著者
Hiroki Komiya Kohei Shimizu Kae Ishii Hiroshi Kudo Teinosuke Okamura Kohei Kanno Masamichi Shinoda Bunnai Ogiso 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.60, no.4, pp.493-499, 2018 (Released:2018-12-27)
参考文献数
23
被引用文献数
28

Pulpitis often causes referred pain in opposing teeth. However, the precise mechanism underlying ectopic pain associated with tooth-pulp inflammation remains unclear. We performed the present study to test the hypothesis that functional interactions between satellite glial cells (SGCs) and trigeminal ganglion (TG) neurons are involved in ectopic orofacial pain associated with tooth-pulp inflammation. Digastric muscle electromyograph (D-EMG) activity elicited by administration of capsaicin into the upper second molar pulp (U2) was analyzed to evaluate noxious reflex responses. D-EMG activity was significantly increased in rats with lower first molar (L1) inflammation relative to saline-treated rats. Significantly increased expression of glial fibrillary acid protein (GFAP), a marker of activated glial cells, and connexin 43 (Cx43), a gap-junction protein, was observed in activated SGCs surrounding U2-innervating TG-neurons after L1-pulp inflammation. Daily administration of Gap26, a Cx43-inhibiting mimetic peptide, into the TG significantly suppressed capsaicin-induced D-EMG activity enhancement and reduced the percentage of fluorogold-labeled (U2-innervated) cells that were surrounded by GFAP-immunoreactive (IR) and Cx43-IR cells after L1-pulp inflammation. These findings indicate that tooth-pulp inflammation induces SGC activation and subsequent spread of SGC activation in the TG via Cx43-containing gap junctions. Thus, remote neuron excitability becomes enhanced in the TG following tooth-pulp inflammation, resulting in ectopic tooth-pulp pain in the contralateral tooth.
著者
Akiko Okada-Ogawa Naohiko Sekine Kosuke Watanabe Ryutaro Kohashi Sayaka Asano Koich Iwata Yoshiki Imamura
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.17-0453, (Released:2018-12-20)
参考文献数
53
被引用文献数
8

Assessment and treatment of masticatory myofascial pain syndrome (MPS) are not standardized and remain controversial. We examined whether muscle hardness was useful for evaluating masticatory MPS and analyzed the effectiveness of treatments such as stretching and massage (SM) and trigger point injection (TPI). Twenty healthy volunteers and 20 MPS patients were enrolled. MPS patients were divided into TPI and SM treatment groups. Hardness of masticatory muscle with a taut band (TB) and change in hardness were evaluated after SM and TPI treatments. Hardness values were significantly higher in muscle including a TB (TB point) than in the muscle of healthy controls. Visual analogue scale scores were significantly lower after SM and TPI treatments, and hardness of the TB point was significantly lower after SM but not after TPI. These results suggest that measurement of muscle hardness, including the TB, is useful for evaluating masticatory MPS. However, TPI analgesia might not be caused by change in muscle hardness. The mechanisms underlying the effects of SM and TPI on reducing pain in MPS may differ and thus warrant further research.
著者
Verónica Zavala-Alonso Juan P. Loyola-Rodríguez Humberto Terrones Nuria Patiño-Marín Gabriel A. Martínez-Castañón Kenneth Anusavice
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
vol.54, no.1, pp.93-98, 2012 (Released:2012-03-30)
参考文献数
28
被引用文献数
9 18

The aim of this study was to analyze the molecular structure of enamel with fluorosis using micro-Raman spectroscopy and compare it with that of healthy enamel. Eighty extracted human molars were classified into four fluorosis groups according to the Thylstrup-Fejerskov Index (TFI) [TFI: 0, Healthy enamel; 1-3, mild; 4-5, moderate; 6-9, severe fluorosis]. All samples were analyzed by micro-Raman spectroscopy. The integral areas of ν1 (960 cm−1) phosphate peak as well as B-type carbonate peak (1070 cm−1) were obtained to analyze structural differences among the specimens. Although the differences were not statistically significant (P > 0.05), the mean of integral areas of ν1 phosphate peak among groups indicated greater mineralization in the severe fluorosis group. However, there were statistically significant differences in the intensities, and the integral areas of B-type carbonate peak among groups (P < 0.05). Therefore, mineralization of the carbonate peak at 1070 cm−1 decreased significantly in fluorotic groups, suggesting that carbonate ions are easily dissolved in the presence of fluoride. Although structurally fluorotic teeth are not more susceptible to dental caries, serious alteration in its surface topography may cause retention of bacterial plaque and formation of enamel caries. Micro-Raman spectroscopy is a useful tool for analyzing the molecular structure of healthy and fluorotic human enamel. (J Oral Sci 54, 93-98, 2012)
著者
Kae Ishii Keisuke Hatori Osamu Takeichi Kosuke Makino Kazuma Himi Hiroki Komiya 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.17-0439, (Released:2018-11-15)
参考文献数
31
被引用文献数
1

It has been reported that Forkhead box transcription factor class O3a (Foxo3a) is expressed in rheumatoid arthritis, a chronic inflammatory condition accompanied by bone resorption, and plays a role in its pathology. However, it has remained unclear whether Foxo3a is involved in the pathogenesis of periapical granulomas. The present study was performed to compare the expression of Foxo3a in periapical granulomas and healthy gingival tissues. Samples were obtained surgically from patients, and subjected to hematoxylin-eosin staining for histopathologic diagnosis. Two-color immunofluorescence staining was also performed using antibodies against Foxo3a and markers for three types of inflammatory cells: neutrophils, T lymphocytes, and B lymphocytes. This revealed that Foxo3a was expressed in all three cell types in periapical granulomas but not in healthy gingival tissues. Foxo3a was expressed in 82.1%, 78.3%, and 77.5% of neutrophils, T lymphocytes, and B lymphocytes, respectively, and statistical analysis using the Kruskal-Wallis test followed by the Steel-Dwass test showed no significant difference of Foxo3a expression among the three cell types. Our results suggest that Foxo3a transcription factors may be involved in the pathogenesis of periapical granulomas.
著者
Yusuke Miyake Keiji Shinozuka Kosuke Ueki Jun Teraoka Manabu Zama Shouhei Ogisawa Yasuhisa Shinozaki Junya Aoki Keiichi Yanagawa Osamu Shimizu Tadayoshi Kaneko Morio Tonogi Hidero Ohki
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.17-0317, (Released:2018-11-15)
参考文献数
16
被引用文献数
4

To better understand the clinical features of mass lesions of the tongue, we retrospectively evaluated frequency, recurrence rate, and complications in 296 patients who had undergone surgery for such lesions. The diagnoses were fibroma (43.6%), mucous cyst (14.2%), papilloma (11.8%), hemangioma (7.8%), granuloma (6.4%), lipoma (1.4%), schwannoma (1.0%), ectopic tonsil (0.7%), and other (13.2%). Recurrence was noted in two patients (0.7%). Twenty-two patients (7.4%) developed surgical complications, including lingual nerve paralysis (6.4%), glossodynia (0.6%), and postoperative infection (0.3%). Lingual nerve paralysis was observed in the ventral portion (42.1%) of the tongue, apex (36.8%), lateral border (10.5%), and dorsum (10.5%). When all sites were considered together, there was no significant difference in the number of patients presenting with lingual nerve paralysis (P = 0.075). However, there were significant differences in lingual nerve paralysis at the lateral border (P < 0.05), apex (P < 0.05), and dorsum (P < 0.001) but not at the ventral portion (P > 0.05) in the size of the patients with versus without it which suggests that the risk of lingual nerve paralysis is higher at the ventral tongue, regardless of tumor size. These results shed light on the clinical features of mass lesions of the tongue.
著者
Michiko Ichinohe Mitsuru Motoyoshi Mizuki Inaba Yasuki Uchida Mari Kaneko Reiko Matsuike Noriyoshi Shimizu
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.17-0377, (Released:2018-10-26)
参考文献数
35
被引用文献数
19

This study investigated the stability of mini-screws placed in the median palate. The study included 25 patients (7 males, 18 females; mean age, 23.4 ± 5.6 years; age range, 15.0-34.5 years) who had mini-screws placed during orthodontic treatment at Nihon University School of Dentistry Dental Hospital. Mini-screws (diameter, 2.0 mm; length, 9.0 mm) were placed in the median palatal region; the first screw was inserted mesiodistally at the distal contact of the maxillary first molar, and the second screw was placed 6-9 mm mesial to the first screw. Immediately after placement, the placement sites were carefully examined with cone-beam computed tomography and a Periotest device. Screw stability was not related to perforation of the nasal cavity, patient age, or patient sex. The success rate was significantly higher in patients with screw-suture distances of 1.5-2.7 mm than in those with distances of 0-1.4 mm. Moreover, mini-screws could be stabilized when palatal cortical bone thickness was ≥1.5 mm. The success rate was significantly higher in the group with insertion depths of ≥4.5 mm. These results indicate that primary stability of mini-screws requires sufficient cortical bone thickness, insertion depth, and screw-suture distance.
著者
Elaheh Vahid-Dastjerdi Ali Borzabadi-Farahani Mina Mahdian Nazila Amini
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.455-461, 2010 (Released:2010-09-24)
参考文献数
56
被引用文献数
21 48

To investigate the prevalence, characteristics (ie, malocclusion, location, type), and sex distribution of hypodontia in an Iranian orthodontic population. A retrospective study was conducted using periapical and panoramic radiographs and study models of 1,751 subjects attending university orthodontic clinics (870 females, 881 males, age 9-27 years). The Chi-square test was used to analyze differences in the distribution of hypodontia, after stratification by sex and malocclusion type. A total of 197 congenitally missing teeth were observed in 160 patients (9.1%; 74 boys and 86 girls); there were no statistically significant differences between sexes (Chi-square = 0.832, P = 0.36). Hypodontia was more common in patients with Class III malocclusion (45.2%), and was more prevalent in the maxilla (71%) than in the mandible (29%). Maxillary lateral incisors (35.6%) and maxillary second premolars (13.0%) were the most commonly missing teeth, followed by mandibular lateral incisors (9.6%) and mandibular second premolars (8.2%). The prevalence of missing teeth was higher in the anterior segment (incisors and canines) than in the posterior segment (premolars and molars). The prevalence of oligodontia was 0.34%. The prevalence and characteristics of the most frequently missing teeth accorded with the findings of most studies conducted in other countries. (J Oral Sci 52, 455-461, 2010)
著者
Yaeko Hara Hiroshi Shiratsuchi Takaaki Tamagawa Ryosuke Koshi Chihiro Miya Maki Nagasaki Tetsuo Ohyama Shunichi Oka Hideaki Sakashita Tadayoshi Kaneko
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.3, pp.321-328, 2018 (Released:2018-09-23)
参考文献数
31
被引用文献数
7

Recently, reports regarding a foreign body in the maxillary sinus have considerably increased, with the majority being iatrogenic cases resulting from dental treatment. This study involves an extensive review of the Japanese literature, including 112 papers from 1978 to 2017. These papers documented total 407 cases of a foreign body in the maxillary sinus. Among the 392 cases for which treatment details were available, the Caldwell-Luc approach was used for 216, the alveolar approach for 116, extraction using nasal endoscopy for 15, and extraction using oral endoscopy for eight. Spontaneous passage occurred in 19 cases, follow-up with medication was used in 17, and “other” was noted in one. This study determined that surgical removal remains the most common method for treating both tooth roots and other foreign bodies and that the Caldwell-Luc approach is used in majority of the surgeries. No marked differences were noted among the removal methods used in relation to the foreign body type.
著者
Serina Taguchi Futoshi Komine Kei Kubochi Ryosuke Fushiki Fumiaki Kimura Hideo Matsumura
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.17-0383, (Released:2018-08-25)
参考文献数
35
被引用文献数
8

This study examined the effect of silane and phosphate functional monomer on bond strengths between a resin-based luting agent joined to a lithium disilicate ceramic (IPS e.max) and silica (quartz) materials. The e.max and quartz specimens were assigned to 6 groups with different priming/bonding agents, namely, Clearfil Porcelain Bond Activator, Clearfil Photo Bond, Clearfil Photo Bond Universal with Clearfil Porcelain Bond Activator, Clearfil Photo Bond Catalyst with Clearfil Porcelain Bond Activator, Clearfil Photo Bond with Clearfil Porcelain Bond Activator, and unprimed. The corresponding specimens were bonded by using a resin-based luting agent (Panavia V5). Shear bond strengths were determined before and after 5,000 thermocycles. For both the e.max and quartz specimens, the Clearfil Photo Bond Universal with Clearfil Porcelain Bond Activator group had the highest pre- and post-thermocycling bond strength values. Combined use of silane in the acidic environment of a phosphate functional monomer and initiators enhances bond strength of a resin-based luting agent to e.max ceramic and quartz materials.
著者
Miho Obayashi-Ishii Satsuki Saito Daisuke Omagari Masatake Asano Tomohiko Ishigami
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.17-0380, (Released:2018-08-25)
参考文献数
29
被引用文献数
2

Magnetic attachments are commonly used for overdentures. The deleterious effects of exposure to magnetic flux on human health have not been substantiated so far; nevertheless, there is a need to understand the extent of magnetic field exposure in the oral area resulting from the use of magnetic attachments. The purpose of this study was to investigate the influence of a magnetic field on oral squamous cell carcinoma. Tumor cells cultured on a magnetic plate were compared with those not cultured on a magnetic plate (controls). The cells were seeded at a density of 1 × 105 cells/well and cultured for 6 days. The influence of the magnetic field on cytokine production was examined by cytokine array analysis. Secretion of platelet-derived growth factor-AA (PDGF-AA) was measured by enzyme-linked immunosorbent assay and Western blotting. The expression of PDGF-AA messenger RNA was examined by real-time polymerase chain reaction, whereas nuclear factor-kappa B activity was measured by luciferase assay. The results indicated that the magnetic field inhibited the secretion of PDGF-AA, thereby inhibiting PDGF-AA-induced expression, thus reducing the risk of cancer recurrence.
著者
Shigenori Hirai Yusuke Hayashi Motohiro Ito Toshihiko Amemiya Ko Dezawa Yoshinori Arai Ken-ichiro Ejima Shigeki Shimba 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.17-0390, (Released:2018-08-25)
参考文献数
19
被引用文献数
5

Brain and muscle Arnt-like protein-1 (BMAL1) knockout mice exhibit accelerated aging, abnormal glucose metabolism, and impaired adipocyte differentiation, among other phenotypes, which are effects associated with the BMAL1 gene. No study has investigated temporal changes in the deformation of the mandibular condyle and the presence of calcification in areas surrounding the mandibular condyle. In a study of 12 C57/BL strain mice under inhalation anesthesia, we collected images of the mandibular condyle at 6 weeks after birth and then every 5 weeks from 10 to 25 weeks after birth. At 25 weeks, deformation of the mandibular condyle was seen in 8 of 12 joints in BMAL1 knockout mice and in 2 of 12 joints in wild-type mice. At 20 and 25 weeks, deformation in areas surrounding the mandibular condyle, which are known to undergo calcification, was seen in 2 of 12 joints in BMAL1 knockout mice and in 0 of 12 joints in wild-type mice. BMAL1 knockout mice exhibited premature aging of the mandibular condyle, which suggests that circadian rhythms affect mandibular condyle morphology.
著者
Hiroshi Kudo Osamu Takeichi Kosuke Makino Keisuke Hatori 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.17-0412, (Released:2018-08-12)
参考文献数
45
被引用文献数
6

Silent information regulator 2 homolog 1 (SIRT1) inhibits oxidative injury and has anti-inflammatory effects. SIRT1 may be involved in healing of periapical periodontitis; however, SIRT1 expression in periapical periodontitis lesions has not been investigated. This study evaluated SIRT1 expression and a marker of oxidative stress—8-hydroxy-2’-deoxyguanosine (8-OHdG)—in periapical granulomas. First, we used real-time polymerase chain reaction to determine whether U-937 monocytes express SIRT1. U-937 cells treated with the SIRT1 activator resveratrol exhibited the highest SIRT1 mRNA level after 6-h incubation. By contrast, treating cells with the SIRT1 inhibitor sirtinol returned SIRT1 expression level to that of the control. In addition, immunocytochemical analysis using cytospin specimens showed that U-937 cells co-expressed SIRT1 and Ki-67. Dual-color immunofluorescence imaging showed that round cells in periapical granulomas co-expressed SIRT1 and 8-OHdG; however, neither was expressed in healthy gingival tissues. The number of 8-OHdG-expressing cells was significantly greater than the number of SIRT1-expressing cells. Our findings suggest that macrophages express SIRT1 and that wound healing in periapical granulomas is enhanced by a SIRT1-mediated reduction in the level of oxidative stress.
著者
Takanobu Yamamoto Akira Hasuike Ryosuke Koshi Yasumasa Ozawa Manami Ozaki Tatsuya Kubota Shuichi Sato
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.17-0362, (Released:2018-08-12)
参考文献数
16
被引用文献数
3

We used radiological and histological analyses to evaluate the effects of mechanical barrier permeability in a rat model of calvarial guided bone augmentation (GBA). The calvaria of 20 rats were exposed, and one of four types of plastic caps (an occlusive cylindrical plastic cap; a plastic cap with no top; a plastic cap with three holes; and a plastic cap with four holes) was randomly placed on both sides. Newly generated bone in the plastic caps was evaluated with micro-computed tomography (micro-CT) and histological analysis. Micro-CT volumetric analysis and decalcified hematoxylin and eosin-stained sections showed that GBA barrier permeability was inversely associated with the quantity of augmented bone obtained. Masson’s trichrome staining showed that collagen in newly generated bony tissue was more mature in plastic caps with three holes than in those with more-permeable or more-occlusive barriers. Bone augmentation was inhibited in specimens exhibiting invasion of soft tissue through penetrating holes, and barrier permeability was associated with the quantity of augmented bone developed. In conclusion, moderate barrier permeability is optimal for development of mature augmented bone.
著者
Ryosuke Murayama Yuko Nagura Kabun Yamauchi Nobuyuki Moritake Masayoshi Iino Ryo Ishii Hiroyasu Kurokawa Masashi Miyazaki Yumiko Hosoya
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.17-0256, (Released:2018-07-09)
参考文献数
40
被引用文献数
5

We used optical coherence tomography to examine the effect of a coating material containing surface reaction-type pre-reacted glass-ionomer (S-PRG) filler on primary enamel demineralization in 18 extracted human primary teeth. The pulp was removed, and each tooth was ultrasonically cleaned with distilled water. Six teeth were treated with 0.1-M lactic acid buffer solution (De group). In the second group (n = 6), a thin film of coating material was applied before demineralization (PRG group). A third group (Control group; n = 6) was maintained in artificial saliva. Using optical coherence tomography, we measured peak signal intensity (dB) and width at 1/e2 (µm) at predetermined locations on the enamel surface and calculated integrated values. All data were analyzed with ANOVA and the Tukey-Kramer test (α = 0.05). Although changes in integrated values differed between groups, there was a small but significant increase in the Control group and a small but significant decrease in the De group. In the PRG group, integrated values were significantly higher at 7 days after the start of the experiment and significantly increased thereafter. Our findings indicate that a coating material containing S-PRG fillers may prevent primary enamel demineralization.
著者
Kyoko Mukaida Kotoe Mayahara Rina Sanuki-Suzuki Takahiko Tamura Noriyoshi Shimizu
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.2, pp.316-319, 2018 (Released:2018-06-20)
参考文献数
7
被引用文献数
3

For treatment of severe bimaxillary protrusion in adults, a condition known to be among the most difficult to manage, both the maxillary and mandibular anterior teeth must be fully retracted using all the extraction space available. This article reports the treatment of an adult with severe high-angle bimaxillary protrusion. To correct the protrusion of the anterior teeth, orthodontic anchor screws (OASs) were used to provide absolute anchorage during anterior retraction. Acceptable occlusion, facial profile, and balance were achieved. OASs appear to be very useful for treatment of severe bimaxillary protrusion in adults.
著者
Hiroyasu Koizumi Takaya Ishii Tomoyo Okazaki Masahiro Kaketani Hideo Matsumura Takayuki Yoneyama
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.2, pp.285-292, 2018 (Released:2018-06-20)
参考文献数
38
被引用文献数
20

The castability, mechanical properties, and fracture characteristics of Ti-15Mo-5Zr-3Al alloy were compared with those of Ti-6Al-7Nb alloy and pure titanium (CP Ti) for application of this β-type titanium alloy in cast dental prostheses. Cast specimens were prepared with a centrifugal casting machine. A tensile test was performed according to ISO standard 22674. The castability index for Ti-15Mo-5Zr-3Al was lower than those for Ti-6Al-7Nb and CP Ti. The tensile strength of Ti-15Mo-5Zr-3Al was 852 MPa, which was lower than that of Ti-6Al-7Nb and higher than that of CP Ti. The proof strength of Ti-15Mo-5Zr-3Al was 799 MPa, which was comparable to that of Ti-6Al-7Nb and higher than that of CP Ti. The elastic modulus of Ti-15Mo-5Zr-3Al was 81.0 GPa, which was lower than the values for Ti-6Al-7Nb and CP Ti. Elongation of Ti-15Mo-5Zr-3Al was 5.1%, which was comparable to that of Ti-6Al-7Nb and less than that of CP Ti. The shape of the fractured segment was narrower for Ti-15Mo-5Zr-3Al than for Ti-6Al-7Nb and CP Ti. The deformation characteristics of Ti-15Mo-5Zr-3Al may result in decreased stress relative to increased strain during plastic deformation in the stress-strain diagram. In conclusion, Ti-15Mo-5Zr-3Al alloy has a low elastic modulus and exhibits limited ductile plastic deformation in cast dental prostheses.
著者
Moeko Kato Yasuhiro Namura Takayuki Yoneyama Noriyoshi Shimizu
出版者
Nihon University School of Dentistry
雑誌
Journal of Oral Science (ISSN:13434934)
巻号頁・発行日
pp.17-0356, (Released:2018-05-31)
参考文献数
23
被引用文献数
5

This study investigated the effect of the vertical position of the canine on changes in the frictional/orthodontic (F/O) force ratio of nickel-titanium (Ni-Ti) archwires during the initial levelling phase of orthodontic treatment. Frictional and orthodontic forces were measured by using low-friction brackets and Ni-Ti archwires with three different cross-sectional sizes and force types. To simulate canine malocclusion (first premolar extraction case), the upper right canine was displaced gingivally by 1 to 3 mm and the inter-bracket distance between the upper right lateral incisor and second premolar was set at 15 mm or 20 mm. A three-point bending test was performed to measure the orthodontic force of each Ni-Ti archwire. Frictional forces were measured with a universal testing machine and dental arch models by pulling parallel to the end of the archwire at a crosshead speed of 0.5 mm/min. F/O force ratio was calculated and analysed statistically. At a displacement of 3 mm, few archwires had F/O force ratios of less than 1.0, at which orthodontic force overcame frictional force, thus ensuring extrusion of the canine. For effective tooth movement, orthodontists should use Ni-Ti archwires with an F/O force ratio of less than 1.0.
著者
Jun Lee Chisato Yamate Masato Taira Masamichi Shinoda Kentaro Urata Mitsuru Maruno Reio Ito Hiroto Saito Nobuhito Gionhaku Toshimitsu Iinuma 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.17-0238, (Released:2018-05-24)
参考文献数
34
被引用文献数
2

Prefrontal cortex activity is modulated by flavor and taste stimuli and changes during swallowing. We hypothesized that changes in the modulation of prefrontal cortex activity by flavor and taste were associated with swallowing movement and evaluated brain activity during swallowing in patients with dysphagia. To evaluate prefrontal cortex activity in dysphagia patients during swallowing, change in oxidized hemoglobin (z-score) was measured with near-infrared spectroscopy while dysphagia patients and healthy controls swallowed sweetened/unsweetened and flavored/unflavored jelly. Total z-scores were positive during swallowing of flavored/unsweetened jelly and negative during swallowing of unflavored/sweetened jelly in controls but negative during swallowing of sweetened/unsweetened and flavored/unflavored jelly in dysphagia patients. These findings suggest that taste and flavor during food swallowing are associated with positive and negative z-scores, respectively. Change in negative and positive z-scores may be useful in evaluating brain activity of dysphagia patients during swallowing of sweetened and unsweetened food.
著者
Hisashi Suguro Osamu Takeichi Makoto Hayashi Teinosuke Okamura Akiko Hira Yoriyuki Hirano 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.17-0092, (Released:2018-04-16)
参考文献数
25
被引用文献数
4

Transparent epoxy resin root canal models were used to evaluate vertical condensation techniques for obturating lateral canals. The root canal model was configured with a straight main root canal and four right-angled lateral canals at 1.0 and 3.0 mm from the apex. Root canal obturation was performed with Thermafil, Obtura II, or NT condenser. Obturation volume in lateral canals was measured by three-dimensional microcomputed tomography, and one-way analysis of variance was used to analyze differences between groups. Lateral canals at 1.0 and 3.0 mm were uniformly filled by all obturation methods. Among the three obturation methods, Thermafil resulted in the highest obturation volumes for all lateral canals.
著者
Wakako Miyama Yasuki Uchida Mitsuru Motoyoshi Keiko Motozawa Moeko Kato Noriyoshi Shimizu
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.147-153, 2018 (Released:2018-03-24)
参考文献数
28
被引用文献数
3

This study examined the relationship of vertical and horizontal changes in the alveolar bone crest with upper incisor movement after orthodontic treatment. Tooth movement was measured on lateral cephalograms. Vertical and horizontal changes in the median alveolar crest and distance from the cementoenamel junction and anterior nasal spine to the alveolar crest were measured with cone-beam computed tomography. The incisal edge moved distally, and the cervical point intruded significantly and moved distally. The median alveolar crest decreased by 3.80 ± 2.05 mm. The distance from the labial cementoenamel increased significantly, by 0.35 ± 0.38 mm. The vertical distance from the anterior nasal spine decreased significantly, and the alveolar crest moved distally. Vertical tooth movement was positively associated with change in the distance from the labial cementoenamel junction and inversely associated with vertical change in the distance from the anterior nasal spine on the labial and palatal sides. Lingual tooth movement was positively and negatively correlated with horizontal changes in the labial and palatal alveolar crest and vertical change in the palatal alveolar crest. The lingual movement of incisors was related to labial bone resorption. Greater lingual and extrusive movement of incisors led to a greater decrease in the alveolar bone crest.