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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 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 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.

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.

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.

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.

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.

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.

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.

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.

This study aimed to determine the frequency of smoking and to explore factors associated with the smoking habits of female students at a dental hygiene school in Japan. Questionnaires regarding cigarette smoking were given to 168 female students. The response rate was 97.6%. The prevalence of smoking, including current and occasional smokers, was 20.3%. Among family members, only the smoking status of their mother significantly influenced the smoking status of the students. The odds ratio for smoking among dental hygiene students whose mothers were smokers in comparison to students whose mothers were not smokers was 5.1 (95% confidence interval 2.1-12.2, p=0.000). Decision tree analysis showed that the smoking habit of dental hygiene students was correlated with their mothers’ smoking history, as well as the smoking status of junior high school teachers, the smoking habits of close friends and a history of participating in a smoking prevention program when in elementary school. The increased smoking rate of young females, including dental hygienists, is a growing problem in Japan. The smoking statuses of dental hygiene students might be closely influenced by their mothers' smoking status.

Ameloblastoma is the most common benign odontogenic tumor in Japan. It is believed that it expands in the jaw bone through peritumoral activation of osteoclasts by receptor activator of nuclear factor kappa-B ligand (RANKL) released from the ameloblastoma, as in bone metastases of cancer cells. However, the clinical features of ameloblastoma, including its growth rate and patterns of invasion, are quite different from those of bone metastasis of cancer cells, suggesting that different underlying mechanisms are involved. Therefore, in the present study, we examined the possible mechanisms underlying the invasive expansion of ameloblastoma in the jaw bone. Expression levels of RANKL assessed by western blotting were markedly lower in ameloblastoma (AM-1) cells than in highly metastatic oral squamous cell carcinoma (HSC-3) cells. Experiments coculturing mouse macrophages (RAW264.7) with AM-1 demonstrated low osteoclastogenic activity, as assessed by tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cell formation, probably because of low release of RANKL, whereas cocultures of RAW264.7 with HSC-3 cells exhibited very high osteoclastogenic activity. Thus, RANKL release from AM-1 appeared to be too low to generate osteoclasts. However, AM-1 cultured directly on calcium phosphate-coated plates formed resorption pits, and this was inhibited by application of bafilomycin A1. Furthermore, vacuolar-type H+-ATPase (V-ATPase) and H+/Cl- exchange transporter 7 (CLC-7) were detected on the surface of AM-1 cells by plasma membrane biotinylation and immunofluorescence analysis. Immunohistochemical analysis of clinical samples of ameloblastoma also showed plasma membrane-localized V-ATPase and CLC-7 in the epithelium of plexiform, follicular and basal cell types. The demineralization activity of AM-1 was only 1.7% of osteoclasts demineralization activity, and the growth rate was 20% of human normal skin keratinocytes and HSC-3 cells. These results suggest that the slow expansion of several typical types of ameloblastomas in jaw bone is attributable to its slow growth and low demineralization ability.

A composite resin containing surface pre-reacted glass ionomer(S-PRG) has become widely used as filler or other dental materials in dental treatment. In this mini-review, we briefly summarizethe antibacterial activities of S-PRG on different oral bacteria. The inhibitory effect of S-PRG on plaque formation in the oral cavity has been observed. Streptococcus mutans adherence has been shown to be inhibited by S-PRG. S-PRG is also considered to be effective in caries prevention because S-PRG eluate could inhibit biofilm formation and disrupt salivary mature polymicrobial biofilm. S-PRG eluate has suppressed the protease and gelatinase activities of Porphyromonas gingivalis, which is one of the most important periodontopathic bacteria. Coaggregation by P. gingivali sand Fusobacterium nucleatum was also inhibited by S-PRG eluate. Other work has shown that an endodontic sealer containing S-PRGhad an antibacterial effect on some endodontic bacteria. Oral rinsing with S-PRG eluate was also effective in reducing oral malodor production. In this way, S-PRG has antibacterial effect, and it will be further applied for various dental materials and contribute to preventing oral diseases.

We report a case of oral malodor associated with internal resorption. A 39-year-old male attended our hospital complaining of oral malodor. Utilizing organoleptic measurement, the halimeter test and gas chromatography, it was diagnosed as a strong halitosis caused by oral origin. The pocket probing depth of tooth 21 was 10 mm, and X-ray examination revealed a vertical bone loss around this tooth. The patient had received periodontal treatment at two dental offices previously, but the periodontal conditions and oral malodor persisted. We performed an initial periodontal preparation, however a deep pocket remained. We therefore performed a surgical inspection including flap reflection, and found that the tooth had a large perforating defect in the distal surface. The extracted tooth had multiple perforating defects covered with granulation tissues on all root surfaces including the root apex. Taking into consideration the anamnesis and X-ray examination of the extracted tooth, internal absorption was considered to have been the cause of the multiple perforating defects. After extraction of the causative tooth, oral malodor dramatically decreased. To our knowledge, this is the first report of an oral malodor associated with internal resorption. (J. Oral Sci. 48, 89-92, 2006)

Here, we report the management of a type I endoperiodontal lesion with furcation bone loss. A 59-year-old female attended our hospital with the chief complaint of mobility of tooth 46 and recurrent gingival swelling around the tooth. She previously received dental treatment from two dentists, but her condition did not improve. The tooth manifested the symptoms of typical periodontitis, such as gingival swelling, tooth mobility, pus discharge from the periodontal pocket and furcation bone loss. The tooth had no caries and the pulp reacted to an electric pulp test. Careful examination of the gingiva revealed traces of dental fistula. X-ray examination via a gutta percha inserted into the fistula revealed that furcation bone loss was associated with the periapical lesion. We diagnosed a type I endoperiodontal lesion, and applied Periocheck, a detection kit for peptidase-producing bacteria, to check for decreases in bacteria in the furcation and root canals. Soon after non-surgical root canal treatment, the condition of tooth 46 improved without periodontal treatment. After confirming a negative score with Periocheck, the root canal was filled. After 3 months, the furcation bone loss was on the way to recovery. These results indicate that proper diagnosis and confirmation of a decrease in root canal bacteria are important for treating endoperiodontal lesions.

The point of this study was to examine the presence or absence of cytokine-positive cells by means of immunohistochemical methods in the samples of inflamed gingival tissues obtained from an 11-year-old girl with Papillon-Lefevre syndrome (PLS). Interleukin-8 (IL-8)-positive cells were found to be present. In addition, IL-1alpha-and IL-1beta-positive cells were detected. No dysfunction in the phagocytosis and the bacterial killing of peripheral blood polymorphonuclear neutrophils (PMNs) was observed in this patient. Our findings suggest that these cytokines may be members responsible for modulating the process of rapidly progressive periodontitis for patient with PLS.

To examine the effects ofCandidaon halitosis, the carrier state ofCandidawas examined in patients who made a visit with a chief complaint of halitosis.Methods. Subjects were 123 patients (42 males and 81 females) who visited our clinic, with a chief complaint of halitosis. Their average age was 45.8 years. To examine halitosis, an organoleptic test was conducted, and volatile sulfur compounds (VSCs) were measured by gas chromatography. Tongue-coating samples collected at the initial visit were cultured in CHROMagarCandidamedium. The results of aCandidaculture test, an organoleptic test, and VSC measurements were examined.Results. The male-to-female ratio of the patients was about 1 : 2. Patients with severe halitosis accounted for less than 20%. In theCandidaculture test, the positive rate was about 25.2%, andC. albicanswas the most frequently detected. Two kinds ofCandidaspecies were detected in 75% (6/8) of the stronglyCandida-positive group. The VSC measurements were correlated with theCandidaculture test results. Methyl mercaptan concentration was higher in the stronglyC. albicans-positive group or the subjects having two kinds ofCandidaspecies.Conclusion. We suggest that imbalance of oral microbial community exists in the stronglyCandida-positive group.

The infiltration of leukocytes into inflammation sites such as observed in human periapical granulomas is considered to be mediated by chemotactic factors. In this study, we examined the presence of chemokine- and chemokine receptor-positive cells in samples obtained from human subjects by means of immunohistochemical methods. Macrophage chemotactic protein-1 (MCP-1), macrophage inflammatory protein (MIP)-1α, MIP-1β and IFN-inducible protein 10 (IP-10)-producing cells were present in periapical granulomas. In addition, chemokine receptor CCR3-, CCR5-, and CXCR3-positive cells were also present. In contrast, no factor expression was observed in clinically healthy periodontal ligament, serving as a negative control. Our findings suggest that these chemokines are responsible for modulating the process of disease, such as human apical periodontitis.

Background Administration of mercury at nontoxic doses induces systemic autoimmune disease in Brown Norway (BN) rats. The pathogenesis of lupus-like oral mucosal lesion by mercury-induced autoimmunity is still unclear, even though the oral mucosa is observed to be commonly affected in mercury-treated BN rats. In this study, we investigated the immunopathology of lupus-like oral mucosal lesions in a model of mercury-induced systemic autoimmunity. Methods Brown Norway male rats were injected subcutaneously with either phosphate-buffered saline (control) or mercury at a dose of 1.0 mg per kilogram of body weight on days 0, 3, 5, and 7. Blood, kidney, and tongue samples were taken at various timepoints for evaluation by immunohistochemistry, RT-PCR, and lupus band test (LBT). Results Oral mucosal lesions were classified according to three consecutive temporal phases on the basis of infiltration of immunocompetent cells as follows: (phase I) infiltration of MHC class II+ dendritic cells (DC) and macrophages; (phase II) addition of ED1+ macrophage infiltrates; and (phase III) focal infiltration of pan T cells following increased infiltration of DC and macrophages. Dense infiltration of DC and macrophages was observed in the basement membrane (BM) zone of the oral epithelium. Tissue expression of IL-4 mRNA was detected in early lesions (phase I), suggesting that locally produced IL-4 may be responsible for Th2-mediated immune response. A linear and continuous smooth pattern of fluorescence was observed in the oral epithelial BM in addition to renal glomeruli, indicating immune complex deposits. Conclusions Local autoimmune responses are involved in the pathogenesis of mercury-induced lupus-like lesions of the oral mucosa.

Oral malodor, also called halitosis or bad breath, is one of the major complaints made by patients visiting the dentist, ranking behind only dental caries and periodontal disease. It can originate from either systemic or oral conditions, but is usually related to an oral cause. Clinical causes of oral malodor include periodontitis, poor oral hygiene, tongue debris, deep caries, inadequately fitted restorations, endodontic lesions, and low salivary flow [1-5]. Under such conditions, it is thought that either bacterial cell numbers increase or oral bacterial communities shift towards a composition producing high levels of malodor. The major compounds that contribute to oral malodor are volatile sulfur compounds (VSCs), such as hydrogen sulfide (H2S), methyl mercaptan (CH3SH), and dimethyl sulfide (CH3SCH3) [6, 7]. In addition, methylamine, dimethylamine, propionic acid, butyric acid, indole, scatole, and cadaverine are reported to cause oral malodor. About 90% of the VSCs in mouth air are H2S and CH3SH [7], which are produced through bacterial metabolism of sulfur-containing amino acids, such as cysteine and methionine. Gram-negative anaerobes are important producers of VSCs. Persson et al. [8] reported that periodontal pathogens isolated from subgingival plaque, such as Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis and Treponema denticola, generated significant amounts of H2S and CH3SH. An examination of the microbiota composition of the tongue biofilm of individuals with no periodontitis, or only a slight degree of periodontitis, suggested that the major species of H2S-producing bacteria were Veillonella, Actinomyces, and Prevotella [9]. On the other hand, Gram-positive oral bacteria, primarily streptococci, may also promote VSC production by Gram-negative bacteria [10]. Recently, Takeshita et al. [11] determined the bacterial composition of saliva, based on terminal-restriction fragment length polymorphism (T-RFLP) profiles using hierarchical cluster analysis, and associated the global composition of indigenous bacterial populations with the severity of oral malodor. The human oral cavity contains more than 500 bacterial species that interact both with each other and host tissues, suggesting that various bacteria may be related to malodor production. Oral-derived malodor is classified into physiological and pathogenic odor. The microbial composition of the oral cavity varies according to clinical condition; therefore, the most appropriate management strategy may also differ. However, the common goal of regimen for the treatment of oral malodor is the acquisition of a healthy oral condition, including

Both hydrogen sulfide (H2S) and methyl mercaptan (CH(3)SH) are frequently detected in large amounts in malodorous mouth air. We investigated the bacterial composition of saliva of 30 subjects with severe oral malodor exhibiting extreme CH(3)SH/H(2)S ratios (high H(2)S but low CH(3)SH concentrations, n 5 14; high CH(3)SH but low H2S concentrations, n 5 16) and 13 subjects without malodor, using barcoded pyrosequencing analysis of the 16S rRNA gene. Phylogenetic community analysis with the UniFrac distance metric revealed a distinct bacterial community structure in each malodor group. The H2S group showed higher proportions of the genera Neisseria, Fusobacterium, Porphyromonas and SR1 than the other two groups, whereas the CH(3)SH group had higher proportions of the genera Prevotella, Veillonella,Atopobium, Megasphaera, and Selenomonas. Our results suggested that distinct bacterial populations in the oral microbiota are involved in production of high levels of H2S and CH3SH in the oral cavity.

Recently, the antibacterial activity of a composite resin containing prereacted glass ionomer (S-PRG) filler was revealed. We examined the effect of an S-PRG eluate on various biologic activities ofStreptococcus mutansandPorphyromonas gingivalis. Adherence ability ofS. mutanswas evaluated by microtiter plate assay; protease and gelatinase activities ofP. gingivaliswere examined by synthetic substrate hydrolysis and gelatin film spot assay, respectively. Coaggregation ofP. gingivaliswithFusobacterium nucleatumwas also examined. S-PRG eluate was found to suppress streptococcal adherence. S-PRG eluate inhibited the protease and gelatinase activities ofP. gingivalisand the coaggregation betweenP. gingivalisandF. nucleatum. These results indicate that S-PRG eluate suppresses streptococcal adherence and inhibits the protease and coaggregation activities ofP. gingivalis. These findings may prompt research into novel strategies for preventing caries and periodontitis.

Oral malodor develops mostly from the metabolic activities of indigenous bacterial populations within the oral cavity, but whether healthy or oral malodor-related patterns of the global bacterial composition exist remains unclear. In this study, the bacterial compositions in the saliva of 240 subjects complaining of oral malodor were divided into groups based on terminal-restriction fragment length polymorphism (T-RFLP) profiles using hierarchical cluster analysis, and the patterns of the microbial community composition of those exhibiting higher and lower malodor were explored. Four types of bacterial community compositions were detected (clusters I, II, III, and IV). Two parameters for measuring oral malodor intensity (the concentration of volatile sulfur compounds in mouth air and the organoleptic score) were noticeably lower in cluster I than in the other clusters. Using multivariate analysis, the differences in the levels of oral malodor were significant after adjustment for potential confounding factors such as total bacterial count, mean periodontal pocket depth, and tongue coating score ( P < 0.001). Among the four clusters with different proportions of indigenous members, the T-RFLP profiles of cluster I were implicated as the bacterial populations with higher proportions of Streptococcus , Granulicatella , Rothia , and Treponema species than those of the other clusters. These results clearly correlate the global composition of indigenous bacterial populations with the severity of oral malodor.