• 대한치과보철학회지
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• 제56권3호
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• pp.258-268
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• 2018

목적: 본 연구는 보철물의 적합 및 인상의 정확성에 관한 문헌들을 체계적으로 고찰하여 구강 내 스캐너를 이용한 디지털 인상법이 전통적인 인상법을 대체할 만한 정확도를 보이는지 알아보고자 한다. 재료 및 방법: 1997년 8월 1일부터 2017년 7월 31일까지 출판된 영어로 쓰여진 연구를 대상으로 디지털 인상법의 정확성에 대한 문헌을 MEDLINE/PubMed 전자 검색 및 수기탐색을 시행하였다. 조건에 따라 선택된 연구의 데이터를 스프레드 시트에 2명의 검토자가 독립적으로 정리하였다. 결과: 총 35개의 연구가 선택되었고, 26개의 연구는 보철물의 적합성을 비교하였고 9개의 연구는 보철물 없이 스캔 데이터를 통해 인상의 정확성을 비교하였다. 대부분의 연구가 보철물을 이용해 인상법의 정확성을 비교하였다. 결론: 본 고찰에 따르면 자연치열에서 디지털 인상법으로 단일관이나 근원심으로 길이가 짧은 보철물을 제작하는 것은 임상적으로 충분히 신뢰할만한 하다. 그러나 디지털 인상법으로 길이가 긴 보철물을 제작하는 것은 연구가 적어 아직 한계가 있다. 임플란트 보철물 제작에 있어서 구내스캐너를 이용한 디지털 인상법으로 전통적인 인상법을 완전히 대체하기는 아직 어렵다.

• 대한화학회지
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• 제56권6호
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• pp.751-758
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• 2012

교사양성대학으로서 사범대학 화학교육과에 대한 학생들의 정체성을 알아보고자 대구시에 소재한 K대학교 사범대학 화학교육과 학생들을 대상으로 성별, 학년에 따른 진로목표와 대학 생활 계획의 차이를 분석하였다. 학생들에게 대학 생활 계획(로드맵)을 작성하게 하고, 이것을 분석하여 15개의 항목을 도출한 뒤, PASW18 프로그램을 사용하여 자료를 처리하였다. 연구결과 학생들의 성별에 따라 진로목표와 영어공부, 여행, 봉사활동 계획에서 유의한 차이가 있었는데, 여학생들이 남학생들에 비해 의학계 진로와 영어공부, 여행에 대한 관심이 더 높았다. 봉사활동에 대한 관심 또한 여학생들이 더 높았으나 전반적으로 남녀 모두 부족하였다. 학년에 따른 차이는 학년이 낮을수록 의학계진로에 대한 관심과 영어공부, 여행, 학점관리, 교환학생, 장학금에 대한 관심이 높았고, 학년이 높을수록 봉사활동과 스터디, 인터넷 강의에 대한 관심이 높았다. 진로목표에 따른 차이는 영어공부, 여행, 학점관리계획에서 유의한 차이가 있었는데, 의학계열 진학의 필수요소인 영어공부와 학점관리에 대한 관심이 사범계열 진학 학생들 보다 월등히 높았으며, 진로를 정하지 못한 학생들의 여행계획이 진로의 방향을 정한 학생들보다 많았다. 이러한 결과는 학년이 낮을수록, 남학생보다 여학생이 사범대학이 교원양성이라는 목적대학의 정체성을 크게 인식하지 않는다고 판단되며, 그에 따라 대학 생활 계획도 달라짐을 보여준다. 따라서 사범대학의 본래의 특성보다는 현실적인 진로 선택과 생활 계획을 우선시 하는 학생들에 대한 진로 상담 및 지도가 요구되며, 이러한 현실을 고려하여 교사양성대학으로서의 정체성을 갖출 수 있는 화학교육의 방향성을 재고할 필요가 있다.

• 구강회복응용과학지
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• 제19권1호
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• pp.1-6
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• 2003

취약한 구강 건강은 손상된 저작의 기능을 유발할 수 있다. 음식의 선택에서 저작의 기능이 중요한 역할을 하는지는 아직 까지도 논쟁의 여지가 있을지라도, 손상된 저작의 기능은 부적절한 음식의 선택을 하게끔하며, 따라서 영양의 섭취를 변화시킨다. 만약 이러한 가설이 맞다면, 저작 기능의 결핍은 일반적 건강에 해로운 것일 것이다. 취약한 구강의 건강과 특정한 위장의 질환 사이의 관계는 비록 과학적으로 확립되지는 않았을지라도 제안되어 왔다. 공공 건강의 정책은 자연치아를 보존함으로써 적절한 영양의 섭취를 가능케 하는 것을 강조하여야 하며, 치과의사들은 의치의 사용과 관련된 영양의 위험을 의식하여야 할 것이다.

• The Journal of Advanced Prosthodontics
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• 제4권2호
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• pp.76-83
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• 2012

PURPOSE. Zirconia has been used in clinical dentistry for approximately a decade, and there have been several reports regarding the clinical performance and survival rates of zirconia-based restorations. The aim of this article was to review the literatures published from 2000 to 2010 regarding the clinical performance and the causes of failure of zirconia fixed partial dentures (FPDs). MATERIALS AND METHODS. An electronic search of English peer-reviewed dental literatures was performed through PubMed to obtain all the clinical studies focused on the performance of the zirconia FPDs. The electronic search was supplemented by manual searching through the references of the selected articles for possible inclusion of some articles. Randomized controlled clinical trials, longitudinal prospective and retrospective cohort studies were the focuses of this review. Articles that did not focus on the restoration of teeth using zirconia-based restorations were excluded from this review. RESULTS. There have been three studies for the study of zirconia single crowns. The clinical outcome was satisfactory (acceptable) according to the CDA evaluation. There have been 14 studies for the study of zirconia FPDs. The survival rates of zirconia anterior and posterior FPDs ranged between 73.9% - 100% after 2 - 5 years. The causes of failure were veneer fracture, ceramic core fracture, abutment tooth fracture, secondary caries, and restoration dislodgment. CONCLUSION. The overall performance of zirconia FPDs was satisfactory according to either USPHS criteria or CDA evaluations. Fracture resistance of core and veneering ceramics, bonding between core and veneering materials, and marginal discrepancy of zirconia-based restorations were discussed as the causes of failure. Because of its repeated occurrence in many studies, future researches are essentially required to clarify this problem and to reduce the fracture incident.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3645-3649
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• 2014

The aim of this study was to evaluate the efficacy of third-line combined androgen blockade (CAB) therapy for castration-resistant prostate cancer that relapsed after primary and second-line CAB. We retrospectively reviewed the medical records of 52 patients who received first-, second-, and third-line CAB therapy (medical or surgical castration, plus steroidal antiandrogen of chlormadinone acetate, or nonsteroidal antiandrogen of flutamide or bicalutamide). For cumulative analysis, we searched the PubMed database and identified a total of 50 cases published in English. Including our cases, this provided a total of 102 cases for analysis. In our study cohort, 11 cases (21.2%) achieved more than 50% reduction of serum prostate-specific antigen (PSA) on initiation of third-line CAB. We found that third-line CAB with nonsteroidal antiandrogen after second-line CAB with steroidal antiandrogen exhibited favorable results, with a positive response in six of 13 patients (46.2%). Cumulative analysis findings were comparable. Regarding the timing of third-line CAB administration, 15 patients had started at a PSA equal to or less than 4.0 ng/ml, and eight of them (53.3%) showed a positive response to treatment, compared to only three of 37 patients (8.1%) whose PSA at the initiation of third-line therapy was higher than 4.0 ng/ml (p<0.001). We conclude that third-line CAB with nonsteroidal antiandrogen would be particularly useful for patients whose cancer progressed after second-line CAB with steroidal antiandrogen. The timing of treatment seems to be important because the higher the PSA at the start of third-line therapy, the lower the PSA response rate.

• Imaging Science in Dentistry
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• 제42권2호
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• pp.83-88
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• 2012

Purpose : The aim of this study was to investigate the initial effects of maxillary expansion therapy with Hyrax appliance and to evaluate the related changes in maxillary sinus volume. Materials and Methods : Thirty patients (20 females, 10 males; 13.8 years) requiring maxillary expansion therapy, as part of their comprehensive orthodontic treatment, were examined. Each patient had cone-beam computed tomography (CBCT) images taken before (T1) and after (T2) maxillary expansion therapy with a banded Hyrax appliance. Multiplanar slices were used to measure linear dimensions and palatal vault angle. Volumetric analysis was used to measure maxillary sinus volumes. Student t tests were used to compare the pre- and post-treatment measurements. Additionally, differences between two age groups were compared with Mann-Whitney U test. The level of significance was set at p=0.05. Results : Comparison of pre-treatment to post-treatment variables revealed significant changes in the transverse dimension related to both maxillary skeletal and dental structures and palatal vault angle, resulting in a widened palatal vault (p<0.05). Hard palate showed no significant movement in the vertical and anteroposterior planes. Nasal cavity width increased on a mean value of 0.93mm(SD=0.23, p<0.05). Maxillary sinus volume remained virtually stable. No significant age differences were observed in the sample. Conclusion : Hyrax expansion therapy did not have a significant impact on maxillary sinus volume.

• 대한치과교정학회지
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• 제45권6호
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• pp.308-321
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• 2015

Objective: The efficacy of mandibular advancement devices (MADs) in the treatment of obstructive sleep apnea (OSA) ranges between 42% and 65%. However, it is still unclear which predictive factors can be used to select suitable patients for MAD treatment. This study aimed to systematically review the literature on the predictive value of cephalometric analysis for MAD treatment outcomes in adult OSA patients. Methods: The MEDLINE, Google Scholar, Scopus, and Cochrane Library databases were searched through December 2014. Reference lists from the retrieved publications were also examined. English language studies published in international peer-reviewed journals concerning the predictive value of cephalometric analysis for MAD treatment outcome were considered for inclusion. Two review authors independently assessed eligibility, extracted data, and ascertained the quality of the studies. Results: Fifteen eligible studies were identified. Most of the skeletal, dental, and soft tissue cephalometric measurements examined were widely recognized as not prognostic for MAD treatment outcome; however, controversial and limited data were found on the predictive role of certain cephalometric measurements including cranial base angle, mandibular plane angle, hyoid to mandibular plane distance, posterior nasal spine to soft-palate tip distance, anterior nasal spine to epiglottis base distance, and tongue/oral cross sectional area ratio thus justifying additional studies on these parameters. Conclusions: Currently available evidence is inadequate for identification of cephalometric parameters capable of reliably discriminating between poor and good responders to MAD treatment. To guide further research, methodological weaknesses of the currently available studies were highlighted and possible reasons for their discordant results were analyzed.

• Imaging Science in Dentistry
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• 제51권3호
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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.

• 대한치과교정학회지
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• 제51권1호
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• pp.55-74
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• 2021

Objective: To systematically review studies on canine agenesis prevalence in different populations and continents, based on the jaw, sex, location, and associated dental anomalies. Methods: Electronic and hand searches of English literature in PubMed, Web of Science, Scopus, OpenGrey, and Science Direct were conducted, and the authors were contacted when necessary. Observational studies (population-based, hospital/clinic-based, and cross-sectional) were included. For study appraisal and synthesis, duplicate selection was performed independently by two reviewers. Study quality was assessed using a modified Strengthening the Reporting of Observational Studies in Epidemiology checklist, with main outcome of prevalence of canine agenesis. Results: The global population prevalence of canine agenesis was 0.30% (0.0-4.7%), highest in Asia (0.54%), followed by Africa (0.33%), and the least in Europe and South America (0.19% in both continents). Canine agenesis was more common in the maxilla (88.57%), followed by both maxilla and mandible (8.57%), and the least common was mandible-only presentation (2.86%). The condition was more common in females (female:male ratio = 1.23), except in Asia (female:male ratio = 0.88) and Africa (female:male ratio = 1). In Asia, unilateral agenesis was almost twice as prevalent as bilateral, but in Europe, the bilateral form was more common. Conclusions: The overall prevalence of canine agenesis is 0.30%, with the highest prevalence in Asia, followed by Africa, Europe, and South America. The condition is more common in the maxilla than the mandible, and in females than males (except in Asia and Africa), with unilateral agenesis being more common in Asia and the bilateral form showing a greater prevalence in Europe.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제22권2호
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• pp.191-205
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• 2000

The purpose of this study was undertaken to determine the effects of orthognathic surgery on speech. The hyposis stated herein is that functional behaviors of the dentofacial complex, such as speech production, may be adversely affected by deviations of a structural nature(especially, Class III malocclusion). Twenty adults with Class III malocclusion(13 female and 7 male) were studied preoperative, immediate postoperative and either 6 or 12 months postoperative lateral cephalograms. They had mandibular prognathism and had undergone mandible setback operation. The position of tongue, soft palate(Uvula), hyoid bone, respiratory track width, and pharyngeal depth were assessed on lateral cephalograms with 23 cephalometric variables, ANOVA, Paired t-tests and Pearson's product-moment correlation coefficient tests were used to evalute the operative changes in all cephalometric parameters. A experienced speech and language pathologists performed narrow phonetic transcriptions of tape-recorded words and sentences produced by each of the ninth patients and the recording tapes were analyzed by phonetic computer program(Computerized Speech Lab(CSL) Model 4300BI(U.S.A.)) These judges also recorded their ratings of each patient's overall consonants, hypernasality, hyponasality, and articulation proficiency. The results obtained are as follows; 1. There were significant changes in distance of posterior pharyngeal wall to tongue (TI-TW2, TS-TW3) after the surgery at 6 months postoperatively(each p<0.01 p<0.05). 2. The posterior tongue point(TI, TS, PPT) moved posteriorly after surgery and remained to its changed position at 6 months postoperatively(p<0.05). The displacement of tongue was correlated with the movement of mandibular setback amount(p<0.05). The hyoid bone moved posteriorly superiorly after immediate postoperative period. There was significant changes in hyoid bone movement after immediated postoperative period(p<0.05), but returned to its original position during the follow-up period(p>0.05) 3. The soft palate was displaced posteriorly superiorly after immediated operative period and remained to its changed position at 6 months postoperatively(p<0.05). ANS-PNS-SPT angle increasing, PPU-PPPo distance narrowing was showed after surgery, and remained its appearance 6 months postoperatively(p<0.05). 4. There were significant changes in formant value and squre diagram of vowel sound after the orthognathic surgery and the follow-up period. There were significant changes in /ㅅ/sound and posterior tongue sound. 5. The posterior movement of tongue and the posteriosuperior movement of soft palate was correlated with mandibular setback amount after orthognathic surgery. On the vowel squre diagram, the author found that the place of articulation after operation moved downward, backward, upward. 6. In assessing speech abnormalities, dental occlusion should be considered as a contributing factor. The vast majority of subjects with preoperative misarticulations eliminated or reduced their errors following orthognathic surgery. There was significant difference in speech impovement between pre- and postoperation.