著者
Shunichiro Kato Natsuko Tanabe Mayu Nagao Jumpei Sekino Keiko Tomita Mayu Sakai Kimiko Abe Naoto Suzuki Koichiro Ueda
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.20-0010, (Released:2020-08-31)
参考文献数
32
被引用文献数
4

Purpose: Diabetes causes hyperglycemic disorders due to insufficient activity of insulin, and it also increases blood glucose level. Recent studies have reported the relationship between diabetes and periodontal disease. Periodontitis is advanced by inflammatory cytokines stimulated with LPS. The purpose of this study was to investigate the effects of hyperglycemia on the expression of inflammatory cytokines induced by LPS in osteoblasts.Methods: Cells were cultured for 7 and 14 days in the presence or absence of LPS and glucose. The expression mRNA level of IL-6, RANKL and OCN was determined using real-time PCR. The protein expression of IL-6 and RANKL was also measured using ELISA.Results: LPS and glucose increased the mRNA expression of IL-6, coupled with a decrease in the mRNA expression of OCN, which is associated with IL-6 and glucose. It also increased the protein expression of IL-6 compared to LPS. However, LPS+Glucose did not affect the mRNA and protein expression of RANKL. Furthermore, GLUT4 inhibitor, WZB117, blocked the stimulatory effect of glucose on LPS-induced IL-6 mRNA expression. WZB117 did not affect LPS-reduced OCN mRNA expression.Conclusion: These results suggest that high glucose levels increase LPS-induced IL-6 expression mediated by GLUT4.
著者
Futoshi Komine Junichi Honda Kosuke Kusaba Kei Kubochi Hiroki Takata Masanori Fujisawa
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.20-0195, (Released:2020-08-01)
参考文献数
20
被引用文献数
5

Computer-aided design/computer-aided manufacturing (CAD/CAM) restorative materials have been widely used owing to a number of advantages, including stable quality of the materials, lower costs, and time-saving factors. Resin-based CAD/CAM materials for definitive restorations are classified into two groups: dispersed nanoparticle-filled composite resin and polymer-infiltrated-ceramic-network materials. Resin-based CAD/CAM materials have been applied to single crown restorations as a monolithic structure for the posterior region. In addition, resin-based CAD/CAM restorations have been applied recently for the anterior area. This literature review summarizes clinical outcomes, such as survival rates and clinical complications of single crown restorations fabricated with resin-based CAD/CAM materials.
著者
Shumpei Unno Masamichi Shinoda Kumi Soma Asako Kubo Barry J Sessle Tomoyuki Matsui Masatoshi Ando Junichi Asaka Katsuhiko Otsuki Hisashi Yonemoto Hiroki Onose Kousuke Sakanashi Koichi Iwata
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.19-0512, (Released:2020-08-01)
参考文献数
31

To investigate neuronal activity involved in responses to noxious stimuli in conscious monkeys, the animals were subjected to a task that required them to detect a small change in facial skin temperature or light (second temperature: T2, second light: V2) relative to an initial condition (T1 or V1), and to detect changes in V2 along with a heat task. Recordings were obtained from 57 neurons in the ventral premotor cortex (PMv) during the heat or light detection task. T1 neurons and T2 neurons showed increased activity only during T1 or T2, and T1/T2 neurons were activated by both T1 and T2 stimuli. T1/T2 neurons showed an increase in firing at higher T1 temperatures, whereas T1 neurons did not. About half of the non-light/heat-sensitive T1/T2 neurons showed increased firing at higher T2 temperatures, whereas T2 neurons showed no such increase. The heat responses of heat-sensitive PMv neurons were significantly suppressed when monkeys shifted their attention from heat to light. The present findings suggest that heat-sensitive PMv neurons may be involved in motor responses to noxious heat, whereas light/heat-PMv neurons may be involved in emotional and motivational aspects of pain and inappropriate motor responses to allow escape from noxious stimuli.
著者
Takeshi Kase Tetsuo Ohyama Shinya Nakabayashi Hiroyasu Yasuda Takayuki Yoneyama
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.19-0427, (Released:2020-08-01)
参考文献数
25
被引用文献数
1

In this study, analytic models were used to simulate marginal resection in the area of the second premolar to the second molar region, and the mechanical effects on the mandible of residual bone mass, a maxillofacial prosthesis, and a reconstruction plate were evaluated by three-dimensional finite element analysis. As residual bone mass decreased, maximum principal stress increased near the anterior ramus of the mandible, and maximum shear stress increased at the anterior buccal region of the resected area. In the mandible with a maxillofacial prosthesis, the maximum principal stress distribution at the anterior ramus was lower, and the distribution of maximum shear stress at the anterior buccal region of the resected area was higher. When a reconstruction plate was used, maximum principal stress and maximum shear stress were lower. Thus, lower residual bone mass was associated with increased mandible deflection and torsion. In addition, presence of a maxillofacial prosthesis decreased deflection but increased torsion, and presence of a reconstruction plate decreased deflection and greatly decreased torsion. These findings suggest that decreased residual bone mass and maxillofacial prostheses increase fracture risk; however, presence of a reconstruction plate was effective in decreasing torsional stress, thereby reducing fracture risk in the mandible.
著者
Yoshimasa Takeuchi Mika Furuchi Atsushi Kamimoto Kazuya Honda Hideo Matsumura Ryutaro Kobayashi
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.62, no.3, pp.350-351, 2020 (Released:2020-06-23)
参考文献数
6
被引用文献数
34

The outbreak of novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide. Nasopharyngeal swabs are widely used in polymerase chain reaction (PCR) test to detect SARS-CoV-2. However, the collection of nasopharyngeal swabs has a series of drawbacks concerning exposure of healthcare staff, difficulty in collection, and discomfort of patients. Therefore, an alternative noninvasive sample for diagnostic of emerging viral diseases is required. The usefulness of saliva screening tests is compared to conventional swab tests in this report. The results suggest that saliva could be a reliable sample for detecting SARS-CoV-2.
著者
Atsuko Hotta Yasuki Uchida Yasuhiro Namura Mizuki Inaba Mitsuru Motoyoshi
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.62, no.3, pp.318-321, 2020 (Released:2020-06-23)
参考文献数
30

This study used finite element (FE) analysis to investigate the stability of miniscrews (screws) placed at the median palate. FE models with variable suture maturity and screw-suture distances were used to examine the relationship with screw stability. Four groups were classified by extent of maturation of the midpalatal suture (0%, 60%, 75%, and 100%). The placement position was set at the center of the suture (0.0 mm), or 0.5, 1.0, and 1.5 mm to the side of the suture, and von Mises stress values in bone and screw displacement were compared among models. The stress value for the unsutured model, in which the screw was placed at the center of the suture, was greater than 30 MPa. Stress values for models in which screws were placed to the side (0.5-1.5 mm) were less than 28 MPa. Maximum screw displacement was greater in the 0.0-mm incomplete suture model than at other placement positions. Because bone conditions vary among patients, placement position and suture maturation should be examined on cone beam-computed tomography images, to ensure screw stability.
著者
Yusuke Hayashi Motohiro Ito Yusuke Imanishi Kenichiro Watanabe Kunihito Matsumoto Yoshinori Arai Kazuya Honda
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.19-0307, (Released:2020-06-10)
参考文献数
24

The present study used an aluminum phantom to calculate accurate vertical magnification values around the mental foramen on panoramic radiography (PR) and compared corrected PR (Cor-PR) thickness measurements of the aluminum phantom and mandibular cortical width (MCW) of the human head with cone-beam computed tomography (CBCT) measurements at two fields of view (FOVs). The calculated vertical magnification value for PR around the mental foramen was 1.37. Measurements of the aluminum phantom significantly differed between Cor-PR and CBCT with an FOV of 100 mm and between CBCT with FOVs of 40 and 100 mm; however, MCW measurements did not significantly differ among the three methods. There was a very strong correlation between Cor-PR and CBCT with an FOV of 40 mm and between CBCT with FOVs of 40 mm and 100 mm, and intraobserver and interobserver agreement was good-to-excellent for all methods. These results suggest that Cor-PR and CBCT with small and large FOVs are acceptable for measuring MCW.
著者
Eri Sata Leo Takada Ryo Kaetsu Mai Fukasawa Mariko Ohtsu Mitsuru Motoyoshi Masatake Asano
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.19-0477, (Released:2020-06-04)
参考文献数
14
被引用文献数
3

Interleukin-1α (IL-1α) is produced inside cells in its precursor form (pIL-1α). Enzymatic cleavage yields mature (mIL-1α) and the propiece of IL-1α (ppIL-1α), which are thought to be localized in the nucleus, because of the presence of nuclear localizing signals. Studies of ppIL-1α function have been hampered by the lack of a ppIL-1α-specific antibody (Ab). In the present study, the authors generated anti-ppIL-1α Ab by using recombinant histidine-tagged ppIL-1α (His-ppIL-1α) as an immunogen. Rabbits were immunized with His-ppIL-1α, and affinity-purified Ab was obtained. Ab reactivity and specificity were examined by Western blotting. The antibody successfully recognized transfectant-derived green fluorescence protein (GFP)-tagged ppIL-1α but not GFP. A sandwich enzyme-linked immunosorbent assay (ELISA) system established by biotinylating the anti-ppIL-1α Ab successfully detected GFP-ppIL-1α. The Ab and ELISA system allows functional analysis of ppIL-1α and improves understanding of ppIL-1α.
著者
Hideo Matsumura Katsunori Kojima Shigeru Mio Takashi Yamamoto Akihisa Kodaira Hiroyasu Koizumi
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.19-0005, (Released:2020-05-15)
参考文献数
16
被引用文献数
5

The purpose of the current study was to synthesize a methacrylate monomer with a thiohydantoin structure. In a flask, (2-thiohydantoin-4-yl) propionic acid, 10-hyroxydecyl methacrylate, 4-dimethylaminopyridine, and tetrahydrofuran (THF) were placed in a nitrogen atmosphere. A THF solution of N,N’-dicyclohexylcarbodiimide was added and stirred at room temperature. Ethyl acetate and n-hexane were then added to the reaction mixture. The reacted slurry was purified by chromatography with silica gel and hexane-ethyl acetate gradient elution solvent. The structure of the compound was assigned with proton nuclear magnetic resonance spectrum analysis, infrared spectroscopy, and high-resolution mass spectral analysis. The colorless viscous liquid obtained in yield of 49% was characterized as 10-methacryloyloxydecyl-(2-thiohydantoin-4-yl)propionate (MDTHP) or 10-((3-(5-oxo-2-thioxysoimidazolidin-4-yl)propanoyl)oxy)decyl methacrylate (2-THPDM). The MDTHP was soluble to acetone, isopropanol, and methyl methacrylate up to 2.6% or more. This compound could be potentially applicable as a functional monomer for bonding metals and alloys.
著者
Yoshiki Imamura Akiko Okada-Ogawa Noboru Noma Takahiro Shinozaki Kosuke Watanabe Ryutaro Kohashi Masamichi Shinoda Akihiko Wada Osamu Abe Koichi Iwata
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.19-0459, (Released:2020-03-11)
参考文献数
87
被引用文献数
6

Burning mouth syndrome (BMS) is one of the most frequently seen idiopathic pain conditions in a dental setting. Peri- and postmenopausal women are most frequently affected, and patients who experience BMS complain of persistent burning pain mainly at the tip and the bilateral border of the tongue. Recent studies have assessed whether BMS is a neuropathic pain condition, based on morphologic changes in biopsied tongue specimens, and whether there are abnormal pain responses in patients with this disease. Somatosensory studies have reported some abnormal findings in sensory and pain detection thresholds with inconsistency; however, the most distinct finding was exaggerated responses to painful stimuli. Imaging and electrophysiologic studies have suggested the possibility of dysregulation of the pain-modulating system in the central nervous system, which may explain the enhanced pain responses despite the lack of typical responses toward quantitative sensory tests. Basic studies have suggested the possible involvement of neuroprotective steroids, although the underlying mechanisms of this condition have not been elucidated. Experimental studies are looking for preferable supportive therapies for BMS patients despite the obscure pathogenesis.
著者
Shinji Usami Yosuke Yamazaki Maki Yuguchi Yuichi Namba Hirofumi Kanazawa Keitaro Isokawa
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.19-0297, (Released:2020-03-11)
参考文献数
27
被引用文献数
2

The morphogenesis of long bones is a multistep process that generates a variety of genetically defined forms. The tarsometatarsal (TMT) long bone morphology in birds develops through lateral fusion of three initially independent periosteal bone cylinders (BCs). Previous studies have clarified the histological details and chronology of the changes occurring during development. The present study investigated the temporospatial distribution of osteogenic and osteoclastic cells in the embryonic chicken using histochemistry for alkaline phosphatase and tartrate-resistant acid phosphatase, with particular reference to the radial growth of BCs and their subsequent fusion process. Osteogenic cells were localized preferentially in the periosteum of radially growing BCs, leaving open cancellous spaces in the BC wall. Osteoclasts observed later than embryonic day 10 were localized preferentially in the endosteal surface, and therefore the radial growth of BCs resulting from osteoblast activity was accompanied by endosteal resorption by osteoclasts, with progressive enlargement of the bone marrow spaces. During BC fusion, trabecular bridges were formed by periosteal osteogenic cells, with removal of the bone septum by endosteal osteoclasts. These findings suggest that fusion of BCs in the embryonic chicken is mediated by cellular events constituting ordinary long bone development, and not through a defined mechanism specific for fusion.
著者
Masamichi Shinoda Yoshinori Hayashi Asako Kubo Koichi Iwata
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.19-0373, (Released:2020-03-04)
参考文献数
86
被引用文献数
16

Nociceptive stimuli to the orofacial region are typically received by the peripheral terminal of trigeminal ganglion (TG) neurons, and noxious orofacial information is subsequently conveyed to the trigeminal spinal subnucleus caudalis and the upper cervical spinal cord (C1-C2). This information is further transmitted to the cortical somatosensory regions and limbic system via the thalamus, which then leads to the perception of pain. It is a well-established fact that the presence of abnormal pain in the orofacial region is etiologically associated with neuroplastic changes that may occur at any point in the pain transmission pathway from the peripheral to the central nervous system (CNS). Recently, several studies have reported that functional plastic changes in a large number of cells, including TG neurons, glial cells (satellite cells, microglia, and astrocytes), and immune cells (macrophages and neutrophils), contribute to the sensitization and disinhibition of neurons in the peripheral and CNS, which results in orofacial pain hypersensitivity.
著者
Masayuki Kobayashi Yuka Nakaya
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.19-0386, (Released:2020-02-27)
参考文献数
59
被引用文献数
6

Corticofugal projections to neurons in the medullary dorsal horn, i.e., the trigeminal spinal subnucleus caudalis (Sp5C), are thought to play a critical role in regulating nociceptive information processing in the trigeminal nervous system. The Sp5C consists of 5 layers, each of which exhibits its own characteristic features of cellular organization. Therefore, the layers receiving corticofugal projections must be identified when discussing the role of the cerebral cortex in nociception arising from the trigeminal nerve. It is also necessary to discriminate between layers of the Sp5C where corticofugal projections terminate, because the Sp5C involves glutamatergic neurons and GABAergic/glycinergic neurons, which correspond to excitatory and inhibitory neurons, respectively. This review summarizes descending projections from the cerebral cortex, including the primary and secondary somatosensory and insular cortices, to the Sp5C.
著者
Arati S. Panchbhai Shirish S. Degwekar Rahul R. Bhowte
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.52, no.3, pp.359-368, 2010 (Released:2010-09-24)
参考文献数
45
被引用文献数
30 63

Diabetes is known to influence salivary composition and function, eventually affecting the oral cavity. We thus evaluated saliva samples for levels of glucose, amylase and total protein, and assessed salivary flow rate in diabetics and healthy non-diabetics. We also analyzed these parameters with regard to duration and type of diabetes mellitus and gender, and aimed to assess the interrelationships among the variables included in the study. A total of 120 age- and sex-matched participants were divided into 3 groups of 40 each; the uncontrolled diabetic group, the controlled diabetic group and the healthy non-diabetic group. Salivary investigations were performed using unstimulated whole saliva. Mean salivary glucose levels were found to be significantly elevated in both uncontrolled and controlled diabetics, as compared to healthy non-diabetics. There were significant decreases in mean salivary amylase levels in controlled diabetics when compared to healthy non-diabetics. Other than salivary glucose, no other parameters were found to be markedly affected in diabetes mellitus. Further research is needed to explore the clinical implications of these study results. (J Oral Sci 52, 359-368, 2010)
著者
Kunihito Matsumoto Toshihiko Amemiya Motohiro Ito Yusuke Hayashi Kenichiro Watanabe Ko Dezawa Yoshinori Arai Kazuya Honda
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.62, no.1, pp.62-66, 2020 (Released:2020-01-29)
参考文献数
35
被引用文献数
2

This study was performed to develop a new rat model of reduced masticatory activity in order to assess the effect of this reduction on the morphology of the temporomandibular joint (TMJ) over time. Female rats were used, and ovariectomy was performed to simulate aged/postmenopausal status. Twenty-four SD rats aged 6 weeks were divided into four groups: ovariectomy/sham procedure (Ov/S); ovariectomy/reduced masticatory activity (Ov/RMA); non-Ov/S (NO/S); and non-Ov/RMA (NO/RMA). The RMA procedure involved grinding down the edges of the upper and mandibular incisors by about 3 mm and supplying the rats with a powdered diet. The bilateral TMJ was examined by micro-computed tomography at 0, 1, 2, 4, 6, and 8 weeks after the start of RMA. Condylar width was greater in the NO/S group than in the Ov/S group after the 2nd week, showing that ovariectomy reduced the width of the condyle. After the 2nd week, significant differences in condylar width were apparent between the NO/S and NO/RMA groups, and between the Ov/S and Ov/RMA groups. This RMA procedure appeared to provide a good model of reduced masticatory activity. The present findings in female rats suggest that reduction of appropriate mastication activity in the growth period results in poor growth of the mandibular condyle and immediately induces atrophy of the mandibular condyle under conditions simulating aged/postmenopausal status.
著者
Yasuhiro Namura Toshiki Takamizawa Yasuki Uchida Mizuki Inaba Daichi Noma Tomoko Takemoto Masashi Miyazaki Mitsuru Motoyoshi
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.62, no.1, pp.48-51, 2020 (Released:2020-01-29)
参考文献数
20
被引用文献数
8

Although there have been improvements in bracket systems precoated with adhesive, removal of adhesive remnants continues to be problematic. This study compared the hardness and maintainability of precoated adhesive with other commercial adhesives. Knoop hardness values were measured after light- or chemical-induced initial curing, immersion in distilled water at 37°C for 24 h and 1,000 and 10,000 thermal cycles after 24 h. Additionally, the forces required to move brackets by 0.5 mm were measured during bracket positioning, and brackets bonded to bovine enamel were examined by field-emission scanning electron microscopy. The Knoop hardness values of the precoated adhesives were lower than those of commercial resin composite adhesives, and hardness was dependent on the amount of filler in the resin matrix. The ability to maintain the device position may depend on the resin matrix composition. Precoated adhesives with less filler and more matrix material are light curable, and remnant resin may be easily removed.
著者
Sayaka Maruyama Hirofumi Tsutsumi Hikaru Izawa Toshinobu Komuro
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.62, no.1, pp.28-31, 2020 (Released:2020-01-29)
参考文献数
11
被引用文献数
4

This study attempted to determine the minimum number of cells required to conduct DNA analyses effectively. Oral mucosal cells obtained from eight persons were suspended and individually collected by using micromanipulation technique. DNA was extracted and amplified by whole-genome amplification (WGA). Nuclear DNA was extracted to evaluate the feasibility of autosomal short tandem repeat (STR) polymorphism and Y-chromosomal STR polymorphism analyses. Tests were conducted with 20 and 30 cells, to determine the minimum number of cells required for each DNA analysis. Tests with 20 cells were repeated 5 times, to examine reproducibility. When five or 10 cells were used, loci could not be identified for most alleles. Furthermore, DNA polymorphism analyses of a single cell transferred directly to a polymerase chain reaction solution were unsuccessful. The present findings suggest that, in forensic identification, 20 or more cells are required in order to obtain clear results from autosomal and Y-chromosomal STR polymorphism analyses. Furthermore, the feasibility of sample preservation and reexamination was also confirmed by DNA amplification with WGA.
著者
Hidetaka Tsuzuki Yoko Inamoto Eiichi Saitoh Keiko Aihara Seiko Shibata Hitoshi Kagaya Keiko Onogi Enri Nakayama Mitsuyasu Sato Koichiro Ueda
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.62, no.1, pp.18-22, 2020 (Released:2020-01-29)
参考文献数
19
被引用文献数
7

This study used 320-row area detector computed tomography (320-ADCT) to determine whether kinematic swallowing events and bolus movement through the oropharynx are affected by bolus consistency and angle of recline. Fourteen healthy adults (4 men, 10 women; age, 22-90 years) underwent 320-ADCT assessment during three 10-mL barium swallow tests, with honey-thick liquid at 60° recline (60°thick), thin liquid at 60° recline (60°thin), and thin liquid at 45° recline (45°thin). The times of swallowing events were measured and compared among the different tests. Bolus propulsion, onset time of true vocal cord (TVC) closure, and upper esophageal sphincter opening were significantly earlier for 60°thin than for 60°thick. Onset time did not significantly differ between 60°thin and 45°thin; however, greater variability was noted for onset of TVC closure with 45°thin, as the TVC started to close before onset of swallowing in 30% of participants. Modulation of TVC closure depends on bolus transport in different reclining positions. The 45° reclining position elicited pre-swallow TVC closure in some participants, which suggests that excessive recline can increase perceived risk of airway invasion during swallowing.
著者
Jui Yen Chen Asako Kubo Masamichi Shinoda Akiko Okada-Ogawa Yoshiki Imamura Koichi Iwata
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.62, no.1, pp.13-17, 2020 (Released:2020-01-29)
参考文献数
22
被引用文献数
7

Although xerostomia can cause persistent oral pain, the mechanisms underlying such pain are not well understood. To evaluate whether a phosphorylated p38 (pp38)-TRPV4 mechanism in trigeminal ganglion (TG) neurons has a role in mechanical hyperalgesia of dry tongue, a rat model of dry tongue was used to study the nocifensive reflex and pp38 and TRPV4 expression in TG neurons. The head-withdrawal reflex threshold for mechanical stimulation of the tongue was significantly lower in dry-tongue rats than in sham rats. The numbers of TRPV4- and pp38-immunoreactive cells in the TG were significantly higher in dry-tongue rats than in sham rats. Many TRPV4-IR cells were also pp38-immunoreactive. The number of TRPV1-IR cells was unchanged in the TG after induction of tongue dryness. Local injection of a TRPV4 blocker attenuated tongue mechanical hypersensitivity in dry-tongue rats. Intraganglionic injection of a selective p38 MAP kinase inhibitor eliminated tongue hypersensitivity in dry-tongue rats and suppressed TRPV4 expression in TG neurons. The present findings suggest that TRPV4 activation via p38 phosphorylation in TG neurons is involved in mechanical hypersensitivity associated with dry tongue. These mechanisms may have a role in pain associated with xerostomia.
著者
Mizuki Saito Yoshihiro Shimazaki Toshiya Nonoyama Yasushi Tadokoro
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.60, no.4, pp.611-617, 2018 (Released:2018-12-27)
参考文献数
19
被引用文献数
4

The aim of this study was to examine the association between type of dental visit and number of remaining teeth in Japanese elders. Data were collected from 3,163 adults aged 75 or 80 years who underwent an oral health examination. Type of dental visit was classified into four categories by treatment(s) received (none, periodontal, caries, or other treatment). Number of remaining teeth was classified as ≥20, 10-19, or 0-9 teeth. Multivariate multinomial logistic regression analysis was used to examine associations between type of dental visit and number of remaining teeth among all participants and the 3,032 dentate elderly. As compared with elders who did not visit a dentist, those who received periodontal or caries treatments had a significantly lower odds ratio for having 0-9 teeth, and those who received periodontal treatment had a significantly lower odds ratio of having 10-19 teeth. In the multivariate linear regression model, number of days of periodontal treatment was positively associated with number of remaining teeth. Our results suggest that type of dental visit is associated with number of remaining teeth in Japanese elders.