• The Journal of Advanced Prosthodontics
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• 제16권1호
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• pp.12-24
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• 2024

PURPOSE. This study aimed to evaluate the maximum vertical wear, volume wear, and surface characteristic of antagonist enamel, opposing monolithic zirconia or lithium disilicate crowns. MATERIALS AND METHODS. The study comprised 24 participants (n = 12), who were randomly allocated to receive either a 5 mol% Y-TZP or a lithium disilicate crown in positions which would oppose the natural first molar tooth. The contralateral first molar along with its antagonist was considered as the enamel opposing natural enamel control. Data collection was performed using an intraoral scanner and polyvinylsiloxane impression. The means of the maximum vertical loss and the volume loss at the occlusal contact areas of the crowns and the various natural antagonists were measured by 3D comparison software. A scanning electron microscope was subsequently used to assess the wear characteristics. RESULTS. The one-year results from 22 participants (n = 11) indicated no significant differences when comparing the zirconia crown's antagonist enamel (40.28 ± 9.11 ㎛, 0.04 ± 0.02 mm³) and the natural enamel wear (38.91 ± 7.09 ㎛, 0.04 ± 0.02 mm³) (P > .05). Also, there is no significant differences between lithium disilicate crown's antagonist enamel (47.81 ± 9.41 ㎛, 0.04 ± 0.02 mm³) and the natural enamel wear (39.11 ± 7.90 ㎛, 0.04 ± 0.02 mm³) (P > .05). CONCLUSION. While some studies suggested that monolithic zirconia caused less wear on opposing enamel than lithium disilicate, this study found similar wear levels to enamel for both materials compared to natural teeth.

• 구강회복응용과학지
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• 제33권4호
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• pp.252-259
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• 2017

목적: 본 연구의 목적은 지르코니아 전장관과 금전장관으로 수복된 임플란트 지지 고정성 보철물의 장착 후 초기 6개월간의 마모를 비교 분석하는 것이다. 연구 재료 및 방법: 2015년 1월부터 2016년 1월까지, 대구치 부위에 임플란트 지지 고정성 보철 수복을 요하는 환자를 대상으로 하였다. 총 47개에 대하여 임플란트 지지 고정성 보철물과 대합치에 대해 조사를 시행하였으며, 보철물 장착 1주 및 6개월 후 보철물 및 대합치를 인상채득 하여 교합면의 형태를 인기 하였다. 인상체를 스캔하여 보철물 및 대합치의 교합면 형태를 비교하여 마모 분석을 시행하였다. SPSS (Version 23.0; SPSS, IBM Corporation, Armonk, USA) 프로그램을 이용하여 정규성 분석 후 Mann-Whitney 분석을 시행하였다. 결과: 임플란트 지지 고정성 보철물에서 지르코니아 전장관과 금전장관 보철물의 6개월간 평균 수직거리 차의 중앙값은 각각 $50.84{\mu}m$, $42.84{\mu}m$로 통계적 유의차가 없었다(P > 0.05). 대합치가 자연치인 경우, 지르코니아 전장관 및 금전장관 보철물의 6개월간 평균 수직거리 차의 중앙값은 각각 $47.72{\mu}m$, $41.97{\mu}m$였으며, 대합치 법랑질의 평균 수직거리 차의 중앙값은 각각 $47.26{\mu}m$, $44.59{\mu}m$이었고, 통계적 유의차는 없었다(P > 0.05). 결론: 조사 기간이 짧았고, 실험군의 개수가 적었다는 단점이 있지만, 임플란트 지지 고정성 보철물 장착 후 초기 6개월간의 마모 비교에서 지르코니아 전장관과 금전장관은 유의한 차이가 없었고, 대합되는 자연치 법랑질의 마모도 유의한 차이는 없었다.

• 한국치위생학회지
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• 제13권2호
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• pp.249-260
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• 2013

Objectives : To figure out the status of infection control (IC) in dental healthcare field and to propose the way for improvements through assessment about cognition of the clients. Methods : Study subjects were 151 patients who visited H dental health organization (DHO) of the four DHO in Busan city. The questionnaire survey performed from November 10 to December 7, 2010. Results : 1. 43.0% of consumers were interested in perception and experience in the infection control, and 38.4% were related behavioral changes in the infection control. 2. In the clients survey, the major considerations about the performance for IC were hand washing(73.5%). 3. There was significantly higher in middle-aged to think for ages infection prevention behaviors recognized as important to wear safety glasses. 4. In the confidence for dental care organization according to gender and age, appearance and outfits of staffs was the highest major consideration items. Conclusions : Infection control closely related to the clients' satisfaction and credits, therefor changing of interest, cognition and attitude for the client's IC have to be emphasized.

• 복식문화연구
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• 제14권1호
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• pp.93-107
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• 2006

This study was designed from the concept that there is a need to establish the uniform for new emerging jobs in modern society. The purpose of the study was to examine dental hygienists'wearing condition, satisfaction, and design evaluation as to provide information for the development of dental hygienists' uniform. Three hundred fifteen dental hygienists completed questionnaires, and data were analyzed by descriptive statistics, factor analysis, multiple regression, ANOVA, and Duncan's test. The findings from the study were following. First, majority of dental hygienists currently wear shirts and pants two-piece uniform in white with no print. Second, dental hygienists' overall satisfaction level for their uniform was medium, and symbolic satisfaction as well as functional satisfaction did not reach the medium level while aesthetic satisfaction was above medium. The satisfaction levels were significant different between groups according to the education, clinic size, and work experience. Third, aesthetic satisfaction levels influenced on the job image as professional. Finally, designs consisting of two-piece style with shirts and pants and having Peter pan collar were recorded high evaluation. The findings can be implemented into dental hygienists' uniform design.

• 대한치과의사협회지
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• 제54권7호
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• pp.492-500
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• 2016

Crown fractures are a common type of dental injuries and very frequently occurred on maxillary anterior teeth, area of requiring a rapid aesthetic recovery. Crown fragment reattachment is a simple and conservative method to restore the fractured teeth. The technique promotes esthetic outcomes as utilizing natural contour, shade, surface texture of teeth and gives mechanical similarity in terms of wear-resistance. Also it gives emotional positive responses to patients and requires less of chair time and costs. This case report presents two cases of crown fragment reattachments on maxillrary anterior teeth, including one complicated crown fracture and one uncomplicated crown fracture. If the fragment is available in cases of crown fractures, reattachment of fragment can be regarded as a predictable alternative. However, it is all the time important that a close conversation informing the patients about the limitations and prognoses of this treatment option.

• The Journal of Advanced Prosthodontics
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• 제2권2호
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• pp.46-49
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• 2010

BACKGROUND. Though implant dentistry is very successful and predictable in treatment of patients with destroyed dentition, there are some cases with limitations to implant therapy. In these cases, alternative treatment modality should be considered. CASE DESCRIPTION. A patient with destroyed dentition was rehabilitated with a lateral rotational path removable partial denture. According to the diagnosis, we determined to raise vertical dimension for esthetic and functional restoration. The final restoration was performed after four months of provisional period. CLINICAL IMPLICATION. The edentulous patients with compromised esthetics and functions can be successfully treated with a rotational path removable partial denture through adequate treatment planning and precise laboratory procedure.

• 대한치과보철학회지
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• 제37권3호
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• pp.328-342
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• 1999

This study was performed to investigate the factors related to tooth wear. For this study, 78 patients with temporomandibular disorders and 76 dental students without any signs and symptoms of temporomandibular disorders were selected as the patients group and as the normal group, respectively. Preferred chewing side, Angle's classification, lateral guidance pattern, head and shoulder posture were observed clinically. Electromyographic activity of anterior temporalis and masseter muscle were recorded with $BioEMG^{(R)}$ and occlusal status were recorded with $T-Scan^{(R)}$. Wear facet area of each tooth was measured from working model of upper arch corresponding to the occlusal status from T-Scan. Wear facet area were measured with planimeter in $mm^2$. Total area were divided into incisal, canine, posterior tooth area. Anterior wearfacet area was incisor area plus canine area, and unilateral area was anterior area plus posterior area. The data collected were analyzed by SAS statistical program and the results of this study were as follows: 1. There was no significant difference between the two groups in total werafacet area, and male subjects showed tendency to have larger area in the normal group but female subjects showed tendency vice versa. 2. There was no significant difference related to preferred chewing side and Angle's classification, however some difference was observed by lateral guidance pattern. Anterior wear facet area in subjects of canine guidance was the largest in the three subgroups. 3. Subjects with head tilting to right side had larger posterior and total area, and subjects with higher shoulder in right side had larger canine and anterior area than any other subgrous. 4. Electromyographic activity of masseter muscle was more correlated with wear facet area than anterior temporalis muscle, and tooth contact number and force were significantly correlated with wear facet area, but the most important factor affecting tooth attrition was age.

• The Journal of Advanced Prosthodontics
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• 제13권3호
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• pp.152-159
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• 2021

Purpose. The aim of this study was to investigate to what extent cyclic load affects the screwless implant-abutment connection for Morse taper dental implants. Materials and Methods. 16 implants (SICvantage max) and 16 abutments (Swiss Cross) were used. The screwless implant-abutment connection was subjected to 10,000 cycles of axial loading with a maximum force of 120 N. For the pull-off testing, before and after the same cyclic loading, the required force for disconnecting the remaining 6 implant-abutment connections was measured. The surface of 10 abutments was examined using a scanning electron microscope 120× before and after loading. Results. The pull-off test showed a significant decrease in the vertical force required to pull the abutment from the implant with mean 229.39 N ± 18.23 before loading, and 204.30 N ± 13.51 after loading (P<.01). Apart from the appearance of polished surface areas and slight signs of wear, no visible damages were found on the abutments. Conclusion. The deformation on the polished abutment surface might represent the result of micro movements within the implant-abutment connection during loading. Although there was a decrease of the pull-off force values after cyclic loading, this might not have a notable effect on the clinical performance.

• 한국치위생학회지
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• 제22권5호
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• pp.333-340
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• 2022

Objectives: This study aimed to confirm the association between cognitive function and oral health status in the elderly. Methods: In this study, 5,794 respondents, aged 55 or older, who had participated in the 7th aging research panel survey were used. Statistical analyses were performed using a complex samples cross-tabulation analysis, complex samples general linear model, and a complex sample multinomial logistic regression analysis. Results: After analyzing the cognitive function of the elderly according to their oral health conditions, it was found that suspicions of dementia (19.6%) and cognitive function decline (25.9%) were more common for those who wore dentures than for those who did not wear dentures (p<0.001). Compared to those who did not wear dentures, those who wore dentures were linked to a 1.665 times higher suspicion of dementia (p<0.001). In comparison, cognitive decline was 0.964 times lower when the number of natural teeth increased by 1, and it was 0.941 times lower when the oral health evaluation index for the elderly increased by 1 point (p<0.001). Conclusions: As a result of this study, it was confirmed that cognitive function and oral health status are related in the elderly. Therefore, systematic measures for oral health management and oral health promotion should be prepared in tandem with awareness of possible cognitive decline in the elderly.

• 한국치위생학회지
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• 제17권5호
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• pp.721-733
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• 2017

Objectives: This study was conducted to help reduce the anxiety about dental radiation exposures of people and to provide a way to instill proper awareness of dental radiation. Methods: To fulfill the research aim, this study conducted a survey to 330 subjects who are 20 years old or over living in Seoul and Gyeonggi-do during the month of December 2016. The collected data were analyzed using frequency analysis, t-test, one-way ANOVA, Pearson's correlation coefficient and multiple regression analysis among others. Results: As a result of examining the correlation between the anxiety of dental radiography and the correlations between the variables showed that the knowledge of radiation knowledge and the need for radiography (r=0.186, p<0.01), thinking about shooting (r=0.137, p<0.05), and the effectiveness of wearing protective equipment (r=0.120, p<0.01), showing statistically significant differences. As a result of examining the factors influencing anxiety of dental radiography among adults, high awareness of the need for dental radiography (p<0.01), the more the idea of dental anxiety in dental radiography is radiography showed higher (p<0.01). Conclusions: It seems proper that adequate dental radiography requires adequate explanation about it to patients, wearing of protective equipment, and appropriate dental radiation safety education.