wallis rank test with the Tukey and Mann-Whitney post hoc tests.

RESULTS

At 5 weeks post-treatment, subgingival irrigation with PVP-iodine together with scaling and root planing caused a 95% or greater reduction in total pathogen counts in 44% of pockets having >/= 6 mm depth whereas scaling and root planing alone, povidone-iodine irrigation alone and water irrigation alone caused 95% reduction of total pathogens only in 6-13% of similar study sites (P = 0.02). Reduction in mean pocket depth was 1.8 mm for the PVP-iodine/scaling and root planing group, 1.6 mm for the scaling and root planing group, and 0.9 mm for the PVP-iodine and the saline monotherapy groups, with statistical significance reached for the scaling and root planing group vs. the PVP-iodine group (P = 0.04) and for the scaling and root planing group vs. the saline group (P = 0.02). Reduction in visible dental plaque, which ranged from 38% to 62%, showed no significant differences among treatment groups.

CONCLUSIONS

The addition of subgingival PVP-iodine irrigation to conventional mechanical therapy may be a cost-effective means of reducing total counts of periodontal pathogens and helping control periodontal disease. However, subgingival irrigation with PVP-iodine without concomitant mechanical debridement might not improve microbiological and clinical variables in comparison with saline irrigation, at least not in sites with radiographic evidence of subgingival calculus.

Initial effect of controlled release chlorhexidine on subgingival microorganisms

BACKGROUND

Little or no data exist on the ability of subgingival application of PerioChip (2.5 mg chlorhexidine gluconate in a biodegradable chip; Astra Pharmaceuticals, Westborough, MA, USA) to suppress periodontopathic microorganisms. The present study compared the subgingival microbiota of periodontitis sites receiving the chlorhexidine chip plus scaling and root planing (Sc/Rp) or Sc/Rp alone.

METHODS

Seven males and six females, mean age 49 years, with moderate to advanced periodontitis participated in the study. In each patient, two bilateral pockets probing 6-7 mm were randomly assigned to treatment by chlorhexidine chip + Sc/Rp, or by Sc/Rp alone. Subgingival placement of chlorhexidine chips was carried out according to the manufacturer's instructions. Sc/Rp was performed with hand instruments for at least 10 min in each study tooth. Subgingival samples were collected by paper-points at baseline, at 2 weeks and at 4 weeks post-treatment. Anaerobic culture methods were used for microbial isolation and identification. The microbiologic examination was carried out blindly. Microbiological data were evaluated by a repeated measures analysis of variance.

RESULTS

No statistical difference was found in total colony counts between subgingival sites treated with chlorhexidine chip + Sc/Rp and those treated with Sc/Rp alone. Also, the percentage of major periodontal pathogens (Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Bacteroides forsythus) and the percentage of total periodontal pathogens (A. actinomycetemcomitans, P. gingivalis, B. forsythus, Prevotella intermedia-group, Fusobacterium, Eubacterium, Campylobacter rectus, Peptostreptococcus micros, Eikenella corrodens, enteric rods) were not significantly different between the chlorhexidine chip + Sc/Rp group and the Sc/Rp group. At baseline, A. actinomycetemcomitans was recovered from 4 chlorhexidine chip + Sc/Rp sites and 2 Sc/Rp sites, P. gingivalis from 5 chlorhexidine chip + Sc/Rp sites and 4 Sc/Rp sites, and B. forsythus from 9 chlorhexidine chip + Sc/Rp and 7 Sc/Rp sites. At 4 weeks, A. actinomycetemcomitans was detected in 2 chlorhexidine chip + Sc/Rp sites but not in any site receiving Sc/Rp, P. gingivalis in 2 chlorhexidine chip + Sc/Rp sites but not in any Sc/Rp site, and B. forsythus in 1 chlorhexidine chip + Sc/Rp and in 2 Sc/Rp sites.

CONCLUSION

The present data obtained from bilateral periodontitis lesions of 13 adults suggest that chlorhexidine chip treatment of adult periodontitis lesions provides little or no additional antimicrobial benefits compared to thorough Sc/Rp alone.

Nonsurgical periodontal therapy

Regular home care by the patient in addition to professional removal of subgingival plaque is generally very effective in controlling most inflammatory periodontal diseases. When disease does recur, despite frequent recall, it can usually be attributed to lack of sufficient supragingival and subgingival plaque control or to other risk factors that influence host response, such as diabetes or smoking. Causative factors contributing to recurrent disease include deep inaccessible pockets, overhangs, poor crown margins and plaque-retentive calculus. In most cases, simply performing a thorough periodontal debridement under local anesthesia will stop disease progression and result in improvement in the clinical signs and symptoms of active disease. If however, clinical signs of disease activity persist following thorough mechanical therapy, such as increased pocket depths, loss of attachment and bleeding on probing, other pharmacotherapeutic therapies should be considered. Augmenting scaling and root planing or maintenance visits with adjunctive chemotherapeutic agents for controlling plaque and gingivitis could be as simple as placing the patient on an antimicrobial mouthrinse and/or toothpaste with agents such as fluorides, chlorhexidine or triclosan, to name a few. Since supragingival plaque reappears within hours or days after its removal, it is important that patients have access to effective alternative chemotherapeutic products that could help them achieve adequate supragingival plaque control. Recent studies, for example, have documented the positive effect of triclosan toothpaste on the long-term maintenance of both gingivitis and periodontitis patients. Daily irrigation with a powered irrigation device, with or without an antimicrobial agent, is also useful for decreasing the inflammation associated with gingivitis and periodontitis. Clinically significant changes in probing depths and attachment levels are not usually expected with irrigation alone. Recent reports, however, would indicate that, when daily irrigation with water was added to a regular oral hygiene home regimen, a significant reduction in probing depth, bleeding on probing and Gingival Index was observed. A significant reduction in cytokine levels (interleukin-1beta and prostaglandin E2, which are associated with destructive changes in inflamed tissues and bone resorption also occurs. If patient-applied antimicrobial therapy is insufficient in preventing, arresting, or reversing the disease progression, then professionally applied antimicrobial agents should be considered including sustained local drug delivery products. Other, more broadly based pharmacotherapeutic agents may be indicated for multiple failing sites. Such agents would include systemic antibiotics or host modulating drugs used in conjunction with periodontal debridement. More aggressive types of juvenile periodontitis or severe rapidly advancing adult periodontitis usually require a combination of surgical intervention in conjunction with systemic antibiotics and generally are not controlled with nonsurgical anti-infective therapy alone. It should be noted, however, that, to date, no home care products or devices currently available can completely control or eliminate the pathogenic plaques associated with periodontal diseases for extended periods of time. Daily home care and frequent recall are still paramount for long-term success. Nonsurgical therapy remains the cornerstone of periodontal treatment. Attention to detail, patient compliance and proper selection of adjunctive antimicrobial agents for sustained plaque control are important elements in achieving successful long-term results. Frequent re-evaluation and careful monitoring allows the practitioner the opportunity to intervene early in the disease state, to reverse or arrest the progression of periodontal disease with meticulous nonsurgical anti-infective therapy.

Molecular characterization of vancomycin-resistant Enterococci repopulating the gastrointestinal tract following treatment with a novel glycolipodepsipeptide, ramoplanin

We characterized baseline and repopulating stool isolates recovered during a phase II trial of ramoplanin for the treatment of patients with stool carriage of vancomycin-resistant enterococci (VRE). Repopulation with a strain with a related genotype was found in 74, 60, and 53% of individuals in groups treated with placebo, 100 mg of ramoplanin, and 400 mg of ramoplanin, respectively. All ramoplanin-treated patients with a culture positive for VRE at day 7 had a relapse caused by a genotypically related isolate. In ramoplanin-treated patients, antibiotics with activities against anaerobic organisms were associated with positive cultures on day 7 (relative risk [RR] = 8.8; P = 0.004), and the avoidance of such antibiotics was significantly associated with culture negativity through day 21 (RR = 0.16; P = 0.02).

The use of PVP-iodine as an adjunct to non-surgical treatment of chronic periodontitis

OBJECTIVE

The present study was performed to assess the effect of topically-applied PVP-iodine, used as an adjunct both during basic non-surgical therapy and at re-treatment during the long-term maintenance of patients with advanced periodontal disease.

MATERIAL AND METHODS

223 patients with advanced destructive periodontitis were recruited. The participants met the following inclusion criteria: (i) a minimum of 8 non-molar teeth, (ii) probing pocket depth of > or = 6 mm at > or = 2 teeth in each dentate quadrant, and radiographic bone loss exceeding 40% at the same teeth. A baseline I examination included assessment of plaque, gingivitis, probing pocket depth (PPD), probing attachment level (PAL) and radiographic bone height (RxBL). Following baseline I, the patients were stratified into 2 treatment groups; 2 subjects out of 3 were included in a control group and 1 in a test group. All participants, on an individual basis, received a case presentation and were instructed in proper self-performed plaque control measures. Non-surgical therapy was performed by the use of an ultrasonic device. The instrumentation in the test group was combined with the administration of 0.1% PVP-iodine. All subjects were recalled for comprehensive examinations 3, 6 and 12 months (baseline II) after baseline I and then after 3, 5 and 13 years of maintenance therapy. PAL determinations were performed annually. Subjects (losers) who at the re-examinations after 1, 2 and 3 years of maintenance demonstrated an annual further loss of PAL > or = 2 mm at > or = 4 teeth were exited from the study and referred for re-treatment. There were 9 losers in the test and 31 in the control group. In addition, 8 subjects in the test and 25 subjects in the control group withdrew from the trial for reasons unrelated to the study. These 73 subjects were not included in the data presentation from the various examinations.

RESULTS

It was demonstrated that non-surgical periodontal therapy resulted in (i) improved gingival conditions, (ii) reduced PPD, (iii) gain in PAL. It was also documented that the topical application of 0.1% PVP-iodine in conjunction with the mechanical root debridement established conditions which further improved the outcome of therapy. This was evidenced by the fact that at the 3, 6, and 12 months re-examinations after baseline I, the test group had significantly lower mean PPD values and significantly more gain of PAL than the control group. During the 12 years of SPT, it was possible for most subjects in both groups to maintain shallow pockets and to avoid marked further loss of PAL. There were, however, a larger number of losers in the control than in the test group.

CONCLUSION

PVP-iodine, topically applied during subgingival instrumentation, may improve the outcome of non-surgical periodontal therapy.

An in vitro evaluation of the antimicrobial efficacy of irrigants on biofilms of root canal isolates

AIM

The bactericidal effect of four antimicrobial agents was investigated against single-species biofilms derived from a range of root canal isolates.

METHODOLOGY

Single-species biofilms of Prevotella intermedia, Peptostreptococcus micros, Streptococcus intermedius, Fusobacterium nucleatum and Enterococcus faecalis were generated on membrane filter discs and subjected to 15 min or 1 h incubation with 5 p.p.m. colloidal silver, 2.25% sodium hypochlorite (NaOCl), 0.2% chlorhexidine, 10% iodine or phosphate buffered saline (PBS) as a control. The antimicrobial activity of the agents was neutralized and the bacterial cells were harvested from the discs by vortexing, serially diluted in reduced transport fluid, plated on fastidious anaerobe agar containing 5% horse blood, incubated anaerobically and colony-forming units calculated.

RESULTS

Iodine and NaOCl were more effective than chlorhexidine except against P. micros and P. intermedia where they were all 100% effective. Iodine and NaOCl elicited a 100% kill after 1 h incubation for all strains used. However, after 15 min, they showed differing bactericidal effects depending on the strain. None of the agents were effective against F. nucleatum after 15 min but NaOCl, iodine and chlorhexidine were all effective after 1 h. Colloidal silver was generally ineffective.

CONCLUSIONS

The effectiveness of a particular agent was dependent on the nature of the organism in the biofilm and on the contact time. NaOCl was generally the most effective agent tested, followed by iodine. However the clinical efficacy of these agents must be considered in light of the complex root canal anatomy and polymicrobial nature of root canal infections.

Nonsurgical periodontal therapy in 2000: a literature review

BACKGROUND

This article addresses the advantages and limitations of nonsurgical periodontal therapies to treat patients with mild-to-moderate chronic periodontitis.

TYPES OF STUDIES REVIEWED

Controlled clinical trials were selected that assessed the efficacy of the following treatment methods: mechanical instrumentation, ultrasonic débridement, supragingival irrigation, subgingival irrigation, local drug delivery, administration of systemic antibiotics and host-response modulation. Evidently, data with regard to alterations of probing depth, clinical attachment levels and inflammatory status were evaluated.

RESULTS

Comparison of the data from test and control groups revealed the following results. Manual and ultrasonic débridement can be used to treat most patients with mild-to-moderate chronic periodontitis. Patients who do not practice optimal plaque control can enhance their personal hygiene procedures by using supragingival irrigation. Subgingival irrigation usually does not provide any benefit beyond that achieved with root planing. Systemic and locally delivered antimicrobial agents appear to be most beneficial among patients who do not respond to conventional treatment. Host modulation may enhance root planing modestly.

CLINICAL IMPLICATIONS

The data indicate that most patients with mild-to-moderate periodontitis can be treated with nonsurgical therapies. However, clinicians need to be aware of the limitations of each technique with regard to the magnitude of improvement that it can induce at specific sites.

Povidone-iodine's effects and role in the management of periodontal diseases: a review

This review article addresses the effects of povidone-iodine (PVP-I) and its utility in the treatment of periodontal diseases. There are data to support the following statements: PVP-I is a potent antiseptic and, when used as a component in a rinse with H202, the rinse can decrease the level of gingivitis. With regards to patients with adult periodontitis, there is some evidence to indicate that PVP-I delivered via an ultrasonic device achieves better results in deep pockets than ultrasonic debridement when water is the irrigant. The benefits of PVP-I in the treatment of refractory periodontitis are unclear. Subgingival irrigation with PVP-I may reduce the incidence of bacteremia if it is employed as a pre-procedural intrasulcular irrigant; however, this technique is not recommended for high-risk patients. PVP-I is a safe antiseptic and does not appear to impede wound healing or induce resistant bacteria. It is an approved drug whose intraoral use is an unlabeled indication. In conclusion, the literature suggests that utilization of PVP-I is potentially beneficial in the management of some periodontal diseases. However, additional clinical trials are needed to verify this assessment, since it is based upon a limited number of studies.

The role of local drug delivery in the management of periodontal diseases: a comprehensive review

This review article evaluates the role of local drug delivery systems in the management of periodontal diseases. The efficacy of several local delivery devices (i.e., tetracycline fibers, metronidazole and minocycline gels, chlorhexidine chips, and doxycycline polymer) which are either commercially available in the United States or abroad, or are currently under consideration for Food and Drug Administration (FDA) approval are discussed. The drug delivery systems are assessed with regard to their functional characteristics, effectiveness as a monotherapy, as compared to scaling and root planing, and ability to enhance conventional therapy. Furthermore, controversies associated with local delivery are addressed (e.g., induction of bacterial resistant strains, the efficacy of systemic versus local drug delivery, and whether local drug delivery should function as an alternative or as an adjunct to conventional treatment).

Testing antimicrobial susceptibilities of adherent bacteria by a method that incorporates guidelines of the National Committee for Clinical Laboratory Standards

Membrane filters (0.22-microns pore size) were colonized with 10(4) CFU of logarithmic-phase bacteria per filter under laminar flow conditions in a Modified Robbins Device. Colonized filters were then placed upon agar dilution plates for MIC determinations. Subsequently, filters were transferred to control plates and incubated to obtain MBCs.

The effect of 3 mouthrinses on plaque and gingivitis development

The aim of this study was to evaluate the effect of 3 mouthrinses, Listerine Antiseptic (thymol), Peridex (chlorhexidine), Perimed (povidone iodine and hydrogen peroxide), and a placebo (water) on the development of dental plaque and gingivitis, when used as the only oral hygiene procedure for 14 days. 71 subjects were entered into a randomized, double-blind study. At the baseline examination, papillary bleeding score (PBS), and plaque index (PI) were registered, after which subjects received supragingival prophylaxis and were assigned to 1 of 4 study cells. Subjects were asked to refrain from all oral hygiene procedures except for the supervised 14-day 2 x daily rinsing with the assigned preparation. At day 14, the same clinical parameters were again registered. Statistical analysis was performed by a one-way analysis of variance (ANOVA) to compare the 4 groups, followed by Duncan's multiple range test to determine specific group differences. At baseline, average PBS and PI scores were similar for all 4 groups. After 14 days, the average PBS for Peridex and Perimed was significantly lower than for Listerine Antiseptic and water. The frequency of interdental units with a PBS greater than 2 was significantly lower for Peridex and Perimed than for Listerine Antiseptic and water. We concluded that both Peridex and Perimed were effective in reducing plaque and gingivitis when used as a 2 x daily mouthrinse by subjects refraining from other oral hygiene procedures. In vitro, a synergistic effect was assumed when inhibition was achieved with Perimed at the same or greater dilution than was achieved with povidone-iodine alone.

Susceptibility testing of anaerobic bacteria: myth, magic, or method?

The demand for susceptibility testing of anaerobes has increased, yet consensus as to procedure and interpretation in this area has not been achieved. While routine testing of anaerobic isolates is not needed, certain isolates in specific clinical settings should be tested. Also, laboratories may monitor their local antibiograms by doing periodic surveillance batch testing. The National Committee for Clinical Laboratory Standards has published a protocol of methods approved for susceptibility testing of anaerobic bacteria. Both agar and broth microdilution are included; however, the broth disk elution method is no longer approved by the National Committee for Clinical Laboratory Standards because of method-related interpretive errors. A number of newer methods are undergoing evaluation and seem promising. Clinicians and microbiologists reviewing susceptibility reports should be aware of sources of variability in the test results. Variables in susceptibility testing of anaerobes include the media and methods used, organisms chosen for testing, breakpoints chosen for interpretation, antibiotic, and determination of endpoint. Clustering of MICs around the breakpoint may lead to significant variability in test results. Adherence of testing laboratories to approved methods and careful descriptions of the method and the breakpoints used for interpretation would facilitate interlaboratory comparisons and allow problems of emerging resistance to be noted. A variety of resistance mechanisms occurs in anaerobic bacteria, including the production of beta-lactamase and other drug-inactivating enzymes, alteration of target proteins, and inability of the drug to penetrate the bacterial wall. Antimicrobial resistance patterns in the United States and abroad are described.

Inhibition of intergeneric coaggregation among oral bacteria by cetylpyridinium chloride, chlorhexidine digluconate and octenidine dihydrochloride

The potential inhibitory effect of chlorhexidine digluconate on the intergeneric coaggregation of 11 pairs of Gram-positive organisms was compared to its ability to inhibit coaggregations of 14 pairs comprised of both a Gram-positive and a Gram-negative cell type. Dramatic differences in the inhibitory effectiveness of the antimicrobial compound on the two kinds of coaggregation pairs were found. Gram-positive pairs were not inhibited at a concentration of 0.25%, whereas the coaggregations involving a Gram-negative partner were usually completely blocked at concentrations as low as 0.01%. Similar effects to chlorhexidine digluconate were found with octenidine dihydrochloride and cetylpyridinium chloride, while sodium dodecylsulfate was inhibitory only at 10- to 50-fold higher concentrations. These results suggest that chlorhexidine digluconate, octenidine dihydrochloride, and cetylpyridinium chloride may be effective inhibitors of later microbial colonizers of dental plaque but may not disturb a normal healthy indigenous flora.

Effect of antiseptic mouthwashes on some clinical and microbiological findings in the mouths of lymphoma patients receiving cytostatic drugs

51 patients suffering from Hodgkin's disease or non-Hodgkin's lymphoma participated in this double-blind, cross-over study in which 2 antiseptic mouthwashes were tested for their effects on various periodontal index scores and salivary microbial counts. All patients were receiving combination cytostatic treatment based on methotrexate and doxorubicin. The patients (49 +/- 14 years old, 28 men, 23 women) were allotted at random to 2 groups. One rinsed with a 0.12% chlorhexidine gluconate (CHX) solution, the other with a 0.025% amine-stannous fluoride (AmF + SnF) solution 2x daily for 2 weeks. Both groups then continued rinsing with a 0.05% sodium fluoride (F) solution for 2 weeks, before switching over to AmF + SnF or CHX, respectively. All solutions had been prepared in such a way that they had the same colour and taste. Visible plaque index and gingival bleeding index scores were significantly reduced after periods of rinsing with CHX solution (P less than 0.001) and AmF + SnF solution (P less than 0.05). Microbiological cultivations of saliva specimens revealed significant reductions in mutans streptococci immediately after commencing rinsing, while lactobacilli and yeast counts were not affected.

Short-term bactericidal activity of chlorhexidine gel, stannous fluoride gel and amine fluoride gel tested in periodontal pockets

The short-term bactericidal effect of 2% chlorhexidine gel, 4% stannous fluoride gel or amine fluoride gel containing 1.25% fluoride on the subgingival microflora was determined in 40 periodontal pockets of 10 patients. The antimicrobial gels or placebo gel were applied in 5-9 mm deep periodontal pockets 3 times within 10 min. Before and 30 min after the applications, samples were taken of the subgingival microflora for determination of the total number of bacteria as well as the number of black pigmented Bacteroides. Reductions of the total number of bacteria were found in all test groups. The reductions found in the pockets treated with chlorhexidine gel or stannous fluoride gel were significantly greater than the reduction found in the pockets treated with a placebo gel. A significant reduction of black-pigmented Bacteroides was found after treatment with chlorhexidine gel or amine fluoride gel. It is concluded that 2% chlorhexidine gel or 4% stannous fluoride gel has a more than 99% reduction effect on the microflora of periodontal pockets within 30 min after application.

In vitro susceptibility of mutans streptococci to antimicrobial substances as determined by a membrane transfer assay

The in vitro susceptibilities of seven representative strains of mutans streptococci to three topically applied chemotherapeutic agents were determined by a modified membrane transfer assay. The MBCs of chlorhexidine and I2-KI ranged from 0.5 to 1.0%, while SnF2 was sublethal at the highest concentration tested (8%) in all but one strain (AHT; mode MBC, 8.0%). The proposed in vitro assay may be useful for preclinical screening of potential antimicrobial agents prior to use in the oral cavity.

Activity of amine-stannous fluoride combination and chlorhexidine against some aerobic and anaerobic oral bacteria

The in vitro susceptibility of 128 bacterial strains was tested to amine fluoride-stannous fluoride (AmF + SnF) and chlorhexidine (CHX) solutions. Actinobacillus actinomycetemcomitans, Streptococcus mutans, and Bacteroides intermedius were among the species investigated. The 50% and 90% minimal inhibitory concentrations (MICs) were assessed by an agar dilution method. The MIC ranges for A. actinomycetemcomitans were 2-32 micrograms/ml for CHX and 0.25-64 micrograms/ml for AmF + SnF. The respective values for S. mutans were 0.5-8 micrograms/ml (CHX) and 2-8 micrograms/ml (AmF + SnF); and 4-8 micrograms/ml (CHX) and 2-4 micrograms/ml (AmF + SnF) for B. intermedius. Streptococcus faecalis and Staphylococcus aureus were most resistant of the control strains (MIC 64 micrograms/ml to CHX and 32 micrograms/ml to AmF + SnF, respectively). Thus, both solutions tested exerted a definite inhibitory action on the dental plaque pathogens studied.

Bactericidal concentrations of chlorhexidine-digluconate, amine fluoride gel and stannous fluoride gel for subgingival bacteria tested in serum at short contact times

In vitro inhibitory and bactericidal concentrations in serum of chlorhexidine-digluconate, amine fluoride gel, stannous fluoride gel, stannous fluoride, metronidazole and amoxicillin were determined against Bacteroides gingivalis, Bacteroides intermedius, Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans and Capnocytophaga sputigena. The minimal inhibitory concentration was assessed by the agar dilution technique. The killing curves and minimal bactericidal concentration of the antimicrobial agents in inactivated bovine serum were determined after 5, 10, 20 and 60 minutes contact time. The minimal inhibitory concentration varied amongst the tested bacteria. A concentration of 128 micrograms/ml chlorhexidine digluconate, 20 mg/ml amine fluoride gel, 1 mg/ml stannous fluoride, 128 micrograms/ml metronidazole and 4 micrograms/ml amoxicillin inhibited the growth of the tested species. The minimal bactericidal concentration in serum for B. gingivalis, B. intermedius, F. nucleatum, A. actinomycetemcomitans and C. sputigena after 10 min contact time was 5 mg/ml for chlorhexidine digluconate and 100 mg/ml for amine fluoride gel. A concentration of 200 mg/ml stannous fluoride gel in serum was bactericidal for the tested species after 10 min contact time, with exception of F. nucleatum.

Microbiological effects of mouthrinses containing antimicrobials

A number of mouthrinse formulations containing antimicrobials have been evaluated to determine their effectiveness as antiplaque and/or antigingivitis agents. These have included the bis-biguanides, phenols, quaternary ammonium compounds, oxygenating compounds, plant extracts, fluorides, antibiotics and antimicrobial combinations. These mouthrinses have often been tested as adjuncts to normal oral hygiene procedures as well as in the experimental gingivitis model. 2 agents in particularly, chlorhexidine gluconate and listerine, have been shown to both inhibit or reduce plaque accumulation and the severity of gingivitis. Chlorhexidine has been reported to reduce the accumulation of plaque by approximately 60% and the severity of gingivitis by 50-80% as determined by improvements in clinical indices. A 0.12% chlorhexidine gluconate rinse resulted in significant reductions after both 3 and 6 months use in the numbers of total anaerobes, total aerobes, streptococci, and actinomyces recovered from supragingival plaque. Listerine has been reported to retard the development of plaque by 45 to 56% and to reduce existing plaque by 39 to 48%. Gingivitis scores were reduced as much as 59%. Microbial studies have shown that the effect of listerine is exerted against the total microbial mass and results in an overall decrease in both the biomass and the activity. Long-term use of neither mouthrinse, chlorhexidine or listerine, resulted in the emergence of opportunistic or oral pathogens. Preliminary data obtained following the use of a novel mouthrinse consisting of a combination of povidone-iodine and hydrogen peroxide appears promising. This combination was more effective than was more effective than either single component alone in reducing gingivitis scores.(ABSTRACT TRUNCATED AT 250 WORDS)