• The Journal of Advanced Prosthodontics
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• 제16권3호
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• pp.139-150
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• 2024

PURPOSE. The purpose of this diagnostic study was to assess the accuracy and time efficiency of a digital method to draw the denture foundation extension outline on preliminary casts compared with the conventional technique. MATERIALS AND METHODS. A total of 28 preliminary edentulous casts with no anatomical landmarks were digitized using a laboratory scanner. The outlining of the entire basal seat of the denture was performed on preliminary casts and digitized. Casts with no extension outline were digitized and outlines were drawn using software (DWOS, Straumann). The accuracy of the extension outlined between both techniques was evaluated in the software (GOM Inspect; GOM GmbH) by file superimposition. Specificity and sensitivity tests were applied to measure accuracy. The paired t-test (95% CI) was used to compare the mean total area and the working time. RESULTS. The accuracy ranged from 0.57 to 0.92. The buccal and labial frenulum showed a lower value in the maxilla (0.57); while the area between the retromolar pad and buccal frenulum (0.64) showed a lower score in the mandible. The maxillary denture foundation and the working time for both arches were significantly longer for the digital method (P < .001). CONCLUSION. The denture foundation extension outline exhibited a sufficiently excellent accuracy for the digital method, except for the maxillary anterior region. However, the digital method required a longer working time.

• The Journal of Advanced Prosthodontics
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• 제10권2호
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• pp.113-121
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• 2018

PURPOSE. The aim of this preliminary study was to investigate, for the first time, the effects of addition of titania nanotubes ($n-TiO_2$) to poly methyl methacrylate (PMMA) on mechanical properties of PMMA denture base. MATERIALS AND METHODS. $TiO_2$ nanotubes were prepared using alkaline hydrothermal process. Obtained nanotubes were assessed using FESEM-EDX, XRD, and FT-IR. For 3 experiments of this study (fracture toughness, three-point bending flexural strength, and Vickers microhardness), 135 specimens were prepared according to ISO 20795-1:2013 (n of each experiment=45). For each experiment, PMMA was mixed with 0% (control), 2.5 wt%, and 5 wt% nanotubes. From each $TiO_2$:PMMA ratio, 15 specimens were fabricated for each experiment. Effects of $n-TiO_2$ addition on 3 mechanical properties were assessed using Pearson, ANOVA, and Tukey tests. RESULTS. SEM images of $n-TiO_2$ exhibited the presence of elongated tubular structures. The XRD pattern of synthesized $n-TiO_2$ represented the anatase crystal phase of $TiO_2$. Moderate to very strong significant positive correlations were observed between the concentration of $n-TiO_2$ and each of the 3 physicomechanical properties of PMMA (Pearson's P value ${\leq}.001$, correlation coefficient ranging between 0.5 and 0.9). Flexural strength and hardness values of specimens modified with both 2.5 and 5 wt% $n-TiO_2$ were significantly higher than those of control ($P{\leq}.001$). Fracture toughness of samples reinforced with 5 wt% $n-TiO_2$ (but not those of 2.5% $n-TiO_2$) was higher than control (P=.002). CONCLUSION. Titania nanotubes were successfully introduced for the first time as a means of enhancing the hardness, flexural strength, and fracture toughness of denture base PMMA.

• 대한치과교정학회지
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• 제29권3호
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• pp.349-360
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• 1999

전치부 수직피개 (overbite)는 하악평면, 구개평면 또한 AB 평면의 경사도에 의해 결정된다는 사실이 구명되었으며, ODI (overbite depth indicator)는 overbite의 세 결정요인이라 할 수 있는 FMA, PPA FABA의 합으로 구성되는 것으로 분석되었다. 따라서 ODI와 세 결정요인들과의 상호관계를 기하학적으로 분석하여 그 관계계수를 산출하였다. ODI 정상수치를 나타내는 관계식에 산출된 관계계수를 대압하여 정리하면, ODI norm=$85^{\circ}-0.5PMA-( 1.08 - 0.01FMA)( FABA-81^{\circ})$라는 식이 도출된다. 이는 ODI 정상수치는 절대적 개념이 아니라 개개인의 골격형태에 의해 결정되는 상대적 개념으로 파악해야 함을 의미하는 것이다. 이렇게 산출한 ODI정상수치 (Individualized ODI norm)개념의 임상적 적용과 진단학적 의미에 대하여 구체적으로 논의하였다.

• 한국치위생학회지
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• 제8권2호
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• pp.1-12
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• 2008

The purpose of this study was to examine the state of visiting oral health programs and the opinions of dental hygienists on the programs in a bid to help boost the efficiency of visiting oral health programs, To meet the goals, 341 dental hygienists in public dental clinics across the nation were asked to join a questionaire survey via e-mail in September 2007, After their views were investigated, the following findings were given: 1. In regard to the management of visiting oral health programs, 44,3 percent of the respondents carried out visiting oral health programs, and 48,3 percent of that group did that in association with visiting health care programs, There were differences among the public dental clinics in beneficiaries of visiting oral health programs, beneficiary selection criteria and the details of oral health programs, which indicated the necessity of the development of standardized models. 2. As to difficulties in fulfilling visiting health care programs, a shortage of professional knowledge was viewed as the greatest hurdle, All their scores were above average, which implied that they were not able to perform the programs successfully. 3. As for the necessity and additional expected effects of visiting oral health programs, the largest number of the dental hygienists who carried them out expected that the programs would serve to change the mind-set of locals about themselves, And the others who didn't placed the most emphasis on cooperation from other departments, and the two groups had a statistically significantly different opinion. 4. Concerning the details of visiting health care programs, the dental hygienists who performed the programs found it most necessary to provide oral health education to employees and families to be visited, The others who didn't considered it most necessary to offer oral health education to people to be visited, The necessity of denture and prosthesis was least stressed by both groups, and they took a significantly different view of treatment for dental diseases, denture and prosthesis. 5. Regarding how to bolster visiting health care programs, the dental hygienist group that carried them out put more emphasis on everything suggested in the survey, Specifically, they attached greater importance to securing sufficient budget, establishing legal foundation, setting up an administration system and determining the directions for the programs in a realistic manner, which signified the desperate need for administrative and institutional backing.

• 치위생과학회지
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• 제5권1호
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• pp.19-24
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• 2005

본 연구는 성남시에 거주하는 65세 이상의 노인구강건강상태를 현존영구치아수, 치아우식발생실태, 영구치치료필요자율, 지역사회치주요양필요자율 및 치아보철상태 등을 파악하고 노인구강보건사업에 필요한 구강보건정보 및 기초 자료로 활용하는데 그 목적을 두고 조사한 결과 다음과 같은 결론을 얻었다. 1. 성남시 65세 이상 노인의 치아우식경험율은 남자 98.3%, 여자 99.0%로 나타났고, 우식경험영구치지수는 20.8개 이었다. 2. 65세 이상 노인의 제 3대구치를 제외한 현존영구치아수는 13개로 나타났다. 3. 치주요양필요자율을 조사한 결과 치면세균막관리필요자율 74.9%, 치면세마필요자율 56.2%, 치주조직병치료필요자율은 8.0%로 나타났다. 4. 65세 이상 노인의 전체적인 평균 총의치장착율은 상악 26.1%, 하악 17.8%로 조사되었으며, 총의치장착필요자율은 상악 7.4%, 하악 4.3%로 조사되었다. 5. 성남시는 노인구강건강증진을 위한 목표를 설정하고 노인 구강건강증진 사업을 개발할 필요가 있는 것으로 검토되었다.

• 대한치과기공학회지
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• 제32권4호
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• pp.417-433
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• 2010

Purpose: This study evaluated the manpower planning of dental technicians. Methods: Methods : Survey was conducted regarding subject's general characteristics, characteristics of dental technician's occupational view and working conditions, and reason to enter into branches of the public health enter. The survey sample consisted of 323 dental technicians (221 male/ 102 female). Survey was conducted for one month from August 1 to September 1 in 2010. Following results were obtained. Results: 1. Regarding general characteristics of the subjects, there was a slight male predilection with 68.4%. Subjects in their 40s occupied the highest proportion of 32.2%. Majority of subjects worked in the big cities (71.5%). Favored working places were dental laboratory (57.6%) and dental hospital or dental clinic (19.5%). Although no position is available in the public sector such as public health center or health care civil servant, 9.3% preferred working in the public health center. Public sector is more favored than 2-year technical colleges or dental supply and equipment companies. In respect to education, 57% of the subjects graduated college. 67.8% were married. Subjects who specialize in the porcelain or all-ceramic were 57.9%. With regard to current position, head of the dental laboratory was most common. 2. Following occupation characteristics were found. Economic reason took the highest proportion when deciding their occupation (39.9%) followed by gaining social experience (36.5%). Majority of the subjects (76.5%) wanted to work as dental technicians until their retirement. 71.5% pursuit to become a manager of the dental laboratory. 76.1% agreed on opening a dental technician position in the public health center. Regarding an authority to lead developing the dental technician position in the public sector, majority of the subject chose ministry of health and welfare (35.6%) and Korean dental technologist association (34.7%). Employment (average, 30%) and turnover rate (average, 36.5%) of dental technology college graduates ranged from 40% to 60%. Most important factors for the employment were practical experience (41.2%) and competency (34.4%). With regard to job satisfaction, so-so as 46.7% and satisfactory was 42.7% 3. In respect to the reason for opening a position in the public health center, 'It is needed to continue denture rogram for elderly patients' obtained the highest score (4.14 point). 'Institutional devices are required to open a position for dental technicians as a public healthcare provider' received high score (4.11 point). 4. Concerning the working conditions, 'professional knowledge is required' received the highest score (4.23) followed by 'too short maternity and parental leave' (4.21). 5. Relationship between general characteristics of the subjects and favor of working in the public health center was investigated. Significant differences were found according to the current and favored working area, favored occupation, education level, marital status, and specialty. Working in the public health center was favored by following subjects: working in mid- or small-sized cities (4.16 point, p<0.05); PhD degree-holder (4.59 point, p<0.01). 6. Among general characteristics of the subjects, significant difference of working conditions was found in the following factors: gender; working areas; favored working areas; favored working positions, and education level. Majority of subjects favored working in big cities and currently work in big cities although satisfaction was comparatively low (3.75 score). 7. Future plan to work in public health center was evaluated according to occupational characteristics. Subject's intention to work in the public healthcare center was significantly affected by opening of dental technician position, leading authority, average turnover rate, and factors affecting employment. Working in the public health care center was favored by the following subjects: Dental technicians who actively supported opening of the dental technician position (4.34 point, p<0.001); subjects who thought the Korean dental technologist association is responsible for the opening of positions in the public sector (4.26 point, p<0.001); and subjects who thought that attitude and character are important for the employment (p<0.001). 8. Concerning difference of working conditions according to the occupational characteristics, significant difference was demonstrated by factors such as a reason to choose to be a dental technician, work plan, pursuing position, responsible authority, average employment rate, and job satisfaction. High standard of working conditions was required in subjects who selected to be a dental technician for the leisure time after work (s.05 point, p<0.01), who planted to work until their marriage (4.25 point, p<0.001), and who pursuit to be a manager (3.98, p<0.05). 9. In respect to influence of general characteristics on the advancement to public health centers, the coefficient of determination (R2) was 0.068 and age affected the working condition with significant difference according to the pvalue. 10. Regarding influence of general characteristics on the advancement to public health centers, the coefficient of determination (R2) was 0.335 and work plan, opening of dental technician position in the public sector, and responsible authority had significant influence over the subject's intention to work in the public health center according to the p-value. 11. With regard to the influence of general characteristics on the advancement to public health centers, the coefficient of determination (R2) was 0.091 and reason to choose to be a dental technician, work plan, and responsible authority significantly affected subject's working conditions. Conclusion: Korean society is becoming a super-aged society according to several statistics. As aged population is rapidly increasing, national health insurance plans to cover denture for senior citizen over 75 years old from 2012. Therefore, dental technicians are urgently needed in the public health centers all over the nation. Many subjects in this study planed to work until their retirement and recognized dental technician's expertise. Ministry of health and welfare and Korean dental technologist association should co-operate each other to prepare foundation and institutional devices for dental technicians to advance into the public health center. This will improve oral health of the population. This study showed urgency of medical facilities and services which meets increasing number of aged population and welfare of the population.

• 대한치과보철학회지
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• 제51권3호
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• pp.147-152
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• 2013

연구 목적: 이 연구는 정상배열을 가지고 있는 한국 유치악 성인에서 얼굴형과 성별에 따라 절치유두를 기준으로 한 상악전치의 위치와 견치폭경 계측치를 제시한다. 연구 대상 및 방법: 전남대학교 치의학 전문대학원에 다니는 학생 중 crowding 및 spacing이 없으며, Angles Class I의 정상 교합관계를 가지고 있는 42명을 대상으로 조사하였다. 선정된 학생들의 두부 측면 방사선 사진을 찍고, posterior facial height (PFH)과 anterior facial height (AFH)을 측정하여 PFH / AFH%를 구하여 cephalic type을 나누었다. 그 후 42명의 상악 모형을 준비하여 버니어캘리퍼스로 상악 중절치 절단연에서 절치 유두 중앙까지의 수평거리(A)와 상악 견치간 거리(B)를 계측, 평균값을 구하였으며, SPSS version 15를 사용하여 통계분석 및 유의성을 검토하였다. 결과: Dolichocephalic type을지닌10명에서A의 평균값은 $8.43{\pm}0.61$, B의 평균값은 $36.73{\pm}2.17$으로 나타났다. Mesocephalic type과 brachycephalic type의경우각각A의평균값은 $8.51{\pm}1.27$, $8.76{\pm}1.03$, B의 평균값은 $35.91{\pm}1.86$, $37.34 {\pm}2.23$로 나타났다. 성별에 따른 계측 결과 남성에서A의 평균값은 $8.86{\pm}1.04$, B의 평균값은 $37.60{\pm}0.24$으로 나타났으며, 여성에서A의 평균값은 $8.41{\pm}0.93$, B의 평균값은 $36.18{\pm}2.01$로 나타났다. A값의 경우 남성이 여성보다 큰 값을 보였으나 그 차이는 통계적으로 유의하지 않았다(P>.05). B값의 경우 남성이 여성보다 큰 값을 보였으며, 통계적으로 유의성을 나타내었다 (P<.05). 결론:한국에서 정상 치열 및 교합을 가진 평균 연령 30세, 42명의 학생을 대상으로 조사하였을 때, 절치유두에서 상악 중절치 절단연까지의 수평 거리는 cephalic type이나 성별에 따른 차이가 없었고, 견치 교두정간 거리는 cephalic type에 따른 차이가 없었지만, 성별에 따라 유의한 차이를 보였으며 남성이 여성보다 큰 값을 나타냈다.