Subgingival microflora and periodontal disease

Rational design of multifunctional hydrogels targeting the microenvironment of diabetic periodontitis

Periodontitis is a chronic inflammatory disease and is the primary contributor to adult tooth loss. Diabetes exacerbates periodontitis, accelerates periodontal bone resorption. Thus, effectively managing periodontitis in individuals with diabetes is a long-standing challenge. This review introduces the etiology and pathogenesis of periodontitis, and analyzes the bidirectional relationship between diabetes and periodontitis. In this review, we comprehensively summarize the four pathological microenvironments influenced by diabetic periodontitis: high glucose microenvironment, bacterial infection microenvironment, inflammatory microenvironment, and bone loss microenvironment. The hydrogel design strategies and latest research development tailored to the four microenvironments of diabetic periodontitis are mainly focused on. Finally, the challenges and potential solutions in the treatment of diabetic periodontitis are discussed. We believe this review will be helpful for researchers seeking novel avenues in the treatment of diabetic periodontitis.

Oral microbiota of patients with phenylketonuria: A nation-based cross-sectional study

AIM

The oral microenvironment contributes to microbial composition and immune equilibrium. It is considered to be influenced by dietary habits. Phenylketonuria (PKU) patients, who follow a lifelong low-protein diet, exhibit higher prevalence of oral diseases such as periodontitis, offering a suitable model to explore the interplay between diet, oral microbiota and oral health.

MATERIALS AND METHODS

We conducted 16S rDNA sequencing on saliva and subgingival plaque from 109 PKU patients (ages 6-68 years) and 114 age-matched controls and correlated oral microbial composition and dental health.

RESULTS

PKU patients exhibited worse dental health, reduced oral microbial diversity and a difference in the abundance of specific taxa, especially Actinobacteriota species, compared to controls. PKU patients with poor periodontal health exhibited higher alpha diversity than the orally healthy ones, marked by high abundance of the genus Tannerella. Notably, the observed taxonomic differences in PKU patients with normal indices of decayed/missing/filled teeth, plaque control record, gingival bleeding index and periodontal screening and recording index generally differed from microbial signatures of periodontitis.

CONCLUSIONS

PKU patients' reduced microbial diversity may be due to their diet's metabolic challenges disrupting microbial and immune balance, thus increasing oral inflammation. Higher alpha diversity in PKU patients with oral inflammation is likely related to expanded microbial niches.

Evaluation of Adhesion and Viability of Human Gingival Fibroblasts on Strontium-Coated Titanium Surfaces: an in vitro Study

Background

Applying multifunctional coatings employing strontium (Sr) ions on titanium (Ti) surfaces is a useful and biocompatible method to improve osseointegration and prevent tissue infections through antimicrobial activity. Nonetheless, the effectiveness of Sr coating on the adhesion and viability of human gingival fibroblasts (HGFs) to Ti surfaces remains unclear.

Purpose

The study aimed to evaluate the effect of Sr coating on the adhesion and viability of HGFs to Ti surfaces.

Materials and Methods

The Ti wafers were divided into two groups based on Sr coating: uncoated Ti (control) and Sr-coated Ti. The Magnetron sputtering technique was used for Sr coating on Ti surfaces. The HGFs were seeded onto the surfaces and cultured for 48 and 96 hours before the cell adhesion and viability of the attached HGFs were assessed. The adhesion of HGFs was analyzed using the attached cell numbers at 48 h and 96 h, and the morphology at 24 h and 72 h. The cytotoxic effect on HGFs was assessed after 24 and 72 hours of incubation using cell viability assay. Student's t-test was used for statistical analysis.

Results

The number of cells attached to Sr-coated surfaces was significantly greater than those attached to uncoated Ti surfaces after 48 hours (P<0.0001) and 96 hours (P=0.0002). Sr-coated and uncoated Ti surfaces were not cytotoxic to HGFs, with the cell viability ranging from 92% to 105% of the untreated control HGFs. There were no significant differences in cell viability between Sr-coated and uncoated Ti surfaces at 24 hours (P=0.3675) and 72 hours (P=0.0982).

Conclusion

Sr-coated Ti surfaces induce adhesion of HGFs compared to uncoated Ti surfaces. Further, Sr-coated and uncoated Ti surfaces show no cytotoxic effect on the attached HGFs.

In-vitro Evaluation of Wild Bitter Melon (Momordica charantia) Extracts against Periodontopathic Bacteria (Prevotella intermedia and Porphyromonas gingivalis) using Antibacterial, Anti-Inflammatory and Molecular Docking Analysis

Wild bitter melon (Momordica charantia) extracts were prepared and their antibacterial and anti-biofilm assay were investigated against two different periodontopathic bacteria (Prevotella intermedia and Porphyromonas gingivalis) for the first time to the best of our knowledge based on the presence of different phytochemical compounds. Momordica charantia solvent extracts were prepared and phytochemical analysis was performed. Minimal inhibitory and bactericidal concentrations were determined. Antibacterial activity was evaluated using the standard well diffusion method. Anti-inflammatory studies on periodontal ligament (PDL) cell viability and lipopolysaccharide (LPS)-induced inflammation were performed. Molecular docking was investigated between the bioactive compound (Charantadiol A) of plant extract and biofilm-expressing genes in each test organism. Phytochemicals from ethanol extract showed promising results; alkaloids, flavonoids, phenols, and tannins were found present at considerable levels. The minimum inhibitory concentration was found to be 400 μg/mL for Prevotella intermedia and Porphyromonas gingivalis. Antibacterial activity expressed in terms of zone of inhibition showed 14 mm to 18 mm zones against the test organisms. The molecular docking report revealed the maximum binding energy of about -6.54 Kcal/Mol of binding energy between Charantadiol A and fimA of Porphyromonas gingivalis. Anti-biofilm study showed that the minimum biofilm eradication concentration (MBEC) of Momordica charantia expressed significantly good results against the test organisms. The PDL cell viability values expressed in percentage indicated the anti-inflammatory properties of Momordica charantia extracts at three different known concentrations. The findings concluded that Momordica charantia extracts have promising prospects as an anti-periodontopathic and anti-inflammatory agent.

Disparities and social determinants of periodontal diseases

Periodontal diseases are highly prevalent in populations worldwide and are a major global public health problem, with major negative impacts on individuals and communities. This study investigates evidence of disparities in periodontal diseases by age groups, gender, and socioeconomic factors. There is ample evidence that these diseases disproportionally affect poorer and marginalized groups and are closely associated with certain demographics and socioeconomic status. Disparities in periodontal health are associated with social inequalities, which in turn are caused by old age, gender inequality, income and education gaps, access to health care, social class, and other factors. In health care, these factors may result in some individuals receiving better and more professional care compared to others. This study also reviews the potential causes of these disparities and the means to bridge the gap in disease prevalence. Identifying and implementing effective strategies to eliminate inequities among minorities and marginalized groups in oral health status and dental care should be prioritized in populations globally.

The effect of antimicrobial photodynamic therapy on periodontal disease and glycemic control in patients with type 2 diabetes mellitus

OBJECTIVES

This study is aimed at determining the effect of concomitant antimicrobial photodynamic therapy (aPTD) on periodontal disease and glycaemic control in patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

Twenty-four patients with T2DM were enrolled in the study. Periodontal clinical parameters were assessed by measuring probing pocket depth (PPD), clinical attachment loss (CAL), gingival recession (GR), full-mouth bleeding score (FMBS), full-mouth plaque score (FMPS), and full-mouth sulcus bleeding score (FMSBS). Glycated haemoglobin A1c (HbA1c) was measured. To determine the presence of the following periodontal pathogenic bacteria, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, subgingival plaque samples were taken from two periodontal pockets per jaw with the greatest PPD using paper tips. Patients were randomly divided into the test and control group. In the test group, full-mouth disinfection was performed in combination with aPTD. In the control group, only full-mouth disinfection was performed.

RESULTS

The results showed an improvement in periodontal clinical parameters in both groups. The difference between the groups in favour of the test group was statistically significant for BOP. The HbA1c level decreased in both groups. The difference was not statistically significant. The results of the microbiological analysis suggest that the presence of periodontal pathogenic bacteria is lower with additional antimicrobial photodynamic therapy with statistically significant difference for T. forsythia.

CONCLUSIONS

Additional aPDT causes a significant reduction in BoP in the proportion of positive sites for periodontal pathogens.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT05816941.

CLINICAL RELEVANCE

aPTD is a noninvasive adjunctive therapy that can positively influence the periodontal treatment outcome.

Association between human herpes simplex virus and periodontitis: results from the continuous National Health and Nutrition Examination Survey 2009-2014

BACKGROUND

Periodontitis is a common chronic oral disease which seriously affects people's quality of life. Although human herpes simplex virus (HSV) is also found in periodontal lesions, the association between HSV infection and periodontitis is unclear.

METHODS

The National Health and Nutrition Examination Survey (NHANES) data for 2009-2010, 2011-2012 and 2013-2014 was combined, and the association between HSV infection and periodontitis in the general population and particular subgroups was investigated through weighted multi-logistic analyses.

RESULTS

There were 4,733 participants aged 30-50 years old with clinically assessed periodontitis concurrent with HSV infection. In general analysis, after adjusted for covariates, both HSV-1 (OR = 1.09, P < 0.001) and HSV-2 (OR = 1.06, P = 0.030) infection was significantly associated with periodontitis. In subgroup analyses, compared with patients without HSV infection, patients with HSV-1( +) & HSV-2( +) and HSV-1( +) & HSV-2(-) infection showed higher risk of periodontitis in all subgroups (OR = 1.15, OR = 1.09, P < 0.001), while patients with HSV-1(-) & HSV-2( +) infection showed higher risk of and periodontitis only in the subgroup of people aged 40-50 years (OR = 1.10, P = 0.032) and the Mexican-American subgroup (OR = 1.35, P = 0.042). When only severe periodontitis is considered, HSV infection was associated with periodontitis, no matter the patient was infected with either of the virus or both.

CONCLUSIONS

HSV-1 infection was significantly associated with periodontitis and severe periodontitis, while HSV-2 infection was associated with severe periodontitis, and periodontitis in 40-50-year-olds and Mexican-Americans.

Green Alternatives as Antimicrobial Agents in Mitigating Periodontal Diseases: A Narrative Review

Periodontal diseases and dental caries are the most common infectious oral diseases impacting oral health globally. Oral cavity health is crucial for enhancing life quality since it serves as the entranceway to general health. The oral microbiome and oral infectious diseases are strongly correlated. Gram-negative anaerobic bacteria have been associated with periodontal diseases. Due to the shortcomings of several antimicrobial medications frequently applied in dentistry, the lack of resources in developing countries, the prevalence of oral inflammatory conditions, and the rise in bacterial antibiotic resistance, there is a need for reliable, efficient, and affordable alternative solutions for the prevention and treatment of periodontal diseases. Several accessible chemical agents can alter the oral microbiota, although these substances also have unfavorable symptoms such as vomiting, diarrhea, and tooth discoloration. Natural phytochemicals generated from plants that have historically been used as medicines are categorized as prospective alternatives due to the ongoing quest for substitute products. This review concentrated on phytochemicals or herbal extracts that impact periodontal diseases by decreasing the formation of dental biofilms and plaques, preventing the proliferation of oral pathogens, and inhibiting bacterial adhesion to surfaces. Investigations examining the effectiveness and safety of plant-based medicines have also been presented, including those conducted over the past decade.

Antibacterial-Anti-Inflammatory-Bone Restoration Procedure Achieved by MIN-Loaded PLGA Microsphere for Efficient Treatment of Periodontitis

The main development process of periodontitis involves periodontal pathogenic bacteria as the initiating factor causing the onset of destructive inflammation, which in turn stimulates the destruction of periodontal tissue. It is difficult to achieve the eradication of periodontitis due to the complex interaction among antibacterial, anti-inflammatory, and bone restoration. Herein, we propose an antibacterial-anti-inflammatory-bone restoration procedural treatment strategy with minocycline (MIN) for the efficient treatment of periodontitis. In brief, MIN was prepared into PLGA microspheres with tunable release behavior using different species of PLGA, respectively. The optimally selected PLGA microspheres (LA:GA with 50:50, 10 kDa, and carboxyl group) had a drug loading of 16.91%, an in vitro release of approximately 30 days, which also had a particle size of approximately 11.8 µm with a smooth appearance and a rounded morphology. The DSC and XRD results showed that the MIN was completely encapsulated in the microspheres as an amorphous state. Cytotoxicity tests demonstrated the safety and biocompatibility of the microspheres (cell viabilities at a concentration of 1-200 μg/mL were greater than 97%), and in vitro bacterial inhibition tests showed that the selected microspheres could achieve effective bacterial inhibition at the initial stage after administration. The favorable anti-inflammatory (low TNF-α and IL-10 levels) and bone restoration effects (BV/TV: 71.8869%; BMD: 0.9782 g/cm³; TB.Th: 0.1366 mm; Tb.N: 6.9318 mm^-1; Tb.Sp: 0.0735 mm) were achieved in a SD rat periodontitis model after administering once a week for four weeks. The MIN-loaded PLGA microspheres were proved to be an efficient and safe treatment for periodontitis by procedural antibacterial, anti-inflammatory, and bone restoration.

Periodontal microbiology and microbial etiology of periodontal diseases: Historical concepts and contemporary perspectives

This narrative review summarizes the collective knowledge on periodontal microbiology, through a historical timeline that highlights the European contribution in the global field. The etiological concepts on periodontal disease culminate to the ecological plaque hypothesis and its dysbiosis-centered interpretation. Reference is made to anerobic microbiology and to the discovery of select periodontal pathogens and their virulence factors, as well as to biofilms. The evolution of contemporary molecular methods and high-throughput platforms is highlighted in appreciating the breadth and depth of the periodontal microbiome. Finally clinical microbiology is brought into perspective with the contribution of different microbial species in periodontal diagnosis, the combination of microbial and host biomarkers for this purpose, and the use of antimicrobials in the treatment of the disease.

Human Gingival Fibroblast Attachment to Smooth Titanium Disks with Different Surface Roughnesses

Peri-implantitis is a significant problem associated with dental implants. It has been hypothesized that creating a soft-tissue seal around the implant neck prevents peri-implantitis. This study aims to clarify the effects of the surface smoothness of titanium disks on soft tissues. Thus, titanium disks were prepared through electrolytic composite polishing (ECP), sisal buffing (SB), hairline polishing (HP), and laser cutting (LC). The surface roughness values of seven items was measured. For ECP, SB, HP, and LC samples, the Ra values were 0.075, 0.217, 0.671, and 1.024 μm and the Sa values were 0.005, 0.115, 0.500, and 0.676, respectively, indicating that the surface roughness was remarkably lower with ECP. Moreover, the Wsk values for ECP, SB, HP, and LC were 0.521, 1.018, -0.678, and -0.558, respectively. The smooth surfaces produced by ECP and SB were biased toward the concave surface, whereas those produced by HP and LC were biased toward the convex surface. The Rku values for ECP, SB, HP, and LC were 2.984, 11.774, 14.182, and 26.232, respectively. Only the ECP exhibited a moderate bias peak and produced an extremely smooth surface. The contact angles in the cases of ECP, SB, HP, and LC were 60.1°, 66.3°, 68.4°, and 79.3°, respectively, indicating the hydrophobicity of the titanium disks. Human oral fibroblasts were then incubated on each disk for 24 and 48 h to measure cell attachment, and no significant differences were observed. The differences in Ra and Sa did not affect cell attachment. Therefore, by applying ECP to the abutment or implant neck, the cell attachment required for soft-tissue formation while preventing bacterial adhesion can be achieved.

Prevotella species as oral residents and infectious agents with potential impact on systemic conditions

Oral Prevotella are known as anaerobic commensals on oral mucosae and in dental plaques from early life onwards, including pigmented P. melaninogenica, P. nigrescens, and P. pallens and non-pigmented Prevotella species. Many Prevotella species contribute to oral inflammatory processes, being frequent findings in dysbiotic biofilms of periodontal diseases (P. intermedia, P. nigrescens), cariotic lesions (P. denticola, Alloprevotella (formerly Prevotella) tannerae), endodontic infections (P. baroniae, P. oris, P. multisaccharivorax), and other clinically relevant oral conditions. Over the years, several novel species have been recovered from the oral cavity without knowledge of their clinical relevance. Within this wide genus, virulence properties and other characteristics like biofilm formation seemingly vary in a species- and strain-dependent manner, as shown for the P. intermedia group organisms (P. aurantiaca, P. intermedia, P. nigrescens, and P. pallens). Oral Prevotella species are identified in various non-oral infections and chronic pathological conditions. Here, we have updated the knowledge of the genus Prevotella and the role of Prevotella species as residents and infectious agents of the oral cavity, as well as their detection in non-oral infections, but also gathered information on their potential link to cancers of the head and neck, and other systemic disorders.

Models of periodontal disease pathogenesis: A journey through time

Models of pathogenesis help in integrating the data available from current scientific research, which aid in comprehensive understanding of the disease. This stereotypic representation of a disease in the form of a conceptual model helps in translation of new information into practical applications. The evolution in the knowledge of pathogenesis of periodontal disease can lead to a revolution in treatment modalities. The true purpose of pathogenesis models is to highlight the key aspects that need the main focus. Various models of periodontal disease pathogenesis have been proposed based on the prevailing concepts of the disease at that point of time. The aim of the present review is to outline the vital aspects of existing models of periodontal disease pathogenesis.

Evaluating efficacy of a novel dentifrice in reducing probing depths in Stage I and II periodontitis maintenance patients: A randomized, double-blind, positive controlled clinical trial

BACKGROUND

Compliance to periodontal maintenance therapy (PMT) is essential for long-term periodontal health. Between PMT visits, patients must maintain good oral hygiene. A dentifrice with demonstrable clinical benefits for use between PMT visits would be highly desirable. The aim of this clinical study was to investigate the effect of a novel dental gel on probing depths (PD) and inflammation when used as a home care dentifrice in Stage I and II periodontitis patients.

METHODS

This double-blind clinical study randomized 65 subjects with Stage I and II periodontitis to the novel dental gel containing 2.6% EDTA, and a commercially available anti-gingivitis dentifrice with 0.454% stannous fluoride. Primary endpoint was PD at 6 months for those sites with baseline PD ≥ 4 mm and secondary endpoints included whole mouth mean scores of modified gingival index (MGI), modified sulcus bleeding index (mSBI) and plaque index (PI). No SRP was performed at baseline.

RESULTS

Subjects using the novel dentifrice showed significant PD reductions of 1.18 mm (from 4.27 mm at baseline to 3.09 mm at 6 months) compared to 0.93 mm (from 4.23 mm at baseline to 3.30 mm at 6 months) shown for those using the positive control dentifrice. Difference between treatments at 6 months was 0.21 mm with P-value = 0.0126. Significant improvements in MGI (P = 0.0000), mSBI (P = 0.0000), and PI (P = 0.0102) were also observed in 6 months.

CONCLUSION

The novel dentifrice showed significant reductions in PD and gingival inflammation over 6 months solely as a home care dentifrice without baseline SRP in Stage I and II periodontitis maintenance patients.

Erbium-doped: yttrium-aluminum-garnet (Er:YAG) versus scaling and root planing for the treatment of periodontal disease: A single-blinded split-mouth randomized clinical trial

BACKGROUND

This randomized, controlled clinical trial aimed to compare the differences in periodontal clinical outcomes, duration of the procedure, and patient's experience between conventional scaling and root planing and erbium-doped: yttrium-aluminum-garnet (Er:YAG) in the treatment of generalized moderate to severe chronic periodontitis or generalized Stages II or III, and Grade B periodontitis based on the Centers for Disease Control (CDC), American Academy of Periodontology (AAP), and European Federation of Periodontology (EFP) definitions.

METHODS

Thirty subjects were initially recruited. In a split-mouth fashion, right and left sides were randomly allocated into two treatment arms: conventional scaling and root planing (C-SRP) versus laser-assisted scaling and root planing (L-SRP). A blinded examiner recorded clinical measurements at baseline and 3 months. Duration of the procedure was also recorded for each visit, and the patient's experience was assessed with a questionnaire at baseline, 1, and 3 months.

RESULTS

The final sample consisted of 26 subjects. Both treatments resulted in overall improvement, but no significant differences were found between modalities for clinical attachment gain or probing depth reduction. The duration of the procedure was approximately half for L-SRP, and postoperative sensitivity was greater in C-SRP.

CONCLUSIONS

The low-energy protocol with Er:YAG (50 mJ) used for the non-surgical treatment of moderate-severe chronic or Stage II-III, Grade B periodontitis performed in this study population was a treatment modality that yielded similar clinical improvements when compared to conventional scaling and root planing.

Role of Hyalin-like Protein in Gliding and Biofilm Formation by Capnocytophaga Ochracea

Capnocytophaga ochracea possesses a type-IX secretion system that exports proteins which have a gliding motility-associated C-terminal (CTD) domain. This system is found in several species of the Bacteroidetes phylum. Hyalin, a large protein encoded by Coch_0033 in C. ochracea ATCC 27872, has a CTD domain and is posited to be involved in quorum sensing according to the database of the Kyoto Encyclopedia of Genes and Genomes. This suggests that it plays a role in biofilm formation via interbacterial communication. The aim of this study was to investigate the potential role of the hyalin-like protein coded by the Coch_0033 gene in gliding and biofilm formation of C. ochracea. A hyalin-like protein-deficient mutant strain of C. ochracea, designated mutant WR-1, was constructed through insertion of the ermF-ermAM cassette into the target gene. The spreading feature at the edge of the colony was lost in the mutant strain. Crystal violet and confocal laser scanning microscopy revealed no difference between the quantity of biofilm organized by the mutant and that organized by the wild-type strain. These data suggest that the hyalin-like protein encoded by the Coch_0033 gene is indeed involved in C. ochracea gliding activity.

Local drug delivery systems as therapeutic strategies against periodontitis: A systematic review

Periodontitis is a chronic inflammation of the soft tissue surrounding and supporting the teeth, which causes periodontal structural damage, alveolar bone resorption, and even tooth loss. Its prevalence is very high, with nearly 60% of the global population affected. Hence, periodontitis is an important public health concern, and the development of effective healing treatments for oral diseases is a major target of the health sciences. Currently, the application of local drug delivery systems (LDDS) as an adjunctive therapy to scaling and root planning (SRP) in periodontitis is a promising strategy, giving higher efficacy and fewer side effects by controlling drug release. The cornerstone of successful periodontitis therapy is to select an appropriate bioactive agent and route of administration. In this context, this review highlights applications of LDDS with different properties in the treatment of periodontitis with or without systemic diseases, in order to reveal existing challenges and future research directions.

Quantification of Bacteria in Mouth-Rinsing Solution for the Diagnosis of Periodontal Disease

This study aimed to evaluate the feasibility of diagnosing periodontitis via the identification of 18 bacterial species in mouth-rinse samples. Patients (n = 110) who underwent dental examinations in the Department of Periodontology at the Veterans Health Service Medical Center between 2018 and 2019 were included. They were divided into healthy and periodontitis groups. The overall number of bacteria, and those of 18 specific bacteria, were determined via real-time polymerase chain reaction in 92 mouth-rinse samples. Differences between groups were evaluated through logistic regression after adjusting for sex, age, and smoking history. There was a significant difference in the prevalence (healthy vs. periodontitis group) of Aggregatibacter actinomycetemcomitans (2.9% vs. 13.5%), Treponema denticola (42.9% vs. 69.2%), and Prevotella nigrescens (80% vs. 2.7%). Levels of Treponema denticola, Prevotella nigrescens, and Streptococcus mitis were significantly associated with severe periodontitis. We demonstrated the feasibility of detecting periopathogenic bacteria in mouth-rinse samples obtained from patients with periodontitis. As we did not comprehensively assess all periopathogenic bacteria, further studies are required to assess the potential of oral-rinsing solutions to indicate oral infection risk and the need to improve oral hygiene, and to serve as a complementary method for periodontal disease diagnosis.

Compromised Epithelial Cell Attachment after Polishing Titanium Surface and Its Restoration by UV Treatment

Titanium-based implant abutments and tissue bars are polished during the finalization. We hypothesized that polishing degrades the bioactivity of titanium, and, if this is the case, photofunctionalization-grade UV treatment can alleviate the adverse effect. Three groups of titanium disks were prepared; machined surface, polished surface and polished surface followed by UV treatment (polished/UV surface). Polishing was performed by the sequential use of greenstone and silicon rubber burs. UV treatment was performed using a UV device for 12 min. Hydrophobicity/hydrophilicity was examined by the contact angle of ddH₂O. The surface morphology and chemistry of titanium were examined by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. Human epithelium cells were seeded on titanium disks. The number of cells attached, the spreading behavior of cells and the retention on titanium surfaces were examined. The polished surfaces were smooth with only minor scratches, while the machined surfaces showed traces and metal flashes made by machine-turning. The polished surfaces showed a significantly increased percentage of surface carbon compared to machined surfaces. The carbon percentage on polished/UV surfaces was even lower than that on machined surfaces. A silicon element was detected on polished surfaces but not on polished/UV surfaces. Both machined and polished surfaces were hydrophobic, whereas polished/UV surfaces were hydrophilic. The number of attached cells after 24 h of incubation was 60% lower on polished surfaces than on machined surfaces. The number of attached cells on polished/UV surfaces was even higher than that on machined surfaces. The size and perimeter of cells, which was significantly reduced on polished surfaces, were fully restored on polished/UV surfaces. The number of cells remained adherent after mechanical detachment was reduced to half on polished surfaces compared to machined surfaces. The number of adherent cells on polished/UV surfaces was two times higher than on machined surfaces. In conclusion, polishing titanium causes chemical contamination, while smoothing its surface significantly compromised the attachment and retention of human epithelial cells. The UV treatment of polished titanium surfaces reversed these adverse effects and even outperformed the inherent bioactivity of the original titanium.

Clinicomicrobiological evaluation of the efficacy of local delivery of moxifloxacin and ibuprofen gel as an adjunct to scaling and root planing in chronic periodontitis patients

Aims:

To evaluate the clinical and microbiological effects of local drug delivery of moxifloxacin and ibuprofen gel as an adjunct to conventional periodontal therapy in chronic periodontitis patients.

Subjects and Methods:

Twenty patients with moderate-to-severe chronic generalized periodontitis with probing pocket depth (PPD) of ≥5 mm and <8 mm were randomly assigned to one of the following two treatment modalities: scaling and root planing (SRP) group and moxifloxacin and ibuprofen combination gel as an adjunct to SRP group. Clinical parameters include plaque index (PI), gingival index (GI), probing depths and clinical attachment level (CAL) that were recorded at baseline and 1 and 3 months after the treatment, and microbiologic assessment was done using dark-field microscopy.

Results:

A statistically significant difference in mean PI and GI scores and reduction in PPD and gain in CAL were observed at different study intervals with greater difference in the test group. On microbiological examination, the percentage of cocci increased, while a statistically significant decrease in the mean percentage of bacilli and spirochetes was observed in both groups at given intervals. In-vitro dissolution showed controlled release of both the drugs.

Conclusions:

Among the two treatment modalities, treatment with moxifloxacin and ibuprofen local delivery as an adjunct to SRP gave superior results in clinical and microbiological parameters compared to SRP group.

Comparing the Effect of Combination of 1% Ornidazole and 0.25% Chlorhexidine Gluconate (Ornigreat™) Gel and Aloe vera Gel in the Treatment of Chronic Periodontitis: A Randomized, Single-Blind, Split-Mouth Study

Aim and Objective:

The aim of this study is to compare the efficiency of subgingivally delivered 1% ornidazole and 0.25% chlorhexidine (CHX) gluconate (Ornigreat™ gel) and Aloe vera (AV) gel in the treatment of chronic periodontitis.

Materials and Methods:

Twenty chronic periodontitis patients with pocket depths ranging from 4 to 6 mm bilaterally at least in one site were included in the study. After a thorough nonsurgical periodontal therapy, 1% ornidazole and 0.25% CHX gluconate (Ornigreat™ gel) and AV gel were subgingivally delivered into the pocket sites, and the clinical parameters such as plaque index (PI), gingival index (GI), bleeding index (BI), and clinical attachment level (CAL) were evaluated at baseline and after 4 weeks.

Results:

In both the groups, a reduction in PI, GI, and probing depth readings was evidenced after 4 weeks. A significant improvement was noticed in the BI in the AV group when compared with that of Ornigreat™ group. Taking CAL into consideration, though improvement was there in both the groups, it was not appreciable.

Conclusion:

AV which is an herbal derivative when subgingivally delivered in the pocket site could be an equally effective and affordable substitute for Ornigreat™ gel.

Herpesvirus-bacteria synergistic interaction in periodontitis

The etiopathogenesis of severe periodontitis includes herpesvirus-bacteria coinfection. This article evaluates the pathogenicity of herpesviruses (cytomegalovirus and Epstein-Barr virus) and periodontopathic bacteria (Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis) and coinfection of these infectious agents in the initiation and progression of periodontitis. Cytomegalovirus and A. actinomycetemcomitans/P. gingivalis exercise synergistic pathogenicity in the development of localized ("aggressive") juvenile periodontitis. Cytomegalovirus and Epstein-Barr virus are associated with P. gingivalis in adult types of periodontitis. Periodontal herpesviruses that enter the general circulation may also contribute to disease development in various organ systems. A 2-way interaction is likely to occur between periodontal herpesviruses and periodontopathic bacteria, with herpesviruses promoting bacterial upgrowth, and bacterial factors reactivating latent herpesviruses. Bacterial-induced gingivitis may facilitate herpesvirus colonization of the periodontium, and herpesvirus infections may impede the antibacterial host defense and alter periodontal cells to predispose for bacterial adherence and invasion. Herpesvirus-bacteria synergistic interactions, are likely to comprise an important pathogenic determinant of aggressive periodontitis. However, mechanistic investigations into the molecular and cellular interaction between periodontal herpesviruses and bacteria are still scarce. Herpesvirus-bacteria coinfection studies may yield significant new discoveries of pathogenic determinants, and drug and vaccine targets to minimize or prevent periodontitis and periodontitis-related systemic diseases.

Periodontal herpesvirus morbidity and treatment

Four billion individuals worldwide have a history of periodontitis, with the poorest people in society most affected. Periodontitis can lead to unsightly drifting of teeth and tooth loss that may interfere with the wellbeing of daily living and has also been linked to at least 57 medical diseases and disabilities. The etiology of severe periodontitis includes active herpesviruses, specific bacterial pathogens, and destructive immune responses, but herpesviruses seem to be the major pathogenic determinant. Periodontal herpesviruses that disseminate via the systemic circulation to nonoral sites may represent a major link between periodontitis and systemic diseases. Current treatment of periodontitis focuses almost exclusively on bacterial biofilm and will require revision. Periodontal therapy that targets both herpesviruses and bacterial pathogens can provide long-term clinical improvement and potentially reduces the risk of systemic diseases. Molecular diagnostic tests for periodontal pathogens may enable early microbial identification and preemptive therapy. This review details an efficient and reliable anti-infective treatment of severe periodontitis that can be carried out in minimal time with minimal cost.

Importance of Virulence Factors for the Persistence of Oral Bacteria in the Inflamed Gingival Crevice and in the Pathogenesis of Periodontal Disease

Periodontitis is a chronic inflammation that develops due to a destructive tissue response to prolonged inflammation and a disturbed homeostasis (dysbiosis) in the interplay between the microorganisms of the dental biofilm and the host. The infectious nature of the microbes associated with periodontitis is unclear, as is the role of specific bacterial species and virulence factors that interfere with the host defense and tissue repair. This review highlights the impact of classical virulence factors, such as exotoxins, endotoxins, fimbriae and capsule, but also aims to emphasize the often-neglected cascade of metabolic products (e.g., those generated by anaerobic and proteolytic metabolism) that are produced by the bacterial phenotypes that survive and thrive in deep, inflamed periodontal pockets. This metabolic activity of the microbes aggravates the inflammatory response from a low-grade physiologic (homeostatic) inflammation (i.e., gingivitis) into more destructive or tissue remodeling processes in periodontitis. That bacteria associated with periodontitis are linked with a number of systemic diseases of importance in clinical medicine is highlighted and exemplified with rheumatoid arthritis, The unclear significance of a number of potential "virulence factors" that contribute to the pathogenicity of specific bacterial species in the complex biofilm-host interaction clinically is discussed in this review.

Evaluation and Comparison of Antibacterial Efficacy of Herbal Extracts in Combination with Antibiotics on Periodontal pathobionts: An in vitro Microbiological Study

BACKGROUND

In the past few decades focus of research has been toward herbal medicines because of growing bacterial resistance and side effects of antimicrobial agents. The extract derived from the plants may increase the efficacy of antibiotics when used in combination against pathogenic bacteria. In the current study, the synergistic antibacterial efficacy of plant extracts in combination with antibiotics has been assessed on selected periodontal pathogens.

METHODS

Ethanolic extracts were prepared from Salvadora persica (Miswak) and Cinnamomum zeylanicum (Ceylon cinnamon), by the soxhalate method. Plaque samples were collected from clinical periodontitis patients to isolate and grow the periodontal pathobionts under favorable conditions. Susceptibility of bacteria to the extracts was assessed by gauging the diameter of the inhibition zones. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of plant extracts were determined against each bacterium. Synergistic activity of plants extract in combination with antibiotics against the bacteria was also assessed by measuring the diameter of the inhibition zones.

RESULTS

Ethanolic extract of both the plants showed an inhibitory effect on the proliferation and growth of all four strains of periodontal pathobionts. Maximum antibacterial activity was exhibited by C. zeylanicum against Tannerella forsythia (MIC = 1.56 ± 0.24 mg/mL, MBC = 6.25 ± 0.68 mg/mL), whereas among all the studied groups the minimum activity was reported by C. zeylanicum against Aggregatibacter actinomycetemcomitans the (MIC = 12.5 ± 3.25 mg/mL, MBC = 75 ± 8.23 mg/mL). Combination of herbal extracts with different antibiotics revealed a synergistic antibacterial effect. The best synergism was exhibited by S. persica with metronidazole against A. actinomycetemcomitans (27 ± 1.78).

CONCLUSIONS

Current in vitro study showed variable antibacterial activity by experimented herbal extracts against periodontal pathobionts. The synergistic test showed significant antibacterial activity when plant extracts were combined with antibiotics.

Selective growth inhibition of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans by antisense peptide nucleic acids

Peptide nucleic acids (PNA) are DNA/RNA analogs in which the sugar-phosphate backbone is replaced by N-2-aminoethylglycine. PNA are widely used for experimental antisense therapy due to their strong affinity to mRNA. By targeting specific genes, protein synthesis and the growth of bacteria or cancer cells can be inhibited by PNA. Here, we report the design and evaluation of antisense PNA for selective growth inhibition of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, potent pathogens associated with periodontitis. Antisense PNA against groEL and acpP were prepared with carrier peptide (KFFKFFKFFK). Anti-groEL PNA for P. gingivalis specifically inhibited growth in a dose-dependent manner, and growth was inhibited for 5 h at a concentration of 3 μM. Anti-groEL PNA for A. actinomycetemcomitans inhibited growth for 2 h at a concentration of 3 μM with reduced GroEL protein expression. Anti-acpP PNA did not show a marked growth inhibitory effect on either species. Although further studies are needed to develop more effective antisense PNA for both species, anti-groEL PNA may be potentially useful species-specific antibacterial tools against oral pathogens.

Thermal Magnetic Field Activated Propolis Release From Liquid Crystalline System Based on Magnetic Nanoparticles

Intra-periodontal pocket drug delivery systems, such as liquid crystalline systems, are widely utilized improving the drug release control and the therapy. Propolis is used in the treatment of periodontal diseases, reducing the inflammatory and infectious conditions. Iron oxide magnetic nanoparticles (MNPs) can improve the treatment when an alternating external magnetic field (AEMF) is applied, increasing the local temperature. The aim of this study was to develop a liquid crystalline system containing MNPs for intra-periodontal pocket propolis release. MNPs were prepared using iron salts and the morphological, size, thermal, x-ray diffraction, magnetometry, and Mössbauer spectroscopy analyses were performed. Cytotoxicity studies using Artemia salina and fibroblasts were also accomplished. The systems were prepared using polyoxyethylene (10) oleyl ether, isopropyl myristate, purified water, and characterized by polarized optical microscopy, rheometry, and in vitro drug release profile using a periodontal pocket simulator apparatus. The antifungal activity of the systems was investigated against Candida spp. using an AEMF. MNPs displayed nanometric size, were monodisperse, and they displayed very low cytotoxicity. Microscopically homogeneous formulations were obtained displaying important physicochemical and biological properties. The system displayed prolonged release of propolis and important in vitro fungicide activity, which was increased when the AEMF was applied, indicating a potentially alternative therapy for the treatment of the periodontal disease.

Comparison of Oral Microbe Quantities from Tongue Samples and Subgingival Pockets

Objectives

To improve understanding of periodontitis pathology, we need more profound knowledge of relative abundances of single prokaryotic species and colonization dynamics between habitats. Thus, we quantified oral microbes from two oral habitats to gain insights into colonization variability and correlation to the clinical periodontal status.

Methods

We analyzed tongue scrapings and subgingival pocket samples from 237 subjects (35–54 years) with at least 10 teeth and no recent periodontal treatment from the 11-year follow-up of the Study of Health in Pomerania. Relative abundances of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Streptococcus sanguinis, total bacteria, and Archaea were correlated to clinically assessed pocket depths (PD) and clinical attachment levels (CAL).

Results

Increased relative abundances of P. gingivalis, A. actinomycetemcomitans, and F. nucleatum were linked to increased levels of PD and CAL (i) on the subject level (mean PD, mean CAL) and (ii) in subgingival pockets. Relative abundances of Archaea from tongue samples correlated negatively with mean PD or mean CAL. Detection and quantity of bacterial species correlated weakly to moderately between the tongue and subgingival pocket, except for Archaea.

Conclusions

Relative abundances of specific oral species correlated weakly to moderately between habitats. Single species, total bacteria, and Archaea were linked to clinically assessed severity of periodontitis in a habitat-dependent manner.

Role of oral and gut microbiome in nitric oxide-mediated colon motility

Periodontal disease (PD), a severe form of gum disease, is among the most prevalent chronic infection in humans and is associated with complex microbial synergistic dysbiosis in the subgingival cavity. The immune system of the body interacts with the microbes as the plaque extends and propagates below the gingival sulcus. Once bacteria reach the gingival sulcus, it can enter the blood stream and affect various areas of the human body. The polymicrobial nature of periodontal disease, if left untreated, promotes chronic inflammation, not only within the oral cavity, but also throughout the human body. Alterations seen in the concentrations of healthy gut microbiota may lead to systemic alterations, such as gut motility disorders, high blood pressure, and atherosclerosis. Although gut microbiome has been shown to play a vital role in intestinal motility functions, the role of oral bacteria in this setting remains to be investigated. It is unclear whether oral microbial DNA is present in the large intestine and, if so, whether it alters the gut microbiome. In addition, polybacterial infection induced PD reduced nitric oxide (NO) synthesis and antioxidant enzymes in rodent colon. In this review, we will discuss the interactions between oral and gut microbiome, specifics of how the oral microbiome may modulate the activities of the gut microbiome, and possible ramifications of these alterations.

Black-pigmented anaerobic bacteria associated with ovine periodontitis

Periodontitis is a polymicrobial infectious disease that causes occlusion change, tooth loss, difficulty in rumination, and premature culling of animals. This study aimed to detect species of the genera Porphyromonas and Prevotella present in the periodontal pocket of sheep with lesions deeper than 5mm (n=14) and in the gingival sulcus of animals considered periodontally healthy (n=20). The presence of microorganisms was evaluated by polymerase chain reaction (PCR) using specific primers for Porphyromonas asaccharolytica, Porphyromonas endodontalis, Porphyromonas gingivalis, Porphyromonas gulae, Prevotella buccae, Prevotella intermedia, Prevotella loescheii, Prevotella melaninogenica, Prevotella nigrescens, Prevotella oralis, and Prevotella tannerae. Prevalence and risk analysis were performed using Student's t-test and Spearman's correlation. Among the Prevotella and Porphyromonas species detected in the periodontal lesions of sheep, P. melaninogenica (85.7%), P. buccae (64.3%), P. gingivalis (50%), and P. endodontalis (50%) were most prevalent. P. gingivalis (15%) and P. oralis (10%) prevailed in the gingival sulcus. P. gulae and P. tannerae were not detected in the 34 samples studied. Data evaluation by t-test verified that occurrence of P. asaccharolytica, P. endodontalis, P. gingivalis, P. buccae, P. intermedia, P. melalinogenica, and P. nigrescens correlated with sheep periodontitis. The findings of this study will be an important contribution to research on pathogenesis of sheep periodontitis and development of its control measures.

The risk reduction of recurrent periodontal pathogens of local application minocycline HCl 2% gel, used as an adjunct to scaling and root planing for chronic periodontitis treatment

Background

The aim of this study was to evaluate the clinical and microbiological effects of local application minocycline HCl 2% gel, used as an adjunct to scaling and root planing (SRP) for treatment of chronic periodontitis (CP). CP is an inflammation of periodontal tissue that is caused mainly by bacterial infection, where periodontal destruction such as loss of attachment and bone destruction occurred.

Methods

A total of 81 subjects with moderate to severe periodontitis whose baseline clinical attachment loss (CAL) was ≥4 mm were randomly assigned to receive SRP alone (control group, N=39) or SRP followed by four times of local application of minocycline HCl gel (Periocline) once a week (test group, N=42). Pocket depth, CAL, and papilla bleeding index were examined at baseline, 21 days, 2, 3, and 6 months. Subgingival plaque samples were collected with sterile curettes and were analyzed by real-time polymerase chain reaction for the presence of three periodontal pathogens (Porphyromonas gingivalis [P.g.], Tannerella forsythia [T.f.], and Treponema denticola [T.d.]) at baseline, 2, 3, and 6 months.

Results

The number of bacteria was reduced in both groups at 2 months after baseline (SRP treatment). The changes (2–6 months) in T.d. and T.f. counts in the test group were significantly lower than those in the control group. In the control group, a significant regrowth of P.g., T.f., and T.d. was observed from 2 to 6 months and of P.g. and T.f. from 3 to 6 months. On the other hand, in the test group, the number of the three bacteria did not significantly increase during the 6-month period.

Conclusion

The results showed that local application of minocycline, used as an adjunct to SRP, was effective for suppressing regrowth of periodontal pathogens, suggesting its risk reduction of recurrent periodontal pathogens in CP.

Heterogeneity of Surfaces of Subgingival Bacteria as Detected by Zeta Potential Measurements

Porphyromonasgingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans (A.a.) are Gram-negative bacteria which are implicated in various forms of periodontal disease. The Gram-positive Peptostreptococcus micros may also play an important role. For investigation of the possible adhesion and colonization mechanisms of these organisms, the charge properties of the outermost layers of bacterial cell surfaces were studied through the measurement of zeta potentials at various pH values. Eleven fresh clinical isolates, representing the four species, and one laboratory strain, P. gingivalis W83, were examined. Eleven of the 12 strains displayed heterogeneity with respect to pH-dependent zeta potentials. Within single cultures of each of these strains, two distinct populations of cells were found, one which was more negatively charged than the other. For the Gram-negative strains, the more negatively charged subpopulation was in the majority, while the P. micros strains appeared to be composed mainly of a less-negatively-charged subpopulation. Vesicles prepared from two strains displayed the same pH dependence and heterogeneity of zeta potentials as the parent cells. An A.a. strain which was passaged several times in fluid medium had lost its fimbriae and became homogeneous with respect to charge.

Comparative efficacy of aloe vera mouthwash and chlorhexidine on periodontal health: A randomized controlled trial

Background

With introduction of many herbal medicines, dentistry has recently evidenced shift of approach for treating many inflammatory oral diseases by using such modalities. Aloe vera is one such product exhibiting multiple benefits and has gained considerable importance in clinical research recently.

Aim

To compare the efficacy of Aloevera and Chlorhexidine mouthwash on Periodontal Health.

Material and Methods

Thirty days randomized controlled trial was conducted among 390 dental students. The students were randomized into two intervention groups namely Aloe Vera (AV) chlorhexidine group (CHX) and one control (placebo) group. Plaque index and gingival index was recorded for each participant at baseline, 15 days and 30 days. The findings were than statistically analyzed, ANOVA and Post Hoc test were used.

Results

There was significant reduction (p<0.05) in the mean scores of all the parameters with Aloe Vera (AV) and chlorhexidine group. Post hoc test showed significant difference (p<0.000) in mean plaque and gingival index scores of aloe Vera and placebo and chlorhexidine and placebo group. No significant difference (p<0.05) was observed between AloeVera and chlorhexidine group.

Conclusions

Being an herbal product AloeVera has shown equal effectiveness as Chlorhexidine. Hence can be used as an alternative product for curing and preventing gingivitis.

Key words:Aloe vera, chlorhexidine, dental plaque, gingivitis.

Pro-atherogenic properties of lipopolysaccharide from the periodontal pathogen Actinobacillus actinomycetemcomitans

An association between cardiovascular and periodontal disease may be due to lipopolysaccharide (LPS)-promoted release of inflammatory mediators, adverse alterations of the lipoprotein profile, and an imbalance in cholesterol homeostasis. Since periodontopathogenic potential differs between serotypes of a major periodontal pathogen, Actinobacillus actinomycetemcomitans, we studied the pro-atherogenic properties of LPS preparations from serotypes b and d strains on macrophages (RAW 264.7). A. actinomycetemcomitans LPS preparations induced a time-dependent release of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). LPS induced foam cell formation and cholesteryl ester accumulation from native low density lipoprotein in the following order: A. actinomycetemcomitans strains JP2 (serotype b) > Y4 (serotype b) > IDH781 (serotype d). mRNA expression levels of scavenger receptor class B, type-I, and ATP-binding cassette transporter-1, receptors mediating cholesterol efflux from macrophages, were decreased by LPS preparations. The results suggest that the pro-atherogenic potential of A. actinomycetemcomitans LPS may depend on the infecting strain and correlate with the periodontopathogenic potential of the pathogen.

Endothelial Cell Response to Fusobacterium nucleatum

Vascular response is an essential aspect of an effective immune response to periodontal disease pathogens, as new blood vessel formation contributes to wound healing and inflammation. Gaining a greater understanding of the factors that affect vascular response may then contribute to future breakthroughs in dental medicine. In this study, we have characterized the endothelial cell response to the common bacterium Fusobacterium nucleatum, an important bridging species that facilitates the activity of late colonizers of the dental biofilm. Endothelial cells were infected with Fusobacterium nucleatum (strain 25586) for periods of 4, 12, 24, or 48 h. Cell proliferation and tube formation were analyzed, and expression of adhesion molecules (CD31 and CD34) and vascular endothelial growth factor (VEGF) receptors 1 and 2 was measured by fluorescence-activated cell sorter (FACS) analysis. Data indicate that F. nucleatum impaired endothelial cell proliferation and tube formation. The findings suggest that the modified endothelial cell response acts as a mechanism promoting the pathogenic progression of periodontal diseases and may potentially suggest the involvement of periodontopathogens in systemic diseases associated with periodontal inflammation.

Adjunctive use of essential oils following scaling and root planing -a randomized clinical trial

BACKGROUND

Hitherto no study has been published on the effect of the adjunctive administration of essential oils following scaling and root planing (SRP). This study describes the effect of a mouthrinse consisting of essential oils (Cymbopogon flexuosus, Thymus zygis and Rosmarinus officinalis) following SRP by clinical and microbiological variables in patients with generalized moderate chronic periodontitis.

METHODS

Forty-six patients (aged 40-65 years) with moderate chronic periodontitis were randomized in a double-blind study and rinsed their oral cavity following SRP with an essential oil mouthrinse (n  =  23) or placebo (n  =  23) for 14 days. Probing depth (PD), attachment level (AL), bleeding on probing (BOP) and modified sulcus bleeding index (SBI) were recorded at baseline and after 3 and 6 months. Subgingival plaque was taken for assessment of major bacteria associated with periodontitis.

RESULTS

AL, PD, BOP and SBI were significantly improved in both groups after three (p   <   0.001) and 6 months (p   ≤   0.015). AL improved significantly better in the test than in the control group after 3 and 6 months (p < 0.001), so did PD after three months in the tendency (p  =  0.1). BOP improved better in the test group after 3 months (p  =  0.065). Numbers of Treponema denticola (p  =  0.044) and Fusobacterium nucleatum (p  =  0.029) decreased more in the test than in the control group after 3 months, those of Tannerella forsythia after 6 months (p  =  0.039). Prevotella micra (p  <  0.001, p  =  0.035) and Campylobacter rectus (p  =  0.002 , p  =  0.012) decreased significantly in both groups after 3 months.

CONCLUSIONS

The adjunctive use of a mouthrinse containing essential oils following SRP has a positive effect on clinical variables and on bacterial levels in the subgingival biofilm.

TRIAL REGISTRATION

332-12-24092012, DRKS 00009387, German Clinical Trials Register, Freiburg i. Br., 16.09.2015.

Effects of triclosan on host response and microbial biomarkers during experimental gingivitis

AIM

This exploratory randomized, controlled clinical trial sought to evaluate anti-inflammatory and -microbial effects of triclosan during experimental gingivitis as assessed by host response biomarkers and biofilm microbial pathogens.

MATERIALS AND METHODS

Thirty participants were randomized to triclosan or control dentifrice groups who ceased homecare for 21 days in an experimental gingivitis (EG) protocol. Plaque and gingival indices and saliva, plaque, and gingival crevicular fluid (GCF) were assessed/collected at days 0, 14, 21 and 35. Levels and proportions of 40 bacterial species from plaque samples were determined using checkerboard DNA-DNA hybridization. Ten biomarkers associated with inflammation, matrix degradation, and host protection were measured from GCF and saliva and analysed using a multiplex array. Participants were stratified as "high" or "low" responders based on gingival index and GCF biomarkers and bacterial biofilm were combined to generate receiver operating characteristic curves and predict gingivitis susceptibility.

RESULTS

No differences in mean PI and GI values were observed between groups and non-significant trends of reduction of host response biomarkers with triclosan treatment. Triclosan significantly reduced levels of A. actinomycetemcomitans and P. gingivalis during induction of gingivitis.

CONCLUSIONS

Triclosan reduced microbial levels during gingivitis development (ClinicalTrials.gov NCT01799226).

Potent In Vitro and In Vivo Activity of Plantibody Specific for Porphyromonas gingivalis FimA

Fimbrial protein fimbrillin (FimA), a major structural subunit of Porphyromonas gingivalis, has been suggested as a vaccine candidate to control P. gingivalis-induced periodontal disease. Previously, cDNAs encoding IgG monoclonal antibodies (MAbs) against purified FimA from P. gingivalis 2561 have been cloned, and the MAbs have been produced in rice cell suspension. Here we examined the biological activities of the plant-produced MAb specific for FimA (anti-FimA plantibody) of P. gingivalis in vitro and in vivo. The anti-FimA plantibody recognized oligomeric/polymeric forms of native FimA in immunoblot analysis and showed high affinity for native FimA (KD = 0.11 nM). Binding of P. gingivalis (10(8) cells) to 2 mg of saliva-coated hydroxyapatite beads was reduced by 53.8% in the presence of 1 μg/ml plantibody. Anti-FimA plantibody (10 μg/ml) reduced invasion of periodontal ligament cells by P. gingivalis (multiplicity of infection, 100) by 68.3%. Intracellular killing of P. gingivalis opsonized with the anti-FimA plantibody by mouse macrophages was significantly increased (77.1%) compared to killing of bacterial cells with irrelevant IgG (36.7%). In a mouse subcutaneous chamber model, the number of recoverable P. gingivalis cells from the chamber fluid was significantly reduced when the numbers of bacterial cells opsonized with anti-FimA plantibody were compared with the numbers of bacterial cells with irrelevant IgG, 66.7% and 37.1%, respectively. These in vitro and in vivo effects of anti-FimA plantibody were comparable to those of the parental MAb. Further studies with P. gingivalis strains with different types of fimbriae are needed to investigate the usefulness of anti-FimA plantibody for passive immunization to control P. gingivalis-induced periodontal disease.

Involvement of the Type IX Secretion System in Capnocytophaga ochracea Gliding Motility and Biofilm Formation

Capnocytophaga ochracea is a Gram-negative, rod-shaped bacterium that demonstrates gliding motility when cultured on solid agar surfaces. C. ochracea possesses the ability to form biofilms; however, factors involved in biofilm formation by this bacterium are unclear. A type IX secretion system (T9SS) in Flavobacterium johnsoniae was shown to be involved in the transport of proteins (e.g., several adhesins) to the cell surface. Genes orthologous to those encoding T9SS proteins in F. johnsoniae have been identified in the genome of C. ochracea; therefore, the T9SS may be involved in biofilm formation by C. ochracea. Here we constructed three ortholog-deficient C. ochracea mutants lacking sprB (which encodes a gliding motility adhesin) or gldK or sprT (which encode T9SS proteins in F. johnsoniae). Gliding motility was lost in each mutant, suggesting that, in C. ochracea, the proteins encoded by sprB, gldK, and sprT are necessary for gliding motility, and SprB is transported to the cell surface by the T9SS. For the ΔgldK, ΔsprT, and ΔsprB strains, the amounts of crystal violet-associated biofilm, relative to wild-type values, were 49%, 34%, and 65%, respectively, at 48 h. Confocal laser scanning and scanning electron microscopy revealed that the biofilms formed by wild-type C. ochracea were denser and bacterial cells were closer together than in those formed by the mutant strains. Together, these results indicate that proteins exported by the T9SS are key elements of the gliding motility and biofilm formation of C. ochracea.

Comparative evaluation of efficacy of three treatment modalities - tetracycline fibers, scaling and root planing, and combination therapy: A clinical study

Background

Tetracycline is one of the primary antibiotics prescribed for antimicrobial therapy in periodontics. It has a broad spectrum of activity being effective against most bacteria as well as spirochetes. Due to limitations of systemic drug therapy, recent formulations of the drug for local administration in the subgingival area have been introduced, including collagen fibers impregnated with tetracycline.

Aims and Objective

To compare the effectiveness of tetracycline fibers alone or in combination with scaling and root planing (SRP) on clinical parameters in chronic periodontitis patients.

Materials and Methods

A total of twenty patients comprising of both sexes in the age group of 35-60 years with chronic periodontitis were selected. Split-mouth design was used, and three teeth from each patient with periodontal pocket measuring > 5 mm were selected which were treated with different treatment modality. They were randomly divided into site A (SRP), site B (tetracycline fibers only), and site C (combination therapy). Clinical parameters of plaque index (PI), gingival index (GI), pocket probing depth, and clinical attachment level (CAL) were recorded at 0, 30, and 45 days. The data obtained was compiled and put to statistical analysis.

Results

All the three groups showed improvement in PI, GI, probing pocket depth, and CAL. Results of the study showed greater improvements in clinical parameters in Group C compared to Group A and Group B.

Conclusion

The results indicate that the adjunctive use of tetracycline fibers with SRP is a clinically effective and simple nonsurgical treatment method to improve periodontal health.

Presence of Porphyromonas and Prevotella species in the oral microflora of cattle with periodontitis

Abstratc: Bovine periodontitis is a progressive purulent infectious process associated with the presence of strictly and facultative anaerobic subgingival biofilm and epidemiologically related to soil management in large geographic areas of Brazil. This study aimed to detect species of the genera Porphyromonas and Prevotella, which occurr in periodontal pockets of cattle with lesions deeper than 5mm (n=26) and in gingival sulcus of animals considered periodontally healthy (n=25). Presence of the microorganisms was evaluated by independent-culture medium diagnostic method, using polymerase chain reaction (PCR) with specific primers of Porphyromonas asaccharolytica, P. endodontalis, P. gingivalis, P. gulae, Prevotella buccae, P. intermedia, P. loescheii, P. melaninogenica, P. nigrescens, P. oralis and P. tannerae. The species P. endodontalis (80.7%), P. melaninogenica (73.1%) and P. intermedia (61.5%) were the most predominant in samples of cattle with periodontitis. Regarding non-injured gingival sulcus of cattle, P. endodontalis (40%) and P. loeschei (40%) prevailed. Porphyromonas gingivalis, P. gulae and Prevotella tannerae were not detected in the 51 samples studied. Data evaluation by T test, enabled to verify that ocorrence of Porphyromonas asaccharolytica (p=0.000003), P. endodontalis (p=0.0023), Prevotella buccae (p=0.0017), P. intermedia (p=0.0020), P. melaninogenica (p=0.00006) and P. oralis (p=0.0028) is correlated with bovine periodontitis.

Efficacy versus health risks: An in vitro evaluation of power-driven scalers

Background:

Power-driven instrumentation of root surfaces during supportive periodontal therapy is an alternative to hand instrumentation. The purpose of this pilot in vitro study was to investigate the efficacy of sub- and supragingival plaque removal with a sonic (AIR: Synea, W and H, Bürmoos, Austria) and two ultrasonic devices (TIG: Tigon+, W and H, Bürmoos, Austria; VEC: Vector, Dürr, Bietigheim-Bissingen, Germany) as well as the health-risk for dental professionals during treatment.

Materials and Methods:

The power-driven devices were utilized to remove plaque from model teeth in dummy heads. The percentage of residual artificial plaque after 2 min of supra- or subgingival instrumentation was calculated by means of image-processing techniques at four sites (n = 576) of each tooth. The Health-Risk-Index (HRI: spatter/residual plaque quotient) with the different power-driven devices was assessed during treatment.

Results:

The smallest amounts of residual plaque were found for the sonic device AIR (8.89% ± 10.92%) and the ultrasonic scaler TIG (8.72% ± 12.02%) (P = 0.707). Significantly more plaque was remained after the use of the ultrasonic scaler VEC (18.76% ± 18.07%) (P < 0.001). Irrespectively of the scaler, efficacy was similar sub- (10.7% ± 11.6%) and supragingivally (13.5% ± 17.2%) (P = 0.901). AIR/TIG demonstrated equal residual amounts of plaque sub- (P = 0.831) as well as supragingivally (P = 0.510). However, AIR/VEC and TIG/VEC were significantly in favor of AIR and TIG (P < 0.001). In contrast, the lowest HRI was found after using VEC (0.0043) and differed considerably for AIR (0.2812) and TIG (0.0287).

Conclusion:

Sonic devices are as effective as ultrasonic devices in the removal of biofilm but bear a higher risk to the dental professional's health concerning the formation of spatter.

Novel Coating of Surgical Suture Confers Antimicrobial Activity Against Porphyromonas gingivalis and Enterococcus faecalis

BACKGROUND

The oral cavity is colonized by >10(9) bacteria, many of which can increase heart disease risk when seeded into the bloodstream. Most dentoalveolar surgeries require the use of surgical sutures. Suture placement and removal can increase the risk of postoperative infection and bacteremia. The aim of this study is to evaluate the antimicrobial activity of a novel quaternary ammonium compound, K21, when coated on different suture materials.

METHODS

The periodontal pathogen Porphyromonas gingivalis and the endodontic species Enterococcus faecalis were grown to early log phase and inoculated on enriched Brucella blood agar, on which were placed identical lengths of surgical suture (chromic gut, polyester suture, silk, and nylon suture) and control unwaxed dental floss impregnated with K21 at 5%, 10%, 20%, and 25% volume/volume in ethanol vehicle. Controls included the following: 1) sutures treated with vehicle; 2) untreated sutures; and 3) unwaxed floss. Zones of inhibition in millimeters were measured at five randomized sites per suture/floss for each concentration and material used. Mean ± SD of zones of inhibition were calculated, and analysis of variance (P <0.05) was used to determine whether differences were statistically significant.

RESULTS

The results indicate that K21-coated suture at concentrations ranging from 5% to 25%, depending on the type of suture, have antimicrobial activity for P. gingivalis and E. faecalis. Nylon suture coated with K21 at 5%, 10%, 20%, and 25% resulted in zones ranging from 3 to 11 mm. Polyester suture was more effective at lower K21 concentrations with 5% (P = 0.0031), 10% (P = 0.0011), and 20% (P = 0.0002), yielding 7.5, 8.3, and 10.5 mm zones of inhibition. K21-coated silk suture yielded significant zones of inhibition at 25% (P <0.0001), whereas chromic gut was effective at K21 concentrations of 5% (P = 0.0081) and 25% (P <0.0001).

CONCLUSION

It is concluded that K21-coated surgical sutures have antimicrobial activity for bacterial species of direct relevance to postoperative infection and bacteremia.

Efficacy of irrigation with different antimicrobial agents on periodontal health in patients treated for chronic periodontitis: A randomized controlled clinical trial

Introduction:

Periodontitis is inflammation of supporting tooth structure. Most individuals get affected by this disease if oral hygiene is not maintained. There are various mechanical and chemical methods for oral hygiene maintenance. In recent past, interest has been diverted toward the herbal/traditional product in oral hygiene maintenance as they are free from untoward effect.

Aim:

To assess the efficacy of subgingival irrigation with herbal extract (HE) as compared with 0.2% chlorhexidine (CHX) on periodontal health in patients who have been treated for chronic periodontitis, and still have residual pocket of 3–5 mm.

Materials and Methods:

This was a controlled, single-blind, randomized study for 3 months. Patients were allocated in two groups (n = 15 each): (1) 0.2% CHX (control group); (2) HE consisting of Punica granatum Linn. (pomegranate), Piper nigrum Linn. (black pepper), and detoxified copper sulfate (test group). Solutions were used for the irrigation using pulsated irrigating device, WaterPik. Clinical outcomes evaluated were plaque index (PI), sulcus bleeding index (SBI), probing depth at baseline, 15^th, 30^th, 60^th, and 90^th day. Microbiologic evaluation was done at baseline and 90^th day.

Results:

Significant reduction in PI was seen in the group of irrigation with HE. While comparing SBI, irrigation with CHX shows a better result. Other parameters such as probing pocket depth and microbiological counting were similar for both groups.

Conclusion:

Irrigation with HE is a simple, safe, and noninvasive technique with no serious adverse effects. It also reduces the percentage of microorganism in periodontal pocket.