Local delivery of chlorhexidine gluconate (PerioChip) in periodontal maintenance patients

A Novel Antimicrobial Hydrogel for the Management of Periodontal Diseases

OBJECTIVES

This study aimed to synthesise a drug-delivery system based on a porous polymer hydrogel, with antimicrobial properties against Porphyromonas gingivalis and potential to be used in tissue regeneration.

MATERIAL AND METHODS

2-Hydroxyethyl methacrylate monomers were polymerised using thermal and photoactivation in the presence of silver nitrate (AgNO₃) and/or chlorhexidine digluconate. Poly-2-hydroxyethyl methacrylate (pHEMA) hydrogels containing silver nanoparticles (AgNPs) and/or 0.12% chlorhexidine (CHX) were produced and characterised using cryo-SEM and confocal microscopy. Hydrogel degradation and leaching of AgNP were tested for 1.5 months. The antimicrobial properties were tested against P. gingivalis using broth culture system and disk diffusion tests.

RESULTS

Our methodology manufactured porous polymeric hydrogels doped with AgNPs and CHX. Hydrogels showed a successful delivery of CHX and sustainable release of AgNPs in a steady hydrogel degradation rate determined based on the weight loss of samples. Hydrogels with AgNPs or CHX had a significant antimicrobial effect against P. gingivalis, with CHX-hydrogels exhibiting a stronger effect than AgNP-hydrogels in the short-term assessment. AgNP-CHX hydrogels showed a compounded antimicrobial effect, whereas control hydrogels containing neither AgNPs nor CHX had no influence on bacterial growth (P < .05).

CONCLUSIONS

The dual-cured pHEMA hydrogel loaded with antimicrobial agents proved to be an efficient drug-delivery system against periodontopathogens, with the potential to be used as a scaffold for tissue regeneration.

The effect of (-)-epigallocatechin gallate as an adjunct to non-surgical periodontal treatment: a randomized clinical trial

Background

EGCG is proven to be of good effect to relieve periodontal inflammation, but it has not been applied as a local delivery medicine in patients with periodontitis widely. The aim of this clinical trial was to evaluate the adjunctive effect of (-)-epigallocatechin gallate (EGCG) aqueous solution as a coolant during scaling and root planing in the management of chronic periodontitis.

Methods

A double-blind, randomized controlled study was performed on 15 patients with moderate to severe chronic periodontitis. The bilateral maxillary teeth were randomly divided into the test side and the control side on every individual. On the control side, the periodontal therapy was routinely performed. And on the test side, in the process of periodontal therapy, the distilled water in the ultrasonic scaler was replaced with a 5-mg/mL EGCG solution. The probing depth (PPD), clinical attachment level (CAL), bleeding index (BI), gingival index (GI), and plaque index (PI) were recorded at baseline and 6 and 12 weeks after the treatment.

Results

PPD, CAL, BI, GI, and PI generally improved after treatment in both groups. At the sixth week and the twelfth week of review, PPD, CAL, GI, and PI had no statistical difference (p >0.05) between the two groups. At the review of the twelfth week, BI on the test side decreased significantly (p <0.05).

Conclusions

Using EGCG solution as the irrigant instead of water has an additional benefit on the bleeding index at the 12-week review. However, the rest clinical parameters had no additional benefit.

Trial registration

ClinicalTrials.gov ChiCTR2000029831, date of registration: Feb 15, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06298-6.

Synthesis, Drug Release, and Antibacterial Properties of Novel Dendritic CHX-SrCl2 and CHX-ZnCl2 Particles

This work demonstrated for the first time the synthesis of novel chlorhexidine particles containing strontium and zinc, to provide an effective, affordable, and safe intervention in the treatment of recurrent infections found in Medicine and Dentistry. The CHX-SrCl₂ and CHX-ZnCl₂ particles were synthesized by co-precipitation of chlorhexidine diacetate (CHXD) and zinc chloride or strontium chloride, where particle size was manipulated by controlling processing time and temperature. The CHX-ZnCl₂ and CHX-SrCl₂ particles were characterized using SEM, FTIR, and XRD. UV-Vis using artificial saliva (pH 4 and pH 7) was used to measure the drug release and ICP-OES ion release. The antibacterial properties were examined against P. gingivalis, A. actinomycetemcomitans, and F. nucleatum subsp. Polymorphum, and cytotoxicity was evaluated using mouse fibroblast L929 cells. The novel particles were as safe as commercial CHXD, with antibacterial activity against a range of oral pathogens. UV-Vis results run in artificial saliva (pH 4 and pH 7) indicated a higher release rate in acidic rather than neutral conditions. The CHX-ZnCl₂ particles provided the functionality of a smart Zinc and CHX release, with respect to environmental pH, allowing responsive antibacterial applications in the field of medicine and dentistry.

New Frontiers on Adjuvants Drug Strategies and Treatments in Periodontitis

Causes of the progression of periodontitis such as an imbalance between the immune response by the host by the release of inflammatory mediators in the response of the oral pathogenic dysbiotic biofilm have been identified. New insights on specific cell signaling pathways that appear during periodontitis have attracted the attention of researchers in the study of new personalised approaches for the treatment of periodontitis. The gold standard of non-surgical therapy of periodontitis involves the removal of supra and subgingival biofilm through professional scaling and root planing (SRP) and oral hygiene instructions. In order to improve periodontal clinical outcomes and overcome the limitations of traditional SRP, additional adjuvants have been developed in recent decades, including local or systemic antibiotics, antiseptics, probiotics, anti-inflammatory and anti-resorptive drugs and host modulation therapies. This review is aimed to update the current and recent evolution of therapies of management of periodontitis based on the adjunctive and target therapies. Moreover, we discuss the advances in host modulation of periodontitis and the impact of targeting epigenetic mechanisms approaches for a personalised therapeutic success in the management of periodontitis. In conclusion, the future goal in periodontology will be to combine and personalise the periodontal treatments to the colonising microbial profile and to the specific response of the individual patient.

Use of chlorhexidine chip after scaling and root planning on periodontal disease: A systematic review and meta-analysis

Objective

This systematic review aims to assess the efficacy chlorhexidine chip as an adjunctive therapy of scaling and root planning on periodontal disease treatment.

Material and methods

This study follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA) and was registered in the PROSPERO database (CRD42019148221). The search was performed in PubMed/MEDLINE, Scopus, and Cochrane databases until April 2020. The PICO question was: “Is the chlorhexidine chip (CHX) effective as an adjunctive therapy of scaling and root planning on periodontal disease treatment?”. Inclusion criteria involved: randomized controlled clinical trials, with a minimum of 15 patients included on the sample and each patient has two sites of probing depth of ≥5 mm; The minimum follow up was at least 1 months of follow-up and the outcomes present in the studies probing depth (PD), plaque index (PI) and clinical attachment level (CAL) after scaling and root planning (SRP).

Results

After searching the databases, 13 articles were selected for qualitative and 8 for quantitative analysis. Were included 427 patients, with a mean age of 45.6 years. The results shown that the association of chlorhexidine chips to scaling and root planning reduce periodontal pocket depths (P < 0.00001; MD −0.77 [CI −1.0 to −0.55]; I² = 23%, P = 0.24), gain on the clinical attachment level (P < 0.0001; MD −0.57 [CI −0.86 to −0.27]; I² = 33%, P = 0.18P < 0.0001) and reduction on plaque index (P = 0.04; MD −0.23 [CI −0.45 to −0.01]; I² = 91%, P < 0.00001).

Conclusions

Thus, we can conclude that chlorhexidine chip when used associated to scaling and root planning promoted a significant improvement the reduction of periodontal diseases.

Adjunctive local treatments for patients with residual pockets during supportive periodontal care: A systematic review and network meta-analysis

AIM

This systematic review and network meta-analysis aimed to evaluate the efficacy of adjunctive locally delivered antimicrobials, compared to subgingival instrumentation alone or plus a placebo, on changes in probing pocket depth (PPD) and clinical attachment level (CAL), in patients with residual pockets during supportive periodontal care.

MATERIALS AND METHODS

Literature search was performed with electronic databases and by hand until 31 May 2020. Primary outcome was the changes in PPD. The treatment effects between groups were estimated with weighted mean differences (WMD) with 95% confidence intervals (CI) and prediction intervals (PI) by using random-effects network meta-analysis.

RESULTS

Twenty-two studies were included. Significantly greater PPD reduction was achieved in chlorhexidine chip group (WMD: 0.65 mm, 95% CI: 0.21-1.10) and tetracycline fibre group (WMD: 0.64 mm, 95% CI: 0.20-1.08) over 6-month follow-up. Other adjunctive antimicrobial agents achieved non-significant improvements compared to scaling and root planing alone. All differences between adjunctive therapies were statistically non-significant. Similar findings were observed for CAL gain.

CONCLUSION

Adjunctive local antimicrobial agents achieved small additional PPD reduction and CAL gain in residual pockets for a follow-up of up to 6 months. Tetracycline fibre and chlorhexidine chip achieved better results than other antimicrobials.

Development and Evaluation of a Polyvinylalcohol -Cellulose Derivative-Based Film with Povidone-Iodine Predicted for Wound Treatment

The aim of this study was to develop and assess a polyvinyl alcohol-cellulose derivatives-based film with incorporated povidone-iodine (PVP-I) predicted for applications in the treatment of periodontitis. Films were fabricated by solvent-casting, and their physical characteristics, such as their surface and structure morphology, mechanical properties, and disintegrating time, were evaluated. For in vitro iodine release studies and evaluation, the antimicrobial activity was tested using a modified disc diffusion method against five microbial strains. For further use, we selected the film with polyvinyl alcohol-hydroxypropyl methylcellulose (PVA/HPMC_B) based on acceptable physicochemical properties. To assess the subacute toxicity of the film composition, the tissue regeneration process was tested in rats and compared to a conventional dressing commonly used in wound healing (Spongostan). Seven days after implantation, dorsal skin sections and blood samples (n = 10, in total n = 30) were examined. The wound area, epithelium, and dermis were evaluated microscopically, while the blood collected from the rats underwent biochemical analysis. The blood biochemistry results were comparable in all three groups. No significant histological differences between the Spongostan and the placebo film developed after subcutaneous implantation were observed. In contrast, the inflammation stage was reduced and the “scar” in the dermis was smaller when PVP-I and PVA/HPMC_B films were used. A smaller local inflammatory response inflicted less tissue damage, leading to the activation of subsequent regeneration phases and restoration of the area to its original state. The results obtained confirmed that PVP-I incorporated into PVA-hydroxypropyl methylcellulose film is a promising drug carrier, working faster and more effectively than the other two dressing materials evaluated. These developments provide a promising alternative in tissue regeneration and the wound healing process.

Antiseptics as adjuncts to scaling and root planing in the treatment of periodontitis: a systematic literature review

BACKGROUND

Periodontitis is microbially-associated, host-mediated inflammatory condition that results in loss of periodontal attachment. The goals of periodontal therapy include arresting the disease progression, establishing healthy, stable, maintainable periodontal conditions. A fundamental strategy of treating periodontitis is scaling and root planning (SRP), however its efficacy may be restricted in areas inaccessible for mechanical instrumentation. As periodontitis is infectious in nature, it might be helpful to use additional antimicrobial adjuncts, in order to eliminate or inactivate pathogenic microflora. The aim of this study is to evaluate the current evidence regarding the potential clinical benefits of using additional antiseptics for SRP in nonsurgical periodontal therapy.

METHODS

An electronic literature search was conducted in the MEDLINE (Ovid) and Cohrane Central Register of Controlled Trials (CENTRAL) databases for articles published between January 1, 2000 and September 22, 2019. Randomized controlled clinical trials in English that compare the effectiveness of one or more antiseptic agents as adjuncts to SRP with a follow-up of ≥6 months were included. A meta-analysis using the random-effects model was performed on the selected qualifying articles.

RESULTS

The search resulted in 12 articles that met the inclusion criteria. Based on the vehicle employed to deliver the antiseptic agent, studies were divided into adjunctive sustained-release antiseptics (gels, chips and varnish) and adjunctive irrigation with antiseptics. The meta-analysis demonstrated significant improvements in probing depth (PD) reduction (p = 0.001), clinical attachment level (CAL) gain (p = 0.001), and bleeding on probing (BOP) values (p = 0.001) following the adjunctive subgingival application of sustained-release antiseptics. Additional subgingival irrigation with antiseptics failed to show significant improvements in PD (p = 0.321), CAL (p = 0.7568), or BOP values (p = 0.3549) over SRP alone.

CONCLUSIONS

Adjunctive subgingivally delivered antiseptics with a sustained-release delivery have significant clinical benefits compared to SRP alone.

In-situ forming implants loaded with chlorhexidine and ibuprofen for periodontal treatment: Proof of concept study in vivo

Control of infection and inflammation is crucial for the success of periodontal treatment. In this study, in-situ forming implants (ISFI) loaded with chlorhexidine dihydrochloride (CHX) and ibuprofen (IBU) were developed and tested to optimize periodontal treatment outcomes. Release profiles were promising. Exposure to 1.5% and 5.3% CHX-IBU loaded ISFI's release media decreased significantly the P. gingivalis growth up to 20-fold and 35-fold, respectively, after 48 h (p < 0.05). The metabolic activity assay of gingival epithelial cells (EC) demonstrated 1.5% CHX-IBU-loaded ISFI to be non-toxic, therefore, it was selected for further experimentation. Furthermore, significant down-regulation of TNF-α release (34% at 6 h and 43% at 24 h, p < 0.05) in P. gingivalis lipopolysaccharide (Pg-LPS) stimulated EC exposed to 1.5% CHX-IBU ISFI release medium was demonstrated by ELISA. In vivo, 1.5% CHX-IBU ISFI was injected into the periodontal pocket in an experimental periodontitis mouse model and the reduction in inflammation and improvement in periodontal wound healing was evaluated through inflammatory cell scoring and histomorphometry at 7- and 15-days post-treatment. The results indicate that CHX-IBU loaded ISFI could be efficient as adjuvant to periodontal therapy for the control of infection and inflammation. Moreover, other (e.g., pro-regenerative) drugs could be incorporated into ISFI to further improve periodontal treatment outcomes.

Nonsurgical Treatment of Peri-implantitis Without Eliminating Granulation Tissue: A 3-Year Study

OBJECTIVES

The purpose of this study was to evaluate a nonsurgical approach toward peri-implantitis by means of mechanical debridement and local detoxification leaving granulation tissue into the peri-implant pockets.

MATERIALS AND METHODS

An analysis was performed on the outcomes of 2 nonsurgical protocols: mechanical debridement plus chemical detoxification with 0.2% chlorhexidine and chlortetracycline hydrochloride (test), and mechanical debridement alone (control). Measures were collected at baseline, 3, 24, and 36 months after treatment.

RESULTS

Seventy-five implants with peri-implantitis were included. At a 36-month evaluation, mean pocket probing depth was 3.15 ± 0.32 mm for the test group and 5.97 ± 0.90 mm for the control group, the difference being significant. An improvement of marginal bone level was recorded for the test group, whether the control group showed a further marginal bone loss. Treatment success was 100% in the test group and 31.4% in the control group.

CONCLUSION

Nonsurgical implant debridement alone seemed not efficient in the treatment of peri-implantitis. Further longitudinal studies are required to evaluate the efficacy of mechanical debridement with chemical detoxification and removal of granulation tissues against mechanical debridement with chemical detoxification alone.

The effect of green tea as an adjunct to scaling and root planing in non-surgical periodontitis therapy: a systematic review

OBJECTIVE

To provide a systematic overview on the efficacy of green tea catechin as an adjunct to scaling and root planing (SRP) in terms of probing pocket depth (PPD).

MATERIALS AND METHODS

A systematic literature search was performed using electronic databases in PubMed, Scopus, Medline, Cochrane, CINAHL, and Web of Science on randomized clinical trials up to January 2017. The research question was posed in accordance with PRISMA guidelines.

RESULTS

The search provided 234 studies. After analyzing the full texts, five studies were included, with four studies qualifying for meta-analysis. Mean PPD reduction was significantly higher (α = 0.05) when green tea catechin was used as an adjunct to SRP (test group) than with SRP alone (control group). The difference in the reduction was 0.74 mm [0.35-1.13; 95% CI].

CONCLUSION

The local application of green tea catechin as an adjunct to SRP may result in a beneficial reduction in PPD. Due to the highly heterogeneous data and some risk of bias, however, this data still needs to be interpreted with caution.

CLINICAL RELEVANCE

The finding suggests that green tea catechin may be a topical adjunct to SRP without negative side effects.

Efficacy of grape seed extract gel in the treatment of chronic periodontitis: A randomized clinical study

AIM

The aim of the present study was to assess the effectiveness of applying grape seed extract (GSE) gel in periodontal pockets for the treatment of chronic periodontitis.

METHODS

Eighty-six sites with pocket depth (PD) >4 mm were selected from five systemically-healthy patients in whom scaling, and root planing were performed, and oral instructions were given, a week earlier. PD, gingival index (GI), plaque index (PI), and bleeding on probing (BOP) were measured, and sites were then divided into the control group (N = 38) and GSE group (N = 48). Four doses of formulated 2% mucoadhesive GSE gel were applied to GSE group sites at baseline visit (T0), and 3, 6, and 9 days after T0. Similarly, a control gel was applied to the control sites. PD, PI, GI and BOP were re-evaluated after 4 weeks and 6 months of first gel application.

RESULTS

Paired t test for both the control and GSE groups showed a significant reduction for all variables after 6 months of gel application (P < .05). The independent t test showed a significant difference (P < .05) only in the reduction of gingival index (mean: 0.85 ± 0.77 for control and 1.3 ± 0.8 for GSE) and plaque index (mean: 0.75 ± 0.71 for control and 1.12 ± 0.7 for GSE).

CONCLUSION

The subgingival application of the formulated 2% mucoadhesive GSE gel showed significant improvement in the PI and GI only.

Supportive periodontal therapy (SPT) for maintaining the dentition in adults treated for periodontitis

BACKGROUND

Periodontitis is a bacterially-induced, chronic inflammatory disease that destroys the connective tissues and bone that support teeth. Active periodontal treatment aims to reduce the inflammatory response, primarily through eradication of bacterial deposits. Following completion of treatment and arrest of inflammation, supportive periodontal therapy (SPT) is employed to reduce the probability of re-infection and progression of the disease; to maintain teeth without pain, excessive mobility or persistent infection in the long term, and to prevent related oral diseases.According to the American Academy of Periodontology, SPT should include all components of a typical dental recall examination, and importantly should also include periodontal re-evaluation and risk assessment, supragingival and subgingival removal of bacterial plaque and calculus, and re-treatment of any sites showing recurrent or persistent disease. While the first four points might be expected to form part of the routine examination appointment for periodontally healthy patients, the inclusion of thorough periodontal evaluation, risk assessment and subsequent treatment - normally including mechanical debridement of any plaque or calculus deposits - differentiates SPT from routine care.Success of SPT has been reported in a number of long-term, retrospective studies. This review aimed to assess the evidence available from randomised controlled trials (RCTs).

OBJECTIVES

To determine the effects of supportive periodontal therapy (SPT) in the maintenance of the dentition of adults treated for periodontitis.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 8 May 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 5), MEDLINE Ovid (1946 to 8 May 2017), and Embase Ovid (1980 to 8 May 2017). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating SPT versus monitoring only or alternative approaches to mechanical debridement; SPT alone versus SPT with adjunctive interventions; different approaches to or providers of SPT; and different time intervals for SPT delivery.We excluded split-mouth studies where we considered there could be a risk of contamination.Participants must have completed active periodontal therapy at least six months prior to randomisation and be enrolled in an SPT programme. Trials must have had a minimum follow-up period of 12 months.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results to identify studies for inclusion, assessed the risk of bias in included studies and extracted study data. When possible, we calculated mean differences (MDs) and 95% confidence intervals (CIs) for continuous variables. Two review authors assessed the quality of evidence for each comparison and outcome using GRADE criteria.

MAIN RESULTS

We included four trials involving 307 participants aged 31 to 85 years, who had been previously treated for moderate to severe chronic periodontitis. Three studies compared adjuncts to mechanical debridement in SPT versus debridement only. The adjuncts were local antibiotics in two studies (one at high risk of bias and one at low risk) and photodynamic therapy in one study (at unclear risk of bias). One study at high risk of bias compared provision of SPT by a specialist versus general practitioner. We did not identify any RCTs evaluating the effects of SPT versus monitoring only, or of providing SPT at different time intervals, or that compared the effects of mechanical debridement using different approaches or technologies.No included trials measured our primary outcome 'tooth loss'; however, studies evaluated signs of inflammation and potential periodontal disease progression, including bleeding on probing (BoP), clinical attachment level (CAL) and probing pocket depth (PPD).There was no evidence of a difference between SPT delivered by a specialist versus a general practitioner for BoP or PPD at 12 months (very low-quality evidence). This study did not measure CAL or adverse events.Due to heterogeneous outcome reporting, it was not possible to combine data from the two studies comparing mechanical debridement with or without the use of adjunctive local antibiotics. Both studies found no evidence of a difference between groups at 12 months (low to very low-quality evidence). There were no adverse events in either study.The use of adjunctive photodynamic therapy did not demonstrate evidence of benefit compared to mechanical debridement only (very low-quality evidence). Adverse events were not measured.The quality of the evidence is low to very low for these comparisons. Future research is likely to change the findings, therefore the results should be interpreted with caution.

AUTHORS' CONCLUSIONS

Overall, there is insufficient evidence to determine the superiority of different protocols or adjunctive strategies to improve tooth maintenance during SPT. No trials evaluated SPT versus monitoring only. The evidence available for the comparisons evaluated is of low to very low quality, and hampered by dissimilarities in outcome reporting. More trials using uniform definitions and outcomes are required to address the objectives of this review.

Evaluation of Turmeric Chip Compared with Chlorhexidine Chip as a Local Drug Delivery Agent in the Treatment of Chronic Periodontitis: A Split Mouth Randomized Controlled Clinical Trial

AIMS AND OBJECTIVE

The aim of this study was to evaluate and compare the effect of chlorhexidine (CHX) chip and turmeric chip as a local drug delivery (LDD) agent in the treatment of patients with chronic periodontitis.

MATERIALS AND METHODS

A total of 120 sites with pocket depths 5-8 mm were chosen as a split mouth design at 3 sites in the same patient. Selected sites were randomly divided into three groups to receive CHX chip in addition to scaling and root planing (SRP) in group A, turmeric chip in addition to SRP in group B, and SRP only in group C. Clinical parameters, that is, plaque index (PI), gingival index (GI), probing pocket depth (PPD), and relative attachment level (RAL) were recorded at baseline, 1 month, and 3 months interval.

RESULT

On applying statistical analysis, results revealed that there was a significant reduction in all the clinical parameters, that is, PI, GI, PPD, and gain in RAL from baseline to 1 month and 3 months in all the three groups. These results were found to be significantly high in the CHX group and turmeric group than in the SRP group. Also, the results in both the test groups were maintained till the end of the study periods, but SRP group showed a significant deterioration after 1 month as was seen by increase in PPD and decrease in RAL scores after 3 months in the SRP group.

CONCLUSION

Both the treatment modalities with the application of LDD as an adjunct to SRP proved to be equally beneficial in the treatment of chronic periodontitis.

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

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

Physical key properties of antibiotic-free, PLGA/HPMC-based in-situ forming implants for local periodontitis treatment

In-situ forming implants (ISFI) offer an interesting potential for the treatment of periodontitis, allowing for time-controlled drug release directly at the site of action (which is difficult to reach). For this purpose, ISFI loaded with antibiotics have been reported in the literature. But the use of antibiotic drugs at low doses over prolonged periods of time can lead to the development of bacterial resistances. This risk should be avoided. The aim of this study was to develop a novel type of in-situ forming implants, loaded with the antiseptic drug chlorhexidine. Special emphasis was placed on the physical properties of the systems, assuring a reliable residence time in the periodontal pockets of patients suffering from periodontitis. In particular, the risk of premature, accidental loss of the formulations due to mechanical stress (e.g. during tooth brushing and chewing) was to be reduced. Two commercially available drug products for local periodontitis treatment were studied for reasons of comparison: Chlo-site and Parocline. The syringeability and swelling behavior of the formulations were investigated, and the hardness, springiness, resilience and "stickiness" of the systems determined using extracted human teeth. Interestingly, the novel in-situ forming implants, based on PLGA/HPMC and being free of antibiotics, exhibit highly promising physical key properties: They are intensively sticking to teeth' surfaces and provide adequate mechanical strength to assure reliable and prolonged residence times in periodontal pockets. In contrast, the commercial drug products showed limited adhesion and either rapidly shrank (Chlo-site), or substantially swelled and were mechanically very weak (Parocline).

Systemic antibiotics in the treatment of periodontitis

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS AND PRACTICAL IMPLICATIONS

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

Different methods for subgingival application of chlorhexidine in the treatment of patients with chronic periodontitis

OBJECTIVE

The aim of this study was to evaluate clinical efficacy of different chlorhexidine gluconate (CHX) preparations applied subgingivally as an adjunct to scaling and root planing (SRP).

MATERIAL AND METHODS

A total of 120 periodontal pockets was included in this randomized, controlled, split mouth designed study. According to protocols used in treatment, periodontal pockets were assigned to experimental and control groups as follows: CHX solution as an addition to SRP versus control SRP group; CHX gel as an addition to SRP versus control SRP; CHX chip as an addition to SRP versus control SRP group. Following clinical parameters were recorded at baseline, one and three months after the baseline: plaque index (PI), probing pocket depth (PPD), bleeding index (BI) and clinical attachment level (CAL).

RESULTS

The most significant improvements were found concerning PI in CHX solution with SRP and CHX gel with SRP groups over controls at one month recall, as well as concerning BI and PPD in CHX chip with SRP group over SRP alone at three-month recall.

CONCLUSION

Results of this study favour combination therapy using CHX chip as an adjunct to SRP due to greater improvements in BI and PPD compared to those obtained by SRP alone in the treatment of chronic periodontitis.

Adjunctive Effects of A Piscean Collagen-Based Controlled-Release Chlorhexidine Chip in the Treatment of Chronic Periodontitis: A Clinical and Microbiological Study

INTRODUCTION

PerioChip a bovine origin gelatine based CHX chip has shown beneficial effects in the management of Chronic Periodontitis. A new fish collagen based CHX chip similar to PerioChip is currently available; however this product has not been thoroughly researched.

AIM

The aim of the present study was to evaluate the effectiveness of a new Piscean collagen-based controlled-release chlorhexidine chip (CHX chip) as an adjunctive therapy to scaling and root planing (SRP).

SETTINGS AND DESIGN

The study was conducted as a randomised, split-mouth, controlled clinical trial at Krishnadevaraya College of Dental Sciences, Bangalore, India.

MATERIALS AND METHODS

In a split-mouth study involving 20 sites in 10 patients with chronic periodontitis, control sites received scaling and root planing and test sites received scaling and root planing (SRP) and the intrapocket CHX chip placement as an adjunct. Subgingival plaque samples were collected from both control and test sites at baseline, 11 days and 11 weeks and the anaerobic colony count were assessed. Clinical parameters that were recorded at baseline and 11 weeks were gingival index, Plaque index, Probing pocket depth (PPD), and Clinical attachment level (CAL). Plaque index was recorded additionally at 11 days.

RESULTS

In the test group there was a statistically significant reduction in the total anaerobic colony count, gingival index and plaque scores from baseline as compared to control sites at all time intervals. An additional 0.8mm reduction in mean probing pocket depth was noted in the test group. Gain in Clinical attachment level was comparable in both groups.

CONCLUSION

The adjunctive use of the new collagen-based CHX chip yielded significant antimicrobial benefit accompanied by a reduction in probing depth and a clinical attachment level gain as compared to SRP alone. This suggests that it may be a useful treatment option of nonsurgical periodontal treatment of chronic periodontitis.

Novel therapeutic approach for the treatment of periodontitis by curcumin

AIMS AND OBJECTIVES

The aim of the present study was to evaluate the clinical and microbiological efficacy of locally delivered 1% curcumin gel as an adjunct to scaling and root planing in the treatment of chronic periodontitis.

MATERIALS AND METHODS

The study group consisted of 25 patients, belonging to both sex, aged between 21-45 years. All patients diagnosed as chronic periodontitis with periodontal pockets of depth >5mm bilaterally were randomly selected. A split mouth design was followed and the patients received a complete prophylaxis including scaling and root planing. Examination of plaque index, bleeding index, probing pocket depth and clinical attachment level were measured for each patient. The test group received 1% curcumin gel along with scaling and root planing whereas the control group received scaling and root planing alone followed by microbiological samples taken at baseline, 1, 3 and 6 months interval.

RESULTS

The 1% curcumin gel appeared to provide significant improvements in clinical parameters. Microbiological counts of Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum and capnocytophaga showed significant reduction in periopathogens at the test sites after six months when compared with that of control sites.

CONCLUSION

Locally delivered 1% curcumin gel was more effective in inhibiting the growth of oral bacteria when used as an adjunct to SRP in the treatment of chronic periodontitis.

Effect of chlorhexidine chip in the treatment of chronic periodontitis

AIMS

The evaluation of clinical and specific microbiological changes associated with chlorhexidine chip in the chronic periodontitis patients.

MATERIALS AND METHODS

A total of 30 chronic periodontitis patients (aged 20-65 years) having pocket depth of ≥5 mm in molar teeth were selected and randomly divided into following treatment groups: Group 1 - Scaling and root planning (SRP), Group 2 - SRP along with chlorhexidine chip and Group 3 - Only chlorhexidine chip. The clinical and microbial parameters were recorded at baseline and 1 and 3 months post-treatment as above. Benzoyl-DL-arginine-naphthylamide (BANA) chair side test was used for estimation of specific microbiota.

RESULTS

Gingival index, probing pocket depth and clinical attachment level scores in selected teeth within the groups at different time intervals was significantly (P < 0.001) different. Although, the comparison between groups for specific microbiota in selected sites at different intervals was not statistically significant at baseline and 1 month, it reached statistical significance at 3(rd) month post-treatment. Although significant reductions in percentage of BANA positive sites were observed in all three groups, the Group 2 had significantly greater percentage of BANA negative sites.

CONCLUSION

Local drug delivery using chlorhexidine chip enhances the benefit of SRP in the treatment of chronic periodontitis.

Chlorhexidine chip in the treatment of chronic periodontitis - a clinical study

AIM

The aim of this study was to clinically evaluate the use of biodegradable chlorhexidine chip when used as an adjunct to scaling and root planing (SRP) in the treatment of moderate to severe periodontitis patients. The study also intended to compare the combined therapy (SRP and Chlorhexidine chip) with chlorhexidine chip alone in individuals with periodontitis.

MATERIALS AND METHODS

Fifteen patients with three sites having a probing depth of 5-8mm were considered for the study. Sites were numbered 1, 2, 3 randomly. The clinical parameters assessed were the Plaque Index (PI), gingival index (GI), Bleeding on probing (BOP), Clinical attachment level (CAL) and Probing pocket depth (PPD). Following baseline evaluation, on two sites scaling and root planing (SRP) was performed, no treatment was carried out in the third site. Chlorhexidine chips were placed on one site with SRP and another without SRP. A periodontal pack was placed on the site to prevent dislodgement of the CHX chip. Clinical parameters were recorded at baseline, one month and three months. Duration of the study was for three months.

STATISTICAL ANALYSIS

T-test and Analysis of variance (ANOVA) has been carried out in the present study.

RESULTS

All three groups presented with an improvement in the clinical parameters compared to baseline. There was no statistically significant difference between the SRP and SRP + CHIP group in all parameters. There was a significant difference when these two groups were compared to the chip alone group. The mean reductions in PPD were 2.8mm (SRP group), 2.6 (SRP+CHIP group), 0.8 (chip alone group) The mean gain in CAL were 2.8mm (SRP group), 2.5 (SRP+CHIP group), 0.7 (chip alone group). Reduction in bleeding on probing were significant for the SRP and SRP +CHIP group but not for the chip alone group.

CONCLUSION

The CHX chip did not provide any clinical benefit beyond that achieved with conventional scaling and rootplaning after a three month period.

In situ forming implants for periodontitis treatment with improved adhesive properties

Novel in situ forming implants are presented showing a promising potential to overcome one of the major practical hurdles associated with local periodontitis treatment: limited adhesion to the surrounding tissue, resulting in accidental expulsion of at least parts of the implants from the patients' pockets. This leads to high uncertainties in the systems' residence times at the site of action and in the resulting drug exposure. In the present study, the addition of different types and amounts of plasticizers (acetyltributyl citrate and dibutyl sebacate) as well as of adhesive polymers (e.g., cellulose derivatives such as hydroxypropyl methylcellulose) is shown to allow for a significant increase in the stickiness of poly(lactic-co-glycolic acid)-based implants. The systems are formed in situ from N-methyl pyrrolidone-based liquid formulations. Importantly, at the same time, good plastic deformability of the implants can be provided and desired drug release patterns can be fine-tuned using several formulation tools. The antimicrobial activity of this new type of in situ forming implants, loaded with doxycycline hyclate, was demonstrated using the agar well diffusion method and multiple Streptococcus strains isolated from the oral microflora of patients suffering from periodontitis.

Quantifying effects of interactions between polyacrylic acid and chlorhexidine in dicalcium phosphate – forming cements

Polyacrylic acid has been shown to control setting and improve mechanical and antibacterial release properties of brushite bone cements.

Drug-releasing implants: current progress, challenges and perspectives

This review presents the different types and concepts of drug-releasing implants using new nanomaterials and nanotechnology-based devices.

Efficacy of xanthan based chlorhexidine gel as an adjunct to scaling and root planing in treatment of the chronic periodontitis

Aim:

The aim of this study was to evaluate the clinical effectiveness of locally delivered xanthan-based Chlosite^® gel as an adjunctive therapy to scaling and root planing in treatment of chronic periodontitis.

Materials and Methods:

In a randomized controlled clinical study, 30 patients were selected. Pocket depth between 5 and 7 mm was selected and each patient had two sites on the same side of the mouth. A total of 30 control sites were scaled and root planed and 30 test sites were scaled and root planed and Chlosite^® gel was added. The clinical parameters, probing depth (PD), clinical attachment level (CAL), plaque index (PI) and bleeding on probing (BOP), gingival index were recorded at baseline, 6 weeks, 3 months and 6 months.

Statistical Analysis:

Paired/unpaired t-test was used, significance was placed at 5% level of significance, i.e., P < 0.05 was considered as a significant.

Results:

From baseline to a period of 6 months, significant difference was found between test and control group for PD, CAL, PI and BOP, P value being PD (P = 0.002), CAL index (P = 0.014), respectively.

Conclusion:

Subgingival injection of xanthan-based Chlosite^® gel adjunct with scaling and root planing appeared to cause significant improvement compared with scaling and root planing alone in persons with chronic periodontitis.

Comparison of the efficacy of chlorhexidine varnish and chip in the treatment of chronic periodontitis

BACKGROUND

The purpose of this study was to clinically evaluate the benefits of sub gingival chlorhexidine (CHX) varnish and biodegradable CHX chip application used as an adjunct to scaling and root planning (SRP) as combined therapy and also to compare the effect of combined therapy with SRP alone.

MATERIALS AND METHODS

Fifteen patients with at least three sites with a probing pocket depth (PPD) of 5-8 mm were considered. Following baseline evaluation, all three sites were subjected for SRP. After completing SRP, each site was randomly subjected for CHX varnish, CHX chip application and the 3(rd) site was left without any medication as a control. Clinical parameters such as sulcus bleeding index, plaque index, bleeding on probing (BOP), PPD, and clinical attachment level (CAL) were recorded at baseline, 1 month and 3 months post-operatively.

RESULTS

All three groups presented with an improvement in clinical parameters compared to baseline. The mean reduction in PPD was 2.4 mm in SRP sites, 2.5 mm in SRP + CHX varnish sites and 2.8 mm in SRP + CHX chip sites. The mean gain in CAL was 2.4 mm in SRP sites, 2.3 mm in SRP + CHX varnish sites and 2.8 mm SRP + CHX chip sites.

INTERPRETATION AND CONCLUSION

The present study indicated that application of CHX varnish and placement of CHX chip as an adjunct to SRP produced a clinically significant reduction in the PPD, BOP and a gain in CAL at 30(th) day and 90(th) day from baseline when compared to SRP alone. The results though were not statistically significant.

Effect of controlled-release Periochip™ on clinical and microbiological parameters in patients of chronic periodontitis

BACKGROUND

The aim of the present study was to evaluate and compare the clinical and microbiological effectiveness of Periochip™ as an adjunct to scaling and root planing (SRP) with SRP alone in patients with chronic periodontitis.

MATERIALS AND METHODS

This randomized, split mouth, 3-month clinical and microbiological trial included 30 sites in 15 patients aged 30-50 years diagnosed with chronic periodontitis. In each patient, two bilateral pockets probing 5-7 mm were randomly assigned to test and control groups. The test group received SRP plus Periochip™, whereas the control group received SRP alone. Clinical indices and anaerobic culture analysis was done at baseline, 1 month, and 3 months interval. Total bacterial count and analysis of four major periodontopathogenic bacteria Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Aggregatibacter actinomycetemcomitans (Aa), and Fusobacterium nucleatum (Fn) was done.

RESULTS

Significant improvement was obtained in all clinical variables in the test group as compared to the control group over the study period. Total colony counts were significantly reduced in the test group as compared to control over the period of time. At baseline Aa was recovered from 4 test group sites and 5 control group sites, Pg from 15 test group and 14 control group sites, Pi from 5 test group and 2 control group sites, Fn from 7 test and 7 control group sites. At 3 months, Aa was recovered from 1 test group and 4 control group sites, Pg from 4 test group and 8 control group sites, Pi from 1 test group and 1 control group site, Fn from 3 test and 4 control group sites.

CONCLUSION

Periochip™ placement as an adjunct to SRP, showed promising results, when compared to SRP alone. Healthy microflora can be maintained for a longer period of time and delay in the repopulation by periodontopathic microorganisms was observed.

A systematic review on the effects of local antimicrobials as adjuncts to subgingival debridement, compared with subgingival debridement alone, in the treatment of chronic periodontitis

AIMS

To update the existing scientific evidence on the efficacy of local antimicrobials as adjuncts to subgingival debridement in the treatment of chronic periodontitis.

MATERIAL AND METHODS

Fifty-six papers were selected, reporting data from 52 different investigations. All the studies reported changes in probing pocket depth (PPD) and clinical attachment level (CAL) and most in plaque index (PlI) and/or bleeding on probing (BOP). Meta-analyses were performed with the data retrieved from the studies fulfilling the inclusion criteria.

RESULTS

The overall effect of the subgingival application of antimicrobials was statistically significant (p = 0.000) for both changes in PPD and CAL with a weighted mean difference (WMD) of -0.407 and -0.310 mm respectively. No significant differences occurred for changes in BOP and PlI. Subgingival application of tetracycline fibres, sustained released doxycycline and minocycline demonstrated a significant benefit in PPD reduction (WMD between 0.5 and 0.7 mm). The rest of the tested outcomes demonstrated a high heterogeneity. The local application of chlorhexidine and metronidazole showed a minimal effect when compared with placebo (WMD between 0.1 and 0.4 mm).

CONCLUSIONS

The scientific evidence supports the adjunctive use of local antimicrobials to debridement in deep or recurrent periodontal sites, mostly when using vehicles with proven sustained release of the antimicrobial.

Multiple applications of flurbiprofen and chlorhexidine chips in patients with chronic periodontitis: a randomized, double blind, parallel, 2-arms clinical trial

AIM

The aim of the present randomized, double blind, parallel, 2-arm clinical study was to examine the safety and efficacy of frequent applications of chlorhexidine chip (CHX) and flurbiprofen chip (FBP) in patients with chronic periodontitis.

METHODS

Sixty patients were randomized into CHX and FBP groups. Following OHI and scaling and root planing (SRP), baseline pocket depth (PD) measurements, gingival recession and bleeding on probing (BOP) were performed and repeated at week 4 and 8. The assigned chip was placed at weeks 0, 1, 2, 3, 5, 7.

RESULTS

Mean PD reduction in the CHX group was 2.08 mm (7.17 to 5.09, p < 0.0001). Mean PD reduction in the FBP group was 2.27 mm (6.72 to 4.45, p < 0.0001). Ninety-seven percentage and 95% of these sites exhibited PD reduction ≥1 mm, while 38% and 34% of the sites exhibited PD ≥3 mm (FBP and CHX, respectively). Clinical attachment level gain (1.66 and 1.95 mm, respectively) was statistically significant (p < 0.0001). Baseline BOP dropped from 98% and 100% to 24% and 30% for the CHX and FBP groups, respectively (p < 0.0001).

CONCLUSION

Frequent applications of CHX and FBP chips resulted in a significant improvement in the periodontal condition in these sites. Furthermore studies will be required to compare this new treatment regimen to SRP or SRP with single chip application.

Single use of tetracycline with and without diclofenac sodium as local drug delivery in pocket therapy: a clinico-microbiological study

AIM

  Local drug delivery is a non-surgical method in the treatment of periodontitis. Different chemotherapeutic agents are used for local drug delivery; one such agent is tetracycline, a broad-spectrum antibiotic. Recent studies have also shown that the use of non-steroidal anti-inflammatory drugs reduces pro-inflammatory cytokines and acts as host modulator. Thus, an attempt was made to compare and evaluate the efficacy of tetracycline alone and in combination with diclofenac sodium as a local drug delivery.

METHODS

  A total of 36 sites with chronic periodontitis were divided into three groups with 12 sites each (i.e. group A, antibiotics alone; group B, antibiotics in combination with non-steroidal anti-inflammatory drugs; and group C, control group). For all the groups, the following parameters (plaque index, papillary bleeding index, probing pocket depth, and microbial analysis) were assessed and statistically analyzed.

RESULTS

  The antibiotic and non-steroidal anti-inflammatory drug combination group showed a statistically-significant improvement in clinical parameters and a shift in microbial flora when compared to the group with antibiotics alone. However, the control group failed to show any statistically-significant improvement.

CONCLUSION

  Antibiotics in combination with non-steroidal anti-inflammatory drugs are more efficient than using antibiotics alone as local drug delivery for the treatment of periodontal pockets.

Adsorption of chlorhexidine on synthetic hydroxyapatite and in vitro biological activity

The kinetic of chlorhexidine digluconate (CHXDG) uptake from aqueous solution by hydroxyapatite (HA) was investigated by ultraviolet (UV) analysis performed in HA powder (UV-solid) after the CHX adsorption. Adsorption isotherm of chlorhexidine (CHX) uptake was modeled by a combination of Languimir and Langmuir-Freundlich mechanisms. Strong molecule-molecule interactions and positive cooperativity predominated in the surface when CHX concentration was above 8.6 μg(CHX)/mg(HA). UV-solid spectra (shape, intensity and band position) of CHX bound to HA revealed that long-range molecular structures, such as aggregates or micelles, started to be formed at low CHX concentrations (1.52 μg(CHX)/mg(HA)) and predominated at high concentrations. Grazing-incidence X-ray diffraction (GIXRD) analysis from synchrotron radiation discarded the formation of crystalline structures on HA surface or precipitation of CHX crystalline salts, as suggested in previous works. The effect of the HA/CHX association on HA in vitro bioactivity, cytotoxicity and CHX antimicrobial activity was evaluated. It was shown that CHX did not inhibit the precipitation of a poorly crystalline apatite at HA/CHX surface after soaking in simulating body fluid (SBF). Cell viability studies after exposure to extracts of HA and HA/CHX showed that both biomaterials did not present significant in vitro toxicity. Moreover, HA/CHX inhibited Enterococcus faecalis growth for up to 6 days, revealing that binding to HA did not affect antimicrobial activity of CHX and reduced bacterial adhesion. These results suggested that HA/CHX association could result in a potential adjuvant antimicrobial system for clinical use.

Periodontitis: an archetypical biofilm disease

BACKGROUND

Periodontitis is a classic example of biofilm-mediated diseases.

METHODS

The authors reviewed selected publications in English-language peer-reviewed journals with respect to microbial biofilms, focusing on representative works that provided a historical to a contemporary perspective on periodontal oral biofilms in the larger context of biofilm microbiology.

RESULTS

Developments in advanced microscopy and molecular microbiology have allowed scientists to examine and characterize microbial biofilm-mediated diseases, such as periodontitis, more accurately than in the past.

CONCLUSIONS

Periodontitis, like other biofilm infections, is refractory to antibiotic agents and host defenses because the causative microbes live in complex communities that persist despite challenges that range from targeted antibiotic agents to phagocytosis.

CLINICAL IMPLICATIONS

The regular delivery of nontargeted antibiofilm agents may be an effective strategy for treating biofilms, especially if these agents include oxidative agents that dissolve the biofilm matrix.

Characterization of chlorhexidine-releasing, fast-setting, brushite bone cements

The effect of antibacterial chlorhexidine diacetate powder (CHX) on the setting kinetics of a brushite-forming beta-tricalcium phosphate/monocalcium phosphate monohydrate (beta-TCP/MCPM) cement was monitored using attenuated total reflection Fourier transform infrared spectroscopy. The final composition of the set cement with up to 12 wt.% CHX content before and after submersion in water for 24h, the kinetics of chlorhexidine release and the total sample mass change in water over four weeks was monitored using Raman mapping, UV spectroscopy and gravimetry, respectively. Below 9 wt.%, CHX content had no significant effect on brushite formation rate at 37 degrees C, but at 12 wt.% the half-life of the reaction decreased by one-third. Raman mapping confirmed that brushite was the main inorganic component of the set cements irrespective of CHX content, both before and after submersion in water. The CHX could be detected largely as discrete solid particles but could also be observed partially dispersed throughout the pores of the set cement. The percentage of CHX release was found to follow Fick's law of diffusion, being independent of its initial concentration, proportional to the square root of time and, with 1mm thick specimens, 60% was released at 24h. Total set cement mass loss rate was not significantly affected by CHX content. On average, cements exhibited a loss of 7 wt.% assigned largely to surface phosphate particle loss within the initial 8h followed by 0.36 wt.% per day.

Clinical Evaluation of the Use of Locally Delivered Chlorhexidine in Periodontal Maintenance Therapy

BACKGROUND

The objective of this study was to evaluate clinically the effectiveness of a chlorhexidine gluconate chip in sites still showing signs of disease during periodontal maintenance therapy.

METHODS

Forty-two maintenance non-smoking patients (previously treated with non-surgical scaling and root planing [SRP]), presenting at least one probing depth (PD) of 5 to 8 mm, and bleeding on probing (BOP) at single-rooted teeth were assigned randomly to two groups: treated with a chlorhexidine gluconate chip (CHIP group) and treated with SRP (SRP group). Patients were assessed for plaque index, gingival index, BOP, PD, clinical attachment level (CAL), and gingival recession at baseline, 6 weeks, and 3 and 6 months.

RESULTS

Both treatments resulted in improvements in all parameters evaluated. After 6 months, a reduction in PD of 2.64 +/- 0.02 mm and 2.12 +/- 0.02 mm was observed for CHIP and SRP groups, respectively (P >0.05). The observed gain in CAL was 2.19 +/- 0.87 mm and 2.07 +/- 1.53 mm for CHIP and SRP groups, respectively (P >0.05). In deep pockets, PD reduction was 3.60 +/- 0.70 mm for CHIP group and 2.83 +/- 0.62 mm for SRP group (P = 0.01).

CONCLUSIONS

Both treatments were equally effective in periodontal health reestablishment in inflamed single-root sites of maintenance patients. However, for deep pockets, the chlorhexidine gluconate chip was more effective than SRP in reducing PD.