IL-17, which is produced primarily by Th17 cells, has recently emerged as a key player in the pathogenesis of numerous autoimmune and inflammatory diseases. The effects of IL-17

in temporomandibular disorders(TMD)were investigated using gene expression profiling of synovial fibroblasts isolated from TMD patients. Microarray analysis indicated that CCL8(also called monocyte chemotactic protein 2; MCP-2)was found to be the most highly upregulated gene by IL-17 among the genes with known functions. The MCP chemokines,MCP-1, MCP-2, and MCP-3, have considerable structural homology and are members of the cysteine–cysteine(C-C)chemokine family that mainly modulates monocyte/macrophage recruitment in multiple inflammatory diseases. Real-time PCR analysis showed that the gene expressions of MCP-1, MCP-2, and MCP-3 were significantly higher in IL-17-treated synovial fibroblasts than in non-treated controls. MCP-1 protein production was increased by IL-17 in a time-dependent manner. Additionally, the protein production of MCP-1 was increased by IL-17 treatment in synovial fibroblast samples isolated from three TMD patients. Furthermore, IL-17 signaling was mainly through the NF􀎺B activation pathway for MCP-1 production in synovial fibroblasts. These results suggest that the MCP chemokine production by IL-17 is likely to contribute to promotion of the inflammatory condition in TMD.

To evaluate the apparent diffusion coefficient (ADC) values in normal masticatory muscles with magnetic resonance(MR)imaging.

This study was approved by the ethics committee at the authorsʼuniversity(EC15-12-

009-1). Twenty-seven healthy volunteers(9 men and 18 women; age range, 21–77 years mean age, 53.7 years)who underwent MRI examination of the TMJ at Nihon University School of Dentistry at Matsudo from November 2015 to January 2017 were included in this study. Diffusion-weighted MR images were acquired using a 1.5 T unit with a b factor of 0

and 1000 s/mm², and ADC maps were generated. The ADC values were measured for healthy masticatory muscles. Regions of interest(ROIs)were drawn to completely include the right and left lateral pterygoid, medial pterygoid, and masseter muscles on a slice demonstrating the largest area of each muscle on the ADC maps.

The mean ADC values of the lateral pterygoid muscles, medial pterygoid muscles, and masseter muscles were 1.21±0.31×10^-3 mm²/s, 1.10±0.25×10^-3 mm²/s, and 1.09±

0.23×10^-3 mm²/s, respectively. The ADC values of the lateral pterygoid muscles were significantly higher than those of the medial pterygoid muscles and masseter muscles(*p<

0.05).

The results of this study present the ADC values of the masticatory muscles of healthy subjects in vivo. Data regarding the ADC values for normal masticatory muscles will help facilitate quantitative evaluations of temporomandibular disorders.

This study aimed to compare bite force and masticatory muscle activity between anterior and posterior teeth during first jaw motor performance.

Twenty-six participants performed two biting tasks; one at the anterior teeth(ATB)and one at the right first molar(PTB). The tooth bite task consisted of three force levels(20%,

40% and 60% maximum voluntary contraction(MVC)). Before measurement, participants performed a maximum tooth bite on a force meter to determine the 100% MVC at the anterior and posterior teeth. During all tasks, electromyographic(EMG)activities were recorded from the left and right masseter muscles, and left and right temporalis muscles and bite force were recorded. The variability at each target force level and for each jaw motor task was determined as the coefficient of variation(CV)of the actual bite force activity and EMG activities.

Actual bite force values and EMG RMS amplitude in each muscle were significantly dependent on target force level during ATB and PTB(P<0.01). CV values of actual bite force level in each jaw motor task were not significantly dependent on target force level or biting task. EMG RMS amplitude during ATB and PTB were significantly dependent on force level(P<0.01). In conclusion, our findings suggest that force control of first jaw motor performance did not vary between anterior teeth and posterior teeth. In addition, the present study suggests that the mechanism of force control with regard to jaw movements contributes masticatory muscle activity and periodontal receptors.

Odontogenic maxillary sinusitis primarily results from multiplication of bacteria secondary to dental infection. Since the maxillary premolar and molar roots have the closest proximity to the antral floor, periodontitis of these teeth is the most common cause of odontogenic maxillary sinusitis. The purpose of this study was to evaluate the association between alveolar bone height around the maxillary molar and mucosal thickening of the maxillary sinus using computed tomography(CT)images. We reviewed 679 maxillary sinuses [age 20-92] on CT images performed for dental implant surgery planning or suspected maxillary sinusitis in our department from August 2016 to October 2017. An anatomical relationship between the teeth and maxillary sinus was classified into the following four groups based on the space between the alveolar crest and sinus floor: Group

1, ≧10 mm; Group 2, 7-10 mm; Group 3, 4-7 mm; and Group 4, < 4 mm. CT images were evaluated for mucosal thickening (> 2 mm) of the maxillary sinus floor. There was significant difference of the prevalence of mucosal thickening of maxillary sinus between Groups 1 and 3 and between Groups 1 and 4(P<0.01). The highest incidence of mucosal thickening was seen in Group 4. Our results suggest that alveolar bone height decreasing can increase of mucosal thickening of maxillary sinus.

Background and aim: The cranial base is considered to be related to the growth and development of the maxillofacial structures morphologically, and is regarded as one of the factors in malocclusion. The purpose of this study was to extract morphological characteristics of maxillary retrognathism to analyze relationships among the cranial base,maxilla, and ethmoid and vomer bones constituting the nasal septum.

Materials and methods: Materials were the lateral cephalograms and computed tomography(CT)images of 26 pre-treatment mandibular prognathism patients(Japanese males, 24.8±8.4 years). Subjects were divided into two groups based on the position of point A: a posterior group(n = 10)and an anterior group(n = 16). The posterior group was thought to correspond to maxillary retrognathism. Angular and linear measurements were made on lateral cephalograms and median sagittal plane CT images.

Results: Compared with the anterior group, the posterior group displayed a short anterior cranial base(S-N), a more posteriorly positioned posterior nasal spine, and counterclockwise inclination of the cranial base on cephalometric measurements. The posterior space of the vomer was smaller, and mid-facial height was smaller on CT measurements. No difference between groups was seen in shape of the cranial base or anteroposterior length of the hard palate(ANS-PNS).

Conclusion: The cranial base is inclined counterclockwise due to insufficient growth of the nasal septum, especially the posterior part of the vomer. These morphological factors are suggested to contribute to maxillary retrognathism.

Lateral cephalograms and cone beam computed tomography(CBCT) have been used to examine adenoids. However, these examination methods are invasive because of radiation exposure, and it is unsuitable to screen the young children. An alternative approach may be analysis of voice signals, which contain information on vocal fold vibration and vocal tract morphology. The cepstrum analysis, an acoustic analysis, can extract information on the morphology of the vocal tract. This study aimed to examine adenoids by performing acoustic analysis on nasal sounds.

Fourteen subjects(8 boys and 6 girls; mean age 8.1±1.3 years)were included in the adenoid group and 14 subjects(6 boys, 8 girls, mean age 8.5±1.2 years old)were included as the control group. Lateral cephalogram and CBCT were used for evaluating the anatomical morphology; the wavelength to vocal tract length ratio(WVR)was calculated from the vocal signal of the nasal sound by cepstrum analysis. Then, these parameters were compared between the groups. The identification boundary value of adenoids with WVR was also examined.

A/N, pharyngeal tonsil length, and pharyngeal tonsil thickness was significantly larger ,and distance of narrowest part of the airway, PNS1-PNS2 was significantly smaller in the

adenoid group than the control group.

In cepstrum coefficients 40, 44, 48, 52, and 56, WVR was significantly smaller in the adenoid group. Additionally, in the range of cepstrum coefficients 44 to 56, 80% or more adenoids was expected to be identified.

The findings suggest that cepstrum analysis could be used to examine adenoids noninvasively.

In salivary glands, fluid and ion secretion is mainly regulated by intracellular Ca²⁺.

Muscarinic stimulation evokes rapid increase and sustained elevation of intracellular Ca²⁺,which are due to release of Ca²⁺ from intracellular pool and store-operated Ca²⁺ entry

(SOCE), respectively. Two mouse strains, C57BL/6(B6)and C3H, have been reported to have different sensitivities to caries. C3H, which has a lower sensitivity to caries, have a higher ability to secrete saliva compared with B6. In this study, we compared Ca²⁺ mobilization in submandibular gland cells of the two strains. When cells were stimulated by

1 􀎼M carbachol, there is no significant difference between the peaks of Ca²⁺ response in the two strains. However, the sustained phase of Ca²⁺ elevation was higher in C3H than in B6.

Following stimulation with 10 􀎼M carbachol results in higher peak and sustained phase in C3H compared to in B6. Ca²⁺ elevation induced by the inhibitor of endoplasmic reticular Ca²⁺ pump thapsigargin in Ca²⁺-free medium was higher in C3H than in B6. In contrast,there was no difference in SOCE observed by addition of extracellular Ca²⁺ after depletion of Ca²⁺ by thapsigargin between the two strains. In addition, expression levels of genes that are involved in SOCE were not different between the two strains. These results suggest that the different response of Ca²⁺ elevation is due to the difference in capacity of intracellular Ca²⁺ pool.

To evaluate relationships between apparent diffusion coefficient (ADC) values of masticatory muscles on magnetic resonance imaging(MRI) and temporomandibular joint

(TMJ) disc displacement.

Eighty patients with temporomandibular disorders with bilateral symptoms(16 men, 64

women, range 16-83 years, mean 49.2 years) who underwent MRI from November 2015 to January 2017 were included. MRI techniques used included axial diffusion-weighted imaging and short tau inversion recovery imaging through the neck to the skull base.

Regions-of-interest were drawn that included the entire right and left lateral pterygoid muscles, medial pterygoid muscles, and masseter muscles on a slice demonstrating the largest area of each muscle on an ADC map. Masticatory muscles involved in TMJ disc displacement on sides with reduction were compared with those on sides without reduction, and the effects of gender and age were analyzed.

ADC values of lateral pterygoid muscles and masseter muscles involved in TMJ disc displacement on sides without reduction were significantly higher than those on sides with reduction(*p<0.05). The respective mean ADC values of lateral pterygoid muscles on sides with and without reduction were 1.22×10^－3 mm²/s and 1.28×10^－3 mm²/s, for medial pterygoid muscles they were 1.18×10^－3 mm²/s and 1.20×10^－3 mm²/s, and for masseter muscles they were 1.20×10^－3 mm²/s and 1.24×10^－3 mm²/s.

In lateral pterygoid muscles and masseter muscles involved in disc displacement, ADC values of those on sides without reduction are higher than those on sides with reduction.

Background: Odontogenic maxillary sinusitis primarily results from multiplication of bacteria secondary to dental infection. Because the maxillary premolar and molar roots have the closest proximity to the antral floor, odontogenic infections of these teeth are often the cause of odontogenic maxillary sinusitis. This study aimed to evaluate the associations between the forms of maxillary sinus and maxillary sinus septa and the presence of mucosal thickening of the maxillary sinus using computed tomography(CT).

Methods: In this retrospective study, we reviewed 645 maxillary sinuses [from patients

20-92 years of age]) that were imaged for dental implant surgery planning and suspicion of maxillary sinusitis in our department from August 2016 to October 2017. In our study,maxillary sinuses were classified into four groups based on forms of maxillary sinus and maxillary sinus septa; Group 1: flat(without septa), Group 2: flat(with septa), Group 3:circular and convex(without septa), and Group 4: circular and convex(with septa). CT images were evaluated for mucosal thickening(>2 mm) of the maxillary sinus floor.

Results: Circular and convex forms toward the lower side of the floor of maxillary sinus were significantly associated with mucosal thickening(P<0.01). The presence of maxillary sinus septa was significantly associated with mucosal thickening(P<0.01). The highest incidence of mucosal thickening was observed in Group 4.

Conclusions: The circular and convex form of the floor of maxillary sinus and the presence of maxillary sinus septa can increase mucosal thickening of the maxillary sinus.

Aims: Rough-surfaced dental implants are considered optimum surfaces for osseointegration, but have a high incidence of peri-implantitis. In contrast, machined surface dental implants do not cause peri-implantitis, but enable less osteoblast proliferation and differentiation, which is important in bone forming around the implant. We previously found that synthetic bone mineral(SBM)developed for osteoporosis, accelerates bone forming around rough-surfaced implants in rats. However, the effect of SBM has not been investigated in normal rats without implants. Thus, this study investigated whether SBM is influence in eliciting bone forming in normal rats without implants.

Methods: twenty-four female Wistar normal rats (7 weeks of age) were randomly assigned to receive a control group fed a diet without SBM (n = 12, control) or an experimental group fed a diet with SBM(n=12, experimental). The rats were sacrificed at

11 and 13 weeks. Bone mineral density(BMD)and fluorescent staining were assessed at the distal end of the femur. Between-group differences in BMD at 11 and 13 weeks of age were analyzed.

Results: BMD in cortical bone and cancellous bone was significantly higher in rats who received SBM than those who did not at both 11 and 13 weeks of age. Fluorescence microscopy image of rats who received SBM demonstrated more green fluorescence,compared with rats who did not receive SBM, at both 11 and 13 weeks of age.

Conclusions: Rats who received SBM exhibited increased BMD relative to rats who did not receive SBM, which indicated that the intake of SBM was effective in bone forming.

The aim of the present study was to apply acrylic resin for a removable partial denture

(RPD) with resin clasps. The present study evaluated the changes in retentive forces of resin clasps with different designs composed of acrylic resin or polyester by repeated insertion/removal motion.

Two resin clasp designs(length: 7.5 mm, width: 7.5 mm or 10 mm, thickness: 1.5 mm) made of acrylic resin or polyester(control) were used. An abutment tooth simulating the maxillary first premolar was prepared by using an 18-8 stainless steel model. The amount of undercut of the retentive arms was set at 0.5 mm, with half of the undercut area at the far zone as the contact surface. The initial retentive force and retentive force for each test specimen were measured. The changes of retentive force until 10,000 insertion/removal cycles were measured by an insertion/removal testing apparatus placed in distilled water at 37℃and an insertion load to the abutment tooth of 9.8 N.

The initial retentive force was not significantly different between each test specimen.

During 9,001-9,015 and 10,001-10,015 insertion/removal cycles, the retentive force of acrylic resin clasps with width of 10 mm was significantly higher than that of polyester clasps with width of 7.5 mm(P<0.05).

Our present study may suggest that an RPD with resin clasps composed of acrylic resin with dimensions of length of 7.5 mm, width of 10 mm, and thickness of 1.5 mm with half of the undercut area at the far zone as the contact surface has the potential for use in clinical application.

Yes-associated protein(YAP)and transcriptional coactivator with PDZ-binding motif

(TAZ)are core components in development, homeostasis, and regeneration of tissues via the Hippo signaling pathway, which induces responses such as proliferation and apoptosis of cells. In recent years, the accumulation of YAP and TAZ proteins has been reported during the healing of skin wounds. However, no papers have reported YAP and TAZ expression during the healing of the oral mucosa. The present study used immunohistochemistry(IHC)to examine the localization of YAP and TAZ during the healing of tongue ulcers in mice.

The experiment animals were male ICR mice. The wound was made on each mouseʼs tongue and the tissue was removed upon necropsy. The wounded tissues were subjected to hematoxylin and eosin(HE)staining and to IHC staining using anti-YAP and anti-TAZ antibodies. The IHC staining was scored based on the percentage of positive cells and staining intensity; the two scores were summed to obtain a final score. Analysis targets were epithelium, fibroblasts, inflammatory cells, muscle fibers, and endothelial cells.

YAP- and TAZ-positive cells were observed in the epithelium, muscle fibers, fibroblasts,inflammatory cells, and endothelial cells; high levels of YAP and TAZ expression were seen in the proliferating cells. After the ulcer formed granulated tissue and matured, YAP- and TAZ-positive cells were observed in the epithelium and fibroblasts. Those cells showed high scores during proliferation, with scores gradually decreasing as the granulated tissue matured.

In conclusion, our results demonstrated that YAP and TAZ expression are associated with cell proliferation in the wound healing of the tongue.

Purpose: Although many denture wearers often complain more about pain or irritation in their mandibular ridge mucosa, some patients do not complain pain or dullness even though they have prominet ulcers. However, no investigation has been done yet with the mandibular perception. Thus, this study aimed to investigate the influence of denture wearing on the mandibular nerve by measuring current perception threshold(CPT) and pain threshold(PT), and objectively understand the pain experienced by the denture wearers.

Methods: The CPT and PT values were obtained from the left mental foramen of 40

volunteers(20 edentulous and 20 dentulous) by using the Neurometer CPT/C^® device to deliver electrical stimulation. The PT values were directly proportional to the CPT values.

Results and Discussions: The results showed that edentulous subjects exhibit a change in sensory nerve response to stimulation compared with dentulous subjects. The CPT value of the edentulous subjects was significantly higher. This indicated that the sensation is blunted in these subjects. If the CPT increases, there is a possibility that the subjects will not complain of symptoms even if there is excessive contact of the denture. Those with high CPT as well as PT values are presumed to be less likely to complain of the initial symptoms, but they may later complain of symptoms such as pain.

Conclusion: It suggests that perception is blunted by wearing a denture.

Periodontitis has been associated with an increased risk for atherosclerosis.

Accumulating evidence suggests that endothelical dysfunction is an early marker for atherosclerosis. To determine how periodontal infection could contribute to endothelial dysfunction, we examined the ability of the major periodontal pathogen, Aggregatibacter actinomycetemcomitans (Aa) -sensitized monocytes to modulate properties of human umblical vein endothelial cells(HUVEC) by assessment of reactive oxygen species(ROS) production and apoptosis.

Cell proliferation and apoptosis was measured by BrdU cell proliferation ELISA kit, cell death detection ELISA and caspase activities. Detection of intracellular ROS generation

was evaluated flurometrically using H2DCF-DA. Quantitative reverse transcription polymerase chain reaction was performed using primers specific for p22phox and p47phox.

iNOS, p22phox and p47phox in cell lysates were detected by Western blot analysis with the respective specific antibodies.

Aa did not affect the viability of HUVEC but induced apoptosis in HUVEC cocultured with monocytes. Aa significantly induced ROS and NO productions in monocytes.

Furthermore, Aa increased gene and protein expressions of p22phox, p47phoxand iNOS.

Also, H₂ O₂ induced growth inhibition, apoptosis and caspase 3/7 activities in HUVEC.

These results suggest that apoptosis in HUVEC could be induced by Aa -sensitized monocytes via ROS-dependent pathway, potentially amplifying proatherogenic mechanism in the perturbed vasculature.

Occlusal orthotics are widely used to manage temporomandibular disorder (TMD).

However, the respiratory effects of the use of occlusal orthotics in TMD patients are unclear. The primary purpose of this study was to determine the effect of increased the vertical dimension by an orthotic on the apnea hypopnea index (AHI) and oxygen desaturation index (ODI) of TMD patients. The secondary purpose was to determine whether these effects differed between maxillary and mandibular orthotics.

A total of 26 participants who were diagnosed TMD were recruited for this study. The orthotic group performed the Nox-T3 monitor test to obtain the AHI and the ODI, one night without the use of an orthotic(baseline)and the other night two weeks after they began using an orthotic(follow-up). The control group performed the Nox-T3 monitor test for two nights without the use of an orthotic. The AHI and ODI were compared between the baseline and follow-up. In the orthotic group, half of the patients were randomly allocated to the maxillary orthotic group; the other half were allocated to the mandibular orthotic group. The AHI and ODI were compared between maxillary and mandibular orthotic

groups.

Increasing the occlusal dimension with the orthotic statistically reduced the AHI both in the non-supine and supine positions. Moreover, the maxillary appliance decreased all AHI

and ODI, and mandibular appliance showed the decrease of only AHI.

This study concluded that increase vertical dimension by use of occlusal orthotics in TMD patients reduced respiratory disturbances in non-supine and supine positions.

Possessing sufficient antimicrobial properties in saliva may prevent the excessive growth of fungus and intraoral indigenous bacteria to prevent the oral mucosal disease and pneumonia. The purpose of this study was to clarify the intraday and day-to-day fluctuations of three antimicrobial properties: beta-defensin, histatin, and IgA, which inhibit the growth of C. albicans and intraoral bacteria. Twenty healthy students or workers(10

males and 10 females; 25.7±1.95 years) at Nihon University School of Dentistry at Matsudo were recruited. Resting saliva was collected daily from 10 to 11 AM, and from 15

to 16 PM, for seven days. By using ELISA, individual concentrations(ng/mL) of the antimicrobial properties were examined. The two-way ANOVA analyzed the effect of dayto-day and intraday fluctuations. No significant day-to-day fluctuations in beta-defensin 3(p =0.13), histatin 5(p=0.22), and IgA(p=0.36) were detected. Also, no significant intraday fluctuations of beta-defensin 3(p=0.58) and histatin 5(p=0.70) were detected. However,IgA showed significant low concentration in the morning(p=0.002) than in the afternoon.

The results indicate that the saliva sampling in the morning, rather than the afternoon, is optimal for future studies of host immune factors: beta-defensin, histatin, and IgA.

The purpose of this study is to improve the accuracy of predicting the soft tissue configuration from the change amounts of the hard tissue landmarks in the patients who underwent combined sagittal splitting ramus osteotomy (SSRO) and genioplasty for skeletal mandibular protraction. The samples for this study consisted of the lateral cephalograms records of 20 surgical orthodontics treated patients. The records of each subject were chosen on the basis of their having pre-treatment and post-treatment lateral cephalograms. Landmarks were traced from each film, and scaled to permit radiographic enlargement. The cartesian coordinates of these points were obtained with the use of calipers, where the coordinate set was first translated to bring the midpoint at sella turcica to the origin and then rotated to align the Frankfort horizontal plane with the X axis. Y axis was set perpendicular to the X axis. The means and standard deviations were estimated for each of the cephalometric variables in both the hard tissue and the soft tissue. There were significantly increased in the amount of change in Convexity, ANB, U1 to L1, on the contrary there were significant decreased in SNB, Facial angle, Gonial angle, IMPA. After SSRO and genioplasty there were significant decreased in the X-coordinates of the landmarks in the L1, Id, B, Pog and Me. Regarding the amount of those changes, in the soft tissue measurements, there were significant decreased in X-coordinates of Li, Sid, SB, SPog and SMe.

The results of the regression analysis suggested that the final positions of the points St

(X):0.80, St(Y):0.77, Sid(Y):0.78, SB(Y):0.73, and SPog(Y):0.87, which showed R square greater than 0.70(contribution%), could be predicted with confidence. On the contrary, in the measurement without corresponding hard tissue(Sn and Li), R square were more variable and could be predicted with less confidence.

The prediction of soft tissue profiles in combination with SSRO and genioplasty could be adequately predicted.

The WHO classification defines Ameloblastic fibrodentinoma recognized as developing state of odontomas in 2017 and this tumor is rare. A case of ameloblastic fibrodentinoma in the posterior mandible region is reported. A 28-year-old man was referred to our hospital for treatment of an unclear radiolucent lesion in the right posterior mandible. Radiographic examination showed an unclear radiolucent lesion in the right molar at the mandible. The clinical diagnosis was odontogenic tumor. Conservative surgical excisions were done under the local anesthesia and sedation. Histopathological examination showed a cellular myxomatous stroma including strands of odontogenic epithelium. The final diagnosis was ameloblastic fibrodentinoma. At follow-up evaluation 2 years and 3 months after the procedure, there was no evidence of recurrence.