• Imaging Science in Dentistry
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• 제53권2호
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• pp.137-144
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• 2023

Purpose: This study aimed to evaluate the anatomic circle around the impacted lower third molar to show, document, and correlate essential findings that should be included in the routine radiographic assessment protocol as clinically meaningful factors in overall case evaluation and treatment planning. Materials and Methods: Cone-beam computed tomographic images of impacted lower third molars were selected according to specific inclusion criteria. Impacted teeth were classified according to their position before assessment. The adjacent second molars were assessed for distal caries, distal bone loss, and root resorption. The fourth finding was the presence of a retromolar canal distal to the impaction. Communication with the dentist responsible for each case was done to determine whether these findings were detected or undetected by them before communication. Results: Statistically significant correlations were found between impaction position, distal bone loss, and detected distal caries associated with the adjacent second molar. The greatest percentage of undetected findings was found in the evaluation of distal bone status, followed by missed detection of the retromolar canal. Conclusion: The radiographic assessment protocol for impacted third molars should consider a step-by-step evaluation for second molars, and clinicians should be aware of the high prevalence of second molar affection in horizontal and mesioangular impactions. They also should search for the retromolar canal due to its associated clinical considerations.

• 대한치과보철학회지
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• 제31권4호
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• pp.625-642
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• 1993

Whether stress-absorbing elements are functional in an implant system has been an issue of interest in oral implantology. The unique feature of the IMZ implant system is the planned imitation of the stress-distributing function of the structural unit of the tooth, periodontium, and alveolar bone through the use of an intramobile element(IME). The purpose of this study was to compare the difference in the displacement and the stress distibutions of IMZ implant with a polyoxymethylene(POM) or a titanium IME under static load. Two dimensional finite element analysis(FEA) was applied for this study and two finite element models were created. PATRAN program(DPA Co.,USA), a software for FEA, and SUN-SPARC2GX(SUN Co., USA), a workstation computer, were used. $1Kg/mm^2$ of static load was loaded individually on each three point of crown of implant prosthesis ; central fossa(load 1), mesial cusp tip(load 2), distal cusp tip(load 3), The displacements of X- and Y-axis and total displacement were measured at mesial and distal cusp tips, mesial and distal points between crown and IME, and implant apex. The von Mises stress was measured at mesial and distal points between crown and IME, mesial and distal points between IME and TIE, mesial and distal alveolar crest, the mesial and distal midpoints of implant, and implant apex. The difference in resultant values were compared and evaluated statistically using paired t-test. The results were as follows : 1. Under the load 1, all the displacement of implant with titanium IME at 5 measuring points was larger than that of with POM IME except total and Y-axis displacement at implant apex. And the differences in stress distributions with POM and titanium were varied. 2. Under the load 2, all the displacement of implant with titanium IME at 5 measuring points was larger than that of with POM IME except X-axis displacement at distal cusp tip. And the differences in stress distributions were varied. 3. Under the load 3, all the displacement of implant with titanium IME at 5 measuring points was larger than that of with POM IME except Y-axis displacement at mesial cusp tip. And the differences in stress distributions were varied. 4. For the displacement, there was significant difference statistically only in total displacement (P<0.1), but was no significant difference in X- and Y-axis displacement(P>0.1). For the stress, there was no significant difference among the compared values.

• 대한치과교정학회지
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• 제29권4호
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• pp.425-433
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• 1999

회전된 구치를 개선시키기 위해 사용하는 precision-TPA(transpalatal arch)를 삽입 방법들-근심삽입법, 원심삽입법, 확장력을 부여한 근심삽입법(이하 근심확장법) -에 따라 동적인 치아이동의 양상과 치열궁의 변화를 비교하기 위해 본교실에서 개발, 제작한 Calorific machine을 이용하여 실험한 후 회전된 치아와 고정치간의 이동양상을 계측하여 통계처리한 결과 다음과 같은 결론을 얻었다. 1. 구치간 폭경은 근심삽입법에 의해 감소하였고, 원심삽입법과 근심확장법에 의해서는 증가하였다. 2. 원심삽입법에 의해서 치열궁 장경이 가장 증가하였고, 근심확장법, 근심삽입법 순으로 증가하였다. 3. 근심삽입법의 회전중심은 근심소와(mesial pit)와 중심소와(central pit)사이에 위치하였고, 원심삽입법에서는 원심소와(distal pit)와 원심설측교두(distolingual cusp)사이에, 근심확장법은 원심소와(distal pit)에 위치하였다.

• 한국전문물리치료학회지
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• 제13권4호
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• pp.71-78
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• 2006

This study examined the effects of socket flexion angle in trans-tibial prosthesis on stump/socket interface pressure. Ten trans-tibial amputees voluntarily participated in this study. F-socket system was used to measure static and dynamic pressure in stump/socket interface. The pressure was measured at anterior area (proximal, middle, and distal) and posterior area (proximal, middle, and distal) in different socket flexion angles ($5^{\circ}$, $0^{\circ}$, and $10^{\circ}$). Paired t-test was used to compare pressure differences in conventional socket flexion angle of $5^{\circ}$ with pressures in socket flexion angles of $0^{\circ}$ and $10^{\circ}$ (${\alpha}$=.05). Mean pressure during standing in socket flexion angle of $10^{\circ}$ decreased significantly in anterior middle area (19.7%), posterior proximal area (10.4%), and posterior distal area (16.3%) compared with socket flexion angle of $5^{\circ}$. Mean pressure during stance phase in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (19.3%) and decreased significantly in anterior distal area (19.7%) compared with socket flexion angle of $5^{\circ}$. Mean pressure during stance phase in socket flexion angle of $10^{\circ}$ decreased significantly in anterior proximal area (19.6%) and increased significantly in anterior distal area (8.2%) compared with socket flexion angle of $5^{\circ}$. Peak pressure during gait in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (23.0%) compared with socket flexion angle of $5^{\circ}$ and peak pressure during gait in socket flexion angle of $10^{\circ}$ decreased significantly in anterior proximal area (22.7%) compared with socket flexion angle of $5^{\circ}$. Mean pressure over 80% of peak pressure ($MP_{80+}$) during gait in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (23.9%) and decreased significantly in anterior distal area (22.5%) compared with socket flexion angle of $5^{\circ}$. $MP_{80+}$ during gait in socket flexion angle of $10^{\circ}$ decreased significantly in anterior distal area (34.1%) compared with socket flexion angle of $5^{\circ}$. Asymmetrical pressure change patterns in socket flexion angle of $0^{\circ}$ and $10^{\circ}$ were revealed in anterior proximal and distal region compared with socket flexion angle of $5^{\circ}$. To provide comfortable and safe socket for trans-tibial amputee, socket flexion angle must be considered.

• 비교문화연구
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• 제45권
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• pp.381-431
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• 2016

본고에서는 슬라브어, 특히 러시아어, 폴란드어, 체코어, 불가리아어 담화 직시의 전반적 특징을 살펴본다. 슬라브어에서는 무엇보다도 근칭지시사가 담화 직시사로 기능하는 경향이 강하다는 공통점이 있지만, 개별 슬라브어에서 담화 직시사의 구체적 사용 양상은 상이하다. 폴란드어와 체코어에서는 원칭지시대명사와 인칭대명사가 담화 직시사로 거의 기능하지 못하는 반면, 러시아어는 원칭지시대명사가 담화 직시사로 활발하게 사용되며, 인칭대명사도 사용 가능하다. 불가리아어에서는 원칭지시대명사가 담화 직시사로 거의 사용되지 않는 반면, 인칭대명사는 자주 사용된다. 이와 같이 슬라브어 담화 직시사는 개별 언어에서 상이하게 직시와 대용 기능을 수행하는데, 근칭, 원칭 지시대명사와 인칭대명사가 모두 담화 직시사로 기능하는 러시아어에서는 그것의 직시성이 다른 언어에 비해 두드러지며, 가장 분석적인 슬라브어인 불가리아어에서는 인칭대명사의 사용이 잦아 다른 슬라브어에 비해 담화 직시사의 대용 기능이 두드러진다.

• Korean Journal of Mathematics
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• 제12권2호
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• pp.171-175
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• 2004

The purpose of this paper is to investigate some lifting properties of homomorphisms of flows. It is shown that an almost one to one extension of a minimal proximal flow is proximal. It is also shown that a distal extension of a pointwise almost periodic flow is pointwise almost periodic.

• 한국임상수의학회:학술대회논문집
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• 한국임상수의학회 2008년도 추계학술대회
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• pp.193-193
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• 2008

• 대한정형외과스포츠의학회:학술대회논문집
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• 대한정형외과스포츠의학회 2004년도 The 7th korea-japan joint meeting of orthopaedic sports medicine
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• pp.38-38
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• 2004

• 충청수학회지
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• 제33권2호
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• pp.287-292
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• 2020

In this paper, we prove that a distal homeomorphism f of a compact connected metric space X does not have the eventual pseudo orbit tracing property.

• 대한장애인치과학회지
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• 제9권1호
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• pp.42-45
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• 2013

저자는 de Grouchy 증후군을 가진 4세 여자 환아에 대한 임상적 및 방사선학적 관찰을 통해 다음과 같은 지견을 얻었다. 1. 환아는 de Grouchy 증후군의 증상인 심장 및 발가락의 기형, 근긴장의 저하, 뇌량의 부분적인 무형성, 시각 장애와 청각 장애, 지적 능력의 저하, 성장 발달의 지연 등을 나타낸다. 2. 환아의 구강 및 두개악안면 소견으로 상악골 열성장과 전치부 반대교합을 보이며, 불량한 구강 위생으로 인한 다발성 치아우식증이 관찰된다. 3. 환아의 구강 위생 관리 및 치료 부위의 유지를 위하여 주기적인 치과 검진이 필요하며, 상악골 열성장과 전치부 반대교합을 개선하기 위해 추후 교정 치료가 필요할 수 있다.