Purpose The purpose of this study was to evaluate age related and gender related differences by using computed tomography images between the roots of the second molars mandibular cortex and the mandibular canal as well as cortical bone width and mandibular canal diameter in a Japanese population.

Methods 359 patients were subcategorized by gender and age(group Ⅰ＜31 years, group Ⅱ, 31-49 years, group Ⅲ, ＜50 years). The distance between the inner border of the cortical bone and the mandibular canal, the cortical bone width and the mandibular canal diameter were measured on cross sectional images.

Results In male mandibular left, the mandibular second molar distal root apex to superior cortical bone of mandibular canal is shorter in group Ⅱthan in group Ⅲ. Both buccal and lingual cortex width in both sides of the mandible were shorter in younger males than in older males. In females, the mandibular second molar distal root apex to superior cortical bone of mandibular canal was shorter in group I than in group Ⅲin both sides of the mandible. The buccal cortex width was shorter in older females than in younger females.

Conclusion Our study showed that age, gender and region may have influence on the location and size of the mandibular canal as well as cortical bone width in the second molar region among a Japanese population.

Background Wnt signaling is valuable protein network involved in bone metabolism;however, its relationship in bone resorption and formation during orthodontic treatment is currently unknown.

Purpose This study examined Wnt5a expression on the compression side in an in vivo experimental rat tooth movement model. The study then investigated the relation of compression force(CF)to Wnt5a expression from human periodontal ligament(PDL)cells.

Material and Methods In vivo, to movement the maxillary first molar, we added 10 g of orthodontic force to twenty male rats for seven days. We assessed the production of tartrate-resistant acid phosphatase (TRAP) and Wnt5a protein in rats alveolar bone through an immunohistochemical analysis. In vitro, we examined the effect of compression force(CF)on Wnt5a expression using the human PDL(hPDL)cells.

Results We observed resorption lacunae with the multinuclear cells in rat alveolar bone during tooth movement in the 10g group. We observed Wnt5a immunoreactivity on day seven with orthodontic force in the PDL tissue. Wnt5a expression increased for timedependent maner after addition of CF in hPDL cells.

Conclusion Given these findings, the Wnt signaling response to optimum orthodontic force appears to stimulate resorption of alveolar bone in the orthodontic tooth movement.

Wnt signaling plays a vital role in bone metabolism. However, currently, its role in bone formation and resorption during orthodontic tooth movement is still unclear. This studyaimed to investigate in vivo Wnt5a expression in the resorbed root in rats during experimental tooth movement. Eighteen 6-week-old, male Wistar rats were subjected to an orthodontic force of 10 or 50 g for 7 days to induce the mesial movement of the upper first molars. Immunohistochemical analysis was performed to assess tartrate-resistant acid phosphatase, receptor activator of nuclear factor κ-B ligand(RANKL), and Wnt5a protein expressions in the alveolar bone. Additionally, the effects of different compression forces(CFs)on Wnt5a production were investigated using human periodontal ligament(hPDL) cells and human cementoblast-like cells in vitro. Resorption lacunae with multinucleated cells in the CF-10 g group under experimental tooth movement conditions in vivo.Moreover, RANKL and Wnt5a immunoreactivity was detected in the alveolar bone-PDL tissues. In the CF-50 g group, resorption lacunae and RANKL and Wnt5a expressions were detected in PDL-cement tissues. In the in vitro study, 1.0- and 4.0- g CF increased Wnt5a production in hPDL cells and HCEMs, respectively, in a time-dependent manner. These results indicate that the Wnt signaling response to heavy orthodontic forces stimulates the root resorption process during orthodontic tooth movement.

Most mammals possess microstructural decussation in the tooth enamel. The HunterSchreger bands(HSB)are the important microstructure created by differently directed enamel prisms, as observed under a reflective light microscope. The prism decussation of some rhinocerotoids reveals that HSB run vertically along the axis of the tooth. The boundary between the bands is definite in the tangential section. Teleoceras is an extinct rhinocerotoid that was commonly found in the Miocene area of North America. Our observations revealed vertical prism decussation in the inner two-thirds to four-fifths of the Teleoceras molar enamel. The prisms strongly twisted on each axis, and the path of each prism undulated at the border of the bands. Their relative relations revealed inclinational changes and displacement to the adjacent zone of the HSB. Reconstructed threedimensional images were used for complementation of microscopic observations.

A previous study showed that vaccinia virus-vectored pentavalent H5N1 influenza vaccine adjuvanted with IL-15 injected via the parenteral route induced broadly effective protective immunity. However, influenza virus is known to infect the mucosal surfaces of the respiratory tract, and nasal immunization induces effective protective immunity against respiratory tract infection. Therefore, we explored the vaccine potential of nasal immunization with the vaccinia virus-vectored multivalent pandemic influenza vaccine candidate. BALB/c mice were nasally immunized with the Wyeth strain of vaccinia virusbased pentavalent H5N1 vaccine adjuvanted with IL-15 or Wyeth virus. Four weeks after the first immunization, the mice received a booster, and antigen(Ag)-specific antibody (Ab)and cellular immune responses induced in the vaccinated mice were analyzed 3 weeks later. Nasal immunization of the pentavalent Wyeth-based H5N1 vaccine induced broadly reactive Ag-specific systemic Ab responses compared with Wyeth-vaccinated mice. The secretory IgA Ab response was induced in the lower respiratory tract, although the degree of induction was marginal. The number of IFN-γ-producing cells, and the frequencies of IFN-γ⁺ CD4⁺, TNF-α⁺ CD4⁺ and TNF-α⁺ CD8⁺ T cells were significantly increased in the lungs of mice immunized with Wyeth-based H5N1 vaccine. The results of this study suggested that although the immunogenicity of Wyeth-based pentavalent H5N1 vaccine expressing IL-15 was insufficient as a mucosal vaccine, cellular immunity was preferentially induced in the respiratory mucosal compartment, which is the site of influenza virus infection, when the vaccine was delivered via the nasal mucosa.

The assessment of parafunctional behaviors is an essential baseline examination because those behaviors can cause repetitive trauma to the masticatory system. The purpose of this study was to examine whether changes in oral parafunctional behaviors are related to the natural course of temporomandibular disorder(TMD). The parafunctional behaviors were assessed by the Oral Behavior Checklist(OBC), a subjective list of 21 parafunctional behaviors. Symptoms of TMD were assessed by a self-reporting diagnostic tool, the symptoms questionnaire(SQ). The OBC and SQ questionnaires were administered to 112 students(71 males and 41 females, mean age 22.91±1.99 years)at baseline(BL)and after an 8-month follow-up(FU)period. The chi-squared test was performed to test the null hypothesis that there would be no change in prevalence between symptoms at BL and symptoms at FU.

The null hypothesis, which was that the natural course of the variety of the OBC tertile group(a group shift to a lower score tertile group, a group shift to a higher score tertile group, and the absence of a group shift after the 8-month FU period) would not be associated with the natural course of TMD symptoms, was rejected. There was a statistically significant association between the participants who shifted tertile groups and the natural course of TMD, with respect to pain(p=0.013)and noise(p＞0.00).

Objectives The purposes of this study were to investigate image findings and clinical symptoms of fungal maxillary sinusitis and odontogenic sinusitis, and to assessment of usefulness of differential diagnosis between fungal maxillary sinusitis and odontogenic sinusitis.

Study Design The study included 32 patients (16 fungal sinusitis, 16 odontogenic sinusitis)with a confirmed histopathologic diagnosis of fungal sinusitis or odontogenic sinusitis. Computed tomography(CT)images were used to evaluate such as 1)location and shape of mucosal thickening, 2)calcification, 3)osteolysis, 4)osteosclerosis and 5)thickening of bony wall. Moreover, we investigated clinical symptoms of all patients.

Results There were significant differences between fungal sinusitis and odontogenic sinusitis in sex difference, shape of mucosal thickening, calcification, osteosclerosis,thickening of bony wall and clinical symptoms.

Conclusions This study suggested that these findings are useful for differential diagnosis between fungal maxillary sinusitis and odontogenic sinusitis.

Objectives The purposes of this study were to investigate Computed tomography(CT) imaging findings and clinical symptoms of Nasopalatine duct cyst(NPDC), and to elucidate morphological features of NPDC affects the clinical symptoms.

Study Design The study included 37 patients(24 males, 13 females; age mean 43.8,range12-83)with a confirmed histopathologic diagnosis of NPDC between April 2006 and October 2016. Analysis of spread of cyst and maximum diameter of NPDC were performed on the CT images. Diagnosis of symptoms were made based on clinical interview. Spread of cyst and maximum diameter were compared between patients with and without symptoms using the Mann-Whitney U test. Receiver-operating characteristic(ROC)curve analysis was performed to assess the ability of maximum diameters to predict symptoms.A P-value＜0.05 was considered to indicate statistical significance.

Results Spread of cyst and maximum diameter of NPDC patients with symptoms were significantly higher than that of patients without symptoms(p＜0.05). The accuracies with pain(≥23.9 mm), swelling(≥14.1 mm), and drainage(≥28.6 mm)were 62%, 70% and 73%,respectively.

Conclusions This study suggested that morphological features of NPDC affects the clinical symptoms. The spread and maximum diameter of NPDC using CT can help predict clinical symptoms.

Mechanical cleaning is considered most effective in preventing oral mucosal diseases such as denture stomatitis and aspiration pneumonia; however, host saliva also have effective antimicrobial substances. Beta-defensin and histatin reportedly exert antimicrobial effects against Candida albicans; however, their optimal concentration in human saliva and optimum duration of activity are unclear. Therefore, this study aimed to investigate the effects of concentration and time on the antimicrobial activity of human saliva against C. albicans. Saliva was collected from 20 volunteers(10 men, 10 women; 25.7±1.95 years) twice daily for 1 week, and each antimicrobial substances was quantified. The viable count,ATP activity, and changes in the drug susceptibility test for C. albicans were assessed with respect to different concentrations and durations to analyse antimicrobial activity. Viable count tended to increase with an increase in beta-defensin 3 levels, but tended to decrease with an increase in histatin 5 levels. Yeast density and ATP activity level were significantly positively correlated with each antimicrobial substance(beta-defensin 3; 0.991, p＜.000,histatin 5; 0.975, p＜.000). Beta-defensin 3 and histatin 5 did not yield zones of inhibition with time; however, antifungal drugs reduced the viable count and ATP activity level regardless of time. The present results indicate that histatin 5 reduces the population of C. albicans and ATP activity levels and may be a potential marker for risk assessment of oral mucosal diseases and aspiration pneumonia.

Micro RNAs(miRNAs)are considered to regulate the development and dysfunction of salivary glands. Previous studies on the expression patterns of genes in the primary culture of parotid acinar cells revealed that the isolation process of acinar cells from the glands caused tissue injuries and activated the Src-p38 MAP kinase signaling pathway. While acinar markers were decreased, expression of stem/progenitor markers commenced in the culture. In this study, changes in expression patterns of miRNAs of parotid acinar cells were examined by microarray analysis in order to clarify the mechanism for changes in characteristics of the cells. Analysis on expression values after normalized with robust multi-array averaging method identified that 18 miRNAs were up-regulated and 52 miRNAs were down-regulated after 1-day culture compared with just after isolation.Pathway analysis on the expression-altered miRNAs suggested that they were involved in the regulation of multipotent stem cells. Among the down-regulated miRNAs that were highly expressed, miR-3473, whose fold change was the largest, significantly decreased during the culture for 2 days. Inversely, Sox10, a candidate of target genes for miR-3473,increased during the culture, which was confirmed by real time RT-PCR and immunoblot analyses. Inhibition of Src kinase activity suppressed the changes in expression levels of miR-3473 and Sox10. Since Sox10 is involved in maintenance of stemness and promotes nestin expression, there is a possibility that the down-regulation of miRNAs may regulate acquisition of stemness in parotid acinar cells.

It is very rare that metastatic tumors occur in oral region. Gastric carcinoma is typically asymptomatic, it can be discovered in later stage when it metastases.

54 years old male referred to our department with complaint of a mass(3.5×2.5cm) which was occurred 2 weeks ago, in the vestibule next to left second incisor.

In the extra-oral examination lip was slightly expanded. No lymphadenopathy was determined in the cervical region. No pathological sign was noticed in the medical history.

In radiological examination has been seen radiolucent lesion with irregular margins.

It was considered as primary malign lesion and resected. Histopathological examination revealed high-grade undifferentiated tumor and the patient was scanned with positron emission tomography(PET). PET showed a mass in stomach, metastasis in the peripheral lymph nodes.

Esophagogastroduodenoscopy performed. It revealed necrotic mass in stomach. Biopsy was made and diagnosed, undifferentiated carcinoma. Chemotherapy was given. His health got worse.

Metastatic tumors originating from gastrointestinal system can spread through Batson’s plexus.

When a metastatic tumor occurs as first symptom, it gives an opportunity to cure the disease in early stage. So existence of a malign lesion in oral tissues, it is important to search a possible metastatic relation with any malignancies elsewhere in the body that can lead lethal prognosis.

A nylon partial removable dental prosthesis (PRDP) is aesthetically superior to a traditional PRDP. However, the nylon surface becomes rough after long-term use.

There have been few clinical follow-up reports concerning the re-polished surface after long-term insertion of the nylon PRDP.

We observed the re-polished surface of the nylon denture base with a microscope and a contact profilometer.

This clinical report describes a PRDP constructed from a nylon denture base resin and a metal framework, which obtained a good prognosis during 3.5 years of use. The rough surface of the nylon was improved by re-polishing. However, the deformation of the nylon retentive arm and required relining impeded its long-term use.

We report our experience of florid cemento-osseous dysplasia(FCOD)showing cyst-like findings on Computed tomography(CT)and Magnetic resonance imaging(MRI), along with some literature review. A 36-year-old Japanese woman was referred to department of Oral and Maxillofacial surgery, Nihon University School of Dentistry at Matsudo for a radiolucent lesion in lower right molar area. Pantomogram showed multiple cystic lesions of the mandible. CT demonstrated the well-defined multilocular homogeneous waterdensity lesions in right molar, incisor and left molar areas. No obvious the buccolingual bone expansion and displacement of the inferior alveolar canal due to the lesions were observed. T1-weighted MRI showed low signal intensity lesions. T2-weighted MRI showed heterogeneous high signal intensity lesions. Postcontrast T1-weighted MRI showed low signal intensity lesions with peripheral contrast-enhancement like cystic lesion. These findings led to a suspicion of cystic lesions, and we performed cystectomy. Histopathologically, cellular fibrous stroma with trabecular bone and cementum-like materials were shown. There was no arrangement of osteoblasts around the bony tissue. Dilated blood vessels were also observed in the stroma. The diagnosis of FCOD was established based on the histopathological examination combined with the imaging findings. The postoperative course over two years were uneventful.