Dental Plaque Bacteria Research Articles

Phytocompounds vs. Dental Plaque Bacteria: In vitro Effects of Myrtle and Pomegranate Polyphenolic Extracts Against Single-Species and Multispecies Oral Biofilms.

In the last decades, resistant microbial infection rate has dramatically increased, especially infections due to biofilm-producing strains that require increasingly complex treatments and are responsible for the increased mortality percentages compared with other infectious diseases. Considering that biofilms represent a key factor for a wide range of chronic infections with high drug tolerance, the treatment of biofilm-causing bacterial infections represents a great challenge for the future. Among new alternative strategies to conventional antimicrobial agents, the scientific interest has shifted to the study of biologically active compounds from plant-related extracts with known antimicrobial properties, in order to also evaluate their antibiofilm activity. In this regard, the aim of this study has been to assess the antibiofilm activity of polyphenolic extracts from myrtle leaf and pomegranate peel against oral pathogens of dental plaque, an excellent polymicrobial biofilm model. In particular, the in vitro antibiofilm properties of myrtle and pomegranate extracts, also in binary combination, were highlighted. In addition to inhibiting the biofilm formation, the tested polyphenolic extracts have been proven to destroy both preformed single-species and multispecies biofilms formed by Streptococcus mutans, Streptococcus oralis, Streptococcus mitis, and Rothia dentocariosa oral isolates, suggesting that the new natural sources are rich in promising compounds able to counteract biofilm-related infections.

English

BACKGROUND Odontogenic infections are recognized as one of the most common diseases in the world. Organisms that cause dental infection and are a part of the oral normal flora include dental plaque bacteria, mucosal surface bacteria, and gingival bacteria. This study aimed to investigate the prevalence of odontogenic infections by involving the facial and cervical spaces in patients referred to Shahid Rahnemoon Hospital from 2014 to 2018. METHODS This was a descriptive cross-sectional study. The sampling method was census and 308 patients with all types of odontogenic infections associated with the involvement of the facial and cervical spaces referred to Shahid Rahnemoon Hospital from 2014 to 2018 were included in the study. Questionnaire was used for data collection. The data was entered into SPSS version 23 software and analysed using statistical tests. RESULTS The mean age of participants was 31.10 ± 14.48; the mean number of hospitalization days was 4.83 ± 2.52 days; the mean body temperature was 37.45 ± 0.54. Of the 308 patients studied, 221 (71.8 %) had no history of systemic disease. Also, 294 (5 %) had no airway involvement. The most commonly prescribed antibiotic was penicillin + metronidazole with a frequency of 54.9 %, The most common tooth that was the source of infection was mandibular tooth no. 6 with a frequency of 22.7 %, the most common type of treatment was incision + drainage + antibiotic therapy with a frequency of 44.2 %; the most common involved area was the submandibular + buccal space with a frequency of 20.1 % and the most common age range of involvement was 20 - 29 years. CONCLUSIONS In odontogenic infections, penicillin + metronidazole is the most commonly used antibiotic and buccal + submandibular space is the most common area involved. KEY WORDS Odontogenic Infection, Facial Spaces, Cervical Spaces

Cannabinoids infused mouthwash products are as effective as chlorhexidine on inhibition of total-culturable bacterial content in dental plaque samples

BackgroundDental plaque is a global health problem affecting people of various age groups. Cannabinoids are gaining enormous research attention due to its beneficial properties for various applications. A preliminary observation on antimicrobial property of cannabinoids against dental plaque bacteria has been reported recently. As a follow-up research, here we report the in vitro evaluation of cannabinoids infused mouthwash products against total culturable (aerobic) bacterial content from dental plaque samples.MethodsWe tested two cannabinoid-infused mouthwash products containing cannabidiol (CBD) and cannabigerol (CBG) respectively (each mouthwash containing < 1% cannabinoid by weight) in vitro against total-culturable bacteria from dental plaque samples collected from 72 adults aged between 18 and 83 years. The participants were grouped on the basis of Dutch periodontal screening index (DPSI) score. To compare the efficacy of our products, we included two most commonly available products over the counter (Product A and Product B) to represent commercially available mouthwash products and the gold standard chlorhexidine digluconate 0.2% as a positive control. The product A represents mouthwash containing essential oils and alcohol, and Product B represents alcohol-free mouthwash that contains fluoride. All the mouthwash products were evaluated directly as such without any dilution through disc diffusion and agar well diffusion approaches and the diameter of zone of inhibition was measured. The limitation in methodology was that, the samples were open-label and the person who performed the manual measurements was unblind to test and control products used.ResultsOn average, the cannabinoids infused mouthwash products showed the similar bactericidal efficacy as that of chlorhexidine 0.2%. Both chlorhexidine 0.2% and cannabinoids infused mouthwash products were effective against all the samples tested. Product A did not show any significant antimicrobial activity in any of the samples tested, except that a very marginal inhibition with a zone of 7-8 mm was observed only in 9 samples. Product B did not show any detectable inhibition zone at all in any of the samples tested. The ranges of zones of inhibition (and their average) were 8–25 mm (18.1 mm) for CBD-mouthwash, 8–25 mm (17.7 mm) for CBG-mouthwash; 12–25 mm (16.8 mm) for chlorhexidine 0.2%; 0–8 mm (0.1 mm) for Product A; and 0 mm for Product B. Although the difference in performance was slightly higher than chlorhexidine in both the cases, the difference was statistically significant for CBD-mouthwash and near significant for CBG-mouthwash. No significant difference was observed between CBD- and CBG-mouthwash. No significant difference in performance was found between DPSI score groups for any of the product tested. To our knowledge this is the first report on such efficient mouthwash product with natural key ingredients including cannabinoids and without any kind of fluoride or alcohol.ConclusionsOur in vitro results demonstrate the potential of cannabinoids in developing efficient and safer mouthwash products and next generation oral care products without fluoride and alcohol.

Risk indicators of dental caries and gingivitis among 10−11-year-old students in Yangon, Myanmar

To obtain basic data on dental caries and gingival status of students in Myanmar, and to identify related risk indicators, including socioeconomic conditions and oral health behaviours and habits. This cross-sectional study enrolled 537 fifth-grade students in Myanmar. Oral health behaviours and dietary patterns of students were assessed using questionnaires. Oral examinations were conducted to identify dental caries and gingivitis, and the oral samples were obtained to determine the bacteria levels in dental plaque. The dental caries prevalence was 68.5%, with a mean number of decayed teeth of 2.07±2.15. The prevalence of gingivitis was 98.9%, and the mean number of inflamed gingival areas in the anterior region was 16.2±5.4. No significant differences were found between the sexes in terms of dental caries and gingivitis. Oral hygiene was significantly poorer, and levels of bacteria in dental plaque were significantly higher in boys than in girls. Multiple linear regression tests were used to analyse the association between risk indicators and dental caries and gingivitis. Tooth brushing frequency, a daily habit of mouth rinsing, dental visit experience, consumption of sugary snacks and oral hygiene status were significantly associated with dental caries. Mother's occupation, tooth brushing frequency, consumption of sweet drinks, oral hygiene status and bacterial levels in dental plaque were significant predictors of gingivitis. Myanmar students had a high prevalence of dental caries and gingivitis. Socioeconomic condition, oral hygiene status and oral health behaviours were all determined to be significant risk indicators.

Dynamics of Dissolution, Killing, and Inhibition of Dental Plaque Biofilm.

The present study aims to establish a standardized model that makes it possible to evaluate the dynamic dissolution of biofilm, killing of biofilm microbes and inhibition of growth of biofilm by disinfecting solutions. Biofilm was grown from dental plaque bacteria on collagen-coated hydroxyapatite (HA) disks for 3 days or 3 weeks under anaerobic conditions. Biofilms were stained with the LIVE/DEAD viability stain and subjected to sterile water, 2% sodium hypochlorite (NaOCl), 6% NaOCl, or 2% chlorhexidine (CHX) for 32 min. Dynamic change in fluorescence on bacterial cells and extracellular polymeric substance (EPS) during the exposure was analyzed using Alexa Fluor 647-labeled dextran conjugate and a live-cell imaging confocal laser scanning microscopy (LC-CLSM). The biofilm structures after treatments were visualized by scanning electron microscopy (SEM). The treated biofilms on HA disks were collected and subjected to colony forming unit (CFU) counting. Another set of sterile HA disks were coated with CHX prior to the monitoring of plaque biofilm growth for 12 h. The LC-CLSM results showed that NaOCl dissolved biofilm effectively, more so at a higher concentration and longer exposure time. Six percent NaOCl was the most effective at dissolving and killing bacteria (e.g., 99% bacterial reduction in 3-day-old biofilm and 95% bacterial reduction in 3-week-old biofilm in 32 min) followed by 2% NaOCl and CHX. Sodium hypochlorite dissolved over 99.9% of the EPS whereas CHX only slightly reduced the EPS biovolume in 32 min. CFU results indicated that the dispersed biofilm bacteria are more resistant than planktonic bacteria to disinfectants. SEM showed the disruption of biofilm after exposures to CHX and NaOCl. The use of 2% CHX and sterile water did not result in biofilm dissolution. However, prior exposure of the HA disks to 2 and 0.2% CHX for 3 min prevented biofilm from growing on the HA disk surfaces for at least 12 h. This new platform has the potential to aid in a better understanding of the antibiofilm properties of oral disinfectants.

Anti-phosphoryl Choline and hs - CRP in Serum of Atherosclerosis Cardiovascular Patient with Chronic Periodontitis

Background: Periodontitis and Atherosclerosis Cardiovascular disease are chronic inflammatory diseases which are highly prevalent. Over the last two decades, the amount of evidence corroborating an association between dental plaque bacteria and coronary diseases that develop as a result of atherosclerosis has increased. The aim of study: was to evaluate the periodontal health status in study groups (Atherosclerotic cardiovascular disease patients with chronic periodontitis (ATH+CP) and patients having chronic periodontitis (CP)), to investigate the serum level of antiphosphorylcholine antibody-IgG(AntiPC IgG) , and the systemic level of inflammatory marker of cardiovascular diseases like high sensitivity C-reactive protein (hs-CRP) in chronic periodontitis with and without atherosclerosis cardiovascular disease as well as to examine the relationships between these mediators and clinical periodontal parameters. Material and Methods: Blood samples were collected from sixty patients (30 CP patients and 30 CP+ATH patients) and from 25 apparently healthy volunteers were enrolled in this study. Periodontal parameters used in this study were plaque index (P.I), gingival index (G.I), bleeding on probing(BOP), probing pocket depth(PPD) and clinical attachment level (CAL) and Serum levels of Anti-PC IgG was estimate by enzymelinkedimmunosorbent assays (ELISA) and hs-CRP was estimate by immunoturbidimetric. Results: The current data revealed a significant elevation (p&lt;0.01) in median level of hs-CRP in CP group and CP+ ATH group in comparison to that in healthy control, moreover, the comparison between two groups of patients showed significant differences between two groups (p&lt;0.05) .Whereas the serum level of antiphosphorylcholine-IgG was not observed significant differences between study groups (p&gt;0.05) except for CP group when compared to control group (p?0.05).Moreover, in regards to the correlation between serum antiphosphorylcholine –IgG and hs-CRP, and clinical periodontal parameters, did not show any correlation with clinical parameters of periodontitis (p&gt;0.05). Conclusion: inflammatory mediator (hs-CRP) may increase inflammatory activity in atherosclerotic lesions and potentially increasing the risk for cardiovascular events in CP+ATH, furthermore, about the effect of Anti-PC IgG in ATH +CP group, further studies are needed to obtain more understanding result.

Different Types of Gel Carriers as Metronidazole Delivery Systems to the Oral Mucosa.

Periodontal diseases are some of the most widespread oral afflictions, and they are labeled as chronic infections caused by the accumulation of bacteria in dental plaque that produces localized inflammation of the periodontium. The use of local drug delivery systems to treat periodontal diseases has received greater attention, because the active substance is targeted directly to the affected area, which minimizes its systemic side effects. Therefore, the purpose of the investigation was to develop and characterize different types of gel formulations—bigel, hydrogel and oleogel—as local delivery systems containing metronidazole (MET), which can be applied to the oral mucosa. The influence of the formulation type on the mechanical, rheological and mucoadhesive properties were examined. Moreover, in vitro release of metronidazole, its ex vivo permeation through buccal porcine mucosa and antimicrobial activity measured by the plate diffusion method were estimated. It was found that the gel formulations obtained were non-Newtonian systems, showing a shear-thinning behavior and thixotropic properties with good textural features such as firmness, compressibility and adhesiveness. Moreover, the preparations designed possessed beneficial mucoadhesive properties. The formulated hydrogels and bigels containing micronized MET were considered as better formulations in terms of drug release and antimicrobial activity compared to commercially available metronidazole ointment. An ex vivo permeation study with the use of porcine buccal mucosa demonstrated that the bigel formulation was characterized by higher initial permeability rate providing a fast therapeutic effect with simultaneous moderate retention in mucosal tissue to decrease the risk of local cytotoxicity.

Phytochemical Characterisation and Antibacterial Activity of Propolis on Cariogenic Microrganisms

Background: Dental caries is also known as tooth decay is as a result of the softening of hard dental tissues from factors of multiple origins, with dental plaque bacteria being one of the most important factors. Due to the resistance of microorganisms to common antibiotics, modern medical sciences had been looking for new approaches in the treatment and prevention of oral diseases. &#x0D; Objective: This study aimed to phytochemically characterise, evaluate the antibacterial activity of propolis on bacteria responsible for dental caries.&#x0D; Methodology: This was an experimental study that took place in the Laboratory of Chemistry and Microbiology (Clinque Universities des Montagne (CUM)) of Bangangté between January to April 2018.&#x0D; Chemical screening of the aqueous and hydroethanolic extracts revealed the presence of secondary metabolites namely alkaloids, flavonoids, tannins, coumarins, saponins and terpenes, those being more abundant in the aqueous extract. The content of flavonoids was high. Macro-dilution was used to determine the minimum inhibitory concentrations (MIC) of propolis and Müller Hinton agar was used for obtaining the minimum bactericidal concentrations (MBC) and determination of inhibition diameters of the bacteria.&#x0D; Results: The flavonoid content in the aqueous extract was estimated at 222.85 mg/ml and 18.77 mg/ml for the hydroalcoholic extracts. S mutans and Lactobacillus spp. were isolated from samples collected from caries affected teeth. The aqueous extract of propolis generally generates greater inhibition diameters than that of the hydroalcoholic extract on both lactobacillus and Streptococcus mutans, The MBC of the aqueous extract on S. mutans and Lactobacillus spp. was 50 mg/ml and the MIC was 25 mg/ml. The hydroalcoholic extract did not have MBC on both S. mutans and Lactobacillus spp. However, the MIC of this extract on both bacteria was 50 mg/ml. These antibacterial properties were not statically significant as that of gentamicin.&#x0D; Conclusion: The evaluation of the antibacterial activity of our various extracts by determination of the MIC and MBC revealed that propolis was endowed with inhibitory properties vis-à-vis the growth of most bacterial strains tested: Streptococcus mutans and Lactobacillus spp. all 2 being gram-positive bacteria.

CBD-supplemented Polishing Powder Enhances Tooth Polishing by Inhibiting Dental Plaque Bacteria.

ABSTRACTObjective:Air polishing is a safe tooth polishing technique used by dental professionals for stain and plaque removal and as a preventive procedure for dental health. We previously reported the antibacterial properties of cannabinoids against dental plaque bacteria. The objective of this study was to analyze the possibilities to improvise the existing air-polishing technique by supplementing cannabinoid powder into the classic polishing powder for effective removal of supragingival and subgingival plaque and for inhibition of plaque-forming bacteria.Materials and Methods:The cannabidiol (CBD) powder was added to the tooth polishing powder (AIR-N-GO, classic) at a 1% (wt/wt) ratio. The study was conducted on 12 patients, of whom six received regular polishing treatment and six received CBD-supplemented polishing treatment. The dental plaque samples were collected before and after each treatment and subjected to in vitro microbiological analysis, and the colony forming units (CFU) were analyzed by using an automated colony counter.Results:Based on in vitro microbiological analysis, the average CFU of interdental space samples collected from post-CBD-supplemented polishing treatment was significantly reduced (linear fold change between 3.9 and 18.4) compared with that of postregular polishing (linear fold change between 1.0 and 2.6) treatment.Conclusions:The CBD-supplemented polishing powder can help in effective removal and killing of dental plaque bacteria during the polishing treatment; it can also be added as an enhancing supplement to the existing polishing powders.

Evaluating the Antimicrobial Efficacy of an Innovative, Novel Herbal Formulation on Dental Caries and Plaque Microorganisms - A Clinical Research.

To develop a novel, innovative herbal formulation that can prevent both dental caries and periodontal diseases simultaneously. This clinical research involved in vitro studies to determine Minimum Inhibitory Concentration (MIC) of combinations of Acacia nilotica, Murraya koenigii Linn Sprengel, Eucalyptus hybrid, and Psidium Guajava on dental caries and plaque bacteria followed by evaluation of phytochemical constituents in these plant extracts. MIC was determined using broth dilution method. Then, an animal experimentation was carried out to determine median lethal dose and adverse drug reactions following single oral administration of polyherbal extract which was followed by human experimentation. A short term double blind randomized double blind study on 34 adult human volunteers was undertaken to assess antiplaque efficacy of a novel polyherbal mouth rinse using 0.2% chlorhexidine as positive control.MIC of the polyherbal combinations on S. mutans, S. sanguis, S. salivarius, L. acidophilus, F. nucleatum and P. gingivalis was found to be 0.25%, 0.05% , 0.05%, 0.1%, 0.25% and 0.25% respectively. Median lethal dose (LD50) for herbal formulation was found to be more than 2000mg/kg body weight. In vivo study found that the polyherbal mouth rinse group had lesser plaque buildup, S mutans and total viable count in comparison with saline group with no significant difference in plaque build-up and total viable count between polyherbal rinse group and 0.2% chlorhexidine. Polyherbal mouth rinse containing Acacia nilotica, Murraya koenigii L.sprengel, Eucalyptus hybrid and Psidium guajava was effective against dental caries and plaque induced dental diseases.

Probiyotiklerin Diş Çürüklerinin Oluşumu Üzerine Etkisi

Dünya Sağlık Örgütü/ Gıda ve İlaç İdaresinin raporuna göre probiyotikler, ‘‘yeterli miktarda tüketildikleri zaman konak sağlığı üzerinde olumlu etkiler görülmesini sağlayan canlı mikroorganizmalar‘‘ olarak ifade edilmektedir. Probiyotikler hastalıkların tedavi edilmesinde ve genel sağlığı desteklemede kullanılmaktadırlar. Probiyotik bakterilerin diş çürüğünü engellemesi ve yavaşlatabilmesi için, diş yüzeylerine yapışabilmesi ve mikrobiyal dental plağı oluşturan bakterilerin arasına katılması gerekmektedir. Bununla birlikte probiyotik bakteriler karyojenik bakterilerle yarışmalı, üremelerini önleyebilmeli ve bu bakterilere zarar verebilmelidir. Ayrıca probiyotik bakteriler karbonhidrat metabolizmasını etkileyerek, asit üretimini azaltabilmelidir. Probiyotikler ağız mikrobiyolojisi ve ağız hastalıkları alanlarında yeni ve ilginç bir araştırma konusudur. Bu konuda yapılacak geniş kapsamlı epidemiyolojik araştırmalar, probiyotiklerin insan sağlığı üzerine daha farklı yararlarını ortaya koyabilecektir.

Fusobacterium Species and Subspecies Differentially Affect the Composition and Architecture of Supra- and Subgingival Biofilms Models.

Fusobacteria are common obligately anaerobic Gram-negative bacteria of the oral cavity that may act as a bridge between early and late colonizing bacteria in dental plaque and have a role in oral and extra-oral infections. Fusobacterium nucleatum has a crucial role in oral biofilm structure and ecology, as revealed in experimental and clinical biofilm models. The aim of this study was to investigate the impact of various Fusobacterium species on in vitro biofilm formation and structure in three different oral biofilm models namely a supragingival, a supragingival “feeding”, and a subgingival biofilm model. The standard six-species supragingival and “feeding” biofilm models employed contained Actinomyces oris, Candida albicans, Streptococcus mutans, Streptococcus oralis, Veillonella dispar, and Fusobacterium sp. The subgingival biofilm model contained 10 species (A. oris, Campylobacter rectus, F. nucleatum ssp. nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Streptococcus anginosus, S. oralis, Tannerella forsythia, Treponema denticola, and V. dispar). Six different Fusobacterium species or subspecies, respectively, were tested namely F. nucleatum ssp. fusiforme, F. nucleatum ssp. nucleatum, F. nucleatum ssp. polymorphum, F. nucleatum ssp. vincentii, F. naviforme, and F. periodonticum). Biofilms were grown anaerobically on hydroxyapatite disks in 24-well culture dishes. After 64 h, biofilms were either harvested and quantified by culture analysis or proceeded to fluorescent in situ hybridization (FISH) and confocal laser scanning microscopy (CLSM). All Fusobacterium species tested established well in the biofilms, with CFUs ranging from 1.4E+04 (F. nucleatum ssp. fusiforme) to 5.6E+06 (F. nucleatum ssp. nucleatum). The presence of specific Fusobacterium sp./ssp. induced a significant decrease in C. albicans levels in the supragingival model and in V. dispar levels in the “feeding” supragingival model. In the subgingival model, the counts of A. oris, S. oralis, P. intermedia, P. gingivalis, and C. rectus significantly decreased in the presence of specific Fusobacterium sp./ssp. Collectively, this study showed variations in the growing capacities of different fusobacteria within biofilms, affecting the growth of surrounding species and potentially the biofilm architecture. Hence, clinical or experimental studies need to differentiate between Fusobacterium sp./ssp., as their biological properties may well vary.

Effect of Oral Spray on Dental Plaque Bacteria and Oral Epithelial Cells

Background: Good oral health is important for systemic body health and quality of life. Spray oral cleansers are increasingly preferred because of their convenience of carrying and the ease of oral hygiene management. In addition, many kinds of oral cleanser products containing various ingredients with antibacterial, washing, and moisturizing effects are being manufactured. However, concerns about the safety and side effects of oral sprays are increasing, and there is very little information regarding the use and care of oral sprays is available to consumers. This study aimed to investigate the effects of oral spray on oral bacteria and tissue to elucidate the factors that need to be considered when using oral sprays. Methods: The effects of oral spray on the growth of dental plaque bacteria was assessed using disk diffusion assays. Cytotoxicity and morphological changes in oral epithelial cells were observed by microscopy. The effects of oral spray on dental plaque growth were also confirmed on specimens from permanent incisors of bovines by Coomassie staining. Results: The pH of spray products, such as Perioe Dental Cooling, Cool Sense, and Dentrix, were 3.65, 3.61, and 6.15, respectively. All tested spray products showed strong toxicity to dental plaque bacteria and oral epithelial cells. Compared with those on the control, dental plaque bacteria deposits on the enamel surface increased following the use of oral spray. Conclusion: Three types of oral spray, namely Perioe Dental Cooling, Cool Sense, and Dentrix, strongly inhibited the growth of dental plaque bacteria and oral epithelial cells. The oral spray ingredient enhanced dental plaque growth on the enamel surface. Users should be informed of precautions when using oral sprays and the need for oral hygiene after its use.

Myricetin Inhibition of Peptidoglycan-Induced COX-2 Expression in H9c2 Cardiomyocytes.

Peptidoglycan (PGN) is a cell wall constituent in dental plaque bacteria that triggers inflammatory responses. PGN binds Toll-like receptors, leading to increases in prostaglandin E2 and interleukin-1β, which play crucial roles in the inflammatory response and tissue destruction. Dental surgery can give plaque bacteria access to blood circulation, thereby creating a risk of septic inflammation of the endocardium. Plant-derived flavonoids have been reported to reduce inflammatory cytokine secretion by host cells. In the present study, we investigated the effects of flavonoid myricetin on expression of cyclooxygenase 2 (COX-2) in the H9c2 cells treated with PGN from Streptococcus sanguinis, a bacterial constituent of dental plaque associated with infective endocarditis. Myricetin exposure resulted in dose-dependent suppression of PGN-induced COX-2 expression, diminished phosphorylation of p38, extracellular signal regulated kinase 1/2, and c-Jun N-terminal kinase, and reduced IκB-α degradation, consistent with decreased COX-2 activity. In conclusion, the aforementioned results suggest that myricetin is useful for moderating the inflammatory response in infective endocarditis.

Dental plaque bacteria

Dental plaque bacteria

The effect of smoking on caries-related microorganisms.

INTRODUCTIONEpidemiological studies have shown a close relationship between smoking and dental caries. Bacteria are one of the essential factors of caries formation. The imbalance of cariogenic bacteria and commensal bacteria in dental plaque results in higher production of acid that can corrode dental hard tissue. The aim of our review is to summarize the effect of smoking on caries-related bacteria.METHODSEnglish articles available in Pubmed and ScienceDirect databases and published before December 2018 were searched. A variety of evidence was collected including not only the influence of cigarette products on bacteria strains in vitro but also their effect on bacterial composition in saliva and dental plaque in vivo. We particularly emphasize the mechanisms by which nicotine acts on oral bacteria.RESULTSThe components of cigarettes promote the growth of cariogenic microorganisms. The mechanisms of how nicotine enhances Streptococcus mutans, Lactobacilli, Streptococcus gordonii, Actinomyces and Candida albicans are described separately in detail. The commensal bacteria, Streptococcus sanguinis, show less competitive capability in the presence of nicotine. Smoking influences saliva by lowering the buffer capability, altering its chemical agent and bacterial components, and therefore promotes the formation of a caries-susceptible environment.CONCLUSIONSCigarette smoking and nicotine exposure promote the cariogenic activity of oral microorganisms and the formation of a caries-susceptible environment. This suggests that smokers should quit smoking, amongst other health reasons, also for their oral health.

Fluoride toothpastes of different concentrations for preventing dental caries.

Fluoride toothpastes of different concentrations for preventing dental caries.

Micro-Raman Spectroscopy Reveals the Presence of Octacalcium Phosphate and Whitlockite in Association with Bacteria-Free Zones Within the Mineralized Dental Biofilm.

Through a correlative analytical approach encompassing backscattered electron scanning electron microscopy (BSE-SEM), energy dispersive X-ray spectroscopy (EDX), and micro-Raman spectroscopy, the composition of the mineralized biofilm around a dental implant, retrieved due to peri-implantitis, was investigated. The mineralized biofilm contains two morphologically distinct regions: (i) bacteria-containing zones (Bact+), characterized by aggregations of unmineralized and mineralized bacteria, and intermicrobial mineralization, and (ii) bacteria-free zones (Bact-), comprised mainly of randomly oriented mineral platelets. Intramicrobial mineralization, within Bact+, appears as smooth, solid mineral deposits resembling the morphologies of dental plaque bacteria. Bact- is associated with micrometer-sized Mg-rich mineral nodules. The Ca/P ratio of Bact+ is higher than Bact-. The inorganic phase of Bact+ is carbonated apatite (CHAp), while that of Bact- is predominantly octacalcium phosphate (OCP) and whitlockite (WL) inclusions. Compared with native bone, the inorganic phase of Bact+ (i.e., CHAp) exhibits higher mineral crystallinity, lower carbonate content, and lower Ca/P, C/Ca, Mg/Ca, and Mg/P ratios. The various CaPs found within the mineralized dental biofilm (CHAp, OCP, and WL) are related to the local presence/absence of bacteria. In combination with BSE-SEM and EDX, micro-Raman spectroscopy is a valuable analytical tool for nondestructive investigation of mineralized dental biofilm composition and development.

Elusive function of dental plaque polysaccharide produced from Kocuria rosae and it’s molecular signature

Background Exopolysaccharides have been generally recognized as safe compounds, meaning that they do not represent a health risk when used. Owing to these properties, they have many applications in industrial areas and in healthcare. Our aim is to identify an extracellular polysaccharide (EPS)-producing strain from dental plaque bacteria and the verification of its polysaccharide’s antitumor effect. Materials and methods Isolation of 22 dental plaque bacterial isolates from plaque samples of nine patients was carried out using pour plate method. The selection of the strain for molecular identification was done according to EPS production, whereas isolate no. 4 was identified by 16S rRNA sequencing analysis. Structure characterization of the EPS was described using UV and SEM images. The cytotoxic experiment was performed to investigate the inhibitory effect of different concentrations of EPS on the growth of cell line MCF7 human White breast adenocarcinoma. Results and conclusion Oral plaque bacteria vary greatly in their occurrence, depending on age, presence of systemic diseases, and personal oral hygiene. The amount of EPS produced from oral plaque bacteria also varies, though in general Gram-negative bacteria yielded larger amounts of EPS. Results revealed that isolate no. 4 is the most producer of EPS, identified as Kocuria rosea strain Y57, having 96% similarity with Kocuria spp. The biosynthesis of EPS from K. rosea using Luria–Bertani broth medium at 37°C for 24 h gave an EPS yield of 213 μg/ml. EPS from K. rosea is a powder with white color and is water soluble. Our results of in-vitro EPS assay against MCF7 human White breast adenocarcinoma released activity with LC50 213 μg/ml.

Gingival Crevicular Fluid: An Overview.

Gingival crevicular fluid is an inflammatory exudate derived from the periodontal tissues. It is composed of serum and locally generated materials such as tissue breakdown products, inflammatory mediators, and antibodies directed against dental plaque bacteria. It plays a special part in maintaining the structure of junctional epithelium and the antimicrobial defense of periodontium. Some of the suspected periodontal pathogens such as Porphyromonas gingivalis and Treponema denticola produce broad-spectrum neutral proteinases as part of their virulence arsenal. These proteinases may be detected in plaque and gingival crevicular fluid samples of patients with periodontitis. The potential diagnostic importance of gingival fluid was recognized more than six decades ago. The fluid component of gingival crevicular fluid is derived primarily from microvascular (postcapillary venule) leakage. There are number of distinct advantages and challenges of using gingival crevicular fluid as a diagnostic test for periodontal disease.