Non-surgical chemotherapeutic treatment strategies for the management of periodontal diseases. Dent Clin North Am. 2010;54:13-33. [PMID: 20103470 DOI: 10.1016/j.cden.2009.08.010]

Fabrication and Characterization of Electrospun Ocimum sanctum and Curcumin-Loaded Nanofiber Membrane for the Management of Periodontal Disease: An In Vitro Study

Background Periodontal disease is a chronic inflammatory condition that gradually deteriorates the supportive tissues of teeth, eventually leading to tooth loss. Mechanical debridement stands as the gold standard method for treating periodontitis. However, antimicrobial therapy is recommended for optimal results when used alongside mechanical debridement. Numerous studies have investigated local drug delivery as an adjunct to mechanical debridement of affected tooth surfaces. Ocimum sanctum exhibits anti-inflammatory, antioxidant, and antimicrobial properties. Similarly, curcumin, as documented in the literature, demonstrates a broad spectrum of anti-inflammatory and antimicrobial effects. Electrospinning has demonstrated itself to be a highly effective method for fabricating drug-loaded fibers. Electrospun nanofibers containing Ocimum sanctum and curcumin are expected to exhibit greater efficacy due to their increased surface area, facilitating the dispersion of larger quantities of drugs, and their ability to control drug release when employed as a local drug delivery system. This study aims to fabricate and characterize the properties of nanofiber membranes loaded with Ocimum sanctum and curcumin using the electrospinning technique. Methods About 50 mg each of Ocimum sanctum and curcumin were blended with 15% polyvinyl alcohol and 2% chitosan polymer in a 4:1 ratio and left to stir overnight. A 10 mL syringe was filled with this solution, and an 18 G blunt-end needle charged at 15.9 kV was used for extrusion. Continuous fibers were collected onto a collector plate positioned 12 cm from the center of the needle tip, at a flow rate of 0.005 mL/min. The morphology of the fabricated membrane was assessed through scanning electron microscopy (SEM), the strength of the material was assessed through tensile strength analysis using INSTRON, an Electropuls E3000 Universal Testing Machine (INSTRON, Norwood, MA), and the drug release pattern was analyzed using Jasco V-730 UV-visible spectrophotometer (Jasco, Easton, MD). Results The morphology of this nanofiber showed a random distribution of fibers with no bead formation. The average diameter of the membrane was 383±102 nm, and the tensile strength of this material was 1.87 MPa. The drug release pattern showed an initial burst release of Ocimum sanctum, followed by a controlled release in subsequent hours. However, curcumin showed very little drug release because of its solubility. Conclusion In summary, the Ocimum sanctum and curcumin-loaded nanofibers exhibited robust tensile strength, a controlled drug release profile, and uniform drug distribution within the nanofiber membrane. Consequently, it can be concluded that curcumin nanofibers and electrospun Ocimum sanctum serve as valuable agents for local drug delivery in the treatment of periodontitis.

Effect of preoperative chlorhexidine, essential oil, and cetylpyridinium chloride mouthwashes on bacterial contamination during dental implant surgery: A randomized controlled clinical trial

Background

Although the role of chlorhexidine and other mouthwashes in periodontal therapy has been elucidated, little information is available on their use as routine preoperative mouth rinses before surgery, especially in periodontal procedures such as dental implant surgery.

Objective

This study aimed to compare the efficacy of preoperative chlorhexidine, essential oil, and cetylpyridinium chloride mouthwashes in reducing bacterial contamination at the time of implant placement.

Materials and Methods

Eligible patients who underwent dental implant surgery were randomly divided into four groups based on the mouthwash used: (1) 0.12 % chlorhexidine, (2) essential oil, (3) cetylpyridinium chloride, and (4) saline (served as the control group). All the patients of each group rinsed preoperatively with 15 mL of the respective mouthwash for 60 s. Saliva samples before (pre) and immediately after rinsing with the mouthwash (post) and after suturing the flap (end) were collected on the day of the implant placement. Real-time quantitative polymerase chain reaction (qPCR) was performed to analyze the samples and quantify the targeted periodontal pathogens using a propidium monoazide (PMA) dye.

Results

Forty patients were included in the study. Real-time qPCR demonstrated a significant reduction in the number of pathogens in the saliva samples of the mouthwash groups compared to that of the control group. A statistically significant difference was observed between the groups for the pre-post and pre-end samples (p < 0.001) but not for the post-end samples (p = 0.203). A statistically significant difference was observed between the chlorhexidine, essential oil, and cetylpyridinium chloride mouthwash groups and the saline group (P < 0.001). The bacterial counts significantly differed with and without the use of the PMA dye.

Conclusions

Preoperative chlorhexidine, essential oil, and cetylpyridinium chloride mouthwashes can reduce the bacterial load at the time of implant placement, thereby reducing the incidence of implant-related complications.

Periodontal disease in down syndrome: Predisposing factors and potential non-surgical therapeutic approaches

BACKGROUND

Periodontal diseases (PDs) have been documented to be significantly more prevalent and severe in patients with Down syndrome (DS). Different immunological and microbiological factors contributed to predisposing these patients to progressive and recurrent PDs.

AIM

The aim of this review was to investigate the altered immunological responses and oral microbiota disorders as well as focus on adjunctive non-surgical methods for the treatment of PDs and its applicability in patients with DS.

MATERIAL AND METHODS

A literature review was conducted addressing the following topics: (1) the altered immunological responses, (2) orofacial disorders related to DS patients, (3) oral microbiota changing, and (4) adjunctive non-surgical treatment and its efficacy in patients with DS.

RESULTS

Due to the early onset of PDs in children with DS, the need for prompt and effective treatment in these patients is essential.

DISCUSSION AND CONCLUSION

So, investigating underlying factors may open a new window to better understand the pathology of PDs in DS people and thus, find better strategies for treatment in such group. Although non-surgical treatments such as photodynamic therapy and probiotic consumption represented acceptable outcomes in different examined patients without DS, data about the application of these convenience and no need for local anesthesia methods in patients with DS is limited.

Review on PLGA Polymer Based Nanoparticles with Antimicrobial Properties and Their Application in Various Medical Conditions or Infections

The rise in the resistance to antibiotics is due to their inappropriate use and the use of a broad spectrum of antibiotics. This has also contributed to the development of multidrug-resistant microorganisms, and due to the unavailability of suitable new drugs for treatments, it is difficult to control. Hence, there is a need for the development of new novel, target-specific antimicrobials. Nanotechnology, involving the synthesis of nanoparticles, may be one of the best options, as it can be manipulated by using physicochemical properties to develop intelligent NPs with desired properties. NPs, because of their unique properties, can deliver drugs to specific targets and release them in a sustained fashion. The chance of developing resistance is very low. Polymeric nanoparticles are solid colloids synthesized using either natural or synthetic polymers. These polymers are used as carriers of drugs to deliver them to the targets. NPs, synthesized using poly-lactic acid (PLA) or the copolymer of lactic and glycolic acid (PLGA), are used in the delivery of controlled drug release, as they are biodegradable, biocompatible and have been approved by the USFDA. In this article, we will be reviewing the synthesis of PLGA-based nanoparticles encapsulated or loaded with antibiotics, natural products, or metal ions and their antibacterial potential in various medical applications.

Probiotic Bifidobacteria in Managing Periodontal Disease: A Systematic Review

Although various probiotic organisms have been evaluated for their utility in the management of periodontitis, their strain-specific mechanisms of action are still unclear. We aimed to systematically review the effect of bifidobacterial probiotics on periodontopathogens and host immune responses in periodontal diseases. An electronic search of articles published until June 2022 in Medline, PubMed, Web of Science, and Cochrane Library databases was performed. Randomised controlled trials (RCTs) and in vitro and animal studies were assessed, and the data regarding antimicrobial properties, immunomodulation, and clinical outcomes were analysed. A total of 304 studies were screened, but only 3 RCTs and 6 animal and in vitro studies met the inclusion criteria. The use of different strains of bifidobacteria led to (1) a reduction of key players of the red complex periodontopathogens; (2) reduced levels of pro-inflammatory cytokines (eg, interleukin [IL]1-β and IL-8) and higher levels of anti-inflammatory cytokines (IL-10); (3) enhanced levels of osteoprotegerin and reduced levels of receptor activator of nuclear factor kappa-B ligand; and (4) a reduction of the dental plaque, bleeding on probing, alveolar bone loss, and clinical attachment loss. Bifidobacterial probiotic adjuvant supplementation, especially with Bifidobacterium animalis subspecies lactis, appears to help improve clinical periodontal parameters and develop a healthy plaque microbiome through microbiological and immunomodulatory pathways. Further human and animal studies are warranted prior to the therapeutic use of bifidobacteria in the routine management of periodontal infections.

Porphyromonas Gingivalis in the Development of Periodontitis: Impact on Dysbiosis and Inflammation

Chronic periodontitis is an inflammatory disease of the dental plaque and affects the soft tissues supporting the tooth. It is one of the most practical oral health issues across the globe and adversely affects the quality of life. In a neutrophil-mediated action, the inflammatory response to periodontitis destroys the periodontal ligaments, gums, the alveolar bone, and the cementum. Some of the most associated invasive pathogens with periodontitis are Porphyromonas Gingivalis, Aggregatibacter actinomycetecomitans, and Fusobacterium nucleatum. Google Scholar and PubMed were used to search the evidence using key terms like 'periodontitis,' 'Porphyromonas Gingivalis,' 'Oral Dysbiosis and Periodontitis,' 'Porphyromonas Gingivalis and Periodontitis,' etc. Only studies were included reviewing the Porphyromonas Gingivalis and its role in periodontitis. It has been observed from several oral pathogens that P. gingivalis has received immense attention due to a strong association between Porphyromonas Gingivalis and periodontal disease. Porphyromonas Gingivalis also disrupts the delicate balance between various members of the oral microbial communities and promotes oral dysbiosis. The dysbiotic state of the oral microbiome is distinct in functional capabilities and shows a higher expression of genes involved in lipopolysaccharide synthesis, energy regulation, and bacterial motility. Certain virulence factors such as gingipains, LPS, and fimbriae also increase the invasion and pathogenicity of Porphyromonas Gingivalis. Its presence in the periodontal tissues increases the secretion of numerous pro-inflammatory mediators such as TNF-α, IL-8, and IL-1β, leading to the destruction of soft gingival tissues and ligaments. Early detection of periodontitis and immediate treatment can prevent soft tissue destruction and dentition loss. In conclusion, details about the oral microbiome, oral dysbiosis, and inflammation may offer new therapeutic options in the future, including a personalized approach and the use of combination therapy.

Electrospun Nanofibers for Periodontal Treatment: A Recent Progress

Periodontitis is a major threat to oral health, prompting scientists to continuously study new treatment techniques. The nanofibrous membrane prepared via electrospinning has a large specific surface area and high porosity. On the one hand, electrospun nanofibers can improve the absorption capacity of proteins and promote the expression of specific genes. On the other hand, they can improve cell adhesion properties and prevent fibroblasts from passing through the barrier membrane. Therefore, electrospinning has unique advantages in periodontal treatment. At present, many oral nanofibrous membranes with antibacterial, anti-inflammatory, and tissue regeneration properties have been prepared for periodontal treatment. First, this paper introduces the electrospinning process. Then, the commonly used polymers of electrospun nanofibrous membranes for treating periodontitis are summarized. Finally, different types of nanofibrous membranes prepared via electrospinning for periodontal treatment are presented, and the future evolution of electrospinning to treat periodontitis is described.

Pharmacological Therapies for the Management of Inflammatory Bone Resorption in Periodontal Disease: A Review of Preclinical Studies

Periodontitis, a highly prevalent multicausal chronic inflammatory and destructive disease, develops as a result of complex host-parasite interactions. Dysbiotic bacterial biofilm in contact with the gingival tissues initiates a cascade of inflammatory events, mediated and modulated by the host's immune response, which is characterized by increased expression of several inflammatory mediators such as cytokines and chemokines in the connective tissue. If periodontal disease (PD) is left untreated, it results in the destruction of the supporting tissues around the teeth, including periodontal ligament, cementum, and alveolar bone, which lead to a wide range of disabilities and poor quality of life, thus imposing significant burdens. This process depends on the differentiation and activity of osteoclasts, the cells responsible for reabsorbing the bone tissue. Therefore, the inhibition of differentiation or activity of these cells is a promising strategy for controlling bone resorption. Several pharmacological drugs that target osteoclasts and inflammatory cells with immunomodulatory and anti-inflammatory effects, such as bisphosphonates, anti-RANK-L antibody, strontium ranelate, cathepsin inhibitors, curcumin, flavonoids, specialized proresolving mediators, and probiotics, were already described to manage inflammatory bone resorption during experimental PD progression in preclinical studies. Meantime, a growing number of studies have described the beneficial effects of herbal products in inhibiting bone resorption in experimental PD. Therefore, this review summarizes the role of several pharmacological drugs used for PD prevention and treatment and highlights the targeted action of all those drugs with antiresorptive properties. In addition, our review provides a timely and critical appraisal for the scientific rationale use of the antiresorptive and immunomodulatory medications in preclinical studies, which will help to understand the basis for its clinical application.

The ever-changing landscape in modern dentistry therapeutics - Enhancing the emptying quiver of the periodontist

Introduction/Objectives

Periodontitis comprises of a wide range of inflammatory conditions of the gums leading to soft tissue damage and attachment loss. The initiation of periodontitis constitutes a rather complex disease pathogenesis which is based on pathogenic shifts of the oral microbiota combined with the host-microbiome interactions. The severity of the periodontitis is multifactorial depending on genetic, environmental, as well as host immunity factors.

Data and sources

To make an inclusive analysis on the periodontitis therapeutics, reading of the recent relevant literature was carried out using the MEDLINE/PubMed database, Google Scholar and the NIH public online database for clinical trials (http://www.clinicaltrials.gov).

Conclusions

Tackling the inflammation associated periodontal defects can be succeeded with conventional therapy or resective and regenerative treatment. To date, the mechanical removal of the supragingival and subgingival biofilm is considered the “gold standard” of periodontal therapy in combination with the use of antibacterial compounds. The antimicrobial resistance phenomenon tends to turn all the currently applied antibacterials into “endangered species”. Ongoing efforts through the conduct of clinical trials should be focused on understanding the advantages of modern approaches in comparison to traditional therapies.

Impact on Porphyromonas gingivalis of antimicrobial photodynamic therapy with blue light and Rose Bengal in plaque-disclosing solution

OBJECTIVES

Antimicrobial photodynamic therapy (aPDT) in periodontal pockets using lasers is difficult to perform in some cases because of the high cost of irradiation equipment and the narrow irradiation field. The purpose of the present study was to examine the effects of aPDT in combination with a plaque-disclosing solution and blue light-emitting diode (LED), which are used for composite resin polymerization.

METHODS

The reactive oxygen species generated by irradiating 0.001% RB or MB with blue light were analyzed using electron spin resonance spectroscopy. Blue-light exposure was performed at 6.92, 20.76 and 124.6 J. The microorganism to be sterilized was Porphyromonas gingivalis. After aPDT, colony-forming units (CFUs) were measured to estimate cell survival. Carbonylated protein (PC) levels were used to evaluate oxidative stress. All statistical analyses were performed with Tukey's multiple comparisons test or the unpaired t-test.

RESULTS

Singlet oxygen (¹O₂) generation was confirmed by RB+blue LED. ¹O₂ production was significantly greater with the blue LED irradiation of RB than that of MB (p < 0.0001). CFUs were significantly lower in the blue LED-irradiated group than in the non-LED-irradiated group (p < 0.01). The bactericidal effect increased in a time-dependent manner. aPDT increased PC levels. No morphological changes were observed in P. gingivalis.

CONCLUSIONS

The present results suggest that aPDT exerts bactericidal effects against P. gingivalis by increasing oxidative stress through the generation of ¹O₂ in cells. Periodontal disease may be treated by aPDT using the equipment available in dental offices.

Influence of Titania Nanotubes Diameter on Its Antibacterial Efficacy against Periodontal Pathogens: An In vitro Analysis

Background

Peri implant infection in dental implantology is a frequently encountered clinical problem. Titania nanotubes (TNTs) are recent improvement in surface characterization, showing promising results.

Aim

The nanosurface parameter tweaking has been implicated with profound change in the microbiological and biological response. Hence, it was proposed that alteration in the nanotube diameter could have positive influence in its antibacterial activity against salient periodontal pathogens.

Materials and Methods

Commercially, pure titanium discs of 8-mm diameter and 1.5-mm thickness were prepared. Polished titanium discs were used as control (Group A). Vertically oriented, structured TNTs were fabricated by anodization technique and grouped as B and C, having nanotube diameter, 40 and 80 nm subsequently. The surface characterizations of the samples were done by scanning electron microscope analysis. The antibacterial activity was evaluated with the bacterial colony counting method, at 24 h, 72 h, and 1-week intervals.

Statistical Analysis

The one-way analysis of variance and Tukey's honest significance post hoc test were employed to assess the statistical significance.

Results

The 80 nm nanotubes showed better antibacterial activity comparatively, at all three-time intervals investigated.

Conclusion

The optimal TNT diameter of 80 nm was the most effective from an antimicrobial stand point of view.

Meloxicam-loaded solvent exchange-induced in situ forming beta-cyclodextrin gel and microparticle for periodontal pocket delivery

The in situ forming system has attracted attention for periodontitis treatment owing to its sustainable drug release localisation at a periodontal pocket. Given its low aqueous solubility, beta-cyclodextrin (β-CD) may serve as a matrix former of solvent exchange-induced in situ forming gel (ISG) and microparticle (ISM). Meloxicam (Mex)-loaded-β-CD ISG and ISM were prepared using β-CD in dimethyl sulphoxide (ISG) as the internal phase and camellia oil comprising 5% glyceryl monostearate as the external phase (ISM). Mex-loaded β-CD systems comprising 40% β-CD were easily injected via a 24-gauge needle. During solvent exchange with phosphate buffer saline (pH 6.8), the highly concentrated β-CD ISG promoted the phase inversion of β-CD aggregates into matrix-like. Upon exposure to aqueous phase, the ISM system comprising 40% β-CD transformed into microparticles and extended the drug release to 7 days with minimised initial burst release following Fickian diffusion. Moreover, the potential degradability was evident from the high weight loss. High maximum deformation force with high viscous character initiated the slow diffusion rate of the solvent from the ISM system. Therefore, 40% β-CD ISM is a potential local Mex-controlled release system of anti-inflammatory drug for periodontitis treatment.

Research Advances in the Use of Bioactive Compounds from Vitis vinifera By-Products in Oral Care

Oral health is considered an important factor of general health and it contributes to the quality of life. Despite the raising awareness of preventive measures, the prevalence of oral health conditions continues to increase. In this context, a growing interest in investigating natural resources like Vitis vinifera (V. vinifera) phenolic compounds (PhCs) as oral health promoters has emerged. This paper aims to review the evidence about the bioactivities of V. vinifera by-products in oral health. Up to date, a high number of studies have thoroughly reported the antimicrobial and antiplaque activity of V. vinifera extracts against S. mutans or in multi-species biofilms. Moreover, the bioactive compounds from V. vinifera by-products have been shown to modulate the periodontal inflammatory response and the underlying oxidative stress imbalance induced by the pathogenic bacteria. Considering these beneficial effects, the utility of V. vinifera by-products in the maintaining of oral health and the necessary steps towards the development of oral care products were emphasized. In conclusion, the high potential of V. vinifera by-products could be valorized in the development of oral hygiene products with multi-target actions in the prevention and progression of several oral conditions.

Functionalized nanoparticles containing MKP-1 agonists reduce periodontal bone loss

BACKGROUND

Progress over of the past several years has elucidated a role for mitogen-activated protein kinase phosphatase to regulate periodontal inflammation yielding new possibilities for treatment of periodontal diseases. These studies aimed to determine if nanoparticles (NPs) loaded with a pharmacological agent that induces mitogen-activated protein kinase phosphatase have potential clinical utility for management of periodontal inflammation and alveolar bone.

METHODS

Polyethylene glycol (PEG)-polylactide (PLA) (PEG-PLA) NPs were loaded with auranofin (ARN), an antirheumatic drug, to induce mitogen-activated protein kinase phosphatase (MKP)-1 expression in vitro and in vivo. Release kinetics of ARN from NPs was performed by high performance liquid chromatography (HPLC). Fluorescent-labeled NPs were used to show uptake into macrophages by flow cytometry. Real-time quantitative polymerase chain reaction (qPCR) was used to determine dual specificity protein phosphatase (Dusp)-1 mRNA induction by Auranofin-loaded nanoparticles (ARN-NPs) and viability of ARN-NPs was determined by colorimetric in vitro assays. Functional in vitro assays were used to measure functional MKP-1 induction and preclinical models using Aggregatibacter actinomycetemcomitans lipopolysaccharide-induced alveolar bone loss and microcomputed tomography was used to determine in vivo efficacy of functionalized ARN-NPs.

RESULTS

Data indicated that ARN-NPs had reduced cytotoxicity compared with free ARN and Dusp1 mRNA and MKP-1 activity was significantly increased by ARN-NPs in vitro. Flow cytometry indicated rapid uptake into macrophages. Finally, significant bone loss reduction was observed with ARN-NPs compared with control NPs in vivo using an lipopolysaccharide-induced rat model of periodontitis.

CONCLUSION

Results from these studies suggest that developing NPs functionalized with ARN have anti-inflammatory activities and may be a novel adjuvant therapeutic strategy to significantly improve periodontitis therapy and outcomes.

Sustained co-delivery of ibuprofen and basic fibroblast growth factor by thermosensitive nanoparticle hydrogel as early local treatment of peri-implantitis

Objective

The aims of this study were to 1) encapsulate ibuprofen (IBU) and basic fibroblast growth factor (bFGF) in a thermosensitive micellar hydrogel, 2) test the biological properties of this in situ drug delivery system, and 3) study the effect of hydrogel in promoting soft tissue healing after implant surgery and its anti-inflammatory function as an early local treatment of peri-implantitis.

Materials and methods

A thermosensitive micellar hydrogel was prepared from amphiphilic copolymer poly(ε-caprolactone-co-1,4,8-trioxa [4.6]spiro-9-undecanone)-poly(ethylene glycol)-poly(ε-caprolactone-co-1,4,8-trioxa [4.6]spiro-9-undecanone) (PECT) nanoparticles and tested in vitro using a scanning electron microscope, rheometer, UV spectrophotometer, HPLC, and transmission electron microscope.

Results

The bFGF + IBU/PECT hydrogel formed a stable, water-dispersible nanoparticle core shell that was injectable at room temperature, hydrogel in situ at body temperature, and provided sustained release of both hydrophilic and hydrophobic drugs. The hydrogel promoted the proliferation and adhesion of human gingival fibroblasts, upregulated the expression of adhesion factors such as vinculin proteins, and showed anti-inflammatory properties.

Conclusion

In situ preparation of IBU-and bFGF-loaded PECT hydrogel represents a promising drug delivery system with the potential to provide early local treatment for peri-implantitis.

Comparison of clinical effectiveness of single and multiple applications of 1% chlorhexidine varnish (Cervitec Plus) along with scaling and root planing in patients with chronic periodontitis

Background:

Local drug delivery is most commonly used as an adjunct to scaling and root planing (SRP) for the treatment of periodontal disease. Varied success rates have been documented for various vehicles used for intrasite delivery of active therapeutic agents. Recently, varnishes acting as a reservoir of chlorhexidine have shown potential for the management of chronic periodontitis patients. The aim of the present investigation was a comparative evaluation of the clinical effectiveness of single and multiple applications of 1% chlorhexidine and thymol varnish (Cervitec Plus) along with SRP in patients with chronic periodontitis.

Materials and Methods:

The present study included 30 patients with chronic periodontitis divided into three groups based on the number of subgingival applications of chlorhexidine varnish single application (Group A), two applications at a week's interval (Group B), and three applications with 7-day interval in between two applications (Group C). Clinical parameters, namely plaque index (PI), sulcus bleeding index, probing pocket depth (PPD), and relative attachment level (RAL) were recorded at baseline, 1 month and 3 months in all three groups to compare the clinical efficacy.

Results:

A statistically significant reduction was observed in PI, sulcus bleeding index, PPD, and RAL at 1 and 3 months in all the three groups. Greater (though statistically nonsignificant) improvements were observed in Groups B and C.

Conclusion:

Within limitations of the study, it can be concluded that multiple applications of 1% chlorhexidine and thymol varnish (Cervitec Plus) have an added benefit over the single application in the treatment of chronic periodontitis.

Polyphenols in the prevention and treatment of periodontal disease: A systematic review of in vivo, ex vivo and in vitro studies

Plant-derived polyphenols with antimicrobial and immunomodulatory characteristics appear to provide a variety of oral health benefits. Thus, the aim of the present study was to review the scientific literature to identify these effects of polyphenols on periodontal pathogens and inflammation. A MEDLINE search from 1st January 2013 to 18th January 2018 was performed to identify studies reporting polyphenol-containing plant extracts. Reports regarding pure compounds and essential oils, as well as effects on bacteria that are not defined as periodontal pathogens, were excluded. Thirty-eight studies matched the selection criteria. Studies on immunomodulatory effects included in vitro, ex vivo, and in vivo studies (n = 23), whereas studies reporting antibacterial effects against periodontal pathogens included only in vitro studies (n = 18). Three studies were included in both groups. The antibacterial effects were characterised by inhibition of bacterial growth, adhesion to oral cells, and enzymatic activity. Decreased secretion of pro-inflammatory and increased secretion of anti-inflammatory cytokines were demonstrated. Higher attachment levels, lower inflammation, and bone loss were reported by in vivo studies. Due to the high heterogeneity, it is difficult to draw clear conclusions for applicability; nevertheless, polyphenols have great potential as antimicrobial and immunomodulatory substances in the treatment and prevention of periodontal disease.

Inhibition of the histone demethylase KDM4B leads to activation of KDM1A, attenuates bacterial-induced pro-inflammatory cytokine release, and reduces osteoclastogenesis

Periodontal disease (PD) afflicts 46% of Americans with no effective adjunctive therapies available. While most pharmacotherapy for PD targets bacteria, the host immune response is responsible for driving tissue damage and bone loss in severe disease. Herein, we establish that the histone demethylase KDM4B is a potential drug target for the treatment of PD. Immunohistochemical staining of diseased periodontal epithelium revealed an increased abundance of KDM4B that correlates with inflammation. In murine calvarial sections exposed to Aggregatibacter actinomycetemcomitans lipopolysaccharide (Aa-LPS), immunohistochemical staining revealed a significant increase in KDM4B protein expression. The 8-hydroxyquinoline ML324 is known to inhibit the related demethylase KDM4E in vitro, but has not been evaluated against any other targets. Our studies indicate that ML324 also inhibits KDM4B (IC50: 4.9 μM), and decreases the pro-inflammatory cytokine response to an Aa-LPS challenge in vitro. Our results suggest that KDM4B inhibition-induced immunosuppression works indirectly, requiring new protein synthesis. In addition, fluorescence-stained macrophages exhibited a significant decrease in global monomethyl histone 3 lysine 4 (H3K4me) levels following an Aa-LPS challenge that was prevented by KDM4B inhibition, suggesting this effect is produced through KDM1A-mediated demethylation of H3K4. Finally, ML324 inhibition of KDM4B in osteoclast progenitors produced a significant reduction in Aa-LPS-induced osteoclastogenesis. These data link histone methylation with host immune response to bacterial pathogens in PD, and suggest a previously unreported, alternative mechanism for epigenetic control of the host inflammatory environment. As such, KDM4B represents a new therapeutic target for treating hyper-inflammatory diseases that result in bone destruction.

Local Application of Pyrophosphorylated Simvastatin Prevents Experimental Periodontitis

PURPOSE

Simvastatin (SIM), a HMG-CoA reductase inhibitor widely prescribed for hypercholesterolemia, has been reported to ameliorate inflammation and promote osteogenesis. Its clinical applications on these potential secondary indications, however, have been hampered by its lack of osteotropicity and poor water solubility. To address this challenge, we propose to design and evaluate the therapeutic efficacy of a novel simvastatin prodrug with better water solubility and bone affinity.

METHOD

The prodrug (SIM-PPi) was synthesized by directly conjugating a SIM trimer to a pyrophosphate (PPi). It was characterized and evaluated in vitro for its water solubility, osteotropicity, toxicity, anti-inflammatory and osteoinductive properties. It was then tested for anti-inflammatory and osteoinductive properties in vivo by three weekly injections into gingiva of a ligature-induced experimental periodontitis rat model.

RESULTS

In vitro studies showed that SIM-PPi has greatly improved water-solubility of SIM and shows strong binding to hydroxyapatite (HA). In macrophage culture, SIM-PPi inhibited LPS-induced pro-inflammatory cytokines (IL-1β, IL-6). In osteoblast culture, it was found to significantly increase alkaline phosphatase (ALP) activity with accelerated mineral deposition, confirming the osteogenic potential of SIM-PPi. When tested in vivo on an experimental periodontal bone-loss model, SIM-PPi exhibited a superior prophylactic effect compared to dose equivalent SIM in reducing inflammatory cells and in preserving alveolar bone structure, as shown in the histological and micro-CT data.

CONCLUSION

SIM-PPi may have the potential to be further developed for better clinical management of bone loss associated with periodontitis.

Development of hydrogels, oleogels, and bigels as local drug delivery systems for periodontitis

Periodontal disease is a chronic inflammation of gum and tissues that surround and support the teeth. Nonsteroidal anti-inflammatory drugs (NSAIDs) can be used in the treatment of periodontitis to ease swelling and inflammation. One approach of treating periodontitis is loading the NSAIDs in local drug delivery systems. Therefore, the objective of this study was to investigate the local delivery of the NSAIDs model drug ibuprofen to treat periodontitis using different types of gel formulations (hydrogel, oleogel, and bigel). Gel formulations were characterized in terms of their rheological properties (flow behavior, viscoelastic, and bioadhesive properties) using a controlled-stress rheometer. The in vitro drug release of ibuprofen from gel formulations was investigated using Franz diffusion cells. Gels exhibited more solid-like (elastic) behavior. The viscosity and viscoelastic properties were in the order of oleogel > bigel > hydrogel, respectively. In bioadhesion study, mucin dispersion/plain ibuprofen-hydrogel mixture showed a frequency-dependent interaction of ΔG' = -31 and ΔG' = + 53 Pa at 1 and 10 rad/s, respectively. A strong positive interaction (ΔG' = + 6000 and +130,667 Pa at 1 and 10 rad/s, respectively) was found in mucin dispersion/plain ibuprofen-oleogel mixture. The extent of the negative interaction increased in mucin dispersion/plain ibuprofen-bigel mixture (ΔG' = -59,000 and -79,375 Pa at 1 and 10 rad/s, respectively). After 6 h, ibuprofen release from hydrogel, oleogel, and bigel was 59.5 ± 2.2, 80.6 ± 3.9, and 94.6 ± 3.2%, respectively. Results showed that the rheological and bioadhesive properties and in vitro drug release were influenced by the type of gel formulations.

Alternative practices of achieving anaesthesia for dental procedures: a review

Managing pain and anxiety in patients has always been an essential part of dentistry. To prevent pain, dentists administer local anaesthesia (LA) via a needle injection. Unfortunately, anxiety and fear that arise prior to and/or during injection remains a barrier for many children and adults from receiving dental treatment. There is a constant search for techniques to alleviate the invasive and painful nature of the needle injection. In recent years, researchers have developed alternative methods which enable dental anaesthesia to be less invasive and more patient-friendly. The aim of this review is to highlight the procedures and devices available which may replace the conventional needle-administered local anaesthesia. The most known alternative methods in providing anaesthesia in dentistry are: topical anaesthesia, electronic dental anaesthesia, jet-injectors, iontophoresis, and computerized control local anaesthesia delivery systems. Even though these procedures are well accepted by patients to date, it is the authors' opinion that the effectiveness practicality of such techniques in general dentistry is not without limitations.

Guided bone regeneration with asymmetric collagen-chitosan membranes containing aspirin-loaded chitosan nanoparticles

Introduction

Membranes allowing the sustained release of drugs that can achieve cell adhesion are very promising for guided bone regeneration. Previous studies have suggested that aspirin has the potential to promote bone regeneration. The purpose of this study was to prepare a local drug delivery system with aspirin-loaded chitosan nanoparticles (ACS) contained in an asymmetric collagen-chitosan membrane (CCM).

Methods

In this study, the ACS were fabricated using different concentrations of aspirin (5 mg, 25 mg, 50 mg, and 75 mg). The drug release behavior of ACS was studied. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to examine the micromorphology of ACS and aspirin-loaded chitosan nanoparticles contained in chitosan-collagen membranes (ACS-CCM). In vitro bone mesenchymal stem cells (BMSCs) were cultured and critical-sized cranial defects on Sprague-Dawley rats were made to evaluate the effect of the ACS-CCM on bone regeneration.

Results

Drug release behavior results of ACS showed that the nanoparticles fabricated in this study could successfully sustain the release of the drug. TEM showed the morphology of the nanoparticles. SEM images indicated that the asymmetric membrane comprised a loose collagen layer and a dense chitosan layer. In vitro studies showed that ACS-CCM could promote the proliferation of BMSCs, and that the degree of differentiated BMSCs seeded on CCMs containing 50 mg of ACS was higher than that of other membranes. Micro-computed tomography showed that 50 mg of ACS-CCM resulted in enhanced bone regeneration compared with the control group.

Conclusion

This study shows that the ACS-CCM would allow the sustained release of aspirin and have further osteogenic potential. This membrane is a promising therapeutic approach to guiding bone regeneration.

Clinical Evaluation of Effects of Local Application of Aloe vera Gel as an Adjunct to Scaling and Root Planning in Patients with Chronic Periodontitis

STATEMENT OF THE PROBLEM

Aloe vera gel contains various components with antibiotic and anti-inflammatory characteristics, which may have potential advantages to treat periodontal diseases.

PURPOSE

The aim of this study was to evaluate the effects of local application of aloe vera gel as an adjunct to scaling and root planning in the treatment of patients with chronic periodontitis.

MATERIALS AND METHOD

This single-blind clinical trial, performed in a split mouth design, was conducted on 20 patients with moderate to severe chronic periodontitis. Following a baseline examination at first day which included the assessments of plaque index (PI), gingival index (GI), and probing depth (PD); patients randomly received either SRP in one quadrant (control group), or SRP combined with aloe vera gel in another quadrant (experimental group). All cases were examined again, assessing PI, GI, and PD at 30^th and 60^th day.

RESULTS

There was no significant difference in PI in the three stages between control and experimental groups. In all patients, there was a significant improvement in the three stages in GI and PD for both quadrants treated only with SRP or combination of SRP and aloe vera. However, experimental group presented significantly lower GI (p= 0.0001) and PD (p= 0.009) than the control group at the end of study period.

CONCLUSION

This study revealed that local application of aloe vera gel could be considered as an adjunctive treatment with scaling and root planning for chronic periodontitis.

Lower dosage of aspirin promotes cell growth and osteogenic differentiation in murine bone marrow stromal cells

Background/purpose

The effect of aspirin on bone regeneration remains controversial. This study aimed to determine the effect of various concentrations of aspirin on cell viability, osteogenic differentiation, cell cycle, and apoptosis on ST2 cells to find an effective range of aspirin for bone regeneration induction.

Materials and methods

Cell viability was measured with MTT assay after being stimulated with aspirin for 1 day, 2 days, 3 days, 5 days, and 7 days. Alkaline phosphatase (ALP) activity was measured after cells were treated for 1 day, 3 days, and 7 days. Expression of runt-related transcription factor 2 (Runx-2) was evaluated using Western-blot analysis at 3 days and 7 days. Flow cytometry was used for cell cycle and apoptosis measurement after cells were treated for 48 hours.

Results

Lower concentrations of aspirin (1μΜ and 10μM) promoted cell growth and increased ALP levels and Runx-2 expression, while higher concentrations (100μΜ and 1000μΜ) inhibited cell growth (P < 0.05), and lost their effect on ALP activity after 3 days, while even showing an inhibitory effect on the expression of Runx-2. Aspirin at a concentration of 100μM promoted cell mitosis from the S phase to the G2/M phase, and 1000μM arrested the cell cycle in the resting phase G0/G1 (P < 0.05). Parallel apoptosis/necrosis studies showed the percentage of cells in apoptosis decreased dramatically at any dose of aspirin.

Conclusion

A lower dosage of aspirin could promote ST2 cell growth, osteogenic differentiation, and inhibit their apoptosis which indicates that aspirin can be used as an alternative for bone regeneration.

In vitro behavior of poly-lactic-co-glycolic acid microspheres containing minocycline, metronidazole, and ciprofloxacin

AIM

In the present study, we aimed to fabricate poly-lactic-co-glycolic acid (PLGA) microspheres containing a mixture of three antibiotics-minocycline, metronidazole, and ciprofloxacin (MMC)-to assess their efficacy and properties.

METHODS

MMC were loaded onto PLGA biopolymer microspheres at a 1:1:1 ratio using the double emulsion technique. The morphology of microspheres was observed by a (SEM). The controlled release of antibiotics was evaluated over an 18-day period. The antibacterial efficacy of released antibiotics against Aggregatibacter actinomycetemcomitans was evaluated by measuring the diameter of the growth-inhibition zone. The cytotoxicity of MMC-containing microspheres was also evaluated and compared using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. One-way anova was used for the data analysis.

RESULTS

SEM micrographs confirmed the spherical shape and smooth surface of microspheres. The adequate release of antibiotics was observed from the microspheres within the desired time period of 16-18 days. The MMC-containing microspheres showed antibacterial activity for 11 days. Moreover, MMC-containing microspheres showed superior cell biocompatibility compared to the free mixture of the three antibiotics (P < 0.05).

CONCLUSION

Microspheres containing triple antibiotics showed good release, antibacterial activity for 11 days, and similar cell biocompatibility compared to the empty microspheres.

Detection and measurement of oral malodor in chronic periodontitis patients and its correlation with levels of select oral anaerobes in subgingival plaque

Introduction:

Oral malodor is generally ascribable to oral microbial putrefaction generating malodorous volatile sulfur compounds. The aim of the present study is to correlate organoleptic recordings with a small handheld portable volatile sulfide monitor and periodontal clinical parameters and correlate the levels of halitosis causing bacteria in plaque between baseline, 1-week, and 1-month.

Materials and Methods:

A total of 20 systemically healthy subjects with self-reported halitosis were subjected to organoleptic examination and FitScan^®. Subgingival plaque samples for anaerobic culturing were harvested followed by an assessment of plaque index (PI), gingival bleeding index (GBI), and pocket probing depth. Data derived were subjected to statistical analysis using Wilcoxon signed rank test and Spearman's rank test (P < 0.05).

Results:

No correlation was seen between organoleptic measurements and portable volatile sulfide monitor at any time interval. There was a statistically significant (P < 0.05) correlation between the scores of PI, gingival index, GBI, and myeloproliferative disease with organoleptic readings at all-time intervals. Anaerobic culture has shown to identify Fusobacterium species, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia. However, no correlation could be established in between total microbial load with organoleptic and FitScan^® reading at any time interval (P < 0.05).

Conclusion:

Significant correlation could be established between organoleptic readings and periodontal parameters.

Complement therapeutics in inflammatory diseases: promising drug candidates for C3-targeted intervention

There is increasing appreciation that complement dysregulation lies at the heart of numerous immune-mediated and inflammatory disorders. Complement inhibitors are therefore being evaluated as new therapeutic options in various clinical translation programs and the first clinically approved complement-targeted drugs have profoundly impacted the management of certain complement-mediated diseases. Among the many members of the intricate protein network of complement, the central component C3 represents a 'hot-spot' for complement-targeted therapeutic intervention. C3 modulates both innate and adaptive immune responses and is linked to diverse immunomodulatory systems and biological processes that affect human pathophysiology. Compelling evidence from preclinical disease models has shown that C3 interception may offer multiple benefits over existing therapies or even reveal novel therapeutic avenues in disorders that are not commonly regarded as complement-driven, such as periodontal disease. Using the clinically developed compstatin family of C3 inhibitors and periodontitis as illustrative examples, this review highlights emerging therapeutic concepts and developments in the design of C3-targeted drug candidates as novel immunotherapeutics for oral and systemic inflammatory diseases.

Inhibitors of bacterial protease enzymes for periodontal therapy

Locally applied therapeutic agents have become established in the treatment of periodontal disease. Inhibition of human metalloproteases by metal-chelating antibiotics contributes to the utility of local therapy. Adding inhibitors of bacterial proteases might extend and improve local therapy. The periodontal pathogen Porphyromonas gingivalis (Pg) produces two extracellular cysteine proteases (gingipains Rgp and Kgp) that are virulence factors and contribute to destruction of oral tissues. Our aims were to compare efficacy of protease inhibitors against gingipains and evaluate bactericidal activity of the inhibitors. Protease activity was measured in fluorescent assays with specific Rgp and Kgp substrates. Bacterial viability was measured with BacLight™ (Invitrogen, Inc., Carlsbad, CA) reagents. Pairs of inhibitors of Rgp and Kgp, respectively, were leupeptin and cathepsin B inhibitor II, KYT-1 and KYT-36, and PPACK and Z-FK-ck. The cysteine-protease inhibitor E64 was also tested. Rgp activity was higher than Kgp activity, and activity was higher in Pg 33277 and 49417 cell suspensions than in media. Concentrations required for 50% inhibition of Rgp in cell suspensions were 2 × 10-9, 2 × 10-9, 2 × 10-8, and 5 × 10-5 M for KYT-1, PPACK, leupeptin, and E64, respectively. Concentrations required for 50% Kgp inhibition were 5 × 10-10, 1 × 10-9, and 5 × 10-8 M for Z-FK-ck, KYT-36, and cathepsin B inhibitor II. E64 did not inhibit Kgp. Inhibition of Rgp could be accounted for by competition for binding between the arginine residue of the substrate and the guanidinobutane portion of E64. PPACK was the least selective, with a 10-fold difference in concentrations that inhibited Rgp and Kgp. KYT-1 and Z-FK-ck inhibited both Rgp and Kgp, but inhibitory concentrations differed by 10,000-fold. At up to 1 × 10-4 M, only Z-FK-ck was bactericidal. KYT-1 and KYT-36 were remarkably effective even when used in cell suspensions in which bacterial proteins could bind inhibitors or compete for binding to gingipains. These inhibitors might prove useful as an addition to locally applied therapeutic agents.

Effects of curcumin on crevicular levels of IL-1β and CCL28 in experimental gingivitis

BACKGROUND

Curcumin has anti-inflammatory properties. The aim of this study was to compare interleukin-1β (IL-1β) and chemokine (C-C motif) ligand 28 (CCL28) levels following a topical application of curcumin (CRM), chlorhexidine (CHX) and chlorhexidine-metronidazole (CHX-MTZ) in an experimental gingivitis human model.

METHODS

Sixty systemically healthy selected subjects were randomly assigned to one of three topical antigingivitis gels. Each gel was applied twice daily for 10 minutes as the sole method of oral hygiene for 29 days on the test quadrant only. Modified gingival index (MGI), plaque index (PI), bleeding on probing (BOP) and probing depth (PD) were assessed at baseline, 29 days and 60 days. Estimation of IL-1β and CCL28 levels in gingival crevicular fluid was done at baseline and at 29 days.

RESULTS

The increase of IL-1β in the CRM (14.52 ± 16.6 pg/ml) and CHX-MTZ (31.63 ± 15.96) groups was significantly less than that of the CHX group (70.55 ± 38.81). Similar results were also observed for CCL28 (CRM: 8.12 ± 8.78 pg/ml; CHX-MTZ: 12.81 ± 18.68; CHX: 41.15 ± 22.82). All groups had a significant increase in MGI, PI and BOP at 29 days.

CONCLUSIONS

The anti-inflammatory potential of topical curcumin was similar to CHX-MTZ but superior to CHX in affecting IL-1β and CCL28 levels.

Decontamination methods using a dental water jet and dental floss for microthreaded implant fixtures in regenerative periimplantitis treatment

OBJECTIVE

This study evaluated decontamination methods using a dental water jet and dental floss on microthreaded implants for regenerative periimplantitis therapy.

MATERIALS AND METHODS

In 6 beagle dogs, experimental periimplantitis was induced, and decontamination procedures, including manual saline irrigation (control group), saline irrigation using a dental water jet (group 1) and saline irrigation using a dental water jet with dental flossing (group 2), were performed. After in situ decontamination procedures, some of the implant fixtures (n = 4 per group) were retrieved for analysis by SEM, whereas other fixtures (n = 4 per group) underwent regenerative therapy. After 3 months of healing, the animals were killed.

RESULTS

The SEM examination indicated that decontamination of the implant surfaces was the most effective in group 2, with no changes in implant surface morphology. The histological examination also revealed that group 2 achieved significantly greater amounts of newly formed bone (6.75 ± 2.19 mm; P = 0.018), reosseointegration (1.88 ± 1.79 mm; P = 0.038), and vertical bone fill (26.69 ± 18.42%; P = 0.039).

CONCLUSION

Decontamination using a dental water jet and dental floss on microthreaded implants showed positive mechanical debridement effects and positive bone regeneration effects.

Complement Involvement in Periodontitis: Molecular Mechanisms and Rational Therapeutic Approaches

The complement system is a network of interacting fluid-phase and cell surface-associated molecules that trigger, amplify, and regulate immune and inflammatory signaling pathways. Dysregulation of this finely balanced network can destabilize host-microbe homeostasis and cause inflammatory tissue damage. Evidence from clinical and animal model-based studies suggests that complement is implicated in the pathogenesis of periodontitis, a polymicrobial community-induced chronic inflammatory disease that destroys the tooth-supporting tissues. This review discusses molecular mechanisms of complement involvement in the dysbiotic transformation of the periodontal microbiome and the resulting destructive inflammation, culminating in loss of periodontal bone support. These mechanistic studies have additionally identified potential therapeutic targets. In this regard, interventional studies in preclinical models have provided proof-of-concept for using complement inhibitors for the treatment of human periodontitis.

Non-surgical periodontal therapy: An update on current evidence

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

Diseases of the mouth

Oral pathologic abnormality is common and can be potentially serious. There are many diseases of the mouth that medical personnel must be able to diagnose and initiate management. The most prevalent lesions can be categorized as infectious, inflammatory, and common benign and malignant lesions. This article discusses prevalence, cause, diagnosis, and management of lesions such as stomatitis, candidiasis, caries, oral cancers, and bony tori.

Therapeutic effects of local drug delivery systems - PerioChip® in the treatment of periodontal disease

The primary goal of periodontal treatment is to stop periodontal disease progression and reduce future risks in disease recurrence. In order to overcome the limitations of the conventional treatment, controlled drug delivery systems for application in periodontal pockets have been developed. Their use offers several advantages: the therapeutic agent is targeted directly to the disease site and concentrations are 10-100 folds higher than the concentrations achieved by systemic administration, with low incidence of side effects. The PerioChip® is as local controlled-release biodegradable delivery system containing chlorhexidine digluconate. Several multicenter clinical trials have shown that the application of the PerioChip® in periodontal pockets as adjunct to the conventional periodontal treatment significantly improved the clinical parameters. In this article, the results from controlled clinical studies aimed to evaluate the clinical and microbiological efficacy of the PerioChip®, are discussed.

Microbiota and nonalcoholic steatohepatitis

The recent rise in obesity-related diseases, such as nonalcoholic fatty liver disease and its strong association with microbiota, has elicited interest in the underlying mechanisms of these pathologies. Experimental models have highlighted several mechanisms connecting microbiota to the development of liver dysfunction in nonalcoholic steatohepatitis (NASH) such as increased energy harvesting from the diet, small intestine bacterial overgrowth, modulation of the intestinal barrier by glucagon-like peptide-2 secretions, activation of innate immunity through the lipopolysaccharide-CD14 axis caused by obesity-induced leptin, periodontitis, and sterile inflammation. The manipulation of microbiota through probiotics, prebiotics, antibiotics, and periodontitis treatment yields encouraging results for the treatment of obesity, diabetes, and NASH, but data in humans is scarce.

Effect of ethylcellulose and propylene glycol on the controlled-release performance of glyceryl monooleate-mertronidazole periodontal gel

Controlled-release metronidazole, mucoadhesive gel proposed as a drug-delivery system for periodontal application was developed and characterized. The system was based on a mixture of glycerylmonooleate (GMO) and ethylcellulose (EC). The mechanism of release depends: firstly, on the ability of GMO to form a viscous liquid crystalline mesophases and secondly on the solubilized EC to form a hydrophobic network when the mixture comes into contact with water resulting in sustaining the release of the drug. Ethylcellulose dissolved in GMO had a profound influence on the rate of drug release, reduced the initial drug release and prolonged the sustained release of metronidazole. Propylene glycol (PG) was added to increase the solubility of the drug and water was added with PG to control the viscosity. A controlled release formulation containing w/w, 20% metronidazole, 10% PG, 5% water and 65% GMO that contains 7% EC was found to be mucoadhesive, easily injectable at room temperature, and to follow Fickian diffusion release mechanism. When the drug loading was increased the drug release was accelerated, and the mechanism followed anomalous controlled-release mechanism. Stability studies indicated that the formulation should be stored at 4 °C in a dark place.

In vitro evaluation of the oxidation efficacy of transgingival photodynamic therapy

OBJECTIVE

To evaluate the capability of soft laser light to penetrate blood, serum, gingival connective tissue and pure collagen type I.

MATERIALS AND METHODS

A 1:1 mixture of methylene blue (MB) and diphenylisobenzofuran (DPBF) was irradiated for 60 s with a diode laser (670 nm, 0.3 W) through blood, serum, gingival connective tissue and collagen type I (2 mm transillumination thickness). The oxidation of DPBF by MB was determined spectrophotometrically by measuring the optical density (oD) at 410 nm. The absorption spectra of DPBF/MB irradiated through MB (1%) and strawberry red solution (3%) served as control.

RESULTS

The mean oD of non-irradiated DPBF/MB was 1.98 ± 0.04. Irradiation through MB showed no oxidation of DPBF (1.98 ± 0.02; p > 0.05), while interposition of strawberry red and serum resulted in almost complete oxidation of DPBF (0.13 ± 0.09, 0.06 ± 0.03; p ≤ 0.0001). Irradiation through gingiva and collagen reduced the oxidation of DPBF significantly (1.0 ± 0.04, 0.7 ± 0.04; p ≤ 0.0001), accounting for 50% to 35% of the non-irradiated DPBF/MB solution.

CONCLUSION

Red light from a diode laser can penetrate blood and gingival tissues. However, light absorption for collagen and connective tissue can hamper the oxidation process.

Anti-periodontal Pathogen and Anti-inflammatory Activities of Oxyresveratrol

Oxyresveratrol, a compound in the heartwood of Artocarpus lakoocha Roxb and other medicinal plants, has been shown to have various biological activities. However, these have not been studied in periodontal research. In this study, we investigated whether oxyresveratrol has antibacterial activity against the predominant perio-pathogenic bacteria Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Moreover, the anti-inflammatory properties of oxyresveratrol were studied in LPS-stimulated human periodontal ligament (hPDL) cells. The antibacterial activity of oxyresveratrol on P. gingivalis and A. actinomycetemcomitans was initially evaluated using a disc diffusion test. The anti-bacterial strength of oxyresveratrol was then assessed in vitro by determining the minimal inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC). Furthermore, the effects of oxyresveratrol on the LPS-induced production of inflammatory mediators were measured in hPDL cells. The levels of cytokine mRNA and protein expression were determined using reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Our results showed that oxyresveratrol exhibited antibacterial activities against P. gingivalis with MIC and MBC values of 0.07 mg/mL and 0.16 mg/mL, respectively. The MIC and MBC values against A. actinomycetemcomitans were 0.08 mg/mL and 0.16 mg/mL, respectively. When examining inflammatory stimulation, LPS treatment strongly induced the expression of pro-inflammatory cytokines in hPDL cells. However, pre-treatment with oxyresveratrol significantly inhibited the expression of IL-6 and IL-8 at both the mRNA and protein levels. The IL-1β mRNA level was suppressed by oxyresveratrol, but the level of secreted IL-1β protein was not detectable using ELISA. The results of the present study indicate that oxyresveratrol is a potential candidate for use as an anti-periodontitis agent because of its anti-bacterial activity against the main oral pathogens related to periodontal disease and its anti-inflammatory activity in LPS-stimulated hPDL cells.

Antibacterial effects of blackberry extract target periodontopathogens

BACKGROUND AND OBJECTIVE

Antimicrobial agents provide valuable adjunctive therapy for the prevention and the control of oral diseases. Limitations in their prolonged use have stimulated the search for new, naturally occurring agents with more specific activity and fewer adverse effects. Here we sought to determine the antibacterial properties of blackberry extract (BBE) in vitro against oral bacterial commensals and periodontopathogens.

MATERIAL AND METHODS

The effects of whole and fractionated BBE on the metabolism of 10 different oral bacteria were evaluated using the colorimetric water-soluble tetrazolium-1 assay. The bactericidal effects of whole BBE against Fusobacterium nucleatum were determined by quantitating the numbers of colony-forming units (CFUs). Cytotoxicity was determined in oral epithelial (OKF6) cells.

RESULTS

BBE at 350-1400 μg/mL reduced the metabolic activity of Porphyromonas gingivalis, F. nucleatum and Streptococcus mutans. The reduced metabolic activity observed for F. nucleatum corresponded to a reduction in the numbers of CFUs following exposure to BBE for as little as 1 h, indicative of its bactericidal properties. An anthocyanin-enriched fraction of BBE reduced the metabolic activity of F. nucleatum, but not of P. gingivalis or S. mutans, suggesting the contribution of species-specific agents in the whole BBE. Oral epithelial cell viability was not reduced following  exposure to whole BBE (2.24-1400 μg/mL) for ≤ 6 h.

CONCLUSION

BBE alters the metabolic activity of oral periodontopathogens while demonstrating a minimal effect on commensals. The specific antibacterial properties of BBE shown in this study, along with its previously demonstrated anti-inflammatory and antiviral properties, make this natural extract a promising target as an adjunct for prevention and/or complementary therapy of periodontal infections.

Treatment modalities and evaluation models for periodontitis

Periodontitis is the most common localized dental inflammatory disease related with several pathological conditions like inflammation of gums (gingivitis), degeneration of periodontal ligament, dental cementum and alveolar bone loss. In this perspective, the various preventive and treatment modalities, including oral hygiene, gingival irrigations, mechanical instrumentation, full mouth disinfection, host modulation and antimicrobial therapy, which are used either as adjunctive treatments or as stand-alone therapies in the non-surgical management of periodontal infections, have been discussed. Intra-pocket, sustained release systems have emerged as a novel paradigm for the future research. In this article, special consideration is given to different locally delivered anti-microbial and anti inflammatory medications which are either commercially available or are currently under consideration for Food and Drug Administration (FDA) approval. The various in vitro dissolution models and microbiological strain investigated to impersonate the infected and inflamed periodontal cavity and to predict the in vivo performance of treatment modalities have also been thrashed out. Animal models that have been employed to explore the pathology at the different stages of periodontitis and to evaluate its treatment modalities are enlightened in this proposed review.

Porphyromonas gingivalis Fimbria-Induced Expression of Inflammatory Cytokines and Cyclooxygenase-2 in Mouse Macrophages and Its Inhibition by the Bioactive Compounds Fibronectin and Melatonin

Porphyromonas gingivalis (Pg) fimbriae, in addition to lipopolysaccharide, are involved in the pathogenesis of periodontal disease. At the same time, bioactive compounds such as fibronectin (FN) and melatonin in saliva and gingival crevicular fluid have been reported to exert a preventive effect against periodontitis. Here, we review current knowledge regarding the potent inhibitory effects of FN and melatonin against Pg fimbria-induced induction of proinflammatory cytokines, cyclooxygenase-2 (COX-2) expression, and NF-kappa B activation in mouse macrophages and discuss their possible clinical application for prevention of periodontal diseases induced by oral bacteria.

Therapeutic strategies in the treatment of periodontitis

Periodontitis is a chronic inflammatory process which affects the tooth - supporting structures of the teeth. The disease is initiated by subgingival periopathogenic bacteria in susceptible periodontal sites. The host immune response towards periodontal pathogens helps to sustain periodontal disease and eventual alveolar bone loss. Although scaling and root planing is the standard treatment modality for periodontitis, it suffers from several drawbacks such as the inability to reach the base of deep pockets and doesn’t arrest migration of periodontal pathogens from other sites in the oral cavity. In order to overcome the limitations of scaling and root planning, adjunctive chemotherapeutics and host modulatory agents to the treatment are used. These therapeutic agents show substantial beneficial effects when compared to scaling and root planning alone. This review will cover an update on chemotherapeutic and past and future host immune modulatory agents used adjunctively to treat and manage periodontal diseases.