Wigianto Yoshi Putra Adityakrisna, Megumi Watanabe, Yuki Iwawaki, Takaharu Goto, Otsuki Tamaki and Tetsuo Ichikawa : Antimicrobial Efficacy of a Portable UV-C-Based Coating Activation Device against Candida albicans Biofilm and SARS-CoV-2 as an Additional Feature: An In Vitro Study., Hygiene, Vol.4, No.1, 93-102, 2024.
Kan Nagao, Keiko Fujimoto, Hideki Suito, Takaharu Goto, Yuichi Ishida, Megumi Watanabe and Tetsuo Ichikawa : Effect of Palatal Augmentation Prosthesis on Speech and Swallowing in Tongue Dysfunction:A Literature Review, Journal of Oral Health and Biosciences, Vol.35, No.2, 39-46, 2023.
(要約)
Purpose: Palatal augmentation prosthesis (PAP) is used on patients with dysphagia and dysarthria. While several studies have evaluated the effects of PAP, evidence regarding the adaptation criteria, effects, and limitations of PAP are not well organized. This review aims to summarize its functions, limitations, and applications. Procedure: To investigate the adaptation criteria, effects, and limitations of PAP, we searched the English language literature published in PubMed from its inception through April 20, 2022. The leading search terms included ``palatal augmentation prosthesis.'' Main findings: The primary search used keywords that reflected 31 studies. Finally, nine cross-sectional studies and nine case reports were selected for full-text assessment after applying the inclusion criteria. Eleven studies described the efficacy of speech function: two for motility factors and nine for organic factors (with overlap). Thirteen studies described the effectiveness of swallowing function, four related to motility factors, and ten for organic factors (with overlap). Several studies have demonstrated that PAP effectively restores articulation and swallowing in patients with impaired tongue function after glossectomy for oropharyngeal cancer, sequelae of cranial nerve disease, or neuromuscular disease. However, few papers describe the scope of glossectomy and tongue movement restrictions, so it is impossible to describe the adaptation criteria, effects, and limitations. In this review, most case reports and cross-sectional studies did not provide information on the fabrication methods of PAP or the dentistsʼ experience. Thus, the effect of bias on palatal morphology in PAP patients remains unclear. Conclusions: The number of patients with dysarthria and dysphagia is increasing worldwide, similar to what is already occurring in Japan. Therefore, additional high-quality studies on the effects of PAP are required.
(キーワード)
Palatal augmentation prosthesis / Tongue dysfunction / Literature review
Adityakrisna Putra Yoshi Wigianto, Yuichi Ishida, Yuki Iwawaki, Takaharu Goto, Megumi Watanabe, Kazumitsu Sekine, Kenichi Hamada, Keiji Murakami, Hideki Fujii and Tetsuo Ichikawa : 2-methacryloyloxyethyl phosphorylcholine polymer treatment prevents Candida albicans biofilm formation on acrylic resin, Journal of Prosthodontic Research, Vol.67, No.3, 384-391, 2022.
(要約)
We aimed to evaluate the effectiveness of photoreactive 2-methacryloyloxyethyl phosphorylcholine (MPC) in inhibiting Candida albicans biofilm formation on polymethyl methacrylate (PMMA) and assess its mechanism and need for re-application by evaluating its interaction with salivary mucin and durability during temperature changes. PMMA discs were used as specimens. The MPC coating was applied using the spray and cure technique for the treatment groups, whereas no coating was applied to the control. The MPC treatment (MT) groups were further differentiated based on the number of thermal cycles involved (0, 1000, 2500, and 5000). The optical density was measured to assess mucin adsorption (MA). Contact angle (CA) was calculated to evaluate surface hydrophilicity. The presence of MPC components on the PMMA surface was assessed using X-ray photoelectron spectroscopy (XPS). C. albicans biofilms were evaluated qualitatively (scanning electron microscope images) and quantitatively (colony-forming units (CFUs)). Statistical analysis was conducted using two-way analysis of variance and Tukey's multiple comparison test. MA rate and CA increased significantly in the MT groups, which exhibited significantly fewer CFUs and thinner biofilms than those of the control group. Based on the XPS, MA, and CFU evaluations, the durability and efficacy of the MPC coating were considered stable up to 2500 thermal cycles. Additionally, a significant interaction was observed between mucin concentration and MPC efficacy. The photoreactive MPC coating, which was resistant to temperature changes for approximately 3 months, effectively prevented C. albicans biofilm formation by modifying surface hydrophilicity and increasing mucin adsorption.
Lipei Liu, Megumi Watanabe, Norikazu Minami, Mohammad Fadyl Yunizar and Tetsuo Ichikawa : Semaphorin 3A: A potential target for prevention and treatment of nickel allergy, Communications Biology, Vol.5, No.1, 671, 2022.
(要約)
Metal allergy is one of the typical immune disorders encountered during the application of dental/medical materials and has a highly complex pathogenic mechanism. Semaphorin 3A (Sema3A), a member of the semaphorin family, is reported to be involved in various immune disorders. However, its role in metal allergy has not been clarified yet. Herein, we show that Sema3A expression was upregulated in nickel (Ni) allergy-induced mouse ear tissue and in NiCl-stimulated mouse keratinocytes. Moreover, Sema3A regulated tumor necrosis factor-alpha production and mitogen-activated protein kinase activation in keratinocytes. The specific deletion of Sema3A in keratinocytes did not affect immune cell infiltration but reduced edema and ear swelling; it also impeded Th1 responses to cause a slight alleviation in Ni allergy in mice. Our results demonstrate that Sema3A promotes the development of metal allergy and should be explored as a potential target for the prevention and treatment of metal allergy.
Lipei Liu, Megumi Watanabe, Norikazu Minami, Mohammad Fadyl Yunizar and Tetsuo Ichikawa : Dendritic Cells Directly Recognize Nickel Ions as an Antigen during the Development, Journal of Oral Health and Biosciences, Vol.34, No.2, 40, 2022.
Adityakrisna Putra Yoshi Wigianto, Yuichi Ishida, Takashi Matsuda, Takaharu Goto, Megumi Watanabe and Tetsuo Ichikawa : Novel Magnetic Attachment System Manufactured Using High-Frequency Heat Treatment and Stamp Technique: Introduction and Basic Performance, Dentistry Journal, Vol.10, No.5, 75, 2022.
(要約)
Recently, a novel magnetic attachment with extremely low cost and high performance was developed. This article aims to introduce a novel magnetic attachment and to evaluate its basic eligibility for denture retention in clinical practice. The novel magnetic attachment system used in this study was the direct-bonding root-keeper-type Magteeth™ MT800 (MagneDesign, Nagoya, Japan). The retentive force without displacement (position 0) and after horizontal displacement to positions 0.5, 1, 1.5, 2, 2.5, and 3 mm were measured. The values relative to the retentive force without displacement were gradually decreased to 82.7 ± 16.3%, 68.8 ± 17.1%, 62.4 ± 15%, 47.2 ± 13.1%, 35.7 ± 9.9%, and 20.7 ± 6.5%, respectively. The retentive force and magnetic field strength did not change significantly after the load test (100 N load, 10,000 times). No new gap between the metal and resin was found in the root keeper- and magnet assembly-embedded blocks after the load test. Some scratches on magnetic assembly and root keeper surface, while no change in the resin texture after the load test were observed. Based on the findings of this preliminary study, this novel low-cost magnetic attachment exhibited favorable retention, strength, and durability for clinical use.
Mohammad Fadyl Yunizar, Megumi Watanabe and Tetsuo Ichikawa : Current development status of additive manufacturing technologies for fabricating removable partial denture frameworks: a literature review, International Journal of Computerized Dentistry, Vol.25, No.1, 57-70, 2022.
(要約)
The aim of the present study was to review the current development status of additive manufacturing (AM) technology for fabricating frameworks for removable partial dentures (RPDs) considering fit accuracy, surface condition, and mechanical strength. A search of the databases of MEDLINE, Cochrane Library, and Science Direct was conducted using definite keywords ("removable partial denture" or "framework" or "dental prosthesis design") and ("additive manufacturing technology" or "rapid prototyping" or "3D-printing"). A total of 23 articles were selected according to certain inclusion criteria. The direct AM techniques were applied to manufacture metal RPD frameworks consisting of selective laser melting (SLM), selective laser sintering (SLS), and metal binder jetting (MBJ). The SLM technique showed a good surface and mechanical strength, but low accuracy. The SLS technique showed higher accuracy than indirect AM, but further studies are required. The MBJ technique showed lower accuracy and a rougher surface than the conventional method. AM techniques can produce RPD frameworks within the acceptable range for clinical practice; however, more clinical studies are needed.
Mohammad Fadyl Yunizar, Megumi Watanabe, Lipei Liu, Norikazu Minami and Tetsuo Ichikawa : Metal Allergy Mediates the Development of Oral Lichen Planus via TSLP-TSLPR Signaling, Journal of Clinical Medicine, Vol.11, No.3, 519, 2022.
(要約)
Metal allergy is a T-cell-mediated delayed type of hypersensitive reaction. The pathogenetic mechanisms underlying the allergy are unclear, although the condition has been reported to be related to oral lichen planus (OLP), despite an absence of immunological studies to support this relationship. In this study, histopathological samples of OLP patients were examined to compare the metal allergy-positive and -negative groups, with a focus on the network of epidermal keratinocytes and T cells induced by thymic stromal lymphopoietin (TSLP) and its receptor, TSLPR. Infiltration of T cells into the epithelium was revealed to be higher in the OLP lesions of metal allergy-positive patients than in those of metal allergy-negative patients. Moreover, TSLP-TSLPR signaling and TNF-α production were higher in the epithelial tissue samples of the metal allergy-positive patients than in the metal allergy-negative patients. Metal allergy is associated with both increased expressions of TSLP in keratinocytes and increased TNF-α levels in the epithelium. We propose that this would promote the accumulation of T cells at the lesion site, contributing to the formation of the disease. These results suggest that metal allergy may be an aggravating factor in the pathogenesis of OLP.
Tetsuo Ichikawa, Takaharu Goto, Takahiro Kishimoto, Yuichi Ishida and Megumi Watanabe : Does Prosthodontic Treatment Improve the Nutrition Status in the Elderly? Literature Review, Journal of Food and Nutrition Research, Vol.10, No.1, 26-31, 2022.
Wigianto Yoshi Putra Adityakrisna, Takaharu Goto, Yuki Iwawaki, Yuichi Ishida, Megumi Watanabe and Tetsuo Ichikawa : Treatment outcomes of implant-assisted removable partial denture with distal extension based on the Kennedy classification and attachment type: a systematic review, International Journal of Implant Dentistry, Vol.7, No.1, 111, 2021.
(要約)
Implant-assisted removable partial dentures (IARPDs) have recently become popular, but little information is available on the treatment outcomes based on the Kennedy classification and attachment types. The objective of this review was to evaluate the treatment outcomes of IARPD delivered for distal extension edentulous areas based on the differences in the Kennedy classification and attachment type. English-language clinical studies on IARPD published between January 1980 and February 2020 were collected from MEDLINE (via PubMed), the Cochrane Library (via the Cochrane Central Register of Controlled Trials), Scopus online database, and manual searching. Two reviewers selected the articles based on pre-determined inclusion and exclusion criteria, followed by data extraction and analysis. Eighty-one studies were selected after evaluating the titles and abstracts of 2410 papers. Nineteen studies were finally included after the perusal of the full text. Fourteen studies focused on Class I, 4 studies investigated both Class I and II, and only 1 study was conducted on Kennedy's class II. Eight types of attachments were reported. The ball attachment was the most frequently used attachment, which was employed in 8 of the included studies. The implant survival rate ranged from 91 to 100%. The reported marginal bone loss ranged from 0.3 mm to 2.30 mm. The patient satisfaction was higher with IARPD than with conventional RPDs or that before treatment. The results of prosthetic complications were heterogeneous and inconclusive. IARPD exhibited favorable clinical outcomes when used as a replacement for distal extension edentulous areas. The comparison between the clinical outcomes of Kennedy's class I and II was inconclusive owing to the lack of studies focusing on Kennedy Class II alone. The stud attachment was the most commonly used type in IARPDs. Overall, the different attachment systems did not influence the implant survival rate and patient satisfaction. Further high-quality studies are needed to investigate the attachment systems used in IARPD.
Norikazu Minami, Megumi Watanabe, Lipei Liu, YUNIZAR Fadyl Mohammad and Tetsuo Ichikawa : Effect of Semaphorin7A during the Effector Phase of Nickel Allergy, Journal of Oral Health and Biosciences, Vol.33, No.1, 8-14, 2020.
Takaharu Goto, Nobuaki Higaki, Kazutomo Yagi, Yuichi Ishida, Megumi Watanabe, Kan Nagao and Tetsuo Ichikawa : An innovative masticatory efficiency test using odor intensity in the mouth as a target marker: a feasibility study, Journal of Oral Rehabilitation, Vol.43, No.12, 883-888, 2016.
(要約)
A large number of studies have reported the findings for masticatory efficiency tests; however, some objective masticatory efficiency tests have a drawback, in that subjects are required to spit out the test material. This study examined the possibility of a masticatory efficiency test that evaluates the intensity of odours released when chewing an odour compound-containing material. A total of 20 volunteers were used in this study. The odour intensity in the breath after chewing a gum was measured by portable odour sensor device. The odour intensity after chewing the gum was measured over four chewing durations and at four intervals between spitting out and measurement of the odour intensity. The volume of stimulated saliva was measured by calculating the difference in the weight of the gauze before and after chewing to examine the effect of saliva flow. With an increase in chewing duration, odour intensity reduced. The odour intensity was the highest immediately after chewing. There was a positive correlation between odour intensity and gummy jelly-related masticatory efficiency test value (G-METV), which was significant for 10-s chewing. The regression equation was calculated from three objective variables of odour intensity and G-METV as dependent variable. Pearson's correlation coefficient between G-METV and the odour intensity-related masticatory efficiency value (O-METV) was 0·68. The coefficient of variation of O-METV was significantly lower than that of G-METV. These results suggest that the masticatory performance can be estimated by measuring the odour intensity immediately after chewing food containing odour compounds for 10 s.
Yuichi Ishida, Kumer Kiran, Takaharu Goto, Megumi Watanabe, Wigianto Rudi, Kan Nagao and Tetsuo Ichikawa : Magnet-retained two-mini-implant overdenture: Clinical and mechanical consideration., Dentistry Journal, Vol.4, No.4, 35, 2016.
(要約)
Two-implant overdentures have become the accepted treatment for restoring mandibular edentulism. The dimensions of regular implants sometimes limit their use, such as in the case of narrow ridges. Mini-implants with reduced diameters (less than 3.0 mm) enable insertion into narrow ridges. A magnet-retained two-mini-implant overdenture system was developed and is described in this paper. Additionally, we describe a clinical mandibular procedure using the system and evaluate its biomechanical performance.
Keiko Fujimoto, Norikazu Minami, Takaharu Goto, Yuichi Ishida, Megumi Watanabe, Kan Nagao and Tetsuo Ichikawa : Hardness, cohesiveness, and adhesiveness of oral moisturizers and denture adhesives: selection criteria for denture wearers., Dentistry Journal, Vol.4, No.4, 34, 2016.
(要約)
The mechanical properties of seven denture adhesives and eight oral moisturizers, all of which are commercially available, were evaluated using a texture pro le analysis. A new assessment chart is proposed for the selection criteria of denture adhesive and oral moisturizers using a radar chart with three axes: hardness, cohesiveness, and adhesiveness.
Yuki Iwawaki, Noriko Mizusawa, Takeo Iwata, Nobuaki Higaki, Takaharu Goto, Megumi Watanabe, Yoritoki Tomotake, Tetsuo Ichikawa and Katsuhiko Yoshimoto : MiR-494-3p induced by compressive force inhibits cell proliferation in MC3T3-E1 cells., Journal of Bioscience and Bioengineering, Vol.120, No.4, 456-462, 2015.
(要約)
Mechanical stimuli regulate fundamental cell processes such as proliferation, differentiation, and morphogenesis. We attempted to identify microRNA (miRNA) whose expression is changed during compressive treatment in MC3T3-E1, a pre-osteoblastic cell line. Microarray analysis followed by reverse transcription-quantitative polymerase chain reaction revealed that compressive force at 294 Pa for 24 h in MC3T3-E1 cells increased levels of miR-494-3p, miR-146a-5p, miR-210-3p, and miR-1247-3p. Among these miRNAs, miR-494-3p was found to inhibit cell proliferation in MC3T3-E1 cells. Furthermore, cells subjected to compressive force showed slower cell growth compared with control cells. Levels of mRNA for fibroblast growth factor receptor 2 (FGFR2) and Rho-associated coiled-coil kinase 1 (ROCK1), which were predicted to be targets of miR-494-3p, were decreased by compressive force or overexpression of miR-494-3p mimics in MC3T3-E1 cells. Furthermore, binding sites of miR-494-3p within 3'-untranslated regions of Fgfr2 and Rock1 were determined using luciferase reporter assay. In conclusion, compressive force affected expressions of several miRNAs including miR-494-3p in MC3T3-E1 cells. Compressive force might inhibit cell proliferation in osteoblasts by up-regulating miR-494-3p followed by FGFR2 and ROCK1 gene repressions.
Takaharu Goto, Atsuko Nakamichi, Megumi Watanabe, Kan Nagao, Miwa Matsuyama and Tetsuo Ichikawa : Influence of food volume per mouthful on chewing and bolus properties, Physiology & Behavior, Vol.141, 58-62, 2015.
(要約)
Behaviors relating to food intake, i.e., speed of chewing, number of chews, and bite size, are important for decreasing energy intake, which might reduce excess body weight and thus metabolic risk. This study aimed at investigating the influence of mouthful volume on the number of chews and food bolus properties in addition to clarifying appropriate eating behaviors related to mouthful volume. Fifteen young Japanese women volunteered to participate. The subjects were asked to spit the food bolus in a glass dish just before swallowing when eating 3 different foods: boiled rice, fish sausage, and peanuts. The 3 physical properties of solidity, adhesiveness, and cohesiveness were measured in the bolus, and the number of chews was noted. The number of chews significantly increased with increasing mouthful volume with all 3 foods; conversely, the number of chews per unit of food weight (g) decreased significantly with boiled rice and fish sausage. Trends were observed for solidity and cohesiveness, which varied with increasing mouthful volumes. Decreased mouthful volume resulted in a greater number of chews per weight of food and more appropriate bolus properties; therefore, a change in mouthful volume could be a useful behavior modification for regulation of energy intake.
(キーワード)
Eating / Energy Intake / Feeding Behavior / Female / Food / Humans / Mastication / Young Adult
Ashrin Nur Meinar, Rieko Arakaki, Akiko Yamada, Tomoyuki Kondo, Mie Kurosawa, Yasusei Kudo, Megumi Watanabe, Tetsuo Ichikawa, Yoshio Hayashi and Naozumi Ishimaru : A critical role for thymic stromal lymphopoietin in nickel-induced allergy in mice., The Journal of Immunology, Vol.192, No.9, 4025-4031, 2014.
(要約)
Ni is the most frequent cause of contact allergy induced by metals. However, the underlying mechanism of this induction is unknown. Our previous research demonstrates that activation of dendritic cells (DCs) through p38MAPK/MKK6 is required for Ni-induced allergy in mice. In the current study, we investigated the cellular and molecular mechanisms underlying Ni-induced allergy using a mouse model that involves injecting Ni into the ear, with or without Freund's incomplete or complete adjuvants. Nickel had greater potential to cause allergic reactions compared with palladium and gold. Among the proteins expressed at higher levels in mice with Ni-induced allergy, we focused on thymic stromal lymphopoietin (TSLP), which is produced in abundance by keratinocytes. We detected increased expression of the TSLP receptor (TSLPR) in DCs from cervical lymph nodes of mice with Ni-induced allergy, suggesting that DCs in ear tissues were activated through TSLPR signaling induced by keratinocyte-derived TSLP. Furthermore, delayed-type hypersensitivity reactions in mice with Ni-induced allergy were decreased significantly by injection of a Tslp-short interfering RNA along with atelocollagen in the ear skin. These results suggest that Ni allergy may be triggered by a TSLP/TSLPR-mediated interaction between epithelial and immune cells.
Many studies on surface modifications of titanium have been performed in an attempt to accelerate osseointegration. Recently, anatase titanium dioxide has been found to act as a photocatalyst that expresses antibiotic properties and exhibits hydrophilicity after ultraviolet exposure. A blue-violet semiconductor laser (BV-LD) has been developed as near-ultraviolet light. The purpose of this study was to investigate the effects of exposure to this BV-LD on surface modifications of titanium with the goal of enhancing osteoconductive and antibacterial properties. The surfaces of pure commercial titanium were polished with #800 waterproof polishing papers and were treated with anatase titania solution. Specimens were exposed using BV-LD (λ = 405 nm) or an ultraviolet light-emitting diode (UV-LED, λ = 365 nm) at 6 mW/cm(2) for 3 h. The surface modification was evaluated physically and biologically using the following parameters or tests: surface roughness, surface temperature during exposure, X-ray diffraction (XRD) analysis, contact angle, methylene blue degradation tests, adherence of Porphyromonas gingivalis, osteoblast and fibroblast proliferation, and histological examination after implantation in rats. No significant changes were found in the surface roughness or XRD profiles after exposure. BV-LD exposure did not raise the surface temperature of titanium. The contact angle was significantly decreased, and methylene blue was significantly degraded. The number of attached P. gingivalis organisms was significantly reduced after BV-LD exposure compared to that in the no exposure group. New bone was observed around exposed specimens in the histological evaluation, and both the bone-to-specimen contact ratio and the new bone area increased significantly in exposed groups. This study suggested that exposure of titanium to BV-LD can enhance the osteoconductivity of the titanium surface and induce antibacterial properties, similar to the properties observed following exposure to UV-LED.
Megumi Watanabe and Tetsuo Ichikawa : Analysis of Small GTPases in Dendritic Cells and Keratinocytes in Nickel Allergy Mouse Model, 2013.
26.
Chen Rong Jian, Yoritoki Tomotake, Megumi Watanabe, Yuichi Ishida, Kan Nagao and Tetsuo Ichikawa : Telescopic Magnetic Attachment for Implant-Supported Denture: Evaluation of Splint Effect, The International Journal of Oral & Maxillofacial Implants, Vol.26, No.3, 657-664, 2011.
(要約)
Retrievability, connecting strength, and ease of laboratory work are important but conflicting prerequisites for the success of an implant superstructure, particularly with regard to immediate function. To resolve this issue, a telescopic magnetic attachment system has been developed for implant-supported removable dentures. The splinting effect of the attachment was evaluated for stress distribution and elevation with an in vitro model of three implants in an edentulous mandible. Two types of telescopic magnetic attachments were prepared; the inclination angles of the axial wall of the abutment were 2.5 and 6.0 degrees. Three types of three-unit superstructures--a screw-retained superstructure and two telescopic magnet-retained superstructures--were fabricated. Static loads of 24.5, 49, and 98 N were applied vertically at three loading points on one side of each occlusal table. The elevation was measured as the height at which the magnet-retained superstructure detached from the abutment (on the other side of the prosthesis). In addition, by means of strain gauges, the stress distribution around the implants was evaluated and compared among the superstructures with the same three loads applied at six different points. The magnet-retained superstructure with the axial wall inclined at 2.5 degrees did not detach from the abutment. The differences in stress distribution between the screw-retained and magnet-retained superstructures with a 2.5-degree inclination were found to be statistically insignificant. The magnet-retained superstructure with a 6-degree inclination detached from the abutment, and the stress was concentrated during loading to a cantilever site. Because of its stress distribution and elevation, the new telescopic magnetic attachment, which has properties such as splinting the implants, ease of fabrication, and retrievability, is expected to be a viable alternative for the retention of implant-supported removable dentures.
Megumi Watanabe, Naozumi Ishimaru, Meinar Nur Ashrin, Rieko Arakaki, Akiko Yamada, Tetsuo Ichikawa and Yoshio Hayashi : A Novel DC Therapy with Manipulation of MKK6 Gene on Nickel Allergy in Mice, PLoS ONE, Vol.6, No.4, E19017, 2011.
(要約)
BACKGROUND: Although the activation of dermal dendritic cells (DCs) or Langerhans cells (LCs) via p38 mitogen-activated protein kinase (MAPK) plays a crucial role in the pathogenesis of metal allergy, the in vivo molecular mechanisms have not been identified and a possible therapeutic strategy using the control of dermal DCs or LCs has not been established. In this study, we focused on dermal DCs to define the in vivo mechanisms of metal allergy pathogenesis in a mouse nickel (Ni) allergy model. The effects of DC therapy on Ni allergic responses were also investigated. METHODS AND FINDING: The activation of dermal DCs via p38 MAPK triggered a T cell-mediated allergic immune response in this model. In the MAPK signaling cascade in DCs, Ni potently phosphorylated MAP kinase kinase 6 (MKK6) following increased DC activation. Ni-stimulated DCs could prime T cell activation to induce Ni allergy. Interestingly, when MKK6 gene-transfected DCs were transferred into the model mice, a more pronounced allergic reaction was observed. In addition, injection of short interfering (si) RNA targeting the MKK6 gene protected against a hypersensitivity reaction after Ni immunization. The cooperative action between T cell activation and MKK6-mediated DC activation by Ni played an important role in the development of Ni allergy. CONCLUSIONS: DC activation by Ni played an important role in the development of Ni allergy. Manipulating the MKK6 gene in DCs may be a good therapeutic strategy for dermal Ni allergy.
Hideki Suito, Yoritoki Tomotake, Megumi Watanabe, Daisuke Nagao, Yuichi Ishida and Tetsuo Ichikawa : Survival of immediate implant restoration: A retrospective study through 9-year-observation, Journal of Prosthodontic Research, Vol.55, No.3, 141-145, 2011.
(要約)
The purpose of this retrospective study was to assess the implant survival rate and the risk factors associated with implant failure in patients who had undergone immediate implant restoration. We performed a retrospective review and an outcome assessment of all patients who received immediate implant restoration between 2000 and 2010 in our department at Tokushima University Hospital. The patients were divided into groups on the basis of the predictor variables: age, gender, implant location, and number of implants per jaw. The cumulative implant survival rate in the paired groups was determined by using Kaplan-Meier analysis and the log-rank test. Cox proportional hazards model was subsequently used to identify exposures associated with implant failure. Using the Kaplan-Meier method, the survival rates at 1, 3, and 9 years were calculated to be 98.8%, 98.0%, and 94.7%, respectively. No statistically significant association was observed between the implant survival rates and the predictor variables: gender, age, location, and number of implants. Immediate implant restoration is a reliable prosthetic procedure with an acceptable survival rate compared to the conventional implant procedure.
Tetsuo Ichikawa, Osamu Ishida, Megumi Watanabe, Yoritoki Tomotake and Hua Wei : A new retrieval system for cement-retained implant superstructures., Journal of Prosthodontics, Vol.17, No.6, 487-489, 2008.
(要約)
This article discusses two methods for improving the retrievability of cement-retained implant superstructures. One method involves incorporating a removal screw in the superstructure and the second method uses a small dimple on the abutment, accessed through a vent in the superstructure.
Naozumi Ishimaru, Rieko Arakaki, Megumi Watanabe, Kobayashi Masaru, Katsushi Miyazaki and Yoshio Hayashi : Development of autoimmune exocrinopathy resembling Sjogren's syndorome in estorogen deficient mice of healthy background, The American Journal of Pathology, Vol.163, No.4, 1481-1490, 2003.
(要約)
Although a number of autoimmune diseases are known to develop in postmenopausal women, the mechanisms by which estrogen deficiency influences autoimmune lesions remain unclear. We speculate that antiestrogenic actions might be a potent factor in the formation of pathogenic autoantigens. Previously, we have identified 120-kd alpha-fodrin as an important autoantigen in Sjögren's syndrome (SS). When healthy C57BL/6 (B6) mice were treated with an ovariectomy (Ovx), we found a significant increase in TUNEL(+)-apoptotic epithelial cells in the salivary gland cells associated with alpha-fodrin cleavage during 2 and 3 weeks after Ovx. By contrast, no apoptotic cells were found in estrogen receptor-alpha knockout mice. In in vitro studies using primary cultured mouse salivary gland cells and human salivary gland cells, we found a cleavage product of 120-kd alpha-fodrin in cells that had undergone tamoxifen (Tam)-induced apoptosis through caspase activation, especially caspase-1. Adoptive transfer of alpha-fodrin-reactive T cells into Ovx-B6 and -SCID mice resulted in the development of autoimmune exocrinopathy quite similar to SS. These results suggest that estrogen deficiency exerts a crucial influence on autoantigen cleavage, and may cause, in part, autoimmune exocrinopathy in postmenopausal women.
Lipei Liu, Megumi Watanabe and Tetsuo Ichikawa : Robotics in Dentistry: A Narrative Review, Dentistry Journal, Vol.11, No.3, 62, 2023.
(要約)
Robotics is progressing rapidly. The aim of this study was to provide a comprehensive overview of the basic and applied research status of robotics in dentistry and discusses its development and application prospects in several major professional fields of dentistry. A literature search was conducted on databases: MEDLINE, IEEE and Cochrane Library, using MeSH terms: ["robotics" and "dentistry"]. Forty-nine articles were eventually selected according to certain inclusion criteria. There were 12 studies on prosthodontics, reaching 24%; 11 studies were on dental implantology, accounting for 23%. Scholars from China published the most articles, followed by Japan and the United States. The number of articles published between 2011 and 2015 was the largest. With the advancement of science and technology, the applications of robots in dental medicine has promoted the development of intelligent, precise, and minimally invasive dental treatments. Currently, robots are used in basic and applied research in various specialized fields of dentistry. Automatic tooth-crown-preparation robots, tooth-arrangement robots, drilling robots, and orthodontic archwire-bending robots that meet clinical requirements have been developed. We believe that in the near future, robots will change the existing dental treatment model and guide new directions for further development.
後藤 崇晴, 岩脇 有軌, 渡邉 恵, 永尾 寛, 市川 哲雄 : 補綴装置による個人認証システムに関する文献的考察, Journal of Oral Health and Biosciences, Vol.27, No.2, 21-27, 2015年2月.
(要約)
In disasters such as hydraulic bore, earthquakes and fire, the oral structure including the dental prostheses can provide identifying information. Over the years, many different personal identification system of dental prostheses have been reported. This present study analyzes the published literature offering the description of the personal identification system of dental prostheses.Two databases, "PubMed" and "Japana Centra Revuo Medicina" were searched to retrieve research papers referred to the personal identification system of dental prostheses. Twenty four papers were selected from the database with the criteria, and they were reviewed. This literature search showed that the personal identifications in three kinds of dental prostheses: removable denture, crown and implant were reported; and more papers on removable dentures were extracted compared to the crown and implant, however there is no high quality paper indicating that the structured methods for personal identification of dental prostheses is effective. A new method and common write format for personal identification are required to improve the present problems, and our systems using fluorescent material and ultraviolet light and femtosecond pulse laser-oriented recording system would be effective.
Megumi Watanabe : Biological reaction to magnetic fields., SYMPOSIUM OF DIGITAL & MAGNET DENTISTRY, Oct. 2023.
2.
Mohammad Fadyl Yunizar, Megumi Watanabe, Lipei Liu and Tetsuo Ichikawa : The pathogenesis of oral lichen planus related to metal reaction, International College of Prosthodontics, 19th Biennial Meeting, Sep. 2021.
3.
Mohammad Fadyl Yunizar, Megumi Watanabe, Lipei Liu and Tetsuo Ichikawa : The Pathogenesis of Oral Lichen Planus Related to Metal Allergy Reaction, International College of Prosthodontics, 19th Biennial Meeting, Vol.0, No.0, 00, virtual meeting, Sep. 2021.
4.
Lipei Liu, Megumi Watanabe, Mohammad Fadyl Yunizar and Tetsuo Ichikawa : Semaphorin3A Promotes the Development of Nickel Allergy, International College of Prosthodontics, 19th Biennial Meeting, virtual meeting, Sep. 2021.
5.
Megumi Watanabe and Tetsuo Ichikawa : The effect of ELF pulsed magnetic fields on osteoblast differentiation via MAP kinase pathways, International College of Prosthodontists, Sep. 2017.
6.
Megumi Watanabe and Tetsuo Ichikawa : Magnetic Fields Enhanced Osteoblast Differentiation via ERK Pathways, 16th International College of Prosthodontics Biennial Meeting, Seoul, Sep. 2015.
7.
Megumi Watanabe and Tetsuo Ichikawa : Extremely Low Frequency Pulsed Magnetic Fields Accelerate Osteoblast Differentiation, 3rd ASEAN plus and TOKUSHIMA Joint International Conference, Makassar, Dec. 2014.
8.
Takaharu Goto, Yuichi Ishida, Megumi Watanabe, Yoritoki Tomotake, Kan Nagao and Tetsuo Ichikawa : Location of the main occluding area after implant treatment, 38th Annual Conference of The European Prosthodontic Association, Istanbul, Sep. 2014.
9.
Megumi Watanabe and Tetsuo Ichikawa : Analysis of Small GTPases in Keratinocytes during Nickel Allergy Development, 38th Annual Conference of The European Prosthodontic Association, Istanbul, Sep. 2014.
10.
Megumi Watanabe : Dental implant failure; related factors and clinical cases, Surabayai, Nov. 2013.
11.
Megumi Watanabe : The Role of MKK6/p38 Signal Cascade in Dendritic Cells in Nickel Allergy Mouse Model, Kalimantan Symposia, Balikpapan, Dec. 2011.
12.
Megumi Watanabe and Tetsuo Ichikawa : Extremely Low Frequency Pulsed Magnetic Fields Accelerate Osteoblast Differentiation, International College of Prosthodontics, Sep. 2011.
13.
Ashrin Nur Meinar, Naozumi Ishimaru, Megumi Watanabe, Yoshio Hayashi and Tetsuo Ichikawa : Analysis of Molecular Mechanism for Pathogenesis of Metal Allergy, International Joint Symposium, The University of Tokushima-Niigata University-Gajah Mada University, Bali, Dec. 2010.
14.
Takanori Kawano, Tetsuo Ichikawa, Yoshihito Naitou, Megumi Watanabe and Takaharu Goto : Surface Modification of Titanium by Blue-violet Semiconductor Laser and Ultraviolet Light Emitting Diode, 19th Annual Scientific Meeting European Assocoation for Osseintegration, Glasgow, Oct. 2010.
15.
Megumi Watanabe and Tetsuo Ichikawa : Extremely low frequency pulsed magnetic fields accelerate osteoblast differentiation, 19th Annual Scientific Meeting European Assocoation for Osseintegration, Glasgow, Oct. 2010.
16.
Yoshihito Naitou, Kenichi Hamada, Takaharu Goto, Megumi Watanabe, Daisuke Nagao, Yoritoki Tomotake and Tetsuo Ichikawa : Powder-size effect on biocompatibility of porous-titanium produced using moldless-process, 19th Annual Scientific Meeting European Assocoation for Osseintegration, Glasgow, Oct. 2010.
17.
Takaharu Goto, Kan Nagao, Yuichi Ishida, Yoshihito Naitou, Megumi Watanabe, Yoritoki Tomotake and Tetsuo Ichikawa : Influence of Attachments on Load Transfer in Implant Overdentures, 19th Annual Scientific Meeting European Assocoation for Osseintegration, Glasgow, Oct. 2010.
18.
Daisuke Nagao, Katsuhiko Yoshimoto, Yoritoki Tomotake, Megumi Watanabe, Y Yoshijima and Tetsuo Ichikawa : Gene expression in a mouse osteoblast like cell line in response to compressing force., 11th International College of Prosthodontists, Crete, Greece, May 2005.
Lipei Liu, Megumi Watanabe, Mohammad Fadyl Yunizar and Tetsuo Ichikawa : Semaphorin3A: A novel potential target for prevention and treatment of nickel allergy, 第50回日本免疫学会学術集会, Dec. 2021.
8.
Liu Lipei, 渡邉 恵, 南 憲一, MOHAMMAD FADYL YUNIZAR, 市川 哲雄 : 金属アレルギー発症過程におけるセマフォリン 3A の役割, (公社)日本補綴歯科学会第130回記念学術大会, 2021年6月.
Nur Meinar Ashrin, Megumi Watanabe, Rieko Arakaki, Akiko Yamada, Tetsuo Ichikawa, Yoshio Hayashi and Naozumi Ishimaru : Analysis of Immune Responess to Metal using Murine Nickel Allergy Model., Proceedings of the Japanese Society for Immunology, Vol.40, 102, Nov. 2011.
Ashrin Nur Meinar, Megumi Watanabe and Tetsuo Ichikawa : Analysis of Molecular Mechanism for Pathogenesis of Nickel Allergy, 社団法人日本補綴歯科学会 第120回記念学術大会, May 2011.
李 景, Yoshihito Naitou, Megumi Watanabe, Daisuke Nagao and Tetsuo Ichikawa : Characteristics of Candidal adherence and biofilm formation on materials used in the implant overdenture, 第40回日本口腔インプラント学会・学術大会, Sep. 2010.