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OBJECTIVES It has been suggested that smoking affects the oral microbiome, but its effects on sites other than the subgingival microbiome remain unclear. This study investigated the composition of the salivary and tongue bacterial communities of smokers and nonsmokers in periodontally healthy adults. METHODS The study population included 50 healthy adults. The bacterial composition of resting saliva and the tongue coating was identified through barcoded pyrosequencing analysis of the 16S rRNA gene. The Brinkman index (BI) was used to calculate lifetime exposure to smoking. The richness and diversity of the microbiome were evaluated using the t-test. Differences in the proportions of bacterial genera between smokers and nonsmokers were evaluated using the Mann-Whitney U test. The quantitative relationship between the proportions of genera and the BI was evaluated using Pearson's correlation analysis. RESULTS The richness and diversity of the oral microbiome differed significantly between saliva and the tongue but not between smokers and nonsmokers. The saliva samples from smokers were enriched with the genera Treponema and Selenomonas. The tongue samples from smokers were enriched with the genera Dialister and Atopobium. The genus Cardiobacterium in saliva, and the genus Granulicatella on the tongue, were negatively correlated with BI values. On the other hand, the genera Treponema, Oribacterium, Dialister, Filifactor, Veillonella, and Selenomonas in saliva and Dialister, Bifidobacterium, Megasphaera, Mitsuokella, and Cryptobacterium on the tongue were positively correlated with BI values. CONCLUSIONS The saliva and tongue microbial profiles of smokers and nonsmokers differed in periodontally healthy adults. The genera associated with periodontitis and oral malodor accounted for high proportions in saliva and on the tongue of smokers without periodontitis and were positively correlated with lifetime exposure to smoking. The tongue might be a reservoir of pathogens associated with oral disease in smokers.

A randomized, double-blind, placebo-controlled crossover comparative study was conducted in a healthy older population to assess the usefulness ofThe study population included 33 healthy older individuals who were randomly divided into two groups (A and B). Group A consumed WB21 tablets during the first two months and placebo tablets during the following two months. Group B consumed placebo tablets during the first two months and WB21 tablets during the following two months. Before and after ingestion, oral examination, mouth odor test, and saliva collection were performed a total of four times. In addition, health conditions were obtained from a questionnaire survey at the study's midpoint.Two people in group A and one person in group B dropped out of the study. Thus, 15 people in group A and 15 people in group B were included in the analysis. Over two months of WB21 ingestion, salivary secretory IgA increased significantly (Continuous ingestion of WB21-containing tablets may promote self-care of the teeth and mouths of healthy older adults.R000028335 (UMIN-CTR).

Objective We sought new markers to predict oral malodor. Study Design Seventy-five adults complaining of oral malodor were classified into 3 groups clinically: no oral malodor, physiologic oral malodor, and periodontitis-derived oral malodor. In addition to conventional clinical parameters, 7 salivary components, occlusal force, and lip-closing force were compared among the groups. Results Concerning the salivary components, cariogenic bacteria, occult blood, leukocytes, and ammonia differed significantly among the groups. Multiple logistic regression analyses indicated that tongue-coating scores and ammonia levels were significantly associated with genuine oral malodor, including physiologic oral malodor and periodontitis-derived oral malodor, and the tongue-coating score, plaque index, and occult blood level were significantly associated with periodontitis-derived oral malodor. Occlusal force and lip-closing force did not differ among the groups. However, there was a statistically significant interaction between occlusal force and lip-closing force in oral malodor in women (P = .019). Conclusions Novel salivary markers, ammonia levels, and occult blood levels may predict genuine oral malodor and periodontitis-derived oral malodor, respectively. An interaction effect between occlusal force and lip-closing force on oral malodor was identified in women.

Objective For dental students, textbooks and lectures provide basic knowledge, and simulated and actual clinical training provide learning in technical and communication skills. At our college, conservative dentistry is taught in the third and fourth years of a 6‐year undergraduate degree. Clinical training is undertaken subsequently in the fifth year and includes cavity preparation and composite resin filling tasks. However, despite the clinical importance of a full understanding surrounding these procedures, sixth‐year students occasionally provide incorrect answers regarding these procedures in assessments. Although they demonstrated a basic understanding of the procedures, they may have forgotten the acquired knowledge during their clinical training. Therefore, we developed an error‐detection examination to evaluate and improve fifth‐year students' knowledge. Methods Written detailed treatment procedures for standardized, typical, cases were presented to students. Some critical steps were intentionally written incorrectly, and students had to identify and correct these. After correcting the steps, students gave a presentation to their peers on their corrections. This was followed by a summary of the correct answers and a short lecture by the teacher. Students then completed a questionnaire investigating their experience of the examination. Results Students misunderstood some key treatment steps, such as pretreatment of composite resin filling, amalgam removal, and ceramic inlay fitting. The questionnaire revealed that this method of testing applied knowledge was new to students and helped them to identify knowledge gaps. The test also increased their motivation to study conservative dentistry. Students were open to taking similar tests in different areas. Conclusion Although conservative dentistry is a basic field of dental treatment, mistakes in treatment can lead to early treatment failure or reduce the lifetime of a restored tooth. Therefore, students need to have a deep understanding of procedures. Error‐detection examinations may help students identify knowledge gaps and provide useful feedback to teachers to identify areas that they should stress in earlier years.

Objective To investigate associated risk factors for oral candidiasis in elderly patients hospitalized in a community-based acute-care hospital with no dental units. Methods Two hundred and twenty-eight elderly patients (male: 105, female: 123), who were hospitalized with several systemic diseases in a community-based acute-care hospital from May 2014 to October 2016, were retrospectively analysed by multiple logistic regression. Results Multiple logistic regression analysis shows that bacterial pneumonia has a statistically strong relationship with oral candidiasis (p = 0.000, OR: 5.173, 95% CI: 2.368-11.298). The order followed is poor oral hygiene (p = 0.001, OR: 6.095, 95% CI: 2.003-18.545) and severe dry mouth (p = 0.043, OR: 2.507, 95% CI: 1.031-6.098). Other correlated factors including diabetes mellitus, denture wearer, dysphagia, malnutrition, requiring care and use of inhalation steroids, were not statistically significant in this study. Conclusions Bacterial pneumonia correlates with oral candidiasis.

Volatile sulfur compounds (VSCs) such as hydrogen sulfide (H2 S) and methyl mercaptan (CH3 SH) are the main components of oral malodor, and are produced as the end products of the proteolytic processes of oral microorganisms. The main pathway of proteolysis is the metabolism of sulfur-containing amino acids by gram-negative anaerobic bacteria. Gram-positive bacteria may promote VSC production by gram-negative anaerobes by cleaving sugar chains from glycoproteins and thus providing proteins. A large variety of bacteria within the oral microbiota are thought to be involved in the complex phenomenon of halitosis. Oral microbiota associated with a lack of oral malodor, oral microbiota associated with severe and H2 S-dominant oral malodor, and oral microbiota associated with severe and CH3 SH-dominant oral malodor have been distinguished through molecular approaches using the 16S rRNA gene. Pathological halitosis may primarily be addressed through treatment of causative diseases. In all cases, plaque control is the basis of oral malodor control, and dentifrices, mouthwashes, and functional foods play a supplementary role in addition to brushing. Recently, the use of natural ingredients in products tends to be favored due to the increase in antibiotic-resistant strains and the side effects of some chemical ingredients. In addition, probiotics and vaccines are expected to offer new strategies for improving the oral conditions through mechanisms other than antibacterial agents.

Objective Although a relationship between Helicobacter pylori and oral malodor has been suggested, it remains to be confirmed. One reason for this is that many studies assess oral malodor subjectively. Another reason for the uncertainty is that the reduction in oral malodor may be due to the effect of antibiotics on the oral microbiota. In this study, changes in oral malodor along with the eradication treatment of H. pylori were investigated by organoleptic test and gas chromatography. In addition, the salivary bacterial composition and clinical parameters were analyzed. Results The organoleptic test score, hydrogen sulfide and dimethyl sulfide concentrations, and all clinical parameters except for tongue-coating score were significantly decreased at 1 week compared with baseline. Although antibiotic treatment also altered the overall composition of the salivary bacterial population, it had recovered at 7 weeks. On the date that H. pylori was determined to have been eradicated from all of the subjects (7 weeks after treatment), only the organoleptic test score was significantly lower compared with baseline. The hydrogen sulfide and dimethyl sulfide concentrations were non-significantly lower than those at baseline.

Professional oral health care (POHC) is known to prevent aspiration pneumonia in patients with dysphagia and/or those at the perioperative stage of surgery. However, the effect of POHC on patients suffering from aspiration pneumonia remains unknown. Here, we report a case where continual POHC intervention improved severe aspiration pneumonia. A 74-year-old male patient with a brain infarction suffered from severe aspiration pneumonia (PSI: IV, A-DROP: 3) complicated by vascular dementia and severe dysphagia. Because an antimicrobial approach following the treatment guidelines for pneumonia was not effective, we started a POHC intervention to improve his poor oral condition at the request of the attending doctor and the patient’s family. The severe pneumonia markedly improved after continual POHC by the dental team. This case suggests that continual POHC intervention by a dental hygienist may improve severe aspiration pneumonia.

Summary The role of macrophage infiltrates in oral mucosal acute graft-versus-host disease (AGVHD) remains unclear, although clinical studies suggest that macrophage infiltration correlates directly with the severity of AGVHD. In this study, we investigated the role of M1 macrophage infiltration in the oral mucosa of rats with AGVHD. Lewis rat spleen cells were injected into (Lewis × Brown Norway) F1 rats to induce systemic GVHD. Tongue samples were evaluated using histology, immunohistochemistry, dual immunofluorescence, real-time reverse transcription–polymerase chain reaction, Transwell migration assays and Stamper–Woodruff binding assays. At the onset of oral mucosal AGVHD, dual immunofluorescence and migration assays revealed that M1 macrophages had accumulated in the basement membrane (BM) region via the laminin/CD29 β1 integrin pathway. Macrophage-secreted matrix metalloproteinase-2 was related to BM degradation. The adhesion of macrophages to the oral epithelium could be inhibited by pretreating macrophages with a CC chemokine receptor 2 (CCR2) antibody and/or pretreating lesion sections with monocyte chemoattractant protein-1 (MCP-1) antibody. Our data show that the migration and adhesion of M1 macrophages are associated with oral mucosal AGVHD, which is mediated in part by both laminin/CD29 β 1 intern and MCP-1/CCR2 pathways. Therefore, our study provides additional support for the contribution of macrophage infiltrate to the development of oral mucosal AGVHD.

Objectives Volume-regulated anion channels (VRACs), expressed in various cells, play an important role in cell volume regulation. Despite being physiologically defined almost half a century ago, only the molecular candidates of VRAC, TMEM16A, LRRC8A, and bestrophin-1 (BEST1), are known. Here, we aimed to explore the functional significance of VRAC in, HST-1, an oral squamous cell carcinoma (OSCC) cell line. Methods Cell proliferation assays, RT-PCR, Western blot, and flow cytometry were used to estimate changes in gene expression and cell proliferation. Ion channel activity was recorded using the patch-clamp technique. Specific genes were knocked-down by siRNA assays. Results VRAC, identified as a hypotonicity-induced current, was highly functional and associated with the proliferation of HST-1 cells but not of HaCaT (a normal keratinocyte) cells. The pharmacological profile of VRAC in HST-1 was similar to that reported previously. DCPIB, a specific VRAC inhibitor, completely inhibited VRAC and proliferation of HST-1 cells, eventually leading to apoptosis. VRAC in HST-1 was attenuated by the knockdown of TMEM16A and LRRC8A, while knockdown of BEST1 affected cell proliferation. In situ proximity ligation assay showed that TMEM16A and LRRC8A co-localized under isotonic conditions (300 mOsM) but were separated under hypotonic conditions (250 mOsM) on the plasma membrane. Conclusions We have found that VRAC acts to regulate the proliferation of human metastatic OSCC cells and the composition of VRAC may involve in the interactions between TMEM16A and LRRC8A in HST-1 cells.

There is an increasing population of elderly patients suffering from Alzheimer’s disease (AD), the most common form of dementia. In dentistry, a critical problem associated with these patients is the use of a new denture, as AD patients often refuse dental management and are disturbed by minor changes in their oral environment. Some AD patients have further complications associated with oral dyskinesia, a movement disorder that can make dental management difficult, including the stability of a complete denture. In this case, we successfully fitted a complete maxillary denture using modified bilateral balanced occlusion after multiple tooth extractions under intravenous sedation in a 66-year-old woman with severe AD complicated by oral dyskinesia. Following treatment, her appetite and food intake greatly improved. Providing a well-fitting complete denture applied by modified bilateral balanced occlusion, which removes lateral interference using zero-degree artificial teeth for movement disorder of the jaw in patients with severe AD complicated by oral dyskinesia, helps improve oral function.

Background Interactions of resident bacteria and/or their producing lipopolysaccharide (LPS) with sulcular epithelial keratinocytes may be regulated by autophagy in the gingival sulcus. In this study, we investigated an induction of bacterial autophagy in exfoliative sulcular keratinocytes of the gingival sulcus and cultured keratinocytes treated with Porphyromonas gingivalis-originated LPS (PgLPS). Results Exfoliative sulcular keratinocytes showed an induction of autophagy, in addition to increased expression of LPS-mediated factors including lipopolysaccharide-binding protein and toll-like receptors (TLRs), leading to co-localization of bacteria with autophagosomes. In contrast, exfoliative keratinocytes from the free gingiva did not show similar autophagy. Autophagy activity in human cultured keratinocyte cells (HaCaT) was induced by PgLPS, which was dependent partially on the AMP-activated protein kinase (AMPK) pathway via increased intracellular reactive oxygen species (ROS) and was in association with an activation of TLR4 signaling. After incubation of cultured keratinocytes with E.coli BioParticles following PgLPS stimulation, co-localization of bioparticles with autophagosomes was enhanced. Conversely, blockage of autophagy with 3-methyladenin and LPS-binding with polymyxin B led to significant reduction of co-localization of particles with autophagosomes. Conclusion These findings indicate that PgLPS-induced autophagy is at least partially responsible for interaction between bacteria and sulcular keratinocytes in the gingival sulcus.

Both aspiration pneumonia and oral candidiasis are caused by opportunistic infection of intraoral commensals and have many similar risk factors linked to oral health in older adults. Candida albicans forms biofilms with respiratory bacteria such as Klebsiella pneumoniae and Pseudomonas aeruginosa. The aim of our study was to determine the relationship between bacterial pneumonia, including aspiration pneumonia, and oral candidiasis in older patients who were hospitalized with several systemic diseases in a community-based acute care hospital without a dental unit. We retrospectively analyzed 228 older patients (male: 105, female: 123) using multiple logistic regression. The mean age of the patients was 81.3 (SD: 11.1) years. Forty-four patients were oral candidiasis positive, and 78 patients suffered from bacterial pneumonia, including aspiration pneumonia. Results showed that bacterial pneumonia had the strongest statistical relationship with oral candidiasis (p=0.000, OR: 5.173, 95 % CI: 2.368–11.298). This was followed by poor oral hygiene (p=0.001, OR: 6.095, 95 % CI: 2.003–18.545) and severe dry mouth (p=0.043, OR: 2.507, 95 % CI: 1.031–6.098). Other conventional risk factors for oral candidiasis, such as diabetes mellitus, denture wearer, dysphagia, malnutrition, requiring care, use of inhalation steroids, were not statistically significant in this study. Fifteen species of bacteria, including Klebsiella pneumoniae and Pseudomonas aeruginosa, were detected by pharyngeal sputum culture in 24 of 31 patients who were diagnosed with both oral candidiasis and bacterial pneumonia. In conclusion, bacterial pneumonia is a possible new risk factor for oral candidiasis in older adults.

To evaluate the combined use of Lactobacillus salivarius WB21 and (-)-epigallocatechin gallate (EGCg) for oral health maintenance.The effects of L. salivarius WB21 on growth of Streptococcus mutans, the insoluble glucan produced by S. mutans, and on growth of Porphyromonas gingivalis were evaluated in vitro. In addition, the susceptibility of five oral pathogenic bacteria and L. salivarius WB21 to EGCg, the inhibiting effect of EGCg on methyl mercaptan, and the effects of L. salivarius WB21 and EGCg in combination on growth of P. gingivalis were examined.Lactobacillus salivarius WB21 showed concentration-dependent inhibition of the growth of S. mutans. Addition of L. salivarius WB21 inhibited production of the insoluble glucan by S. mutans (p0.001). A filtrate of L. salivarius WB21 culture solution inhibited growth of P. gingivalis (p0.001 vs. control), and this effect was enhanced when it was used in combination with EGCg (p0.001 vs. the addition of L. salivarius WB21). In addition, EGCg directly inhibited methyl mercaptan in a concentration-dependent manner (p0.001). Concerning bacterial susceptibility to EGCg, growth of P. gingivalis, Prevotella intermedia, and Fusobacterium nucleatum was inhibited at 2.5 mg/mL of EGCg, while that of L. salivarius WB21 was inhibited at 25 mg/mL EGCg.Our results imply that L. salivarius WB21 may be useful for controlling dental caries, periodontitis, and oral malodor. In addition, the effects of L. salivarius WB21 on periodontitis and oral malodor may be synergistically enhanced by use in combination with EGCg.

Objectives The aim of this study was to reveal the mechanisms by which zinc ions inhibit oral malodor. Material and Methods The direct binding of zinc ions to gaseous hydrogen sulfide (H2S) was assessed in comparison with other metal ions. Nine metal chlorides and six metal acetates were examined. To understand the strength of H2S volatilization inhibition, the minimum concentration needed to inhibit H2S volatilization was determined using serial dilution methods. Subsequently, the inhibitory activities of zinc ions on the growth of six oral bacterial strains related to volatile sulfur compound (VSC) production and three strains not related to VSC production were evaluated. Results Aqueous solutions of ZnCl2, CdCl2, CuCl2, (CH3COO)2Zn, (CH3COO)2Cd, (CH3COO)2Cu, and CH3COOAg inhibited H2S volatilization almost entirely. The strengths of H2S volatilization inhibition were in the order Ag+ > Cd2+ > Cu2+ > Zn2+. The effect of zinc ions on the growth of oral bacteria was strain-dependent. Fusobacterium nucleatum ATCC 25586 was the most sensitive, as it was suppressed by medium containing 0.001% zinc ions. Conclusions Zinc ions have an inhibitory effect on oral malodor involving the two mechanisms of direct binding with gaseous H2S and suppressing the growth of VSC-producing oral bacteria.

Toothbrushes after use are contaminated by many microorganisms including bacteria, fungi and viruses. We are thinking of making an anti-bacterial toothbrush by including ceramics in the bristle. But if the ceramic-containing bristles are too hard for the tooth and gingiva, it cannot be used as a toothbrush. So, before examining the antibacterial properties, we evaluated the feeling by asking students of dental hygiene. In our preliminary experiment, we determined the most appropriate width and length of ceramic-containing bristles. The students used this toothbrush and answered the questions. Almost all the students were satisfied with the new toothbrush with ceramic-containing bristles. Moreover, the new toothbrush was found to be comparable with the world-wide sold toothbrush. We obtained data that the ceramic-containing bristles were acceptable. Further study to investigate the anti-bacterial properties and effective cleanliness are in progress.

Methods: Approximately 70% of the patients were female and most were in their 40s. We analyzed the possible causes of halitosis. Results: More than half of the patients exhibited a thick tongue coating. Low salivary flow was present in 23.6% of males and in 39.4% of females. Pocket depth ≥6 mm was found in 44.2% of males and in 16.7% of females. We also analyzed treatment provided after breath odor measurement. Most of the patients with physiological halitosis and pseudohalitosis did not receive further treatment, but some were treated at the COD with scaling and professional tooth cleaning. Many of the patients with genuine halitosis received dental treatment at the COD. We referred patients from other clinics and from distant locations to their local doctors for treatment. Conclusion: Halitosis had various causes, and the role of dental hygienists, including scaling, root planing, and tooth brushing instruction, are important in decreasing breath odor. Dental hygienists play an important role in communication with halitosis patients.

Objective: This study presents an effective method of classifying oral malodor from oral microbiota in saliva by using a support vector machine (SVM), an artificial neural network (ANN), and a decision tree. This approach uses concentrations of methyl mercaptan in mouth air as an indicator of oral malodor, and peak areas of terminal restriction fragment (T-RF) length polymorphisms (T-RFLPs) of the 16S rRNA gene as data for supervised machine-learning methods, without identifying specific species producing oral malodorous compounds. Methods: 16S rRNA genes were amplified from saliva samples from 309 subjects, and T-RFLP analysis was carried out with the DNA fragments. T-RFLP analysis provides information on microbiota consisting of fragment lengths and peak areas corresponding to bacterial strains. The peak area is equivalent to the frequency of a specific fragment when one molecule is selected from terminal fragments. Another frequency is obtained by dividing the number of species-containing samples by the total number of samples. An SVM, an ANN, and a decision tree were trained based on these two frequencies in 308 samples and classified the presence or absence of methyl mercaptan in mouth air from the remaining subject. Results: The proportion that trained SVM expressed as entropy achieved the highest classification accuracy, with a sensitivity of 51.1% and specificity of 95.0%. The ANN and decision tree provided lower classification accuracies, and only classification by the ANN was improved by weighting with entropy from the frequency of appearance in samples, which increased the accuracy to 81.9% with a sensitivity of 60.2% and a specificity of 90.5%. The decision tree showed low classification accuracy under all conditions. Conclusions: Using T-RF proportions and frequencies, models to classify the presence of methyl mercaptan, a volatile sulfur-containing compound that causes oral malodor, were developed. SVM classifiers successfully classified the presence of methyl mercaptan with high specificity, and this classification is expected to be useful for screening saliva for oral malodor before visits to specialist clinics. Classification by a SVM and an ANN does not require the identification of the oral microbiota species responsible for the malodor, and the ANN also does not require the proportions of T-RFs.

Sphingosine-1-phosphate (S1P) is a well-known signaling sphingolipid and bioactive lipid mediator. Recently, it was reported that S1P inhibits osteoclast differentiation and bone resorption. On the other hand, S1P effects on osteoblasts and bone formation are little known. In this study, we investigated the effects of S1P on osteoblasts, using two osteoblast-like cell lines, SaOS-2 and MC3T3-E1. S1P activated phosphatidylinositol 3-kinase (PI3K)/Akt signaling, leading to the inhibition of glycogen synthase kinase-3β and the nuclear translocation of β-catenin, followed by the increase of the transcriptional activity by β-catenin/T-cell factor complex formation in both SaOS-2 cells and MC3T3-E1 cells. The inhibitors of PI3K and Akt suppressed S1P-induced nuclear localization of β-catenin. We further investigated the effects of PI3K/Akt signaling on the Wnt/β-catenin signaling pathway, since β-catenin takes a central role in this signaling pathway. Both inhibitors for PI3K and Akt suppressed the nuclear localization of β-catenin and T-cell factor transcriptional activity induced by Wnt-3a. S1P increased the amount of osteoprotegerin at both mRNA and protein levels, and increased the activity of alkaline phosphatase, leading to the mineralization. These findings suggest that S1P activates the PI3K/Akt signaling pathway leading to the promotion of nuclear translocation of β-catenin in osteoblast-like cells, resulting in the upregulation of osteoptotegerin and osteoblast differentiation markers including alkaline phosphatase, probably relating to the inhibition of osteoclast formation and the mineralization, respectively.

The red complex, which includesPorphyromonas gingivalis,Treponema denticola, andTannerella forsythia(formerlyBacteroides forsythus), are recognized as the most important pathogens in adult periodontal disease. These bacteria are usually found together in periodontal pockets, suggesting that they may cause destruction of the periodontal tissue in a cooperative manner. This article discusses the interspecies pathogenic interactions within the red complex.

Volatile sulfur compounds (VSCs) produced by oral anaerobes are the major compounds responsible for oral malodor.Enterococcus faeciumWB2000 is recognized as an antiplaque probiotic bacterium. In this study, the effect ofE. faeciumWB2000 on VSC production byPorphyromonas gingivaliswas evaluated, and the mechanism of inhibition of oral malodor was investigated.P. gingivalisATCC 33277 was cultured in the presence of four lactic acid bacteria, includingE. faeciumWB2000. Subsequently,P. gingivalisATCC 33277, W50, W83, and two clinical isolates were cultured in the presence or absence ofE. faeciumWB2000, and the emission of VSCs from spent culture medium was measured by gas chromatography. The number ofP. gingivalisATCC 33277 in mixed culture withE. faeciumWB2000 decreased at 6 h, and the rate of decrease was higher than that in mixed cultures with the other lactic acid bacteria. The numbers of fiveP. gingivalisstrains decreased at similar rates in mixed culture withE. faeciumWB2000. The concentration of methyl mercaptan was lower in spent culture medium fromP. gingivalisandE. faeciumWB2000 cultures compared with that fromP. gingivalisalone. Therefore,E. faeciumWB2000 may reduce oral malodor by inhibiting the growth ofP. gingivalisand neutralizing methyl mercaptan.

Bisphosphonates and irradiation are useful medical treatments, but can often cause oral complications such as medication-related oral necrosis of the jaw (MRONJ) and osteoradionecrosis (ORN) during oral surgery, including tooth extraction. Therefore, we should take all risks into consideration carefully before choosing dental treatment for patients with a medical history of such therapies. A 55-year-old woman who underwent cord blood transplantation to treat extranodal natural killer T (NK/T) cell lymphoma (nasal type IVB) had a medical history of bisphosphonate and irradiation treatments. We treated her residual tooth root by applying orthodontic extrusion to avoid extraction and successfully restored the tooth. Application of an orthodontic tooth extrusion technique for conservative treatment of a residual tooth is a useful means of avoiding MRONJ or ORN in patients who have a medical history of bisphosphonate and irradiation treatments.

Introduction This study investigated the relationships among salivary stress biomarkers, cigarette smoking, and mood states. Material and Methods The study population comprised 49 healthy sixth-year dental students at Fukuoka Dental College (39 men, 10 women; age, 23–31 years). Lifetime exposure to smoking was calculated using the Brinkman index (BI). Resting saliva samples were collected, and concentrations of cortisol, secretory immunoglobulin A (SIgA), interleukin (IL)-1β, interleukin-6, and tumor necrosis factor (TNF)-α were determined. Mood states (tension-anxiety, depression-dejection, anger-hostility, fatigue, confusion, and vigor) over the previous week were assessed using the Profile of Mood States - Brief Japanese Version. Results Salivary IL-1β levels were significantly higher in smokers than non-smokers (P = 0.044), regardless of the BI or mood state. A significant positive correlation was evident between the TNF-α level and the BI (P = 0.036), and the SIgA level was positively correlated with the BI (P = 0.067) but did not reach statistical significance. In terms of mood states, higher fatigue scores and lower vigor scores were observed in smokers. The TNF-α level and vigor score were negatively correlated (r = –0.229, P = 0.135), but the correlation did not reach statistical significance. However, the SIgA level and fatigue score were significantly positively correlated (r = 0.410, P = 0.005). Conclusions The TNF-α and SIgA levels were both positively correlated with the BI. Furthermore, the TNF-α level was negatively correlated with the vigor score, whereas the SIgA level was positively correlated with the fatigue score. Thus, salivary levels of TNF-α and SIgA may be used as biomarkers of mood states in healthy young smokers.

Here, we report a case of oral malodor that was diagnosed by bacterial examination. The patient (a 32-year-old female) visited our breath clinic because a family member advised her to do so. Strong oral malodor was detected by several tests including an organoleptic test, a portable sulfide monitor, and gas chromatography. She noticed her oral malodor, but her motivation toward treatment was low. Even after explaining the cause of halitosis and the importance of oral hygiene, her motivation did not improve. So we applied a bacterial examination, and explained the results in detail. She understood how oral bacteria had caused the oral malodor, and she tried to do tooth brushing better. After a basic periodontal treatment, her oral condition improved and the number of periodontopathic bacteria reduced. She continued with careful tooth brushing even after the periodontal treatment, and her breath odor remarkably decreased. This case report indicates the usefulness of bacterial examination for motivating patients to improve their oral hygiene.

Many people worry about their breath odor, and the importance of halitosis treatment is increasing. Consequently, it is necessary for dental hygienists to obtain a basic knowledge of halitosis. To achieve this, we must improve the motivation of dental hygienist students to acquire such knowledge. To this end, we conducted a questionnaire survey to assess the awareness and knowledge of the problem among dental hygienist students and compared the results of the survey for students in the first and third grades. The percentage of students who perceived the oral malodor of patients was higher in the third grade group. The third graders also placed a greater importance on the participation of dental hygienists in halitosis treatment. Most students in both grades believed that demand for halitosis treatment would increase, although there were students in the first grade that did not hold this view. A similar percentage of students in the two grades were willing to study halitosis, although some first grade students were not at all interested. Many more students in the third grade wanted to take part in halitosis treatment. Student knowledge of halitosis was approximately the same in both grades, but, surprisingly, the third graders gave some incorrect answers in this area. From the results of this study, the third grade students appeared to have higher motivation to study halitosis treatment than the first graders. However, the upper grade students seemed to lack some knowledge, which may be due to the extended time since they had studied the topic at school. It is necessary for us to improve student motivation for studying halitosis and for maintaining their knowledge in order to better perform the treatment of halitosis after the students become dental hygienists.

Oral bacteria are considered to be associated with several systemic diseases. Recently, their association with inflammatory bowel disease (Crohn's disease and ulcerative colitis) and colorectal carcinoma has attracted much attention. In this mini-review, the association of oral bacteria with these diseases is briefly summarized. Fusobacterium nucleatum is known as a periodontopathic bacterium, and it is also associated with inflammatory bowel disease and colorectal carcinoma. Campylobacter concisus, which is found at the site of periodontitis, is associated with inflammatory bowel disease. Streptococcus mutans is a famous cariogenic bacterium, but a highlyvirulent strain of this bacterium is also associated with inflammatory bowel disease. In this way, both periodontopathic bacteria and cariogenic bacteria are associated with bowel diseases. Further epidemiological studies are necessary to reveal the cause and effect relationship between oral bacterial and bowel diseases.

An increasing number of elderly people in Japan are living in nursing homes. Some of them have strong breath odor, which makes it difficult for the facility workers to perform oral care service. A questionnaire survey was conducted to examine how often the facility workers experience the residents’ oral malodor. The knowledge and consciousness of workers about oral malodor were also examined. Some workers actually experienced oral malodor of the facility residents and hoped that their breath odor could be reduced. The workers understood the causes of oral malodor, but the importance of saliva flow was not well recognized. On the other hand, more than 80% of workers expressed concern about their own breath odor while providing oral care. Nearly 80% of them want to get more information on oral malodor. The results of this questionnaire survey showed that oral malodor is an important matter at care facilities for the elderly, and instruction on oral malodor is necessary for facility workers.

We previously demonstrated that treatment with a globular type of adiponectin (gAd) induced expression of granulocyte colony-stimulating factor (G-CSF) via the MEK/ERK signaling pathway in a murine macrophage cell line, RAW 264. In the present study, we investigated whether suppressor of cytokine signaling-1 (SOCS1) has roles in the regulation of gAd-induced G-CSF generation. Intracellular G-CSF generation induced by gAd treatment peaked after 10h and then attenuated. SOCS1 mRNA and protein were expressed at 1h and 4h after gAd treatment, respectively. Overexpression of SOCS1 reduced G-CSF generation and phosphorylation of ERK, JNK, and p38 MAPK in gAd-treated cells. While gAd treatment induced the translocation of STAT3 to the nucleus under control conditions, STAT3 stayed in the cytosol when SOCS1 was overexpressed. Additionally, knockdown of SOCS1 by interfering RNA caused levels of G-CSF to continue to rise beyond 10h after gAd treatment. These results suggest that SOCS1 is involved in providing negative feedback for gAd-induced production of G-CSF.

Objective: To assess the psychosomatically subjective symptoms of subjects with neurotic tendencies complaining of halitosis. Design: Breath malodour was measured in 368 patients using organoleptic test and gas chromatography. Neurotic tendency and subjective symptoms were assessed using the Cornell Medical Index (CMI). Results: Of the 79 subjects who met the criteria for neurotic tendencies according to CMI scores, 58 (73.4%) had oral malodour, whereas 21 (26.6%) did not. Coated tongue, periodontal pocket, and daily drinking were significantly more common in subjects with oral malodour. On the CMI questionnaire, subjects with no oral malodour more frequently responded ‘yes’ to questions about fatigue and psychological problems in their families. Additionally, many answered that they had perceived their own bad breath. Conclusions: Difficulties experienced by subjects with neurotic tendencies and oral malodour may manifest primarily in oral conditions, whereas those experienced by individuals with neurotic tendencies and no oral malodour may manifest primarily in psychosomatic symptoms.

This study investigated the inhibitory effect of probioticEnterococcus faeciumWB2000 on biofilm formation by cariogenic streptococci. The ability ofE. faeciumWB2000 and JCM5804 andEnterococcus faecalisJCM5803 to inhibit biofilm formation by seven laboratory oral streptococcal strains and 13 clinical mutans streptococcal strains was assayed. TheEnterococcalstrains inhibited biofilm formation in dual cultures with the mutans streptococcal strainsStreptococcus mutansXc andStreptococcus sobrinusJCM5176 (P<0.05), but not with the noncariogenic streptococcal strains.Enterococcus faeciumWB2000 inhibited biofilm formation by 90.0% (9/10) of the clinicalS. mutansstrains and 100% (3/3) of the clinicalS. sobrinusstrains. After culturing, the pH did not differ between single and dual cultures. The viable counts of floating mutans streptococci were lower in dual cultures withE. faeciumWB2000 than in single cultures.Enterococcus faeciumWB2000 acted as a probiotic bacterial inhibitor of cariogenic streptococcal biofilm formation.