• 비파괴검사학회지
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• 제22권4호
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• pp.386-392
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• 2002

골다공골증은 해면골의 골소주 두께 감소 및 파단에 기인한 전체적인 골질이 저하되는 질병이다. 골다공증의 진단은 X-ray 및 초음파를 이용하는 방법이 있다. 그러나 X-ray 방법은 인체에 해로우며 단지 골밀도만을 평가한다. 대부분 골다공증 진단 초음파 시스템은 heel뼈를 통과하는 초음파 속도 및 감쇠 파라미터를 측정하고 있다. 한편, 기존의 초음파 시스템들은 heel뼈의 한 점에서만 측정을 실행하므로 측정 위치에 따른 오차로 인하여 골다공증의 진단 예측성이 매우 낮다. 본 연구에서는 두 개의 초음파 탐촉자를 이용하여 선형 스캐닝 방식에 의한 heel뼈 전체 영역에 대한 초음파 파라미터 값들은 2차원 영상처리기법을 통하여 골다공증을 진단하는 기법을 수행하였다.

• 대한방사선기술학회지:방사선기술과학
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• 제44권3호
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• pp.211-218
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• 2021

The purpose of this study was to investigate the effect of sex and menopausal age on the thickness and density of squamous portion of the temporal bone as the membranous bone. Patients who visited a general hospital in Chungnam and had a computed tomography (CT) examination of the head. A retrospective study was conducted with 120 subjects (30 men under 55 years old, 30 men over 56 years old, 30 women under 55 years old, and 30 women over 56 years old). Axial images of the squamous portion in the temporal bone were obtained from CT of the head. For this image, a slice sensitive profile (SSP) was acquired with an image analysis program and these were evaluated. The thickness was measured by using a digital ruler to measure the full width at half maximum (FWHM) of the SSP, and the density was measured in hounsfield unit (HU). These by gender were measured to be about 0.5 mm thinner in the temporal bone in men than in women, and there was a significant difference. The density was measured to be about 200 HU higher in women than in men of it, and there was a significant difference. As a result, it in women was thicker and had a lower density. The thickness of it in men and women over 56 years of age was 0.8 mm or more thicker in women and less than 400 HU in density. As a result, the women group over the age of 56 showed a distinct increase in thickness and decrease in density, different from other target groups. It is expected that the results of this study could be used as basic data for a new bone density measurement site study.

• 분석과학
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• 제26권2호
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• pp.125-134
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• 2013

본 연구는 액체크로마토그래피를 이용하여 사골농축액 시료 중에 23종의 아미노산 정량분석 시 발생할 수 있는 측정불확도를 평가하였다. 아미노산 분석에 관여하는 측정불확도 인자로 시료량, 최종 무게, 표준품 무게, 표준품 순도, 검정곡선, 회수율 및 재현성 등을 확인하였다. GUM(Guide to the expression of uncertainty in measurement)과 EURACHEM에 근거하여 측정불확도에 대한 수학적 계산 및 통계분석을 수행하였다. 사골농축액 시료 중 총 아미노산 함량은 36.18 g/100 g이었으며, 95% 신뢰수준(k, 2.05~2.36)에서 확장불확도는 3.81 g/100 g이었다. 측정불확도의 주요 요인은 분석시의 회수율과 반복성(25.2%) > 시료전처리(24.5%) > 검정곡선(24.0%) 순으로 나타났다. 따라서 아미노산 분석 시 불확도를 줄이기 위해서는 실험자들의 주의와 개인적인 숙력도의 향상이 요구된다.

• 대한치과의사협회지
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• 제13권2호
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• pp.107-112
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• 1975

• 대한정형외과스포츠의학회지
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• 제1권1호
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• pp.26-30
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• 2002

목적: 동종골-슬개건-골을이용한전방십자인대재건술시인간골간섭나사못의초기및조기고정력을알아보려고하였다. 대상및방법 : 동종골-슬개건-골을이용한전방십자인대재건술을28 슬관절에대해수술후6주, 12주, 6개월, 1년에추적조사하였다. Lachman test, flexion rotation drawer test, jerk test등의이학적검사를시행하였고KT-1000 측정을동시에시행하여경골의전방전위정도를측정하였다. Lachman test는 0$\~$2mm 전방전위까지를정상으로하였고KT-1000 측정은정상측과비교하여 2mm 이내는정상으로하였다. 마지막검사시M RI를시행하였다. 결과: 단일예를제외하고는모두이학적검사와KT-1000 측정상정상범위에속하였다. 실패한일례는수술소견상이식물이경골터널에서의근위전위되었으며이는넓어진터널을감안하지않고단하나의간섭나사못을사용한기술적실수로평가되었다. 결론: 인간골골피간섭나사못은전방십자인대의재건술을시행하는데충분한초기및조기고정력을보여주었다.

• 대한치과교정학회지
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• 제48권6호
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• pp.367-376
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• 2018

Objective: This study was performed to investigate the changes in alveolar bone after maxillary incisor intrusion and to determine the related factors in deep-bite patients. Methods: Fifty maxillary central incisors of 25 patients were evaluated retrospectively. The maxillary incisors in Group I (12 patients; mean age, $16.51{\pm}1.32years$) were intruded with a base-arch, while those in Group II (13 patients; mean age, $17.47{\pm}2.71years$) were intruded with miniscrews. Changes in the alveolar envelope were assessed using pre-intrusion and post-intrusion cone-beam computed tomography images. Labial, palatal, and total bone thicknesses were evaluated at the crestal (3 mm), midroot (6 mm), and apical (9 mm) levels. Buccal and palatal alveolar crestal height, buccal bone height, and the prevalence of dehiscence were evaluated. Two-way repeated measure ANOVA was used to determine the significance of the changes. Pearson's correlation coefficient analysis was performed to assess the relationship between dental and alveolar bone measurement changes. Results: Upper incisor inclination and intrusion changes were significantly greater in Group II than in Group I. With treatment, the alveolar bone thickness at the labial bone thickness (LBT, 3 and 6 mm) decreased significantly in Group II (p < 0.001) as compared to Group I. The LBT change at 3 mm was strongly and positively correlated with the amount of upper incisor intrusion (r = 0.539; p = 0.005). Conclusions: Change in the labial inclination and the amount of intrusion should be considered during upper incisor intrusion, as these factors increase the risk of alveolar bone loss.

• 대한치과보철학회지
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• 제34권1호
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• pp.70-84
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• 1996

This paper reports marginal bone loss around osseointegrated implants after loading in partially edentulous patients in dental hospital, Yonsei University. Two types of implants($Br{\aa}nemark^{TM},\;IMZ^{TM}$) were used. Through the digital measurement on periapical radiograph around 37 implants in human subjects, marginal bone loss was observed for 24 months after delivery of prostheses. The results were as follows; 1. According to experimental periods marginal bone loss in total implants was 1.775 mm at 12 months, 1.921 mm at 24 months after delivery of prostheses(p<0.05). 2. Marginal bone loss in the $Br{\aa}nemark$ implants was 1.831 mm at 12 months, 1.833 mm at 24 months after delivery of prostheses(p<0.05). 3. Marginal bone loss in the IMZ implants was 1.578 mm at 12 months, 2.907 mm at 23 months after delivery of prostheses(p<0.05). 4. During the first year after loading, the IMZ implants showed less marginal bone loss than the $Br{\aa}nemark$ implants but, during the next the $Br{\aa}nemark$ implants showed less than the IMZ implants(p>0.05). These results indicate that marginal bone loss around osseointegrated implants occurs within the first 12 months after delivery of prostheses and stabilizes thereafter, so it is necessary to be careful of using dental implants for the first year after delivery of prostheses.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권5호
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• pp.417-421
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• 2005

This study was to analyze the changes of levels of alkaline phosphatase before and after enucleation of jaw cysts combined with bone grafting, and to evaluate biochemically the effectiveness of the early detection of bone healing and infection as a prognostic marker. Eighteen patients (13 males, 5 females) with cystic lesions of the jaws were divided into two groups. The bone graft group underwent enucleation and bone graft. The control group underwent only enucleation. Both groups were measured levels of ALP before surgery, and plus-minus 4 weeks postoperatively. The more discriminating results were obtained in the bone graft group. The results were as follows : 1. Levels of ALP after enucleation of jaw cysts were decreased in all patients with and without bone graft. 2. The bone graft group showed more marked decrease in variation of levels of ALP than the control group.(p=0.008) This should be considered as a result of increased osteoblastic activity and new bone formation. 3. Such variation could be used as a prognostic marker for bone healing after cyst operation. In the cost/benefit ratio, measurement of ALP activity could be useful as a convenient procedure in routine clinical practice.

• Journal of Audiology & Otology
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• 제24권2호
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• pp.85-90
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• 2020

Background and Objectives: The present study aimed to compare thresholds of direct bone-conduction (BC direct) with those of behaviorally measured BC pure-tone audiometry (PTA) and objectively measured BC auditory brainstem response (ABR) to confirm the clinical feasibility of their relationships. Subjects and Methods: Young adults with normal hearing participated in the study to determine the thresholds from three measurements at four testing frequencies. In the BC direct, the vibrator of a bone-anchored hearing aid softband was placed on the right mastoid of each subject. In both PTA and ABR, a B71 bone oscillator was placed on the subject's right mastoid. While the subject's thresholds of BC direct and BC PTA were determined with a clinically routine 5-dB step procedure, BC ABR was conducted to determine the individual's hearing sensitivity by a peak V of the waveform using tone-burst and click stimuli. Results: The BC direct showed a different pattern between low and high frequencies. Precisely, its thresholds were 13.25 and 12.25 dB HL at 0.5 and 1 kHz, respectively, but 19 and 19.75 dB HL at 2 and 4 kHz, respectively. A significant positive correlation existed between BC direct and PTA at 1 kHz, which was also correlated with ABR. Conclusions: Based on the current data, the thresholds of BC direct were similar to BC PTA at low frequencies and BC ABR at high frequencies. The thresholds of BC direct might be predictable at approximately 5 dB higher (or lower) than that in PTA, although a large data set is required for standardization.

• 대한청각학회지
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• 제24권2호
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• pp.85-90
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• 2020

Background and Objectives: The present study aimed to compare thresholds of direct bone-conduction (BC direct) with those of behaviorally measured BC pure-tone audiometry (PTA) and objectively measured BC auditory brainstem response (ABR) to confirm the clinical feasibility of their relationships. Subjects and Methods: Young adults with normal hearing participated in the study to determine the thresholds from three measurements at four testing frequencies. In the BC direct, the vibrator of a bone-anchored hearing aid softband was placed on the right mastoid of each subject. In both PTA and ABR, a B71 bone oscillator was placed on the subject's right mastoid. While the subject's thresholds of BC direct and BC PTA were determined with a clinically routine 5-dB step procedure, BC ABR was conducted to determine the individual's hearing sensitivity by a peak V of the waveform using tone-burst and click stimuli. Results: The BC direct showed a different pattern between low and high frequencies. Precisely, its thresholds were 13.25 and 12.25 dB HL at 0.5 and 1 kHz, respectively, but 19 and 19.75 dB HL at 2 and 4 kHz, respectively. A significant positive correlation existed between BC direct and PTA at 1 kHz, which was also correlated with ABR. Conclusions: Based on the current data, the thresholds of BC direct were similar to BC PTA at low frequencies and BC ABR at high frequencies. The thresholds of BC direct might be predictable at approximately 5 dB higher (or lower) than that in PTA, although a large data set is required for standardization.