3 regimens of topical metronidazole compared with subgingival scaling on periodontal pathology in adults

Specific delivery of metronidazole using microparticles and thermosensitive in situ hydrogel for intrapocket administration as an alternative in periodontitis treatment

Periodontitis is a common chronic inflammatory disease primarily caused by the prevalence of bacterial overgrowth resulting in the development of an inflammatory condition that destroys the tooth's supporting tissues and eventual tooth loss. Comparatively, to other treatment methods, it is difficult for topical antibacterial drugs to effectively permeate the biofilm's physical barrier, making conventional therapy for periodontitis more challenging. This novel study combines thermosensitive in situ hydrogel with microparticles (MPs) to enhance the targeted delivery of metronidazole (MET) to the periodontal pocket. Polycaprolactone (PCL) polymer was utilized to produce bacteria-sensitive MPs. Additionally, the study assessed the attributes of MPs and demonstrated an enhancement in the in vitro antibacterial efficacy of MPs towards Staphylococcus aureus (SA) and Escherichia coli (EC). Subsequently, we incorporated MET-MPs into thermosensitive in situ hydrogel formulations using chitosan. The optimized formulations exhibited stability, appropriate gelation temperature, mucoadhesive strength, and viscosity. In vitro permeation tests showed selective and prolonged drug release against SA and EC. Ex vivo experiments demonstrated no significant differences between in situ hydrogel containing pure MET and MET-MPs in biofilm quantity, bacterial counts, and metabolic activity in biofilms. According to in vitro tests and the effectiveness of the antibacterial activity, this study has exhibited a novel methodology for more efficacious therapies for periodontitis. This study aims to utilize MET in MPs to improve its effectiveness, enhance its antibacterial activity, and improve patient treatment outcomes. In further research, the efficacy of the treatment should be investigated in vivo using an appropriate animal model.

The effect of antibiotics on the periodontal treatment of diabetic patients with periodontitis: A systematic review and meta-analysis

Background: The aim of this meta-analysis was to compare the effects of periodontal treatment with or without adjunctive antibiotic on periodontal status and blood glucose level in diabetic patients with periodontitis. Methods: A search using electronic database (MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials) and a manual search were performed up to July 2022. Eligible 13 RCTs were included according to inclusion and exclusion criteria. Reviewers independently performed data screening, data selection, data extraction, and risk of bias. Quality assessment was performed according to the Cochrane Handbook for Systematic Reviews of Interventions. Weighted mean differences and 95% confidence intervals (CIs) for continuous outcomes were calculated using random or fixed-effects models. This review is registered in the PROSPERO database (CRD42022347803). Results: Of the 13 included articles, eight were on the use of systemic antibiotics and five on topical antibiotics. The results showed statistically significant improvement in periodontal status (probing depth, clinical attachment loss and bleeding on probing) at 6 months with systematic antibiotics use (PD-6M p = 0.04, BOP-6M p < 0.0001, CAL-6M p = 0.002). The improvement in PD with topical antibiotics was statistically significant at 1 month (p = 0.0006). However, there was no statistically significant improvement in periodontal status at 3 months with adjuvant systemic antibiotics. Conclusion: Antibiotics can improve the periodontal condition of diabetic patients with periodontitis to a certain extent. In clinical practice, it is necessary to comprehensively consider the balance of benefits and risks before deciding whether to use antibiotics. Systematic Review Registration: Identifier CRD42022347803, https://www.crd.york.ac.uk/PROSPERO/.

Clinical effect of locally delivered gel containing green tea extract as an adjunct to non-surgical periodontal treatment

Green tea catechins had an in vitro antibacterial effect against periodontopathic bacteria and were able to inhibit destruction of the periodontal tissue. In this study, we aimed to evaluate the effect of locally delivered gel containing green tea extract as an adjunct to non-surgical periodontal treatment. Forty-eight subjects who had teeth with probing pocket depth of 5-10 mm were randomly allocated into the test or control group. Probing pocket depth, clinical attachment level, gingival index (GI), bleeding on probing (BOP) and full mouth plaque score were measured at baseline. Subjects received oral hygiene instruction, single episode of scaling and root planing and subgingival application of the green tea gel (test group) or the placebo gel (control group). The gel was repeatedly applied at 1 and 2 weeks later. The parameters were recorded again at the 1st, 3rd and 6th month after the last gel application. The results showed that all parameters were improved in both groups compared to baseline. The test group exhibited significantly higher reduction in BOP at the 3rd month (p = 0.003) and significantly lower GI at the 1st month (p < 0.001) and 3rd month (p < 0.001) when compared with the control group. Thus, green tea gel could provide a superior benefit in reducing bleeding on probing and gingival inflammation when used as an adjunct to non-surgical periodontal treatment. (

TRIAL REGISTRATION

MU-IRB 2008/153.0511, ClinicalTrials.gov NCT00918060).

Comparative evaluation of locally delivered minocycline and metronidazole in the treatment of periodontitis

Objective:

The aim of this study was to evaluate and compare the efficacy of subgingivally delivered Minocycline microspheres and 25% Metronidazole gel when used as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis.

Materials and Methods:

A randomized, controlled, single center study was conducted involving 60 sites in 20 patients suffering from moderate to advanced chronic periodontitis. Each patient contributed three sites which were randomized to three treatment groups: SRP + insertion of Minocycline microspheres at day 1 (Group A), SRP + insertion of Metronidazole gel at day 1 and at day 7 (Group B), and SRP alone (Group C). Gingival index (GI), plaque index (PI), probing pocket depth (PPD), and clinical attachment level (CAL) were recorded at day 1, 1 month, and 3 months post therapy.

Results:

All treatments showed significant reductions in PPD and CAL at 1 and 3 months when compared to baseline values (P < 0.001). At 3 months, sites treated with minocycline showed an additional reduction in PPD of 0.85 ± 0.03 mm, significantly greater than SRP alone. Differences in mean PPD reduction between Group B and Group C and between Group A and Group B were not significant. At 3 months, difference in CAL gain between Group A and C was 0.50 ± 0.45, which was statistically significant and between Group B and C was 0.35 ± 0.11, which was not found to be statistically significant (P = 0.20). Differences in relative CAL between Group A and Group B were also not found to be statistically significant (P = 0.53).

Conclusion:

The results concluded that treatment with Minocycline microspheres and Metronidazole gel improve PPD and CAL in patients with periodontitis compared to SRP alone.

Effect of local drug delivery in chronic periodontitis patients: A meta-analysis

Periodontal diseases are multi-factorial in etiology, and bacteria are one among these etiologic agents. Thus, an essential component of therapy is to eliminate or control these pathogens. This has been traditionally accomplished through mechanical means (scaling and root planing (SRP)), which is time-consuming, difficult, and, sometimes, ineffective. From about the past 30 years, locally delivered, anti-infective pharmacological agents, most recently employing sustained-release vehicles, have been introduced to achieve this goal. This systematic review is an effort to determine the efficacy of the currently available anti-infective agents, with and without concurrent SRP, in controlling chronic periodontitis. Four studies were included, which were all randomized controlled trials, incorporating a total patient population of 80, with 97 control sites and 111 test sites. A meta-analysis completed on these four studies including SRP and local sustained-release agents compared with SRP alone indicated significant adjunctive probing depth (PD) reduction for 10% Doxycycline hycylate (ATRIDOX), minocycline hydrochloride (ARESTIN), tetracycline hydrochloride (PERIODONTAL PLUS AB), and chlorhexidine gluconate (PERIOCHIP). Essentially, all studies reported substantial reductions in gingival inflammation, plaque scores, and bleeding indices, which were similar in both the control and the experimental groups. Use of antimicrobial sustained-release systems as an adjunct to SRP does not result in significant patient-centered adverse events. Local drug delivery combined with SRP appears to provide additional benefits in PD reduction compared with SRP alone.

Conventional endodontic treatment of primary molars using metronidazole as an intra-canal medicament: a pilot study

AIM

This was to evaluate the clinical and radiographic outcomes of an antibacterial drug (Metronidazole, Nidazol, IE Ulagay Ilac A.S) application as an intra-canal medicament combined with pulpectomy in infected primary molar teeth.

METHODS

The study material consisted of data collected from children treated at the Dental School Dept. of Paediatric Dentistry in Marmara University between 2000 and 2004. Clinical and radiographic data were collected over 2 years from patients who had received a topical application of metronidazole in root canal dressing before a pulpectomy was completed. Clinical success parameters were: no abscess formation, no fistula, no pain and no pathologic mobility at treated teeth with metranidazole dressing. The overall success and failure rates were analysed. Radiographic diagnosis was standardized between investigators and intra and inter-rater reliability assessed. Both investigators read and evaluated all radiographs, after a comparison of results, a consensus was agreed upon for each result.

STATISTICS

All data were entered into an Excel format and SPSS 11.0 P < 0.05 were used for Windows and Chi-square for statistical analyses.

RESULTS

There were 64 molars assessed for clinical and radiographic success. Considering the eruption times, success rate was 75% as determined by the last follow up clinically and radiographically according to predetermined success criteria. In the 64 molars, 4 cases demonstrated loss of the alveolar bone, 3 exhibited varying degrees of root resorptions on radiographic examination and 3 showed clinical pathologic mobility. Fistulae were observed in only 1 case and early loss was detected in 5 cases.

CONCLUSION

These results suggest that main factors responsible for failure may be associated with uncertain mixing proportions of the metronidazole paste and inadequate maxillary restorations. But some modifications in preparing the paste could increase its efficacy.

Evaluation of two local drug delivery systems as adjuncts to mechanotherapy as compared to mechanotherapy alone in management of chronic periodontitis: A clinical, microbiological, and molecular study

BACKGROUND

Modern concepts of treating inflammatory periodontal disease aim at changes in the subgingival ecosystems within the periodontal pockets to alter the complex microbial community into a microbiota compatible with good periodontal health. Systemic antimicrobial therapy, although effective, involves a relatively high dose with repeated intakes over a prolonged period of time to achieve the required inhibitory concentrations in the sulcular fluid. The adjunctive use of local drug delivery may provide a beneficial response, especially in specific areas where conventional forms of therapy might fail. The aim of this study was to compare the efficacy of two local drug delivery systems, one containing metronidazole and the other containing tetracycline hydrochloride as adjuncts to mechanotherapy in the treatment of chronic periodontitis.

MATERIALS AND METHODS

There were three groups that were labeled as group A (Scaling + Tetracycline), group B (Scaling + Metronidazole), and group C (Scaling alone). A microbiological analysis was carried out to determine the efficacy of these systems in changing the pathogenic flora in deep pockets. In addition, a multiplex polymerase chain reaction was carried out to confirm the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis (Pg), and Tannerella forsythensis in the flora associated with chronic periodontitis.

RESULTS

There was clinical improvement in groups A and B, which correlated with an improvement in the microbiological parameters; these results were sustained for 90 days following therapy. In Group C, the flora showed a shift towards baseline at the end of 90 days.

CONCLUSIONS

According to this study, both the local antibiotic therapies resulted in greater improvement in microbiological parameters when used as an adjunct to mechanotherapy as compared to mechanotherapy alone.

Application of chitosan gel in the treatment of chronic periodontitis

Local administration of antibiotics in periodontal therapy can be provided with an appropriate delivery system. The purpose of this study was to evaluate the clinical effectiveness of chitosan, both as a carrier in gel form and as an active agent in the treatment of chronic periodontitis (CP). The chitosan gel (1% w/w) incorporated with or without 15% metronidazole was prepared and applied adjunctive to scaling and root planing (SRP) in comparison to SRP alone (control group-C), in CP patients. The clinical parameters such as probing depth (PD), clinical attachment level, the amount of gingival recession, plaque index, gingival index, and gingival bleeding time index were recorded at baseline and at weeks 6, 12, and 24. In all groups, significant improvements were observed in clinical parameters between baseline and week 24 (p < 0.05). The reductions in PD values were 1.21 mm for Ch, 1.48 mm for Ch + M, and 0.94 mm for C groups. No complications related to the chitosan were observed in patients throughout the study period. It is suggested that chitosan itself is effective as well as its combination with metronidazole in CP treatment due to its antimicrobial properties.

Local Drug Delivery in the Treatment of Periodontal Diseases: Assessing the Clinical Significance of the Results

BACKGROUND

Local drug delivery can be used in the management of periodontal patients. However, statistically significant responses to therapy recorded in clinical trials may not be clinically significant.

METHODS

Controlled clinical trials were selected that assessed the capability of local drug delivery to improve periodontal health.

RESULTS

Several local drug delivery systems employed as monotherapies improved periodontal health and provided results that were not statistically significantly different than attained with scaling and root planing (SRP) alone. In contrast, many local drug delivery devices when used as adjuncts to SRP provided a statistically significant enhancement of parameters commonly used to monitor periodontal status. However, mean improvements with respect to probing depth reduction or gain of clinical attachment were often limited to tenths of millimeters. Several devices also achieved specific criteria that can be used to identify clinically significant findings (e.g., number of sites with probing depth reduction >or=2 mm). However, there are conflicting data with respect to the ability of local drug delivery to enhance results of SRP at deep probing sites, and there is limited information relative to its capability to inhibit disease progression or enhance osseous repair in infrabony defects.

CONCLUSION

The decision to use local drug delivery during active treatment or maintenance should be based upon clinical findings, responses to therapy recorded in the literature, desired clinical outcomes, and the patient's dental and medical history.

Local anti-infective therapy: pharmacological agents. A systematic review

BACKGROUND

It is well recognized that periodontal diseases are bacterial in nature. An essential component of therapy is to eliminate or control these pathogens. This has been traditionally accomplished through mechanical means (scaling and root planing [SRP]), which is time-consuming, difficult, and sometimes ineffective. Over the past 20 years, locally delivered, anti-infective pharmacological agents, most recently employing sustained-release vehicles, have been introduced to achieve this goal.

RATIONALE

This systematic review evaluates literature-based evidence in an effort to determine the efficacy of currently available anti-infective agents, with and without concurrent SRP, in controlling chronic periodontitis.

FOCUSED QUESTION

In patients with chronic periodontitis, what is the effect of local controlled-release anti-infective drug therapy with or without SRP compared to SRP alone on changes in clinical, patient-centered, and adverse outcomes?

SEARCH PROTOCOL

MEDLINE, the Cochrane Central Trials Register, and Web of Science were searched. Hand searches were performed of the Journal of Clinical Periodontology, Journal of Periodontology, and Journal of Periodontal Research. Searches were performed for articles published through April 2002. In addition, investigators contacted editors of the above-mentioned journals and companies sponsoring research on these agents for related unpublished data and studies in progress.

SELECTION CRITERIA

INCLUSION CRITERIA

Studies included randomized controlled clinical trials (RCT), and case-controlled and cohort studies at least 3 months long. Therapeutic interventions had to include 1) SRP alone; 2) local anti-infective drug therapy and SRP; or 3) local anti-infective drug therapy alone. Included studies had to report patient-based mean values and measures of variation for probing depth (PD) and/or clinical attachment levels (CAL) for both test and control groups.

EXCLUSION CRITERIA

Studies were excluded if they: 1) included data from a previously published article; 2) included daily rinsing with chlorhexidine (CHX); or 3) had unclear descriptions of randomization procedures, examiner masking, or concomitant therapies.

DATA COLLECTION AND ANALYSIS

For the meta-analysis, PD and CAL were expressed as summary mean effects with 95% confidence intervals (CI) for the effect, and analyzed using a standardized difference between SRP alone and experimental agent groups. The results were assessed with both fixed-effects and random-effects models. Studies were ranked according to the York system.

MAIN RESULTS

1. Thirty-two studies were included (28 RCT, 2 cohort, and 2 case-control), incorporating a total patient population of 3,705 subjects. 2. Essentially all studies reported substantial reductions in gingival inflammation and bleeding indices, which were similar in both control and experimental groups. 3. A meta-analysis completed on 19 studies that included SRP and local sustained-release agents compared with SRP alone indicated significant adjunctive PD reduction or CAL gain for minocycline (MINO) gel, microencapsulated MINO, CHX chip and doxycycline (DOXY) gel during SRP compared to SRP alone. 4. Use of antimicrobial irrigants or anti-infective sustained-release systems as an adjunct to SRP does not result in significant patient-centered adverse events.

REVIEWERS' CONCLUSIONS

1. In some populations, anti-infective agents in a sustained-release vehicle alone can reduce PD and bleeding on probing (BOP) equivalent to that achieved by SRP alone. 2. No evidence was found for an adjunctive effect on reduction of PD and BOP of therapist-delivered CHX irrigation during SRP compared to SRP alone. 3. Additional RCTs are needed which evaluate the effectiveness of these therapies in all forms of periodontitis. 4. The study protocol for future RCTs should include appropriate statistical analyses and complete data sets to facilitate future evidence-based reviews. 5. Alternative surrogate parameters to PD and CAL need to be identified and validated such as microbial, inflammatory, or tissue-destructive markers that could be used in conjunction with clinical parameters to help determine the patient's response to emerging technologies that target the infectious and/or inflammatory aspects of periodontitis. 6. Future Phase IV clinical trials should be designed that evaluate local anti-infective therapies in conjunction with SRP in a manner consistent with current standards of care and evaluate cost-effectiveness. 7. The use of local anti-infective agents in at-risk patient populations and for the treatment of at-risk disease sites needs to be validated in randomized controlled clinical trials. 8. Several local anti-infective agents combined with SRP appear to provide additional benefits in PD reduction and CAL gain compared to SRP alone. The decision to use local anti-infective adjunctive therapy remains a matter of individual clinical judgment, the phase of treatment, and the patient's status and preferences.

Locally delivered antimicrobials for the treatment of chronic periodontitis

The basic treatment of chronic periodontitis is a mechanical debridement of periodontal pockets by scaling and root planing (S/RP) in combination with efficient plaque control. Locally delivered antiseptics (LDA) have been proposed to practitioners and, while subgingival irrigation of antiseptics is still used in clinical practice, the introduction in our therapy of a slow release and sub-gingival delivery of tetracycline has changed the rationale from a mechanical treatment towards a combined therapy for full mouth/sites disinfection. Various antibiotics, antiseptics and resorbable carriers are now proposed with similar targets to arrest disease progression. In chronic periodontitis, LDA cannot be used routinely in combination with S/RP, because of the limited clinical benefit, even if an increased percentage of deep sites may show an improvement. Prospective multicenter studies considering risk factors for disease progression have to be designed to identify patients who may benefit the most from LDA. For non-responding sites or recurrent pockets, the controversies are limited, because a combined S/RP and LDA may avoid the need for surgery. However, the patient cost/benefit ratio needs to be estimated as well as adverse effects in particular antibiotics.

Clinical outcome observed in subjects with recurrent periodontal disease following local treatment with 25% metronidazole gel

BACKGROUND

The aim of this study was to evaluate the clinical outcome in patients with recurrent periodontal disease following treatment with 25% metronidazole gel.

METHODS

Twenty subjects in a maintenance care program but with recurrent periodontal disease participated. Three months after scaling and root planing, a total of 40 sites, 2 in each patient, with probing depth > or = 5 mm were selected. One site randomly selected was treated with metronidazole gel (test) and the other site with a placebo gel (control). Baseline and follow-up measurements included plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), and clinical attachment level (CAL).

RESULTS

There were no statistically significant differences in PI, GI, BOP, PD, or CAL between test and control sites.

CONCLUSION

This study showed that local treatment with 25% metronidazole gel did not seem to influence the clinical healing in this group of subjects with recurrent periodontal disease.

Meta-analysis of the effect of scaling and root planing, surgical treatment and antibiotic therapies on periodontal probing depth and attachment loss

OBJECTIVE

This paper reports a meta-analysis of studies that have investigated the effect of scaling and root planing on periodontal probing depth and attachment loss.

MATERIAL AND METHODS

The criteria used for inclusion of studies were as follows: root planing and scaling alone was one of the primary treatment arms; patients or quadrants of each patient were randomly assigned to study groups; 80% of patients enrolled were included in first year follow-up examinations; periodontal probing depth and attachment loss were reported in mm; the sample size of each study and substudy was reported. Sample size was used to weight the relative contribution of each study since standard errors were not reported by many studies and sample size is highly correlated with standard error and therefore statistically able to explain a substantial portion of the standard error on studies that use similar measures.

RESULTS

The meta-analysis results show that periodontal probing depth and gain of attachment level do not improve significantly following root planing and scaling for patients with shallow initial periodontal probing depths. However, there was about a 1-mm reduction for medium initial periodontal probing depths and a 2-mm reduction for deep initial periodontal probing depths. Similarly, there was about a 0.50-mm gain in attachment for medium initial periodontal probing depth measurements and slightly more than a l-mm gain in attachment for deep initial periodontal probing depth measurements. Surgical therapy for patients with deep initial probing depths showed better results than scaling and root planing in reducing probing depths. When patients were followed up over 3 years or more, these differences were reduced to less than 0.4 mm. Antibiotic therapy showed similar results to scaling and root planing. However, a consistent improvement in periodontal probing depth and gain of attachment is demonstrated when local antibiotic therapy is combined with root planing and scaling.

Clinical significance of non-surgical periodontal therapy: an evidence-based perspective of scaling and root planing

Analysis of Egyptian hieroglyphics and medical papyri indicate that non-surgical periodontal treatment was common 3000-4000 years ago. Even today, scaling and root planing (SRP) remains an essential part of successful periodontal therapy. The collective evidence from numerous clinical trials reveals a consistency of clinical response in the treatment of chronic periodontitis by SRP using manual, sonic, or ultrasonic instrumentation. Thus, SRP remains the 'gold standard' to which more recently developed therapeutic modalities must be compared. Inherent to the clinical evaluation of SRP are such concerns as manual versus sonic and ultrasonic instrumentation, control of sub-gingival bacterial populations, removal of calculus, root smoothness and changes in various clinical parameters, e.g. probing depth, attachment levels, bleeding on probing and gingival inflammation. Lastly, an abbreviated discussion is presented on a relatively new paradigm of complete mouth 'disinfection' in a compressed time-frame that includes SRP as a significant component of the treatment regimen.

Periodontal therapy using local delivery of antimicrobial agents

Antimicrobial agents, systemic and/or local, are thought by some to be effective agents for treating periodontal infections. Here the authors determine the costs and benefits of local delivery agents for treating periodontal disease. Applying this cost-benefit analysis to patient care, however, will depend upon a clinician's expertise and a patient's value system.

Local antimicrobial therapy after initial periodontal treatment

AIM

The aim of this single-blind, randomized, parallel-designed clinical trial (RCT) was to evaluate the clinical and microbiological effects of three sustained-release biodegradable polymers delivered into periodontal pockets following initial periodontal therapy.

METHODS

Forty-seven patients (28 females and 19 males) with a mean age of 51 years (range 29-71) underwent a periodontal examination at baseline (i.e. Week 0) and after 18 weeks. This included the assessment of the Plaque Index (PlI), Bleeding on Probing (BOP), Pocket Probing Depths (PPD) and Probing Attachment Levels (PAL) at six sites per tooth. Two to 4 months prior to baseline, all subjects had received initial periodontal therapy including motivation, instruction in oral hygiene practices and full-mouth scaling and root planing. At the treatment appointment (i.e. Week 2), the patients were randomly assigned to receive either Atridox trade mark, Elyzol Dental Gel or PerioChip at all residual periodontal pockets with a probing depth >/= 5 mm and concomitant BOP. In accordance with the manufacturer's recommendations, Elyzol Dental Gel was applied for a second time 7 days later. In addition to the clinical evaluation, subgingival microbiological samples were collected prior to treatment (i.e. Week 2) and at Weeks 4 and 18. Analysis of variance/covariance was used to evaluate changes from baseline to Week 18 for the clinical parameters.

RESULTS

Between the baseline and 18-week examinations, subjects treated with Atridox showed a significantly greater gain in mean PAL of 0.33 mm +/- 0.09 (SD) than subjects treated with Elyzol Dental Gel [0.03 mm +/- 0.09 (SD)](p = 0.03). However, the gain in PAL of 0.16 mm +/- 0.10 (SD) found after PerioChip application did not differ significantly from that obtained following the application of Atridox(p = 0.27). Of the sites treated with Atridox, 42% gained >/= 1 mm PAL and 9% >/= 2 mm PAL as opposed to the sites treated with Elyzol Dental Gel, in which 34% gained >/= 1 mm PAL and 8% gained >/= 2 mm PAL. Of the sites treated with PerioChip, 36% gained >/= 1 mm and 6% gained >/= 2 mm PAL following a completed initial periodontal therapy.

CONCLUSIONS

The application of the three biodegradable sustained release devices tested following initial periodontal therapy resulted in a statistically significant gain in mean PAL for AtridoxTM and a significant reduction in PPD for all three devices during the study period. Furthermore, when sites treated with Atridox were compared with sites treated with Elyzol, a significant difference in mean PAL gain (0.3 mm) was observed.

Sustained release of silver from periodontal wafers for treatment of periodontitis

Periodontal wafers intended to treat the underlying infections in patients with periodontitis have been developed. The wafers consist of poly(lactic-co-glycolic acid) as a primary bioerodible polymeric component, poly(ethylene glycol) as a plasticizer and encapsulation aid, and silver nitrate as the antimicrobial agent. The wafers are capable of sustained in vitro release of bioactive silver for at least 4 weeks. The wafers exhibit silver release that follows erosion kinetics, confirming a bulk erosion/release mechanism. In clinical evaluation, sustained release of silver at bactericidal levels for at least 21 days is observed. Staining of hard and soft tissues due to the released silver is minimal and reversible.

Controlled and targeted drug delivery strategies towards intraperiodontal pocket diseases

Advances in the understanding of the aetiology, epidemiology, pathogenesis and microbiology of periodontal pocket flora have revolutionized the strategies for the management of intraperiodontal pocket diseases. Intra-pocket, sustained release, drug delivery devices have been shown to be clinically effective in the treatment of periodontal infections. Several degradable and non-degradable devices are under investigation for the delivery of antimicrobial agents into the periodontal pocket including non-biodegradable fibres, films (biodegradable and non-biodegradable), bio-absorbable dental materials, biodegradable gels/ointments, injectables and microcapsules. With the realization that pocket bacteria accumulate as biofilms, studies are now being directed towards eliminating/killing biofilm concentrations rather than their planktonic (fluid phase) counterparts. Intraperiodontal pocket drug delivery has emerged as a novel paradigm for the future research. Similarly, bioadhesive delivery systems are explored that could significantly improve oral therapeutics for periodontal disease and mucosal lesions. A strategy is to target a wide range of molecular mediators of tissue destruction and hence arrest periodontal disease progression. Research into regenerating periodontal structures lost as a result of disease has also shown substantial progress in the last 25 years.

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

Local delivery of antimicrobials has been investigated as a possible method for controlling and treating periodontal disease. A number of antimicrobial agents have been studied both as adjunctive therapies with scaling and root planing and as stand-alone chemotherapies. More recent investigations have focussed on the delivery of antimicrobials in sustained-release formulations designed to maintain effective concentrations of drug within the periodontal pocket. This article provides an overview of the development of the use of locally-delivered metronidazole in periodontal therapy and the current state-of-the-art of the technique. It is concluded that treatment with local delivery of metronidazole seems to be as effective as scaling and root planing in untreated as well as in recall subjects. However, there are reasons to suggest that local delivery of metronidazole should not be used as a substitute for conventional treatment of periodontal disease, since side-effects of long-term use and repeated use are not known. The antibiotic regimen should preferably be used as an adjunct to surgical and non-surgical therapy.

Local metronidazole application in maintenance patients. Clinical and microbiological evaluation

The purpose of this investigation was to evaluate the clinical and microbiological effect of local antibiotic therapy in comparison with subgingival scaling and root planing in a randomized semi-masked study. Forty-six recall patients who completed systematic periodontal therapy 6 to 24 months prior to the study were enrolled. The inclusion requirements were at least one site with probing depth > or = 5 mm in each quadrant, no scaling, and no antibiotic therapy during the last 6 months. After randomization each patient received 2 different treatments: in 2 quadrants metronidazole 25% dental gel was applied subgingivally to the pockets at day 0 and day 7; scaling and root planing was carried out in the 2 other quadrants, one at day 0 and in the remaining quadrant at day 7. Subgingival microbiological samples were taken from each patient before treatment and on days 21, 91, and 175 after the treatment. The analyses were carried out by indirect immunofluorescence assay. At all treated sites probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) were recorded on days 0, 21, 91, and 175. Both treatments resulted in PD reduction and CAL gain. PD reduction was statistically significant (P < 0.01) for both treatment modalities after 6 months. The CAL gain was not significant for either treatment. There was no statistical significance between scaling and antibiotic therapy. Treponema denticola, Porphyromonas gingivalis, and Prevotella intermedia were significantly reduced after therapy; however, there were no statistically significant differences between treatments. If Actinobacillus actinomycetemcomitans was present before therapy, it was also present after treatment in both groups. The conclusion is that, in recall patients, local application of metronidazole and scaling and root planing showed similar clinical and microbiological effects without statistically significant differences.

Effects of topical metronidazole and tetracycline in treatment of adult periodontitis

The present study was performed to assess and compare the clinical healing and the microbiological findings following local application of metronidazole or tetracycline to augment subgingival scaling in previously untreated adult periodontitis sites. Eighteen patients with moderate to severe adult periodontitis at single-rooted teeth were selected. In each patient, 3 interproximal sites having comparable root anatomy, probing depth > or =5 mm and bleeding on probing were randomly assigned to 1 of 3 treatment groups: 1) two sessions of subgingival scaling and root planing; 2) similar to 1, with each treatment supplemented with a 25% metronidazole sustained release gel; 3) similar to 1 with each treatment supplemented with a 3% tetracycline ointment. The treatments were performed by 1 operator and the clinical variables probing depth, attachment level, and bleeding on probing were evaluated at baseline, 3 months and 6 months by a second blinded examiner. The microbiological findings were evaluated using a commercial test kit. The average probing depth reduction for the 3 groups at 6 months was 1.5 mm and the average gain of clinical attachment was 0.8 mm. There were no significant differences between the effects following topical application of the metronidazole gel or the tetracycline ointment. Scaling and root planing alone appeared as effective as the drug augmented regimens, although there was a weak but non-significant tendency for better results in sites treated with the antibiotic drugs. Actinobacillus actinomycetemcomitans was generally not detected; Prevotella intermedia was not significantly reduced, while Porphyromonas gingivalis was significantly reduced in all treatment groups. It was concluded that the augmentative effect of the metronidazole gel and the tetracycline ointment was comparable but small compared to scaling and root planing alone. The clinical importance of such small augmentation effects should be further evaluated.

Chemical treatment of periodontitis: local delivery of antimicrobials

Periodontitis is a bacterial infection. It appears in a generalised form but more often appears in local areas in a patient's mouth or is reduced to localised areas by mechanical treatment. Periodontitis lends itself well to treatment by means of a controlled local delivery system using an antimicrobial agent. Several products have been introduced or are in the process of clearing regulatory agencies. It is the goal of all local delivery systems to deliver high concentrations of an antimicrobial directly to the site of the periodontal infection. Concentrations of medication can be achieved considerably higher than could be obtained with systemic administration, while the systemic uptake of the medication is minimal. Five local delivery systems (tetracycline fibre, doxycycline polymer, chlorhexidine chip, minocycline ointment and metronidazole gel) are now available. Techniques for their use and the supporting scientific evidence are presented and indications for the use of the various systems are also discussed. These local delivery systems offer the clinician additional therapeutic procedures to aid in the treatment of the chronic inflammatory periodontal diseases.

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).

Subgingival controlled release of antimicrobial agents in the treatment of periodontal disease

Local drug delivery of antimicrobics by sustained release delivery systems can be used to treat periodontal disease. Advantages of these systems may include biodegradation of the system, maintaining high levels of antibiotic in the gingival crevicular fluid (GCF) for a sustained period of time and ease of use with high patient acceptance. This review will identify human in vivo clinical and microbiological studies. Sustained release formulations, application methods, clinical results and microbiological effects are discussed.

Short-term effects of triclosan on healing following subgingival scaling

The present clinical trial was performed to evaluate short-term effects of a triclosan-containing dentifrice/gel combination on soft tissue healing, when applied supra-/sub-gingivally at periodontal sites treated with scaling and root planing. 16 subjects with moderate periodontitis participated in a 2x 2-week, split-mouth designed clinical trial. 2 combinations of gel/dentifrice (the test combination containing triclosan) were used. 2 pairs of contralateral sites with probing pocket depth (PPD) > or 5 mm, and which bled on probing (BoP +) were selected in each patient as experimental units. A baseline examination included assessments of PPD, BoP, gingival index scores, plaque index scores, and the composition of the subgingival microbiota (dark-field microscopy). The assigned quadrant was anaesthetized and the teeth exposed to meticulous scaling and root planing. Immediately after the completion of mechanical therapy, either the test or control gel was applied subgingivally at the experimental sites. The volunteer was instructed to brush his/her teeth with an assigned dentifrice and to apply the gel (via a custom-made stent) supra-gingivally 2x daily for the following 2 weeks. He/she was recalled on day 7 for a second professional subgingival gel application. Re-examinations were carried out on days 2, 7 and 14 after treatment. 1-week wash-out periods separated the 2 experimental periods. The mean PPD reductions (between days 0 and 14) were 1.8 mm and 1.9 mm for the test and control gel/dentifrice sites. The reduction in BoP and gingival index scores was significantly greater during the test than during the control regimen. No significant differences were observed between the 2 regimens regarding plaque scores and composition of the subgingival microbiota. The findings from the present investigation demonstrated that triclosan, applied both sub- and supra-gingivally reduced soft tissue inflammation following scaling and root planing.

Sustained local delivery of chlorhexidine in the treatment of periodontitis: a multi-center study

The safety and efficacy of a degradable, subgingivally placed drug delivery system containing 2.5 mg chlorhexidine (CHX) were evaluated in a randomized, blinded, multi-center study of 118 patients with moderate periodontitis. A split-mouth design was used to compare the treatment outcomes of scaling and root planing (SRP) alone with the combined use of SRP and the CHX in pockets with probing depths of 5 to 8 mm. The two maxillary quadrants were used for the two treatment arms of the study. Scaling and root planing was performed at baseline only, while the CHX was inserted both at baseline and at 3 months. Clinical and safety measurements including probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) as well as gingivitis, plaque, and staining indices were recorded at baseline, and at 1, 3, and 6 months. The average PD reduction in the CHX-treated sites was significantly greater than in the sites receiving SRP alone at both 3 and 6 months with a mean difference of 0.42 mm (P < or = 0.01) at 6 months. The reduction in CAL at the treated sites was greater than at the SRP sites, although the difference was statistically significant at the 6-month visit only. An analysis of patients with initial probing depths of 7 to 8 mm (n = 56) revealed a significantly greater reduction in PD and CAL in those pockets treated with CHX compared to SRP at both 3 and 6 months. The mean differences between test and control sites at 6 months were 0.71 mm and 0.56 mm PD and CAL respectively.

Subgingival delivery of therapeutic agents in the treatment of periodontal diseases

This article reviews the current status of controlled local delivery of antibacterial agents in the treatment of periodontitis. The principle of local intrapocket delivery of antibacterial agents and their delivery are discussed. The dosage forms include fibers, film/slabs, and injectable systems, some of which are degradable, while others are not and need to be removed at the termination of the treatment. The antibacterial agents used cover a range of antibiotics as well as antiseptics, and the composition of the delivery systems, their reported use, and the clinical results are summarized. The use of these systems in clinical practice is relatively recent, and therefore their application and integration into the dental office are not yet clearly defined. Clinical applications that have been tested are critically reviewed, and clinical situations in which controlled delivery of antibacterial agents may prove to be clinically useful are suggested for scientific evaluation.

Gingival fluid tetracycline release from bioerodible gels

Intracrevicular antimicrobial therapy is consistent with the site-specific nature of periodontitis. Considerable research has focused on the use of nonresorbable fibers. However, a bioerodible system is desirable. The purpose of this study was to assess tetracycline release and safety following a single application of a syringable 35% tetracycline hydrochloride in a lactic-glycolic acid gel. 31 generally healthy adult volunteers (mean age = 59 years) were enrolled in and completed this randomized, double-blind eight day study. 2, 6-10 mm non-adjacent interproximal pockets that bled on pocket probing were chosen as experimental sites in each subject. I experimental site and the surrounding gingival crevice received small particle size tetracycline in gel while the other site received larger particle size tetracycline in gel. Gingival crevicular fluid (GCF) was collected prior to treatment and 15 min, 1, 2, 3, 4 and 8 days post-treatment. GCF tetracyline concentrations were determined by agar diffusion bioassay and GCF volume measurements. 61% and 71% of sites had > or = 100 micrograms/ml tetracycline 3 days following application of large (mean concentration = 430 +/- 92 micrograms/ml) and small particle gels (mean concentration = 418 +/- 70 micrograms/ml), respectively. 37% and 55% of sites had measurable tetracycline 8 days after placement of large (mean concentration = 86 +/- 31 micrograms/ml) and small particle gels (mean concentration = 293 +/- 79 micrograms/ml), respectively. The most common adverse event was "bitter taste" (10% of subjects). Based upon the reduction in probing depths and % of sites bleeding on probing at 8 days relative to pretreatment, and the absence of any serious adverse events, it is concluded that these bioerodible gels are safe, and since the bacteriostatic range for most putative periodontopathogens is in the 2-10 micrograms/ml range, the tetracycline levels observed at days 3 and 8 likely represent significant antimicrobial efficacy.

Evaluation of the long-term efficacy and safety of locally-applied minocycline in adult periodontitis patients

The objectives of the present study were to establish in a long-term investigation the safety as well as the clinical and microbiological efficacy of scaling and rootplaning combined with local application of 2% minocycline hydrochloride-gel versus placebo-gel in patients with moderate to severe chronic adult periodontitis. This was an 18 months, randomized, double-blind, parallel, comparative study, in which 20 healthy patients with moderate to severe chronic periodontitis participated. At baseline, all patients received professional oral hygiene-instruction and supra- and subgingival scaling and root planing. The minocycline-gel was applied subgingivally baseline, 2 weeks, 1, 3, 6, 9 and 12 months. Microbiological evaluation was carried out using DMDx to identify the following bacteria: Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, Campylobacter rectus, Fusobacterium nucleatum and Treponema denticola. In addition standard microbiological techniques were used for the detection of P. gingivalis, P. intermedia, P. micros, A. actinomycetemcomitans, C. rectus, F. nucleatum, C. albicans and Enterobacteriaceae. Results showed a statistically significant improvement for all clinical parameters irrespective of the treatment modality. No differences were observed between test and control with regard to probing depth and attachment level. The DMDx data showed a significant reduction in both the numbers and the prevalence over the 15 months period, but no significant difference between groups. Culture data showed that at baseline two-third were positive for P. gingivalis and P. intermedia. Analysis over the 18 month period showed no significant difference between the two treatment modalities. C. albicans and Enterobacteriaceae were detected only in small proportions at each time interval in a limited number of patients. No adverse reactions were observed during the trial period. The present patient group responded favourably to scaling and rootplaning, but did not benefit from an effect of local of minocycline. Subgingival debridement in combination with oral hygiene instruction by itself has been shown to be effective. It remains to be studied whether local application of minocycline can be effective as an adjunct to mechanical therapy in sites that respond poorly to conventional treatment.

Local and systemic chemotherapy in the management of periodontal disease: an opinion and review of the concept

Periodontal disease appears to arise from the interaction of pathogenic bacteria with a susceptible host. The main aims of disease management have been to establish a high standard of oral hygiene and to professionally and thoroughly debride the root surface Chemical agents could be considered for both aspects of management. Chemoprevention using supragingivally delivered agents such as chlorhexidine may be questioned for value in the pre-treatment hygiene phase but have well-established efficacy immediately preoperatively and during the post-operative weeks. Long-term maintenance use of chlorhexidine is problematic due to local side effects. Antiplaque toothpastes show modest benefits to gingivitis but are not proven to prevent recurrence of periodontitis. Chemotherapy may be directed at subgingival plaque, using antimicrobials, or at the host response using anti-inflammatory agents. Antimicrobials can be locally or systemically delivered. In most cases antimicrobial chemotherapy should be considered adjunctive to mechanical debridement. The advantages of local and systemic chemotherapy must be balanced against the disadvantages and potential side effects of agents. Antimicrobial chemotherapy offers little or no benefit to the treatment of most chronic adult periodontitis patients and should be reserved for the more rapid or refractory types of disease, and after the debridement phase. Despite the large number of studies there are insufficient comparative data to support any one local delivery system or systemic regimen as superior to another. Systemic versus local antimicrobials have not been compared to date. Host response modifying drugs such as non-steriodal anti-inflammatory drugs (NSAIDS) offer the potential to reduce breakdown and promote healing, including bone regeneration. However until more data are available, NSAIDs should not be used in the management of chronic periodontal diseases, there being no specific agent(s) or regimen established for use. Chemotherapy has an important place in the management of chronic periodontal diseases but routine use must be considered as an over prescription of these valuable agents.

Topical metronidazole application compared with subgingival scaling. A clinical and microbiological study on recall patients

The aim of this study was to compare the topical application of a metronidazole 25% dental gel with subgingival scaling. 30 patients from the recall program participated in this open randomised study with split-mouth design. Pocket probing depths (PPD) and bleeding on probing (BOP) were measured before and 2, 12 and 24 weeks after the end of the treatment period. In addition, subgingival plaque samples were taken from all mesial sites and analysed with dark-field microscopy. All patients had at least 1 tooth in each quadrant with a PPD of 5 mm or more that should bleeding on probing, when entering the study. The treatment consisted of 2 applications of the dental gel in 2 randomly selected quadrants (on days 0 and 7) as well as simultaneous subgingival scaling of the remaining quadrants. Oral hygiene instruction was given on day 21. The average PPD and the average frequency of BOP were calculated for all sites with an initial PPD of 5 mm or more and continued at each examination, using the same sites. The statistical analyses showed that both treatments were effective in reducing PPD and BOP over the 6-month period. At the end of the follow-up period, the mean reduction in PPD was 1.3 mm after gel treatment and 1.5 mm after subgingival scaling. BOP was reduced by 35% and 42%, respectively. No significant differences between the 2 treatments were detected. Dark-field microscopy showed a shift toward a more healthy microflora for both treatment modalities; this persisted throughout the 6-month period. Application of a 25% metronidazole dental gel on recall patients seems to be as effective on the investigated clinical and microbiological parameters as subgingival scaling.

Elimination of Elyzol 25% Dentalgel matrix from periodontal pockets

Elyzo 25% Dentalgel (EDG) which is developed for use in the treatment of periodontitis is a suspension of metronidazole benzoate (40%) in a mixture of glyceryl mono-oleate (GMO) and triglyceride (sesame oil). Metronidazole can be detected in the periodontal pockets 24-36 h after application. The aim of the present study was to estimate the period of time that the gel matrix persists on periodontal pockets after 1 application of EDG. 12 patients were included in the study. From each patient, 1 sample was taken before and immediately after, and 1, 2, 3, 4, 5, 6, 8, 12 and 24 h after application. Subgingival scaling followed by absorption of gingival crevicular fluid with filter paper was used for sampling. The sampling unit was 1 tooth. Each sample was assayed for the amount of GMO and oleic acid (a degradation product of GMO) by means of high-performance liquid chromatography (HPLC) with UV detection. To allow determination of the GMO dose applied into the pockets and to estimate the recovery rate of the sampling method, 1 tooth in each patient was selected for sampling as soon as the gel had set, i.e., about 10 min after application. Only in 1 patient was a detectable amount of GMO within the pocket revealed 24 h after application. This amount was approximately 0.5% of the mean GMO dose applied around 1 tooth. GMO was found no longer than 12 h in the remaining patients.

Evaluation of the efficacy of a redox agent in the treatment of chronic periodontitis

A redox dye, methylene blue, was compared with subgingival root surface debridement and sterile water in the treatment of adult periodontitis. Plaque and gingival indices, bleeding on probing, and microbiological samples were obtained at baseline, and at 1, 4, 8 and 12 weeks following treatment. All subjects had matched pockets in each of the 4 quadrants, of 5 mm or more. One treatment consisted of 0.1% methylene blue gel irrigated professionally at 0, 1 and 4 weeks, and by subjects at days in between up to 4 weeks, at chosen sites within a randomly selected quadrant (split-mouth design). A 2nd treatment was sterile water irrigation as above. A 3rd quadrant received subgingival debridement, and sites in the 4th received methylene blue incorporated into a slow-release device of a biodegradable collagen alginate vicryl composite. All sites showed improvements in clinical and microbiological parameters. However, no statistically significant differences between treatment types were found for clinical measurements. Although plaque index tended to increase after week 1, gingival index was reduced, as was the papilla bleeding index. Probing depth reductions were approximately 1.2 mm for all treatments. Microbiological variables showed an increase in cocci and a decrease in motile organisms for all groups, the latter reaching statistical significance for subgingival debridement. The reductions in spirochaetes were significant for subgingival debridement and methylene blue by slow-release. Culture demonstrated an increase in the aerobe:anaerobe ratio for all groups, which was statistically significant initially (weeks 1 and 4) for subgingival debridement. Methylene blue was also effective statistically in improving this ratio, both by irrigation and slow-release (week 4). Methylene blue also significantly reduced the numbers of black-pigmented anaerobes during the trial period, both by irrigation and slow-release, which sterile water and subgingival debridement failed to do. No serious adverse experiences were seen, however, significantly greater morbidity was associated with subgingival debridement. These results clearly demonstrate that in altering the microflora to one that is more compatible with periodontal health, methylene blue treatment is comparable, or even better, than the currently standard treatment of subgingival debridement, and is better tolerated.

Influence of a single application of subgingival chlorhexidine gel or tetracycline paste on the clinical parameters of adult periodontitis patients

The clinical effects of subgingivally placed 1% chlorhexidine gel (w/w) and 40% tetracycline (w/w) paste in periodontal pockets of 22 adult periodontitis patients were studied. The 2 agents were applied following scaling and root planing in pockets exceeding 4 mm. The patients were randomly divided into 3 groups: (a) scaling and root planing (SCRP) only, the control group; (b) corsodyl gel+SCRP; (c) Tetracycline paste+SCRP. Gel or paste were gently applied using a syringe with a blunt needle until the selected pocket was overfilled. Evaluations were made of clinical parameters including the plaque index (PI), gingival index (GI), bleeding index (GI-S), probing pocket depths, probing attachment levels and position of the gingival margin. The results suggested that all the treatment modalities were effective in producing statistically significant improvements in clinical parameters. It was concluded that the conventional treatment modalities were essential in the treatment of periodontal diseases, but in view of the structure of the periodontal pocket and adjacent complex root surface, subgingival drug application in certain cases, might also provide adjunctive improvement.