• 제목/요약/키워드: dental research

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Head and neck radiotherapy-induced changes in dentomaxillofacial structures detected on panoramic radiographs: A systematic review

  • Munhoz, Luciana;Nishimura, Danielle Ayumi;Iida, Christyan Hiroshi;Watanabe, Plauto Christopher Aranha;Arita, Emiko Saito
    • Imaging Science in Dentistry
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    • v.51 no.3
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    • pp.223-235
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    • 2021
  • Purpose: This study aimed to summarize the impact of neck and head radiation treatment on maxillofacial structures detected on panoramic radiographs. Materials and Methods: In this systematic review, the authors searched PubMed Central, Embase, Scopus, Cochrane Central Register of Controlled Trials, Web of Science, and Google Scholar for original research studies up to February 2020 that included the following Medical Subject Headings keywords: words related to "radiotherapy" and synonyms combined with keywords related to "panoramic radiography" and "oral diagnosis" and synonyms. Only original studies in English that investigated the maxillofacial effects of radiotherapy via panoramic radiographs were included. The quality of the selected manuscripts was evaluated by assessing the risk of bias using Cochrane's ROBINS-I tool for non-randomized studies. Results: Thirty-three studies were eligible and included in this review. The main objectives pertained to the assessment of the effects of radiation on maxillofacial structures, including bone architecture alterations, periodontal space widening, teeth development abnormalities, osteoradionecrosis, and implant bone loss. The number of participants evaluated ranged from 8 to 176. Conclusion: The interaction between ionizing radiation and maxillofacial structures results in hazard to the tissues involved, particularly the bone tissue, periosteum, connective tissue of the mucosa, and endothelium. Hard tissue changes due to radiation therapy can be detected on panoramic radiographs.

Chitosan/hydroxyapatite composite coatings on porous Ti6Al4V titanium implants: in vitro and in vivo studies

  • Zhang, Ting;Zhang, Xinwei;Mao, Mengyun;Li, Jiayi;Wei, Ting;Sun, Huiqiang
    • Journal of Periodontal and Implant Science
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    • v.50 no.6
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    • pp.392-405
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    • 2020
  • Purpose: Titanium implants are widely used in the treatment of dentition defects; however, due to problems such as osseointegration failure, peri-implant bone resorption, and periimplant inflammation, their application is subject to certain restrictions. The surface modification of titanium implants can improve the implant success rate and meet the needs of clinical applications. The goal of this study was to evaluate the effect of the use of porous titanium with a chitosan/hydroxyapatite coating on osseointegration. Methods: Titanium implants with a dense core and a porous outer structure were prepared using a computer-aided design model and selective laser sintering technology, with a fabricated chitosan/hydroxyapatite composite coating on their surfaces. In vivo and in vitro experiments were used to assess osteogenesis. Results: The quasi-elastic gradient and compressive strength of porous titanium implants were observed to decrease as the porosity increased. The in vitro experiments demonstrated that, the porous titanium implants had no biological toxicity; additionally, the porous structure was shown to be superior to dense titanium with regard to facilitating the adhesion and proliferation of osteoblast-like MC3T3-E1 cells. The in vivo experimental results also showed that the porous structure was beneficial, as bone tissue could grow into the pores, thereby exhibiting good osseointegration. Conclusions: Porous titanium with a chitosan/hydroxyapatite coating promoted MC3T3-E1 cell proliferation and differentiation, and also improved osseointegration in vitro. This study has meaningful implications for research into ways of improving the surface structures of implants and promoting implant osseointegration.

Differential Expression Profiling of Salivary Exosomal microRNAs in a Single Case of Periodontitis - A Pilot Study

  • Park, Sung Nam;Son, Young Woo;Choi, Eun Joo;You, Hyung-Keun;Kim, Min Seuk
    • International Journal of Oral Biology
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    • v.43 no.4
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    • pp.223-230
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    • 2018
  • Exosomes are Nano-sized lipid vesicles secreted from mammalian cells containing diverse cellular materials such as proteins, lipids, and nucleotides. Multiple lines of evidence indicate that in saliva, exosomes and their contents such as microRNAs (miRNAs) mediate numerous cellular responses upon delivery to recipient cells. The objective of this study was to characterize the different expression profile of exosomal miRNAs in saliva samples, periodically isolated from a single periodontitis patient. Unstimulated saliva was collected from a single patient over time periods for managing periodontitis. MicroRNAs extracted from each phase were investigated for the expression of exosomal miRNAs. Salivary exosomal miRNAs were analyzed using Affymetrix miRNA arrays and prediction of target genes and pathways for its different expression performed using DIANA-mirPath, a web-based, computational tool. Following the delivery of miRNA mimics (hsa-miR-4487, -4532, and -7108-5p) into human gingival fibroblasts, the expression of pro-inflammatory cytokines and activation of the MAPK pathway were evaluated through RT-PCR and western blotting. In each phase, 13 and 43 miRNAs were found to be differently expressed $({\mid}FC{\mid}{\geq}2)$. Among these, hsa-miR-4487 $({\mid}FC{\mid}=9.292005)$ and has-miR-4532 $({\mid}FC{\mid}=18.322697)$ were highly up-regulated in the clinically severe phase, whereas hsa-miR-7108-5p $({\mid}FC{\mid}=12.20601)$ was strongly up-regulated in the clinically mild phase. In addition, the overexpression of miRNA mimics in human gingival fibroblasts resulted in a significant induction of IL-6 mRNA expression and p38 phosphorylation. The findings of this study established alterations in salivary exosomal miRNAs which are dependent on the severity of periodontitis and may act as potential candidates for the treatment of oral inflammatory diseases.

Feasibility of clay-shielding material for low-energy photons (Gamma/X)

  • Tajudin, S.M.;Sabri, A.H.A.;Abdul Aziz, M.Z.;Olukotun, S.F.;Ojo, B.M.;Fasasi, M.K.
    • Nuclear Engineering and Technology
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    • v.51 no.6
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    • pp.1633-1637
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    • 2019
  • While considering the photon attenuation coefficient (${\mu}$) and its related parameters for photons shielding, it is necessary to account for its transmitted and reflected photons energy spectra and dose contribution. Monte Carlo simulation was used to study the efficiency of clay ($1.99g\;cm^{-3}$) as a shielding material below 150 keV photon. Am-241 gamma source and an X-ray of 150 kVp were calculated. The calculated value of ${\mu}$ for Am-241 is higher within 5.61% compared to theoretical value for a single-energy photon. The calculated half-value layer (HVL) is 0.9335 cm, which is lower than that of ordinary concrete for X-ray of 150 kVp. A thickness of 2 cm clay was adequate to attenuate 90% and 85% of the incident photons from Am-241 and X-ray of 150 kVp, respectively. The same thickness of 2 cm could shield the gamma source dose rate of Am-241 (1 MBq) down to $0.0528{\mu}Sv/hr$. For X-ray of 150 kVp, photons below 60 keV were significantly decreased with 2 cm clay and a dose rate reduction by ~80%. The contribution of reflected photons and dose from the clay is negligible for both sources.

The Effects of Drinking Motivation on female college student Perceptions and Behaviors of Drinking. (여대생의 음주 동기가 음주에 관한 인식과 행동에 미치는 영향)

  • Son, Eun-Gyo;Jung, Hwa-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.12
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    • pp.161-169
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    • 2018
  • The purpose of this study was to investigate the effect of alcohol drinking motivation on the drinking behaviors of female college students. It is necessary to examine the drinking behavior of female college students not only for their academic performance and health status but also for future reproduction concerns. The subjects of this study included 296 college students in their 20s. Research data was analyzed using SPSS 24.0 and AMOS 22 statistical programs. Results of this study found academic and human relationships had the greatest effect on the stress level of female college students. In addition, the perception of drinking was more influential on the drinking problem, and female college students who perceived anxiety through the drinking problem tried to change the behavior of drinking. Also, the perception of drinking by the influence of alcohol was more significant than that of drinking by college students who perceived anxiety through drinking problem. Second, if drinking is beneficial in the internal or external motivation of the individual, it maintains drinking behaviors and changes the behavior of drinking when experiencing the problem of drinking. Through these results, we aim to contribute to the reduction of the negative risk of alcohol by understanding the drinking preference of female college students and examining the drinking culture according to drinking motives.

Determination of the optimal diabetes duration for bone regeneration experiments in an alloxan-induced diabetic rabbit calvarial defect model

  • Jeong, Sang-Hun;Jung, Bo Hyun;Yoo, Ki-Yeon;Um, Heung-Sik;Chang, Beom-Seok;Lee, Jae-Kwan;Choi, Won-Youl
    • Journal of Periodontal and Implant Science
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    • v.48 no.6
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    • pp.383-394
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    • 2018
  • Purpose: The purpose of this study was to evaluate the optimal diabetes duration for bone regeneration experiments in an alloxan monohydrate (ALX)-induced diabetic rabbit calvarial defect model by evaluating the association between diabetes duration and bone healing capacity. Methods: Twenty-four New Zealand white rabbits were used. Twenty-two rabbits were injected with 100 mg/kg of ALX to induce experimental diabetes. These rabbits were divided into 4 groups, including a control group and groups with diabetes durations of 1 week (group 1), 2 weeks (group 2), and 4 weeks (group 3). Calvarial defects were created at 1, 2, and 4 weeks after ALX injection and in the control rabbits. Cone-beam computed tomography (CBCT) scanning was performed on the day of surgery and at 2 and 4 weeks after surgery. The rabbits were sacrificed 4 weeks after surgery, followed by histological and immunofluorescence analysis. Results: The diabetic state of all diabetic rabbits was well-maintained throughout the experiment. Reconstructed 3-dimensional CBCT imaging showed more rapid and prominent bone regeneration in the control group than in the experimental groups. Histological staining showed notable bone regeneration in the control group, in contrast to scarce bone formation in the experimental groups. The appearance and immunoreactivity of receptor activator of nuclear factor-kappa B and osteoprotegerin did not show notable differences among the groups. Conclusion: ALX administration at 100 mg/kg successfully induced experimental diabetes in rabbits. The effect of diabetes on bone healing was evident when the interval between diabetes induction and the intervention was ${\geq}1$ week.

Factors Affecting Herpes Zoster Vaccination in Adults (성인의 대상포진 예방접종 시행의 영향 요인)

  • Jeong, Sun Rak;Kim, Yu Mi;Kim, Kyung Hee;Nam, Hang Me;Lee, Won Kee
    • The Korean Journal of Health Service Management
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    • v.12 no.2
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    • pp.63-73
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    • 2018
  • Objectives : This study aimed investigate general characteristics, vaccination status and health beliefs related to vaccination for herpes zoster and to identify variables. Methods : The structured questionnaire was conducted from March 31, 2016 to April 20, 2016 with 312 outpatients who visited a university hospital. The data were analyzed by frequency analysis, t-test, $x^2-test$, correlation analysis and logistic regression analysis via SPSS statistics 22.0. Results : The vaccination rate of the herpes zoster was 16.0% and the vaccination cost was the most common reason for rejecting inoculation. More highly educated people with more than a university degree(OR=4.28, p=.002), those with higher susceptibility to herpes zoster(OR=1.56, p=.000), those more aware of the benefits of vaccination(OR=1.51, p=.009) and those with lower disability for vaccination(OR=0.74, p=.003) were more likely to be vaccinated. Conclusions : Therefore, to increase the vaccination rate of herpes zoster in adults over 50 years old, continuous publicity and education are needed to emphasize the susceptibility of herpes zoster and the benefit of vaccination. In addition, it is necessary to develop policies at the national level for the expensive vaccination cost that obstructs vaccination.

The Relation Between Parenting Attitudes and Child's Oral Health Behavior (부모의 양육태도와 아동의 구강보건 행동의 관련성)

  • Noh, Eun-Mi
    • Journal of Convergence for Information Technology
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    • v.10 no.12
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    • pp.140-145
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    • 2020
  • This study was conducted to check the effect of parenting attitudes on oral health behavior on lower grade elementary school students where oral care habits are formed. The subjects of the study were 366 students in the lower grades of elementary school, and the research tools used self-written questionnaires that were modified and supplemented to suit this purpose. Parenting attitudes of parents and lower-grade oral health behavior of elementary school students showed significant amounts of correlation, especially affectionate, autonomous and reasonable parenting attitudes were highly correlated with oral health behaviors(p<0.01). A multiple regression analysis to identify the factors affecting oral health behavior showed that parental attitudes also had a significant effect on the child variables(p<0.01). Therefore, since parenting attitudes are related to children's oral health behaviors, it is believed that measures should be taken to promote oral health education that can be improved by combining them.

A study of bone regeneration effect according to the two different graft bone materials in the cranial defects of rabbits

  • Song, Hyun-Jong;Kim, Hyun-Woo;Min, Gwi-Hyeon;Lee, Won-Pyo;Yu, Sang-Joun;Kim, Byung-Ock
    • Oral Biology Research
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    • v.42 no.4
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    • pp.198-207
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    • 2018
  • Guided tissue regeneration (GBR) has been used to promote new bone formation in alveolar bone reconstruction at defective bone sites following tooth loss. Bone grafts used in GBR can be categorized into autogenous, xenogenous, and synthetic bones, and human allografts depending on the origin. The purpose of this study was to compare the rates of bone regeneration using two different bone grafts in the cranial defects of rabbits. Ten New Zealand rabbits were used in this study. Four defects were created in each surgical site. Each defect was filled as follows: with nothing, using a 50% xenograft and 50% human freeze-dried bone allograft (FDBA) depending on the volume rate, human FDBA alone, and xenograft alone. After 4 to 8 weeks of healing, histological and histomorphometric analyses were carried out. At 4 weeks, new bone formation occurred as follows: 18.3% in the control group, 6.5% in group I, 8.8% in group II, and 4.2% in group III. At 8 weeks, the new bone formation was 14.9% in the control group, 36.7% in group I, 39.2% in group II, and 16.8% in group III. The results of this study suggest that the higher the proportion of human FDBA in GBR, the greater was the amount of clinically useful new bone generated. The results confirm the need for adequate healing period to ensure successful GBR with bone grafting.

A Study on Research Trends and Development Process of Health Policy for the Elderly (노인보건정책의 발전과정 및 연구동향에 대한 일고찰)

  • Sunwoo, Duk
    • 한국노년학
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    • v.28 no.4
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    • pp.773-784
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    • 2008
  • This paper is to suggest policy issues to be done in the future health policy for the elderly, analyzing contents of results suggested in academic papers published in Journal of the Korean Gerontological Society. Number of Papers published in the Journal is 61, occupying most of papers related with chronic disease, medical expenditures and health delivery system except dental and psychiatric health. Method used to be analyzed is mostly random sampling among community inhabitants or hospital patients. Policy issues are as follows in case of being based in the above analysis results. Firstly, it is necessary that the development of health promotion specialized for the elderly be developed and activated. Secondly, it is necessary that the primary health care system specialized for the elderly be constructed. Thirdly, it is necessary that the subacute care system specialized for the elderly be constructed after acute care services. Finally, it is necessary that the health care system specialized for the elderly in need of long-term care be constructed also.