Initial effect of controlled release chlorhexidine on subgingival microorganisms

Exploring the Potential of a Herbal Nanoemulsion as an Antimicrobial Mouthwash

The study aimed to formulate a nanoemulsion, combine it with aqueous extracts of herbal powders, and test its efficiency as caries-preventing mouthwash. Formulation of nanoemulsion using microfluidizer, characterization of nanoemulsion, minimum inhibitory concentration, adherence test, biofilm assay, and artificial mouth assay was carried out. The biofilms of Streptococcus mutans, Lactobacillus casei, Actinomyces viscosus, and a combination of the three cultures were developed and treated with formulations to study the inhibitory effect of the samples. In artificial mouth assay, human tooth samples were used as surfaces to grow the biofilm of S. mutans, and daily, the teeth were treated with the formulations to test their real-time efficiency. The nanoemulsion was characterized using dynamic light scattering and the size of the particles was within the 100-300 nm range. Above 50 °C, the nanoemulsion combined with plant extract lost its emulsified state within 2 h of incubation, while the nanoemulsion was stable. Nanoemulsion with plant extract inhibited the adherence of L. casei (73%) and biofilm of L. casei (66%). In artificial mouth assay, after 10 days of nanoemulsion, nanoemulsion with plant extract showed DIAGNOdent pen values 3.5 and 2 respectively whereas the negative control value was 14.4 indicating caries initiation. The nanoemulsion with plant extract showed anti-adherence and anti-biofilm activity and hence can be used as a potent anticariogenic mouthwash.

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.

Antimicrobial behavior of titanium coating with chlorhexidine-doped thin film exposed to a biofilm supplemented with nicotine

Because nicotine upregulates the growth of most oral bacteria, this in vitro study investigated the antimicrobial effect of chlorhexidine-doped thin film on commercially pure titanium against Fusobacterium nucleatum (F. nucleatum) biofilm supplemented with different concentrations of nicotine (0, 1, and 2 mg/mL). Biofilms were formed on a chlorhexidine-doped thin film on commercially-pure-titanium discs and compared to the control groups. Biofilm viability, total biofilm growth using a spectrophotometer, extracellular polysaccharide content, and pH variations were assessed as dependent variables. Data were submitted to ANOVA and Tukey honest significant difference tests (α=0.05). F. nucleatum biofilm growth was inhibited when exposed to chlorhexidine-doped thin film (p<0.05). Biofilm supplemented with nicotine did not impact the synthesis of EPS on the same type of treatment (p>0.05). The pH values were significantly increased with the increase of nicotine concentration (p<0.05). Chlorhexidine-doped thin film was effective in reducing F. nucleatum biofilm supplemented with nicotine.

Comparative Evaluation of Cost-Effectiveness, Clinical and Microbiological Parameters of Systemic Antibiotics Versus Local Drug Delivery in Aggressive Periodontitis

BACKGROUND

Periodontitis is a biofilm-associated inflammatory disease of the periodontium in which microbial component contributes to its initiation that mainly includes chronic periodontitis and aggressive periodontitis (AgP).

AIM

The present study aimed to ascertain a cost-effective treatment approach in AgP with minimal side effects by comparing systemic antibiotics (SA) and local drug delivery (LDD) as an adjunct to scaling and root planning (SRP). Furthermore, the objectives were to analyze its effect on clinical and microbial parameters.

MATERIALS AND METHODS

The participants were randomly divided into two groups A and B with eleven participants each. Group A was administered with Chlosite Gel [LDD] whereas group B with amoxicillin (AMX) 500 mg + metronidazole (MTZ) 400 mg [SA] thrice daily for 14 days. Clinical parameters such as plaque index (PI), gingival index (GI), clinical attachment level (CAL), and pocket probing depth (PPD)] were recorded at baseline and three months postoperatively. Microbiological parameters i.e Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) counts were also measured at baseline and after three months.

RESULTS

Statistically significant difference was observed in all clinical parameters i.e. PI, GI, CAL, and PPD after three months follow-up in groups A and B. Reduced bacterial load i.e. Aa and Pg was significant at three months in both the groups. However, on comparing the total expenditure of both the groups, group A ranged from 920-1480 ₹ while in group B it ranged from 330-360 ₹. Hence, lower expenditure in group B (3.7 fold) compared to group A was evident.

CONCLUSIONS

Cost-effective approach recommended in the present study is mainly to promote awareness among periodontal patients in the public and private sectors, who refuse to get dental treatment due to fear of high expenditure. This can be attained by incorporating SA as an alternative to LDD in AgP patients.

Nanotechnology-based therapies for the prevention and treatment of Streptococcus mutans-derived dental caries

BACKGROUND

Dental caries results from long-term acid production when sugar is metabolized by a bacterial biofilm, resulting in a loss of calcium and phosphate from the enamel. Streptococcus mutans is a type of acid-producing bacteria and a virulent contributor to oral biofilms. Conventional treatment options, such as cefazolin and ampicillin, have significant levels of bacterial resistance. Other topical agents, such as fluoride, tend to be washed away by saliva, resulting in low therapeutic efficacy.

HIGHLIGHT

This review aims to highlight the solubility issues that plague poorly water-soluble therapeutic agents, various novel polymeric, and lipid-based nanotechnology systems that aim to improve the retention of therapeutic agents in the oral cavity.

CONCLUSION

In this review, different formulation types demonstrated improved therapeutic outcomes by enhancing drug solubility, promoting penetration into the deep layers of the biofilm, facilitating prolonged residence time in the buccal cavity, and reducing the emergence of drug-resistant phenotypes. These formulations have a strong potential to give new life to therapeutic agents that have limited physicochemical characteristics.

Treatment of periodontal disease using xanthan based chlorhexidine gel

People of all ages are suffering from periodontal disease. It causes indirect damage in the oral cavity. It is of interest to evaluate the efficacy of xanthan-based chlorhexidine gel (Xan-CHX) in patients with mild-severe chronic periodontitis. Five patients with 60 sites were divided in two groups. Group A (treated with SRP) and group B (treated with Chlosite i.e., SRP + CHL). The recorded clinical parameters were Plaque index (PI), Gingival index (GI), Bleeding index (BI), and Clinical attachment Level (CAL) with sub gingival plaque subjected to microbial analysis. Significant reduction was observed in both groups. However, group B (treated with Chlosite i.e., SRP + CHL) showed statistically significant improvement on above mentioned parameters as compared to group A. Data suggest that in the treatment of periodontal disease (viz. PI, GI, BI and CAL) combination of SRP and Chlosite showed added benefits over only SRP.

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.

Synthesis of multifunctional chlorhexidine-doped thin films for titanium-based implant materials

Our goal was to create bio-functional chlorhexidine (CHX)-doped thin films on commercially pure titanium (cpTi) discs using the glow discharge plasma approach. Different plasma deposition times (50, 35 and 20 min) were used to create bio-functional surfaces based on silicon films with CHX that were compared to the control groups [no CHX and bulk cpTi surface (machined)]. Physico-chemical and biological characterizations included: 1. Morphology, roughness, elemental chemical composition, film thickness, contact angle and surface free energy; 2. CHX-release rate; 3. Antibacterial effect on Streptococcus sanguinis biofilms at 24, 48 and 72 h; 4. Cytotoxicity and metabolic activity using fibroblasts cell culture (NIH-F3T3 cells) at 1, 2, 3 and 4 days; 5. Protein expression by NIH-F3T3 cells at 1, 2, 3 and 4 days; and 6. Co-culture assay of fibroblasts cells and S. sanguinis to assess live and dead cells on the confocal laser scanning microscopy, mitochondrial activity (XTT), membrane leakage (LDH release), and metabolic activity (WST-1 assay) at 1, 2 and 3 days of co-incubation. Data analysis showed that silicon films, with or without CHX coated cpTi discs, increased surface wettability and free energy (p < 0.05) without affecting surface roughness. CHX release was maintained over a 22-day period and resulted in a significant inhibition of biofilm growth (p < 0.05) at 48 and 72 h of biofilm formation for 50 min and 20 min of plasma deposition time groups, respectively. In general, CHX treatment did not significantly affect NIH-F3T3 cell viability (p > 0.05), whereas cell metabolism (MTT assay) was affected by CHX, with the 35 min of plasma deposition time group displaying the lowest values as compared to bulk cpTi (p < 0.05). Moreover, data analysis showed that films, with or without CHX, significantly affected the expression profile of inflammatory cytokines, including IL-4, IL-6, IL-17, IFN-y and TNF-α by NIH-F3T3 cells (p < 0.05). Co-culture demonstrated that CHX-doped film did not affect the metabolic activity, cytotoxicity and viability of fibroblasts cells (p > 0.05). Altogether, the findings of the current study support the conclusion that silicon films added with CHX can be successfully created on titanium discs and have the potential to affect bacterial growth and inflammatory markers without affecting cell viability/proliferation rates.

Periodontitis: facts, fallacies and the future

This volume of Periodontology 2000 represents the 25th anniversary of the Journal, and uses the occasion to assess important advancements in periodontology over the past quarter-century as well as the hurdles that remain. Periodontitis is defined by pathologic loss of the periodontal ligament and alveolar bone. The disease involves complex dynamic interactions among active herpesviruses, specific bacterial pathogens and destructive immune responses. Periodontal diagnostics is currently based on clinical rather than etiologic criteria, and provides limited therapeutic guidance. Periodontal causative treatment consists of scaling, antiseptic rinses and occasionally systemic antibiotics, and surgical intervention has been de-emphasized, except perhaps for the most advanced types of periodontitis. Plastic surgical therapy includes soft-tissue grafting to cover exposed root surfaces and bone grafting to provide support for implants. Dental implants are used to replace severely diseased or missing teeth, but implant overuse is of concern. The utility of laser treatment for periodontitis remains unresolved. Host modulation and risk-factor modification therapies may benefit select patient groups. Patient self-care is a critical part of periodontal health care, and twice-weekly oral rinsing with 0.10-0.25% sodium hypochlorite constitutes a valuable adjunct to conventional anti-plaque and anti-gingivitis treatments. A link between periodontal herpesviruses and systemic diseases is a strong biological plausibility. In summary, research during the past 25 years has significantly changed our concepts of periodontitis pathobiology and has produced more-effective and less-costly therapeutic options.

Devices for In situ Development of Non-disturbed Oral Biofilm. A Systematic Review

Objective: The aim of this review was to assess the types of devices used for in situ development of oral biofilm analyzed microbiologically.

Materials and Methods: A systematic search of the literature was conducted to identify all in situ studies of oral biofilm which used an oral device; the Ovid MEDLINE and EMBASE databases complemented with manual search were used. Specific devices used to microbiologically analyze oral biofilm in adults were included. After reading of the selected full texts, devices were identified and classified according to the oral cavity zone and manufacturing material. The “ideal” characteristics were analyzed in every group.

Results: The search provided 787 abstracts, of which 111 papers were included. The devices used in these studies were classified as palatal, lingual or buccal. The last group was sub-classified in six groups based on the material of the device. Considering the analyzed characteristics, the thermoplastic devices and the Intraoral Device of Overlaid Disk-holding Splints (IDODS) presented more advantages than limitations.

Conclusions: Buccal devices were the most commonly used for the study of in situ biofilm. The majority of buccal devices seemed to slightly affect the volunteer's comfort, the IDODS being the closest to the “ideal” model.

Clinical Relevance: New devices for in situ oral biofilm microbiological studies should take into account the possible effect of their design on the volunteer's comfort and biofilm formation.

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.

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 substantivity on salivary flora and plaque-like biofilm: an in situ model

OBJECTIVE

To evaluate the in situ antibacterial activity of a mouthrinse with 0.2% Chlorhexidine (M-0.2% CHX) on undisturbed de novo plaque-like biofilm (PL-biofilm) and on salivary flora up to 7 hours after its application.

METHODS

A special acrylic appliance was designed, with 3 inserted glass disks on each buccal side, allowing for PL-biofilm growth. Fifteen healthy volunteers wore the appliance for 48 hours and then performed an M-0.2% CHX; disks were removed at 30 seconds and 1, 3, 5 and 7 hours after the mouth-rinsing. Applying a washout period, saliva samples were collected from each volunteer at 30 seconds and 1, 3, 5 and 7 hours after performing an M-0.2% CHX. The PL-biofilm and saliva samples were analysed by confocal laser scanning and epifluorescence microscopes, respectively.

RESULTS

At 30 seconds after M-0.2% CHX, the levels of viable bacteria detected in saliva were significantly lower than those observed in PL-biofilm. The difference in the percentage of live bacteria detected in saliva was significantly higher than that observed in PL-biofilm at 5 and 7 hours after M-0.2% CHX.

CONCLUSION

After a single mouthrinse of the 0.2% CHX formulation tested in the present study, the 2-day PL-biofilm presented a significantly higher resistance to this antiseptic in situ than that observed in salivary flora. However, this 0.2% CHX formulation showed a higher substantivity on PL-biofilm than on salivary flora at 5 and 7 hours after mouth-rinsing, which could be related to the slower growth rate of PL-biofilm and the possible reservoir function for antimicrobial agents associated with the undisturbed de novo PL-biofilm.

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.

Low-cost periodontal therapy

Periodontitis is a complex infectious disease that affects low-income individuals disproportionately. Periodontitis is associated with specific bacterial species and herpesviruses, and successful prevention and treatment of the disease is contingent upon effective control of these pathogens. This article presents an efficacious, highly safe, minimally invasive, practical and low-cost periodontal therapy that involves professional and patient-administered mechanical therapy and antimicrobial agents. The major components are scaling for calculus removal, periodontal pocket irrigation with potent antiseptics, and treatment with systemic antibiotics for advanced disease. Povidone-iodine and sodium hypochlorite have all the characteristics for becoming the first-choice antiseptics in the management of periodontal diseases. Both agents show excellent antibacterial and antiviral properties, are readily available throughout the world, have been safely used in periodontal therapy for decades, offer significant benefits for individuals with very limited financial resources, and are well accepted by most dental professionals and patients. Four per cent chlorhexidine applied with a toothbrush to the most posterior part to the tongue dorsum can markedly reduce or eliminate halitosis in most individuals. Systemic antibiotics are used to treat periodontopathic bacteria that are not readily reached by topical therapy, such as pathogens within gingival tissue, within furcation defects, at the base of periodontal pockets, and on the tongue, tonsils and buccal mucosae. Valuable antibiotic therapies are amoxicillin-metronidazole (250 mg of amoxicillin and 250 mg of metronidazole, three times daily for 8 days) for young and middle-aged patients, and ciprofloxacin-metronidazole (500 mg of each, twice daily for 8 days) for elderly patients and for patients in developing countries who frequently harbor enteric rods subgingivally. Scaling to remove dental calculus and the prudent use of inexpensive antimicrobial agents can significantly retard or arrest progressive periodontitis in the great majority of patients.

Effect of insertion of xanthan-based chlorhexidine gel in the maintenance phase following the treatment of chronic periodontitis

OBJECTIVES

The aim of this study was to evaluate the efficacy of subgingivally administered xanthan-based chlorhexidine gel when used in the maintenance phase following scaling and root planing (SRP) in the treatment of chronic periodontitis.

MATERIALS AND METHODS

A randomized, controlled, single-center study was conducted involving 92 sites in 46 systemically healthy patients suffering from moderate to advanced chronic periodontitis with isolated pockets. The selected sites were randomized to two treatment arms: Group A (SRP alone) and Group B (SRP + insertion of chlorhexidine gel after 1 month). The gingival index, plaque index, probing pocket depth (PPD) and clinical attachment level (CAL) were recorded at baseline and subsequently after 1 month and 3 months.

RESULTS

Both the groups showed significant reductions in PPD and CAL at both follow-up visits when compared with the baseline values (P<0.001).

CONCLUSIONS

The results suggest that the application of xanthan based chlorhexidine gel following SRP in the maintenance phase might be beneficial in treatment of the chronic periodontitis in comparison to SRP alone. Greater improvements may be achieved when antimicrobial agents are used following SRP.

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.

The comparative evaluation of xanthan gel with chlorhexidine (Chlosite) in smokers and non-smokers: A clinical and microbiological assessment

BACKGROUND AND OBJECTIVES

Prevention of the periodontal disease progression is the primary goal of periodontal therapy. When conventional therapy is found inadequate to attain periodontal health in chronic periodontitis, local antimicrobial agents have been used as an adjunct with scaling and root planning (SRP) which has reproduced encouraging results. Hence, this study was undertaken to evaluate the new sustained released local drug Chlosite clinically and microbiologically in smokers and non-smokers.

MATERIALS AND METHODS

The patients were grouped into experimental group A treated with SRP plus Chlosite (SRP + CHL), experimental group B treated with Chlosite alone (CHL), and control group C treated only with SRP alone. A total number of 141 sites from six patients (67 sites from three non-smoker patients and 74 sites from three smoker patients) participated in this study. The clinical parameters, Plaque index (PI), Gingival index (GI), Bleeding index (BI), and Relative attachment level (RAL), were recorded and subgingival plaque samples were collected and subjected to microbiological analysis.

RESULTS

On comparison of smokers and non-smokers, in SRP group, non-smokers showed a higher reduction in BI and GI and smokers showed a higher reduction in PI. There was no significant gain in RAL of both smokers and non-smokers. In SRP + CHL group, non-smokers showed a higher reduction in relation to BI and GI and smokers showed a higher reduction in relation to PI. There was no significant gain in RAL of both smokers and non-smokers. In CHL group, both smokers and non-smokers showed a nonsignificant reduction in BI, GI, and RAL, but smokers showed a significant reduction in PI as compared with non-smokers. All the groups showed reduction in the microbial count of Fusobacterium nucleatum, Porphyromonas gingivalis, and Tannerella forsythia which were found to be statistically not significant when it was compared between non-smokers and smokers.

INTERPRETATION AND CONCLUSION

In this study, all treatment groups were found to be efficacious in the treatment of periodontal disease as demonstrated by improvement in PI, GI, BI, and RAL. Combination of SRP and Chlosite resulted in added benefits compared with the two treatment groups.

Antimicrobial activity of nanoemulsion on cariogenic Streptococcus mutans

OBJECTIVE

To assess antimicrobial activities of nanoemulsion (NE) to control the adhesion and biofilm formation by Streptococcus mutans by in vitro.

DESIGN

In vitro antimicrobial susceptibility of nanoemulsion was determined as per National Committee for Clinical Laboratory Standards guidelines and agar diffusion, serial dilution technique for the determination of minimum inhibitory concentration and minimum bactericidal concentration (MIC/MBC). Efficacy was tested by kinetics of killing, biofilm assay and scanning electron microscopy.

RESULTS

: NE concentrations ranging from 1:100 to 1:10,000 dilutions were effective against S. mutans as shown through MIC/MBC assays. NE showed antimicrobial activity against planktonic cells at high dilutions, confirmed by time kill studies. 4-day-old S. mutans biofilms were treated with NE; subsequent reductions of bacterial cell counts were noticed with decreasing dilutions. Staining of NE-treated biofilms with LIVE/DEAD BacLight resulted in dead cell areas of up to 48% in 1 min, 84% at 1h and significant (<0.05) increases in dead cell counts at all time points. Damage to cell membranes and cell walls of S. mutans by NE was demonstrated using scanning electron microscopy (SEM).

CONCLUSION

These results suggest that nanoemulsion has effective antibacterial activity against S. mutans and may be a useful medication in the prevention of dental caries.

A novel approach to the use of subgingival controlled-release chlorhexidine delivery in chronic periodontitis: a randomized clinical trial

BACKGROUND

We aimed to analyze clinical, microbiologic, and serologic effects of chlorhexidine (CHX) chips used as a subgingival controlled-release delivery device before and immediately after scaling and root planing (SRP).

METHODS

Twenty-four patients presenting with ≥12 teeth with probing depth (PD) ≥5 mm and bleeding on probing were assigned in test or control groups. After prophylaxis, CHX chips (test) or placebo chips (control) were placed in pockets with PD ≥5 mm. Ten days later, SRP was performed in all teeth with PD ≥4 mm in a single appointment. Immediately after SRP, new chips were inserted in all pockets with PD ≥5 mm. Parameters were assessed at baseline; beginning of SRP; and 1, 3, and 6 months after treatment. Subgingival samples were obtained at baseline; beginning of SRP; and at 1 month after treatment. Periodontal pathogens Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola were analyzed. Serum levels of high sensitive C-reactive and lipopolysaccharide-binding proteins were measured. The changes of the parameters between and within the groups were tested by Mann-Whitney U test (P <0.05).

RESULTS

All clinical and serologic parameters improved in both groups over time. There was a significant difference in clinical attachment level (CAL) gain from baseline to 6 months between groups (1.17 mm in the test group versus 0.79 mm in the placebo group) (P <0.05). The treatment with CHX chips showed a greater reduction of the microorganisms of the "red complex" after 1 month (P = 0.02).

CONCLUSION

The use of CHX chips before and immediately after SRP improved CAL and reduced the subgingival microorganisms of the red complex in the treatment of chronic periodontitis.

Biological effects of a root conditioning agent for dentin surface modification in vitro

Purpose

Connective tissue reattachment to periodontally damaged root surfaces is one of the most important goals of periodontal therapy. The aim of this study was to develop a root conditioning agent that can demineralize and detoxify the infected root surface.

Methods

Dentin slices obtained from human teeth were treated with a novel root planing agent for 2 minutes and then washed with phosphate-buffered saline. Smear layer removal and type I collagen exposure were observed by scanning electron microscopy (SEM) and type I collagen immunostaining, respectively. Cell attachment and lipopolysaccharides (LPS) removal demonstrated the efficiency of the root conditioning agent.

Results

SEM revealed that the smear layer was entirely removed and the dentinal tubules were opened by the experimental gel. Type I collagen was exposed on the surfaces of the dentin slices treated by the experimental gel, which were compared with dentin treated with other root planing agents. Dentin slices treated with the experimental gel showed the highest number of attached fibroblasts and flattened cell morphology. The agar diffusion assay demonstrated that the experimental gel also has effective antimicrobial activity. Escherichia coli LPS were effectively removed from well plates by the experimental gel.

Conclusions

These results demonstrated that this experimental gel is a useful tool for root conditioning of infected root surfaces and can also be applied for detoxification of ailing implant surface threads.

Biomaterial and antibiotic strategies for peri-implantitis: a review

Dental implants have 89% plus survival rates at 10-15 years, but peri-implantitis or dental implant infections may be as high as 14%. Peri-implantitis can limit clinical success and impose health and financial burdens to patients and health providers. The pathogenic species associated with periodontitis (e.g., Fusobacterium ssp, A. actinomycetemcomitans, P. gingivalis) are also associated with peri-implantitis. Incidence of peri-implantitis is highest within the first 12 months after implantation, and is higher in patients who smoke or have poor oral health as well as with calcium-phosphate-coated or surface-roughened implants. Biomaterial therapies using fibers, gels, and beads to deliver antibiotics have been used in the treatment of Peri-implantitis though clinical efficacy is not well documented. Guided tissue regeneration membranes (e.g., collagen, poly-lactic/glycolic acid, chitosan, ePTFE) loaded with antimicrobials have shown success in reosseointegrating infected implants in animal models but have not been proven in humans. Experimental approaches include the development of anti-bioadhesion coatings, coating surfaces with antimicrobial agents (e.g., vancomycin, Ag, Zn) or antimicrobial releasing coatings (e.g., calcium phosphate, polylactic acid, chitosan). Future strategies include the development of surfaces that become antibacterial in response to infection, and improvements in the permucosal seal. Research is still needed to identify strategies to prevent bacterial attachment and enhance normal cell/tissue attachment to implant surfaces.

The inhibitory effects of naringin on the growth of periodontal pathogens in vitro

Naringin is a flavonoid that is commonly found in grapefruits. The objective of this study was to evaluate the effects of naringin on the growth of periodontal pathogens such as A. actinomycetemcomitans and P. gingivalis in vitro. For comparison, the effects of naringin on several oral microbes were also studied. Different concentrations of naringin solution were added to calibrated suspensions of A. actinomycetemcomitans and P. gingivalis. All the suspensions were incubated for 3, 6 and 24 h in an anaerobic chamber at 37 degrees C. At each time point, selected dilutions from each culture broth were plated on blood agar plates. Colonies recovered on blood agar were visually counted on days 3 and 5, respectively. A. actinomycetemcomitans showed a significant decrease (p < 0.05) in viable counts after 3 h when naringin was added at baseline. P. gingivalis also showed a marked growth reduction in the presence of naringin, and no colony forming units could be observed after 24 h. Naringin also had an inhibitory effect against all bacteria and yeasts tested. The results suggest that naringin possesses significant antimicrobial properties on periodontal pathogens in vitro. It also has an inhibitory effect on some common oral microorganisms in low concentrations.

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.

Controlled-delivery chlorhexidine chip versus amoxicillin/metronidazole as adjunctive antimicrobial therapy for generalized aggressive periodontitis: a randomized controlled clinical trial

BACKGROUND

Subgingival application of chlorhexidine via a controlled-delivery device (CHX chip) improves the clinical outcome of scaling/root planing (SRP) in therapy for chronic periodontitis. Generalized aggressive periodontitis (GAP) is commonly treated with SRP and adjunctive antimicrobial medication. To date, the efficacy of CHX chips in GAP therapy has not been evaluated.

AIM

To compare SRP plus adjunctive CHX chip placement with SRP plus adjunctive systemic amoxicillin/metronidazole with regard to clinical efficacy in first-line therapy for GAP.

MATERIAL AND METHODS

Thirty-six GAP patients were treated with SRP and randomly with either placement of CHX chips or systemic amoxicillin/metronidazole. Clinical attachment level (CAL), probing depth (PD), bleeding on probing (BoP) and suppuration (Pus) were measured at baseline, 3 and 6 months after therapy.

RESULTS

CAL, PD, BoP and Pus were significantly reduced in both groups after 3 months. In the CHX chip group, PD significantly increased again between 3 and 6 months. Finally, amoxicillin/metronidazole patients presented significantly more CAL "gain", PD reduction and less remaining deep sites after 6 months. Pus remained detectable in CHX chip patients only.

CONCLUSIONS

In first-line non-surgical therapy for GAP, SRP plus adjunctive systemic amoxicillin/metronidazole was more efficacious in clinically relevant measures of outcome than SRP plus adjunctive placement of CHX chips.

Effects of EDTA Gel Preconditioning of Periodontally Affected Human Root Surfaces on Chlorhexidine Substantivity – An SEM Study

BACKGROUND

Infection control is an important requirement during the early stages of periodontal healing. This study was performed to assess the preconditioning effect of EDTA gel on chlorhexidine (CHX) substantivity to periodontally involved root surfaces.

METHODS

Eighty patients with severe chronic periodontitis were enrolled in this study. Following cause-related therapy, patients were divided randomly into four groups. Each group consisted of 20 subjects with one tooth that was diagnosed as hopeless and designated for extraction. In group 1 (G1), selected periodontal pockets were filled with a placebo gel in a silica base for 2 minutes. Exposed roots in group 2 (G2) were etched for 2 minutes with a neutral EDTA conditioning agent, followed by pocket fill with the placebo gel. Pockets in group 3 (G3) were filled with 0.12% CHX digluconate gel in a silica base. Exposed roots in group 4 (G4) were etched for 2 minutes with a neutral EDTA conditioning agent, followed by pocket fill with the CHX gel. Four teeth from each group were extracted immediately and at 3, 12, 24, and 48 hours for SEM evaluation.

RESULTS

G1 and G2 specimens showed no evidence of silica adherent to any of the examined root surfaces. At 3 hours following CHX gel application, G3 specimens showed marked reduction in CHX-coated silica. At 24 and 48 hours following EDTA and CHX gel application, G4 specimens demonstrated adherent CHX-coated silica particles despite the reclogging of the tubule orifices.

CONCLUSION

EDTA and CHX gel root conditioning is a valuable regimen that improves CHX substantivity to periodontally involved root surfaces.

Effect of a Controlled-Release Chlorhexidine Chip on Clinical and Microbiological Parameters and Prostaglandin E2Levels in Gingival Crevicular Fluid

BACKGROUND

The aim of the present study was to determine the effect of a chlorhexidine chip on crevicular prostaglandin E2 (PGE2) levels and on the clinical and microbiological parameters of periodontitis when used as adjunctive therapy to scaling and root planing (SRP) in patients with chronic periodontitis.

METHODS

This randomized single-blind study was carried out in parallel design. The test group received SRP plus chlorhexidine chip, whereas the control group received SRP alone. Thirty-four subjects, aged 20 to 55 years, with chronic periodontitis were recruited. Clinical indices, microbiological samples, and gingival crevicular fluid (GCF) samples were evaluated at baseline and after 1, 3, and 6 months. Microbiological samples were evaluated under a light microscope. GCF PGE2 levels were determined using radioimmunoassay.

RESULTS

Significant improvements could be found for all clinical variables in both groups over the study period. The mean changes in probing depth obtained by SRP plus chlorhexidine chip were greater than those obtained by the SRP alone group at 3 and 6 months. In the test group, there was also significant gain in clinical attachment level at 6 months. When data were combined from all groups, significant reductions in GCF PGE2 levels and number of microorganisms were noted at all time points. However, in the test group, reduction was greater at 6 months for crevicular PGE2 level and at 3 and 6 months for proportions of spirochetes.

CONCLUSION

Based on the findings of this study, the chlorhexidine chip reduced GCF PGE2 levels and had positive effects on clinical parameters and subgingival flora when used as adjunctive therapy to SRP in patients with chronic periodontitis.

A Systematic Review on the Effects of the Chlorhexidine Chip When Used as an Adjunct to Scaling and Root Planing in the Treatment of Chronic Periodontitis

BACKGROUND

Several local antimicrobial agents, such as a bioabsorbable chlorhexidine chip, have been developed to enhance the outcome of non-surgical periodontal therapy.

METHODS

Electronic (MEDLINE and Cochrane Oral Health Group Specialized Trials Register) and manual searches were performed to detect studies concerning the use of the chlorhexidine chip as an adjunct to scaling and root planing in the treatment of chronic periodontitis. Only full-text randomized controlled trials published in English up to June 2005 were included.

RESULTS

Five studies were finally selected following independent screening by two reviewers. Due to considerable heterogeneity in study design, a qualitative data analysis was performed. Multicenter studies have indicated significantly higher pocket reductions and clinical attachment gains following a combination of mechanical debridement and repeated chlorhexidine chip administration in comparison to scaling and root planing alone. However, some recent studies failed to confirm the additional value of the chlorhexidine chip. A number of interstudy disparities with respect to methodological quality and study design may account for this lack of accordance.

CONCLUSIONS

The clinical and microbiological data currently available on the chlorhexidine chip are limited and conflicting. More research is needed to elucidate the additional value of the chlorhexidine chip when used as an adjunct to scaling and root planing.

A chlorhexidine varnish implemented treatment strategy for chronic periodontitis. Short-term clinical observations

OBJECTIVES

The aim of this study was to investigate the clinical outcome of a subgingivally applied chlorhexidine varnish when used as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis.

MATERIAL AND METHODS

A randomized controlled, single blind, parallel trial was conducted on the basis of 16 volunteers suffering from chronic periodontitis. The control group received oral hygiene instructions and was scaled and root planed in two sessions. The test group received the same instructions and treatment, however, all pockets were additionally disinfected using a chlorhexidine varnish. The gingival index, plaque index, bleeding on probing, probing pocket depth (PPD) and clinical attachment level (CAL) were recorded at baseline and subsequently after 1 and 3 months.

RESULTS

Both treatment strategies showed significant reductions in PPD and CAL at both follow-up visits by comparison with baseline levels (p<0.001). Yet, at study termination, combination therapy resulted in additional pocket reductions between 0.73 and 1.23 mm (p<0.02), and clinical attachment gains between 0.63 and 1.09 mm (p<0.02).

CONCLUSIONS

These findings suggest that a varnish-implemented strategy may improve the clinical outcome for the treatment of chronic periodontitis in comparison with SRP alone.

Isopanduratin A from Kaempferia pandurata as an active antibacterial agent against cariogenic Streptococcus mutans

An antibacterial compound active against Streptococcus mutans was isolated from Kaempferia pandurata and identified as isopanduratin A using 1H NMR, 13C NMR and EI-MS. The minimum inhibitory concentration (MIC) of isopanduratin A was 4 mg/l which was much lower than that of some other natural anticariogenic agents such as sanguinarine (12 mg/l), green tea extract and carvacrol (125 mg/l), thymol (250 mg/l) and isoeugenol and eucalyptol (500 mg/l). The bactericidal test showed that isopanduratin A completely inactivated S. mutans at 20 mg/l in 1 min. Significant inhibitory activity of isopanduratin A was also observed against S. sobrinus, S. sanguinis and S. salivarius with an MIC of 4 mg/l. Damage to the cell membrane and cell wall of S. mutans by isopanduratin A was shown using transmission electron microscopy (TEM). These results suggest that isopanduratin A could be employed as a potential antibacterial agent for preventing dental caries.

Antimicrobials for the treatment of aggressive periodontitis

Aggressive periodontitis is characterized by a considerable attachment loss over a relatively short period of time. It may be the consequence of either the presence of highly aggressive pathogens or a highly susceptible host. In the first case, the use of antimicrobials should be beneficial in the treatment of those patients. However, due to the organization of the micro-organisms as a biofilm, the increasing incidence of allergies and resistance against antimicrobials and their side-effects, there is still controversy about their benefit in the treatment of periodontal disease. This paper discusses indications for the use of antimicrobials, the substances prescribed and the type of application under the conditions of aggressive periodontitis.

Povidone-iodine as a periodontal pocket disinfectant

OBJECTIVES AND BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Selection of antimicrobial agents in periodontal therapy

BACKGROUND

The recognition over the past 3 decades of microbial specificity in periodontitis has afforded dental practitioners the ability to prevent and treat the disease with a variety of antimicrobial drugs. These include systemic antibiotics, topical antibiotics and topical antiseptics.

RESULTS

Systemic antibiotic therapy can be essential in eliminating pathogenic bacteria that invade gingival tissue and in helping control periodontal pathogens residing in various domains of the mouth from where they may translocate to periodontal sites. Frequently used periodontal combination antibiotic therapies are metronidazole-amoxicillin (250-375 mg of each 3 x daily for 8 days) and metronidazole-ciprofloxacin (500 mg of each 2 x daily for 8 days). Microbiological analysis helps determine the optimal antibiotic therapy and effectiveness of treatment. Topical antibiotics that are commercially available as controlled release devices suffer from several potential problems, including insufficient spectrum of antimicrobial activity in some periodontal polymicrobial infections, risks of producing an antibiotic resistant microbiota, and high acquisition costs. Topical antiseptics of relevance in periodontal treatment include 10% povidone-iodine placed subgingivally by a syringe for 5 min, and 0.1% sodium hypochlorite solution applied subgingivally by patients using an irrigation device.

CLINICAL IMPLICATIONS

The present paper recommends periodontal treatment that includes a battery of professionally and patient-administered antimicrobial agents (properly prescribed systemic antibiotics, povidone-iodine and sodium hypochlorite subgingival irrigants, and chlorhexidine mouthrinse). Available chemotherapeutics can provide effective, safe, practical and affordable means of controlling subgingival colonization of periodontal pathogens and various types of periodontal disease.