著者

Kunihiko Sawada Toshihiko Amemiya Shigenori Hirai Yusuke Hayashi Toshihiro Suzuki Masahiko Honda Johnny Sisounthone Kunihito Matsumoto 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.60, no.1, pp.137-141, 2018 (Released:2018-03-24)

参考文献数

23

被引用文献数

5

---

We compared the diagnostic reliability of 3.0-T magnetic resonance imaging (MRI) for detection of osseous abnormalities of the temporomandibular joint (TMJ) with that of the gold standard, cone-beam computed tomography (CBCT). Fifty-six TMJs were imaged with CBCT and MRI, and images of condyles and fossae were independently assessed for the presence of osseous abnormalities. The accuracy, sensitivity, and specificity of 3.0-T MRI were 0.88, 1.0, and 0.73, respectively, in condyle evaluation and 0.91, 0.75, and 0.95 in fossa evaluation. The McNemar test showed no significant difference (P > 0.05) between MRI and CBCT in the evaluation of osseous abnormalities in condyles and fossae. The present results indicate that 3.0-T MRI is equal to CBCT in the diagnostic evaluation of osseous abnormalities of the mandibular condyle.

著者

Yoshimasa Takeuchi Hiroyasu Koizumi Mika Furuchi Yohei Sato Chikahiro Ohkubo Hideo Matsumura

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.1, pp.1-7, 2018 (Released:2018-03-24)

参考文献数

32

被引用文献数

49

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Accurate impressions are essential in fabri-cating dental restorations and fixed dental prostheses. During the last decade, digital impression systems have improved substantially. This review discusses the accuracy of digital impression systems for fabrication of dental restorations and fixed dental prostheses. A literature search in PubMed was performed for the period from July 2010 through June 2017. The search keywords were Cerec, digital impression, direct digitalization, indirect digitalization, and intraoral scanner. Only relevant studies are summarized and discussed in this review. In general, the latest systems have considerably reduced the time required for impression making, and the accuracy and marginal fit of digital impression systems have recently improved. Restorations and fixed dental prostheses fabricated with currently available digital impression systems and intraoral scanners exhibit clinically acceptable ranges of marginal gap in both direct and indirect procedures.

著者

Ilda P. Ribeiro Joana M. Rodrigues Alexandra Mascarenhas Nadezda Kosyakova Francisco Caramelo Thomas Liehr Joana B. Melo Isabel M. Carreira

出版者

Nihon University School of Dentistry

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

pp.16-0811, (Released:2018-02-26)

参考文献数

54

被引用文献数

7

---

Oral carcinoma develops from squamous epithelial cells by the acquisition of multiple (epi) genetic alterations that target different genes and molecular pathways. Herein, we performed a comprehensive genomic and epigenetic characterization of the HSC-3 cell line through karyotyping, multicolor fluorescence in situ hybridization, array comparative genomic hybridization, and methylation-specific multiplex ligation-dependent probe amplification. HSC-3 turned out to be a near-triploid cell line with a modal number of 61 chromosomes. Banding and molecular cytogenetic analyses revealed that nonrandom gains of chromosomal segments occurred more frequently than losses. Overall, gains of chromosome 1, 3q, 5p, 7p, 8q, 9q, 10, 11p, 11q13, 12, 13, 14, 17, 18p, 20, Yp, and Xq were observed. The largest region affected by copy number loss was observed at chromosome 18q. Several of the observed genomic imbalances and their mapped genes were already associated with oral carcinoma and/or adverse prognosis, invasion, and metastasis in cancer. The most common rearrangements observed were translocations in the centromeric/near-centromeric regions. RARB, ESR1, and CADM1 genes were methylated and showed copy number losses, whereas TP73 and GATA5 presented with methylation and copy number gains. Thus, the current study presents a comprehensive characterization of the HSC-3 cell line; the use of this cell line may contribute to enriching the resources available for oral cancer research, especially for the testing of therapeutic agents.

著者

Tetsuro Watase Kohei Shimizu Hiroki Komiya Kinuyo Ohara Koichi Iwata Bunnai Ogiso

出版者

Nihon University School of Dentistry

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

pp.16-0854, (Released:2018-02-26)

参考文献数

21

被引用文献数

9

---

A study was conducted to evaluate the mechanisms underlying ectopic orofacial pain associated with tooth pulp inflammation in rats. We observed a significant decrease in the head withdrawal threshold (HWT) response to mechanical and heat stimuli applied to the ipsilateral facial skin upon application of complete Freund’s adjuvant (CFA) to the upper first molar (M1TP) in comparison to application of vehicle. A large number of trigeminal ganglion (TG) neurons showed transient receptor potential vanilloid 1 (TRPV1) immunoreactivity (IR), and some of them were retrogradely labeled with fluorogold injected into the facial skin. A large number of cells showing IR for glial fibrillary acidic protein (GFAP) were observed in the 2nd compared to the 1st or 3rd branch regions of the TG, and TG cells innervating the facial skin were also surrounded by GFAP-IR cells. After administration of TRPV1 antagonist into the facial skin of M1TP CFA-treated rats, the decrease of HWTs in response to mechanical and heat stimulation of the facial skin was significantly reversed. The present findings suggest that the excitability of TG neurons is enhanced upon tooth pulp inflammation, leading to overexpression of TRPV1 in TG neurons innervating the facial skin, and that satellite glial cells are also activated, resulting in the development of ectopic orofacial pain.

著者

Niina Tsurumachi Daisuke Akita Koichiro Kano Taro Matsumoto Taku Toriumi Tomohiko Kazama Yoshinao Oki Yoko Saito-Tamura Morio Tonogi Noriyoshi Shimizu Masaki Honda

出版者

Nihon University School of Dentistry

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

pp.16-0786, (Released:2018-02-26)

参考文献数

38

被引用文献数

4

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Dedifferentiated fat (DFAT) cells were isolated from mature adipocytes using the ceiling culture method. Recently, we successfully isolated DFAT cells from adipocytes with a relatively small size (<40 μm). DFAT cells have a higher osteogenic potential than that of medium adipocytes. Therefore, the objective of this study was to determine the optimal concentration of collagenase solution for isolating small adipocytes from human buccal fat pads (BFPs). Four concentrations of collagenase solution (0.01%, 0.02%, 0.1%, and 0.5%) were used, and their effectiveness was assessed by the number of small adipocytes and DFAT cells isolated. The total number of floating adipocytes that dissociated with 0.02% collagenase was 2.5 times of that dissociated with 0.1% collagenase. The number of floating adipocytes with a diameter of ≤29 μm that dissociated with 0.02% collagenase was thrice of those dissociated with 0.1% and 0.5% collagenase. The number of DFAT cells that dissociated with 0.02% collagenase was 1.5 times of that dissociated with 0.1% collagenase. In addition, DFAT cells that dissociated with 0.02% collagenase had a higher osteogenic differentiation potential than those that dissociated with 0.1% collagenase. These results suggest that 0.02% is the optimal collagenase concentration for isolating small adipocytes from BFPs.

著者

Akimasa Tsujimoto Wayne W. Barkmeier Toshiki Takamizawa Hidehiko Watanabe William W. Johnson Mark A. Latta Masashi Miyazaki

出版者

Nihon University School of Dentistry

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

pp.16-0815, (Released:2018-01-29)

参考文献数

40

被引用文献数

13

---

This study evaluated the simulated localized wear of resin luting cements for universal adhesive systems using different curing modes. Five resin luting cements for universal adhesive systems were evaluated and subsequently subjected to wear challenge in a Leinfelder-Suzuki wear simulation device. Overall, 20 specimens from each resin luting cement were photo-cured for 40 s (dual-cure group), and 20 specimens of each material were not photo-cured (chemical-cure group). Simulated localized wear was generated using a stainless steel ball-bearing antagonist in water slurry of polymethylmethacrylate beads. In addition, scanning electron microscopy (SEM) observations of resin luting cements and wear facets were conducted. Significant differences in simulated wear and SEM observations of wear facets were evident among the materials in the dual- and chemical-cure groups. The simulated wear and SEM observations of wear facets of G-CEM LinkForce and Panavia V5 were not influenced by the curing mode. SEM observations of resin luting cements were material dependent. In most cases, dual curing appears to ensure greater wear resistance of resin luting cements than chemical curing alone. The wear resistance of some resin luting cements appears to be material dependent and is not influenced by the curing mode.

著者

Hidekazu Nagashima Masamichi Shinoda Kuniya Honda Noriaki Kamio Akira Hasuike Naoyuki Sugano Yoshinori Arai Shuichi Sato Koichi Iwata

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

pp.16-0830, (Released:2017-10-31)

参考文献数

45

被引用文献数

13

---

Periodontitis caused by bacterial infection gradually progresses accompanied by periodontal tissue destruction. As a result, teeth lose their supporting structures, and this leads to tooth exfoliation. CXC-chemokine receptor 4 (CXCR4) is known to be expressed in lymphocytes, fibroblasts and osteoclasts in periodontal tissues, suggesting that periodontal CXCR4 signaling contributes to alveolar bone resorption in the milieu of periodontitis. However, the role of CXCR4 signaling in the pathogenesis of periodontitis has remained unknown. We established a mouse model of periodontitis by inoculation of Porphyromonas gingivalis (P.g.) into a silk ligature placed around the maxillary molar. Although there was no significant difference in the mechanical sensitivity in the periodontal tissue between P.g. treatment and sham treatment during the experimental period, mechanical allodynia in the periodontal tissue was induced after gingival injection of complete Freund’s adjuvant compared with that resulting from sham and P.g. treatment alone. Moreover, CXCR4 neutralization in the periodontal tissue following P.g. treatment enhanced periodontal inflammatory cell infiltration and depressed alveolar bone resorption. These findings suggest that periodontal CXCR4 signaling in several cell types in P.g.-induced periodontal inflammation depresses alveolar bone resorption in periodontitis. CXCR4 signaling might be a target for therapeutic intervention to prevent alveolar bone resorption in periodontitis.

著者

Taiji Ogawa Mariko Honda-Ogawa Kazunori Ikebe Yumiko Notomi Yoshiko Iwamoto Itsuki Shirobayashi Seiko Hata Masahito Kibi Shizuko Masayasu Satoshi Sasaki Shigetada Kawabata Yoshinobu Maeda

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

pp.16-0722, (Released:2017-10-06)

参考文献数

31

被引用文献数

35

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Over 700 bacterial species have been detected in the oral cavity. Several studies have suggested that periodontitis is associated with systemic disorders such as diabetes mellitus, indicating a key role for oral microbiota in human health. However, the relationship between oral microbiota and diabetes has not been well clarified. Therefore, we conducted microbiome analysis of saliva samples obtained from 15 elderly residents (3 with type 2 diabetes mellitus [DM] and 12 without diabetes [non-DM]) at three different nursing homes, as well as 9 young healthy controls (HC). Genomic DNA was extracted from each sample, and then the V4 region of the 16S rRNA gene was amplified and sequenced. Alpha diversity, in terms of operational taxonomic unit richness, was significantly higher in samples from the non-DM group than in those from the HC group. Weighted UniFrac distance analysis showed that salivary microbial communities in the DM group were separately clustered. Furthermore, in the DM group, Actinomyces and Selenomonas showed significantly higher abundance, whereas Alloprevotella showed significantly lower abundance, relative to the non-DM group. Although our findings were limited by the small sample size, oral bacterial diversity in the DM group was clearly different from that in the non-DM group.

著者

Chieko Mino Toshio Iwata Toshitsugu Kawata

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.3, pp.365-371, 2017 (Released:2017-09-14)

参考文献数

31

被引用文献数

2

---

Residual periodontal ligament (PDL) and cement mass on the roots of extracted teeth are factors that considerably affect tooth transplantation. Therefore, when normal extracted teeth are used for autologous transplantation, it is necessary to regenerate the PDL of the root surface. Here we describe a method to examine human PDL cell adhesion on sterilized root surfaces. Sample teeth were extracted during orthodontic treatment. PDL cells were obtained from healthy periodontal tissue explants from teeth extracted for orthodontic reasons. We developed a method for adhering PDL cells to sterile root surfaces using three-dimensional culture for 3 weeks. We evaluated the adhesion of human PDL cells to the sterilized root surfaces biochemically and histologically. The adherent PDL cells presented new projections on the sterile root surfaces. Therefore, PDL cells can adhere to sterile root surfaces.

著者

Mariko Ohtsu Muneaki Tamura Hideto Sasaki Shuichi Sato Masatake Asano

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.3, pp.453-456, 2017 (Released:2017-09-14)

参考文献数

16

被引用文献数

1

---

The effects of bittern water (BW), obtained from the ocean floor, on cariogenic bacteria and saliva secretion were examined. Streptococcus mutans was mixed with BW for 1, 3, 5, 10, and 20 min to explore the bactericidal effects of BW against cariogenic bacteria. Bacterial viability was calculated by counting the number of colony-forming units on Brain Heart Infusion agar plates. The results indicated a bacterial viability of more than 35% even after 20 min of incubation. Subsequently, the effects of BW on saliva secretion and the salivary concentration of secretory IgA (sIgA) were examined. Gargling with BW significantly augmented saliva secretion. Although the sIgA concentration was reduced, the total sIgA secreted into saliva was increased significantly. Our findings indicate that the use of BW may be a new strategy for the treatment of various oral diseases, including dry mouth.

著者

Tomoyasu Kiyokawa Mitsuru Motoyoshi Mizuki Inaba Remi Sano Akari Saiki Go Torigoe Masatake Asano Noriyoshi Shimizu

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.3, pp.447-451, 2017 (Released:2017-09-14)

参考文献数

22

被引用文献数

2

---

The purpose of this experiment was to investigate whether low-intensity pulsed ultrasound (LIPUS) irradiation can inhibit dentoalveolar ankylosis in transplanted rat teeth. LIPUS irradiation (the pulsed ultrasound signal had a frequency of 3.0 MHz, a spatial average intensity of 30 mW/cm2, and a pulse ratio of 1:4) was performed on the face over the re-planted teeth of rats for 4 weeks. After the rats were euthanized, we measured mobility (Periotest value [PTV]) of the transplanted and control teeth using a Periotest. Finally, we performed histological evaluation to detect ankylosis. PTVs tended to be significantly lower for re-planted teeth than for control teeth. Histological evaluation revealed that the roots of all re-planted teeth were coalescent with alveolar bone. Furthermore, no ankylosis was observed in three-fifths of the re-planted teeth following LIPUS irradiation. These results indicate the potential efficacy of LIPUS to inhibit dentoalveolar ankylosis.

著者

Takahisa Murofushi Hiromasa Tsuda Yoshikazu Mikami Yoko Yamaguchi Naoto Suzuki

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.3, pp.415-423, 2017 (Released:2017-09-14)

参考文献数

57

被引用文献数

8

---

SIRT1 is a NAD-dependent histone deacetylase that is important in a wide variety of physiological and pathophysiological processes. Although many studies have examined the relationship between SIRT1 and cancer, the role of SIRT1 in tumor malignancy is controversial. Here, we examined the effects of the SIRT1 activator CAY10591 in gingival epithelial carcinoma Ca9-22 cells. CAY10591 treatment dose- and time-dependently increased SIRT1 level and activity. The treatment decreased cell growth and induced cell-cycle repressor p21 levels. In addition, dimethyl sulfoxide significantly reduced cellular invasion and migration, and CAY10591 enhanced this decrease. Quantitative PCR analysis showed that CAY10591 decreased expression of several invasion/migration promoter genes and induced repressor genes. Our findings suggest that CAY10591 suppresses cell growth and invasion/migration activity in gingival squamous cell carcinoma Ca9-22 cells.

著者

Mayu Nagao Natsuko Tanabe Soichiro Manaka Tadahiro Takayama Takayuki Kawato Go Torigoe Jumpei Sekino Naoya Tsukune Manami Ozaki Masao Maeno Naoto Suzuki Shuichi Sato

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.2, pp.303-309, 2017 (Released:2017-06-22)

参考文献数

51

被引用文献数

12

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Periodontal disease is caused by inflammation induced by Porphyromonas gingivalis (P.g.) lipopolysaccharide (LPS) and involves expression of proinflammatory cytokines such as interleukin (IL)-1, IL-6, tumor necrosis factor-α, and receptor activator of nuclear factor kappa B ligand (RANKL), which are implicated in bone resorption. Low-intensity pulsed ultrasound (LIPUS) is commonly used in the treatment of bone fracture. However, the mechanisms by which LIPUS inhibits LPS-induced inflammatory cytokines are poorly understood. Therefore, we investigated the effects of LIPUS on LPS-induced expression of the proinflammatory cytokines IL-6 and RANKL. MC3T3-E1 cells were incubated in the presence or absence of P.g. LPS and then stimulated with LIPUS for 30 min/day for a maximum of 14 days. LPS increased mRNA and protein expressions of IL-6 and RANKL on day 14. In addition, mRNA expression of COX-2 LPS was higher after 3 and 7 days of LIPUS treatment. PGE2 was induced by LPS after 7 and 14 days of culture. LIPUS suppressed all stimulatory effects of LPS. These results suggest that LIPUS inhibits LPS-induced expression of inflammation cytokines by suppressing PGE2 production and might thus have potential applications in the treatment of periodontitis.

著者

Tsuyoshi Takamura Hisashi Suguro Yoshikazu Mikami Takashi Iwase Yusuke Komiyama Kayo Kuyama Kazuo Komiyama Hiderou Oki

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.2, pp.279-287, 2017 (Released:2017-06-22)

参考文献数

28

被引用文献数

4

---

Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor whose expression level is positively correlated with tumor aggressiveness and metastatic potential. However, the mechanism underlying SLPI-induced enhancement of malignant phenotype is not completely understood. The malignancy of cancer cells is highly dependent on cell migration activity. Our previous study revealed that gingival carcinoma Ca9-22 cells, but not colorectal adenocarcinoma HT-29 cells, expressed SLPI. Therefore, we investigated the migration activity of these two cell types to understand the nature of SLPI-mediated tumor aggressiveness and metastatic potential. In vitro wound healing assay indicated that HT-29 cells and SLPI-deleted Ca9-22 cells showed lower migration activity than wild-type Ca9-22 cells, suggesting that SLPI-induced cell migration plays an important role in tumor aggressiveness and metastatic potential. In addition, our gene expression profiling study based on microarray data for the three cell types identified a number of candidates, including LCP1 and GLI, that could be key molecules in the mechanism of SLPI-induced cell migration.

著者

Tetsuo Ohyama Hiroyasu Yasuda Norio Shibuya Satomi Tadokoro Shinya Nakabayashi Shunsuke Namaki Yaeko Hara Takahiro Ogawa Tomohiko Ishigami

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.2, pp.273-278, 2017 (Released:2017-06-22)

参考文献数

24

被引用文献数

14

---

Previous finite element analyses of peri-implant stress assumed a bone-implant contact (BIC) ratio of 100%, even though the BIC ratio is known to be approximately 50% or less. However, the recent development of ultraviolet treatment of titanium immediately before use, known as photofunctionalization, significantly increased the BIC ratio, to 98.2%. We used a unique finite element analysis model that enabled us to examine the effects of different BIC ratios on peri-implant stress. A three-dimensional model was constructed under conditions of vertical or oblique loading, an implant diameter of 3.3, 3.75, or 5.0 mm, and a BIC ratio of 53.0% or 98.2%. Photofunctionalization and larger implant diameters were associated with reduced stress on surrounding tissues. Under vertical loading, photofunctionalization had a greater effect than increased implant diameter on stress reduction. Under oblique loading, increased implant diameter had a greater effect than photofunctionalization on stress reduction.

著者

Toshimitsu Iinuma Yasumichi Arai Midori Takayama Michiyo Takayama Yukiko Abe Yusuke Osawa Motoko Fukumoto Yusuke Fukui Yohei Shioda Nobuyoshi Hirose Kazuo Komiyama Nobuhito Gionhaku

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.2, pp.207-213, 2017 (Released:2017-06-22)

参考文献数

24

被引用文献数

13

---

Age-related deterioration in physical and oral health reduces healthy life expectancy and is thus an important problem for very elderly people. We investigated the effects of satisfaction with dietary life (SDL) in everyday life on oral health-related quality of life (OHRQoL) and subjective well-being and examined associations between these factors. We evaluated 426 elders aged 85 years or older. All participants completed a questionnaire that inquired about age, gender, drinking status, body mass index, cognitive function, disability, and comorbidities, among other covariates. Oral, physical, and mental health conditions were also examined. Associations of questionnaire results for SDL with items on subjective well-being (Philadelphia Geriatric Center Morale Scale [PGC] and World Health Organization-5 [WHO-5]) and OHRQoL (Geriatric Oral Health Assessment Index [GOHAI]) were confirmed with multiple logistic regression analysis. In a multivariate model adjusted for various confounders, participants with self-reported “enjoyable” SDL had significantly lower risks for having the lowest scores on the GOHAI, PGC, and WHO-5 (odds ratio [OR] = 0.460, 95% confidence interval [CI] = 0.277-0.762; OR = 0.589, 95% CI = 0.348-0.996; and OR = 0.452, 95% CI = 0.263-0.775, respectively). These associations remained after further adjustment for number of teeth.

著者

Yasuki Uchida Mitsuru Motoyoshi Yasuhiro Namura Noriyoshi Shimizu

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.2, pp.257-262, 2017 (Released:2017-06-22)

参考文献数

29

被引用文献数

5

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This study investigated guidelines for placement of monocortical screws in the mandible, particularly the mandibular canal. In this study of 35 patients, we used cone-beam computed tomography to determine the distance from the alveolar crest to the superior border of the mandibular canal (DMC) and the shortest distance from the buccal and lingual cortex to the mandibular canal (attaining distance) in the areas between premolars (premolar area), between the second premolar and first molar (middle area), and between the first and second molars (molar area). The DMC values for these areas were 16.55, 18.94, and 16.58 mm, respectively, and were similar in adults and adolescents. When the attaining distance was 8 mm, the heights on the buccal and lingual sides of the areas were 9 and 16.6 mm, 13.7 and 14.7 mm, and 15.3 and 12 mm, respectively. Risk of proximity to the mandibular canal should be considered at above heights or greater when an orthodontic anchorage device (OAD) 8 mm in length is placed. Careful attention is needed for placements on lingual side in adolescents. By reducing the OAD length to 6 mm, placement safety increases in all areas except the premolar area, especially on the buccal side.

著者

Tadashi Saigusa Yuri Aono John L. Waddington

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.2, pp.195-200, 2017 (Released:2017-06-22)

参考文献数

29

被引用文献数

14

---

The nucleus accumbens is a terminal area of the mesolimbic dopaminergic system that arises in the ventral tegmental area. Opioids are thought to enhance dopaminergic activity in the nucleus accumbens by activating δ- and μ-opioid receptors in the ventral tegmental area. However, δ- and μ-opioid receptor agonists increase extracellular levels of accumbal dopamine when infused directly into the nucleus accumbens of rats. Therefore, the roles of δ- and μ-opioid receptors in regulation of accumbal dopaminergic neural activity have been analyzed by using δ- and μ-opioid receptor ligands. This review describes the mechanisms underlying the stimulatory effects on accumbal dopamine efflux, which are induced by local administration of δ- and μ-opioid receptor agonists into the nucleus accumbens of freely moving rats. The focus of this article is neurochemical studies that use in vivo microdialysis techniques. Taken together, the in vivo neurochemical evidence from these studies indicates that δ- and μ-opioid receptor agonists increase accumbal dopamine efflux by activating naloxone-sensitive opioid receptors, and by mechanisms independent of naloxone-sensitive opioid receptors, in the nucleus accumbens.

著者

Koichi Iwata Ayano Katagiri Masamichi Shinoda

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.2, pp.173-175, 2017 (Released:2017-06-22)

参考文献数

26

被引用文献数

24

---

Excitability of neurons in the trigeminal ganglion (TG), trigeminal spinal subnucleus caudalis (Vc), and upper cervical spinal cord (C1-C2) is greatly enhanced after orofacial inflammation and trigeminal nerve injury, and TG, Vc, and C1-C2 neurons remain sensitized long after such episodes. Sensitized neurons generate various molecules, which are released from nociceptive neurons in these areas and are involved in modulating the excitability of TG, Vc, and C1-C2 nociceptive neurons. Hyperexcitable nociceptive neurons also activate satellite glial cells in the TG and microglial cells and astrocytes in the Vc and C1-C2. Glial cell activation spreads throughout the TG, Vc, and C1-C2 and triggers the release of various molecules involved in modulating nociceptive neurons in TG, Vc, and C1-C2 neurons. These findings suggest that functional interaction between neurons and glial cells is critical in persistent orofacial pain associated with orofacial inflammation and trigeminal nerve injury.

著者

Masayuki Kobayashi Eri Horinuki

出版者

日本大学歯学部

雑誌

Journal of Oral Science (ISSN:13434934)

巻号頁・発行日

vol.59, no.2, pp.167-171, 2017 (Released:2017-06-22)

参考文献数

67

被引用文献数

19

---

Orthodontic tooth movement is accompanied by inflammatory responses in the periodontal ligament. Chemical mediators such as interleukin-1β have key roles in nociception around teeth. Such nociceptive inputs to the periodontal ligament continue for several days and potentially induce plastic changes in higher brain regions, including the cerebral cortex. This review summarizes research on orthodontic treatment-induced modulation of neural activities in the central nervous system. Furthermore, we describe our recent findings on the spatiotemporal effects of orthodontic treatment in the somatosensory and insular cortices.