The Bulletin of Tokyo Dental College
Print ISSN : 0040-8891
Volume 60, Issue 4
Displaying 1-9 of 9 articles from this issue
Original Articles
  • Mai Ohkubo, Takayuki Ueda, Keina Miura, Hiroki Sugito, Keisuke Ono, Fu ...
    2019 Volume 60 Issue 4 Pages 225-232
    Published: 2019
    Released on J-STAGE: December 10, 2019
    Advance online publication: November 22, 2019
    JOURNAL FREE ACCESS

    Patients often experience temporary difficulty in masticating during the period immediately following dental treatment. The purpose of this study was to investigate subjectively assessed satisfaction with a specially designed diet for such patients by means of a questionnaire. These “easy-to-eat meals” were planned and provided by this hospital in Japan, and comprised a combination of commercially available and nutritionally rich soft foods, jellied foods, drinks, and other items. The patients were required to commence consuming them immediately following dental treatment. The questionnaire contained 6 categories —Satisfaction, Taste, Meal completion, Convenience, Reduction in discomfort, and Likelihood of reuse — to be evaluated on a 10-cm visual analog scale (VAS). The overall response was positive in all 41 completed questionnaires, with an overall score of 6 or higher for every category. Orthodontics achieved the highest VAS score in every category, followed by oral implantology, prosthodontics, and conservative Original Article doi:10.2209/tdcpublication.2018-0055 dentistry. A correlation was observed between Satisfaction and each of the 5 remaining questionnaire categories (Taste: |r|=0.70, p≤0.00; Meal completion: |r|=0.60, p≤0.00; Convenience: |r|=0.56, p≤0.00; Reduction in discomfort: |r|=0.48, p=0.00; and Likelihood of reuse: |r|=0.79, p≤0.00). An acceptable level of convenience was obtained with these meals, as they were reported to be useful during the period immediately following treatment, when eating out or preparing meals was physically and/or psychologically difficult.

    Download PDF (135K)
  • Nobuyuki Horie, Takehito Ouchi, Rumiko Nishiyama, Sho Usuda, Satoru Mo ...
    2019 Volume 60 Issue 4 Pages 233-239
    Published: 2019
    Released on J-STAGE: December 10, 2019
    Advance online publication: November 23, 2019
    JOURNAL FREE ACCESS

    The need for flexible thermoplastic denture base materials has increased due to patient demand for better esthetic outcomes. Designs aimed at improving esthetic outcomes can cause difficulties for prosthodontists, however, from the viewpoint of function and maintenance. Therefore, the purpose of this study was to investigate vertical displacement in unilateral extension base denture models, comparing that obtained by flexible removable dentures with that by conventional metal clasp dentures. Models of unilateral extension base flexible removable dentures for mandibular defects were prepared. Periodontal ligament and jaw mucosa were simulated using a silicone impression material. Four types of flexible removable denture, with or without a metal rest, and two metal clasp dentures made of acrylic resin as a conventional design were used as dental prostheses. The amount of vertical displacement in the defect areas was measured under a load of 50 N at the first and second molars. Among the 6 types of dentures investigated, the amount of vertical displacement was greater with flexible removable dentures than with metal clasp dentures. This vertical displacement tended to decrease significantly, however, with the use of a metal rest with the flexible removable dentures. Esteshot with a metal rest, in particular, showed the smallest amount of displacement in the flexible removable dentures (first molar, 0.265±0.007 mm; second molar, 0.423±0.008 mm). These results indicate the importance of the application of rests in unilateral extension base flexible removable dentures. It may be useful to employ a metal rest in conjunction with a flexible removable denture to reduce load on the underlying mucosa, as is done with conventional partial dentures.

    Download PDF (315K)
  • Haruyo Miyazaki, Etsuko Motegi, Kenji Sueishi
    2019 Volume 60 Issue 4 Pages 241-250
    Published: 2019
    Released on J-STAGE: December 10, 2019
    Advance online publication: November 22, 2019
    JOURNAL FREE ACCESS

    The postgraduate training course at the Department of Orthodontics of Tokyo Dental College, which started in April 1975, comprises a 3-year curriculum aimed at fostering orthodontic specialists. A system of Accreditation for Orthodontists was introduced by the Japan Orthodontic Society in 1990, since which time, this postgraduate training course has also sought to provide the basic training required to obtain such certification. The purpose of this study was to investigate the demographics of the students on this course and the current work status of its graduates by means of a questionnaire-based survey. The results revealed that, when the fortieth intake of students graduated in March 2017, the total number completing the course had reached 326. The annual mean number of students on this course was 8.2, and recent years have seen a marked increase in the number of women enrolling. In total, 37.5% of the questionnaire respondents had opened orthodontic clinics; 14.8% had opened general dentistry clinics; and 42.6% were working as employees. In addition, 46.2% had an additional place of employment other than their principal place of employment, mainly at a general dentistry clinic. Regarding the field of treatment, 82.4% provided solely orthodontic treatment. We believe that this may because all the responders had completed the postgraduate orthodontics course. The rate of earning accreditation as an orthodontist was high (82.4%), with no difference in the rate of acquisition between men and women. The rate of qualification as a Board-certified orthodontist was 17.9%, with the rate of acquisition by women approximately half of that by men. The number of female orthodontists is rising, and no difference was observed between sexes in the rate of acquiring accreditation as an orthodontist. Women were found to be lagging behind men, however, in regard to the rate of advancement to masters/PHD programs; qualifying as a Board-certified orthodontist; opening an orthodontic practice; and number of days worked. These findings suggest that there are differences in regard to the actual working conditions among the alumni of our postgraduate orthodontic training course, and that these differences are sex-based.

    Download PDF (300K)
  • Shoichi Sekikawa, Ayako Kozakai, Hirokazu Saito, Homare Kawachi, Sator ...
    2019 Volume 60 Issue 4 Pages 251-260
    Published: 2019
    Released on J-STAGE: December 10, 2019
    Advance online publication: November 22, 2019
    JOURNAL FREE ACCESS

    The facilities comprising Tokyo Dental College (TDC) —the college itself and its medical institutions at Suidobashi, Ichikawa, and Chiba — have been officially recognized as a center for treating oral cancer. The TDC Oral Cancer Center (OCC) was established on April 1, 2006. It provides comprehensive medical care, including that aimed at recovery of postoperative function, such as restoration of stomatognathic function, dysphagia therapy, and placement of maxillary prostheses. The purpose of this study was to investigate patient trends at TDC-OCC over the 10 years following its establishment in order to determine how the safe and high-quality cancer care already provided might be even further improved. Oral cancer patients attending TDC-OCC between April 2007 and March 2017 were investigated. Clinical information was obtained from medical records and analyzed, including that on patient numbers, age, sex, primary site of tumor, clinical stage, and surgery provided. There were 758 new cases, and the number of new cases showed an annual increase. Among the total number of new patients, 575 (75.9%) represented primary cases. The number of operations also showed an increase, which correlated with the increase in the number of patients. The incidence in oral cancer has increased in several countries, including Japan. Oral cancer can be observed macroscopically and touched. In contrast to with cancers at many other sites, and despite various diagnostic devices for early detection having been developed, however, cases are often advanced when first encountered. Many advanced cases were treated at TDC-OCC, and the number of reconstructive operations following progressive cancer also increased over time.

    Download PDF (364K)
  • Yoichi Ishizuka, Mizuki Yoshida, Kimiharu Ambe, Junzo Sasaki, Naoki Su ...
    2019 Volume 60 Issue 4 Pages 261-266
    Published: 2019
    Released on J-STAGE: December 10, 2019
    Advance online publication: November 23, 2019
    JOURNAL FREE ACCESS

    Active oxygen and free radicals are involved in metabolism in cells and tissues. Immunohistological studies of related enzymes are few, and the morphological dynamics of these enzymes in dental pulp and odontoblasts remain to be elucidated. Nitric oxide synthase (NOS) has 3 isoforms: nNOS, iNOS, and eNOS. The aim of this study was to investigate the profiles of NOS isoforms in the absence of nNOS in dental pulp and odontoblasts. Five-week-old male C57BL/6 and nNOS knockout (KO) mice were sacrificed and expression of nNOS, iNOS, and eNOS determined immunohistochemically. Expression of nNOS was positive, whereas that of iNOS was negative and eNOS weakly positive in the dental pulp and odontoblasts of the control mice. In nNOS KO mice, expression of iNOS was positive in dental pulp and strongly positive in odontoblasts, whereas that of eNOS was stronger in fibroblasts, endothelial cells in the vicinity of blood vessels in the dental pulp, and odontoblasts. Expression of nNOS was negative in the nNOS KO mice. This suggests that iNOS and eNOS compensate for nNOS deficiency in vascular endothelial cells and fibroblasts in the dental pulp and odontoblasts.

    Download PDF (650K)
  • Ayano Nakauchi, Seikou Shintani, Eitoyo Kokubu, Kei Nakajima, Kenichi ...
    2019 Volume 60 Issue 4 Pages 267-277
    Published: 2019
    Released on J-STAGE: December 10, 2019
    Advance online publication: November 22, 2019
    JOURNAL FREE ACCESS

    The purpose of this study was to investigate the behavior of epithelial lining derived from Malassez's epithelial rest (MER) cells in experimentally created inflammatory cysts in vivo and in vitro. Porcine MER cells were cultured in vitro with or without interleukin (IL)-1β (1 ng/ml) or IL-6 (1 ng/ml). Cell proliferation was assessed and expression levels of CK19 and CK13 mRNA determined using RT-PCR. In vivo, a cavity was created in the first molar of Sprague-Dawley male rats and tissue repair observed using immunohistochemical methods. In vitro, treatment with IL-1β or IL-6 increased proliferation of MER cells and decreased expression of CK19 mRNA, but increased CK13 mRNA at day 1 (p<0.05). In vivo, at 2 weeks, CK19-positive epithelial cells were observed adjacent to the cementum, in the cystic lesion, and in connective tissue. At 3 weeks, they were only detected in cells adjacent to the connective tissue. Cells positive for CK13 were observed throughout the epithelium, except in cells adjacent to connective tissue at weeks 2 and 3. Exposure to IL-1β and/or IL-6 induced proliferation and differentiation of MER cells.

    Download PDF (885K)
  • Sujatha Pai B, AR Pradeep
    2019 Volume 60 Issue 4 Pages 279-289
    Published: 2019
    Released on J-STAGE: December 10, 2019
    Advance online publication: November 22, 2019
    JOURNAL FREE ACCESS

    Interleukin (IL)-33 is a dual-function protein that may play important roles as both a cytokine and intracellular nuclear factor. It may also function similarly to prototypical alarmin IL-1α, as an endogenous danger signal to alert innate immune system cells to tissue damage during trauma or infection, as it can be released in the extracellular space after endothelial cell damage or mechanical injury. The aim of this study was to determine possible correlations between concentrations of IL-33 and IL-1α in gingival crevicular fluid (GCF) and plasma obtained from healthy patients, those with chronic periodontitis (CP), and those with generalized aggressive periodontitis (GAP) patients. Forty-five patients with an age range of 20–60 years were enrolled and divided into 3 groups: Group H, 30 samples (15 GCF and 15 plasma) from 15 patients with healthy periodontium; Group CP, 30 samples from 15 patients with CP; and Group GAP, 30 samples from 15 patients with GAP. The clinical periodontal parameters investigated in all groups comprised the gingival index score, probing pocket depth, and clinical attachment level. The GCF and plasma levels of IL-33 and IL-1α were quantitated using enzyme linked immunosorbent assay. The mean IL-33 concentrations in GCF and plasma were highest in Group GAP, followed by Group CP, with the lowest in Group H; the difference among them was statistically significant (p<0.05). Concentration of IL-1α followed the same trend as that of IL-33 in GCF, but was lower than detection levels in plasma. The GCF and plasma concentrations of IL-33 correlated with IL-1α concentrations in GCF. Concentrations of IL-33 and IL-1α in GCF varied significantly between healthy patients and those with disease, allowing healthy patients to be distinguished from those with GAP or CP. The results of this study suggest that IL-33 offers a potential inflammatory marker of periodontal disease, similar to IL-1α.

    Download PDF (173K)
Case Report
  • Akira Watanabe, Shuji Yoshida, Takenobu Ishii, Chikara Saito, Takahiko ...
    2019 Volume 60 Issue 4 Pages 291-296
    Published: 2019
    Released on J-STAGE: December 10, 2019
    Advance online publication: November 22, 2019
    JOURNAL FREE ACCESS

    Median clefts, which run through the midline of the upper lip, and alveolus are considered a type of craniofacial cleft. A Tessier number 0 median cleft lip is the rarest, and there are few reports concerning its surgical management. Here, we describe the case of a 6-year-old boy who presented at our hospital with a median cleft and alveolus of the upper lip with a shortened bifid frenulum. Inverted-V and Z-plasty incisions were performed for the median cleft and iliac bone grafting for the midline alveolus. At 1 year 5 months later, the postoperative course was uneventful, and proper approximation of the orbicularis oris muscle and vermilion were achieved, with a symmetrical Cupid's bow and labial tubercle and philtrum.

    Download PDF (501K)
Dental Education
  • Naoko Takahashi, Hitoshi Yamamoto, SoIchiro Hirata, Naoki Sugihara, Ri ...
    2019 Volume 60 Issue 4 Pages 297-302
    Published: 2019
    Released on J-STAGE: December 10, 2019
    Advance online publication: November 22, 2019
    JOURNAL FREE ACCESS

    The purpose of this study was to investigate the effectiveness of the Communication Studies Program at Tokyo Dental College as a tool in behavioral education. The number of Patient Community members who had participated in multiple sets of the program for third-year students in the same year within the 3-year period spanning 2016 to 2018 (152, 148, and 129 students in 2016, 2017, and 2018 respectively), and the period during which they had participated in multiple sets were investigated. Comments on student behavior, including on hairstyle, clothes, and attitude, were also analyzed. The total number of members who had participated in multiple sets (1 set comprised 1 lecture and 2 training sessions) was 5; and their comments were more favorable during the second (sets 3 and 4) than the first half of the 1-month program (sets 1 and 2). During the first half, the students were criticized for speaking softly, having bad posture, not concentrating, and having an attitude inappropriate for a medical worker; but in the second half, they were praised for beginning to adopt the proper attitude for a medical worker, speaking louder, having better posture, and a very serious attitude. These findings suggest that the Communication Studies Program is effective in improving student behavior.

    Download PDF (71K)
feedback
Top