수종의 내부연결형 임플란트에서 연결부의 형태에 따른 응력분포의 유한요소 분석

정병현,이경제,강동완 대한치과보철학회 2012 대한치과보철학회지 Vol.50 No.2

Purpose: This study was performed to compare the stress distribution pattern of abutment-fixture connection area using 3-dimensional finite element model analysis when 5 different implant systems which have internal connection. Materials and methods: For the analysis, a finite element model of implant was designed to locate at first molar area. Stress distribution was observed when vertical load of 200 N was applied at several points on the occlusal surfaces of the implants, including center, points 1.5 mm, 3.0 mm away from center and oblique load of 200 N was applied 30º inclined to the implant axis. The finite element model was analyzed by using of 3G. Author (PlassoTech, California, USA). Results: The DAS tech implant (internal step with no taper) showed more favorable stress distribution than other internally connected implants. AS compare to the situations when the loading was applied within the boundary of implants and an oblique loading was applied, it showed higher equivalent stress and equivalent elastic strain when the loading was applied beyond the boundary of implants. Regardless of loading condition, the abutments showed higher equivalent stress and equivalent elastic strain than the fixtures. Conclusion: When the occlusal contact is afforded, the distribution of stress varies depending on the design of connection area and the location of loading. More favorable stress distribution is expected when the contact load was applied within the diameter of fixtures and the DAS tech implant (internal step with no tapering) has more benefits than the other design of internally connected implants. 연구 목적: 본 연구는 3차원 유한요소분석을 통해 특징적인 내부연결구조를 갖는 5종의 임플란트의 고정체와 지대주의 연결방식에 따른 응력분산을 알아보고자 하였다. 연구 재료 및 방법: 본 실험을 위한 유한요소모델은 하악 제1대구치부에 임플란트가 식립되고 상부구조물로 3형 금합금을 사용하는 것으로 가정하였다. 응력분산은 200 N의 하중이 교합면의 중심, 중심에 1.5 mm 외측, 중심에서 3.0 mm 외측에 수직으로 가해지고 임플란트의 장축과 30º의 각도로 경사하중이 가해지도록 하여 분석하였다. 유한요소모델에 대한 해석작업은 3G.Author (PlassoTech, California, USA)를 사용하여 이뤄졌다. 결과: 경사가 없는 내부계단 구조를 가지는 DAS tech의 임플란트의 경우, 내부연결구조를 갖는 다른 임플란트에 더 유리한 응력분산을 보였다. 하중이 임플란트 고정체의 외형선 이내에 가해지는 경우와 비교하여 외형선 바깥이나 경사력으로 전해지는 경우 더 높은 응력을 보였으며 하중조건과 관계없이 임플란트 고정체보다는 지대주에 더 큰 응력이 집중되었다. 결론: 교합력이 가해졌을 때 응력분산은 임플란트의 연결부의 형태와 하중이 가해지는 위치에 따라 달라졌으며 내부계단 구조를 가지는 DAS tech의 임플란트를 사용한 경우와 고정체의 외형선 이내에 하중이 가해졌을 경우에 더 유리한 응력분산을 보였다.

The effect of degree of daily water intake and skin barrier function

( Gyeong Je Cho ),( So Hee Park ),( Do Hyeong Kim ),( Jung Eun Seol ),( Hyojin Kim ) 대한피부과학회 2017 대한피부과학회 학술발표대회집 Vol.69 No.2

Background: It is well recognized that adequate water intake causes favorable effect in barrier function. However, there have been few studies supporting it in Korea. Objectives: This study was conducted to analyze the effects of the degree of daily water intake on barrier function and response to barrier recovery treatment. Methods: This study enrolled healthy female volunteers. Subjects who answered daily water intake more than 1L on questionnaire were classified as high daily water intake group(H) and those with less than 1L as low daily water intake group(L). Each group were subcategorized into 4 groups according to intervention: water intake(H1, L1), moisturizer(H2, L2), both(H3, L3) and control(H4, L4). Transepidermal water loss(TEWL) and stratum corneum hydration(SCH) were measured at baseline, 2nd and 4th week. Results: A total of 50 subjects were enrolled(H: 24, L: 26) and of them, 43 subjects completed the trial(H: 22, L: 21). At baseline, H1~4 showed higher SCH value both in cheek(64.1) and forearm(41.8) compared with L1~4(59.9, 41.3). The mean change of SCH(mΔSCH) in cheek for 4 weeks was higher in group H1(3.1) compared with L1(0.6), so was H2(7.9) compared with L2(0.6). The mΔSCH of forearm(H1~3: 20.5, L1~3: 13.0) was higher than that of cheek(H1~3: 3.3, L1~3: 0.8) in both groups and those of H group was more prominent. Conclusion: It is suggestive that the degree of water intake might be related to favorable skin barrier function and readiness of beneficial change of it.

A case of marginal zone B-cell lymphoma clinically mimicking rosacea

( Gyeong Je Cho ),( Seong Min Hong ),( Jong Uk Kim ),( Woo Jung Jin ),( So Hee Park ),( In Ho Park ),( Jung Eun Seol ),( Hyojin Kim ) 대한피부과학회 2019 대한피부과학회 학술발표대회집 Vol.71 No.1

A 36-year-old man complained of pruritic erythematous papules, nodules on glabella and both cheeks started from 1 year ago. The lesions were aggravated in hot circumstances and he was treated with topical agent in diagnosis of rosacea at local clinic for 6 months. In suspicion of granulomatous rosacea or lupus erythematosus, skin biopsy was done. There was no change of epidermis with subepidermal Grenz zone and dense nodular aggregation of small-to-medium irregular sized lymphocytes in perifollicular areas, where CD20 and Bcl-2 stains were positive and CD3, CD10, and Bcl-6 stains were negative. He was diagnosed as marginal zone B-cell lymphoma and evaluated for presence of systemic involvement. The final diagnosis was stage IV secondary marginal zone B-cell lymphoma and he is on treatment with chemotherapy. Marginal zone B-cell lymphoma is an indolent tumor that involves mucosa-associated lymphoid tissue. Cutaneous manifestation includes erythematous to violaceous solitary or multiple papules, plaques or nodules. Since the disease shows nodular to diffuse infiltrates along adnexal structures, its cutaneous manifestation may be similar to skin diseases with perifollicular lymphocytic aggregation. Because the secondary marginal zone B-cell favors head and neck, differential diagnosis with rosacea is critical. Herein, we report this case emphasizing one should suspect of lymphoma in treatment-resistant rosacea patient.

A case of foreign body granuloma caused by “Bong-chim” at the site of postherpetic neuralgia

( Gyeong Je Cho ),( Jong Uk Kim ),( So Hee Park ),( Jung Eun Seol ),( Hyojin Kim ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.1

A 63-year-old female patient presented with a 1-year history of asymptomatic atrophic plaques with multiple hard nodules in a dermatomal distribution from her left abdomen to the left back, which were clinically suspected as morphea. Two years ago, she had experienced herpes zoster at the same area. Although she took antiviral medication with analgesics, she suffered from postherpetic neuralgia for a year and eventually visited an oriental medical clinic to get Bong-chim on the area. After 6 months, hypopigmented and atrophic patch with uneven bumpy lesions developed on the acupunctured site. Histopathologic examination revealed granulomatous inflammation at the lower dermis and subcutis, composed of histiocytes and multinucleated giant cells with various sized vacuoles. She was diagnosed with foreign body granuloma and treated with triamcinolone intralesional injections several times, but she has not shown any improvement yet. Foreign body granuloma is one of the possible adverse events from acupuncture and it usually occurs as an inflammatory reaction of foreign bodies that incidentally or intentionally injected. This case presents a foreign body granuloma caused by honeybee acupuncture at the site of postherpetic neuralgia, and calls for caution and awareness of side effects of the acupuncture-related procedures.

A case of fire coral dermatitis after scuba diving

( Gyeong Je Cho ),( Jong Uk Kim ),( So Hee Park ),( Jung Eun Seol ),( Hyojin Kim ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.1

A 29-year-old female presented with erythematous to purpuric patches, pustules on right hand accompanying burning sensation and pain. The patient stated injury had occurred after direct contact with marine organism resembling coral during scuba diving in Philippines. A biopsy specimen showed epidermal necrosis, suppurative exudate in horny layer and perivascular, interstitial neutrophil infiltration with nuclear debris in dermis and subcutis. Although angio-computed tomography showed no evidence of vascular lesion at right upper extremity, she complained of coldness and numbness with edema on right hand. She took systemic corticosteroid, antibiotics and calcium-channel blocker and applied heat lamp, resulting in skin lesion improvement with scar formation.Fire corals are named from the painful stings they inflict on divers, but they are not true corals. They are members of Hydrozoa, which are more related to jellyfish. They have yellow-green or brown skeletal covering and are widely distributed in tropical waters. Contact with protruding nematocysts cause more intense pain and even full-thickness burns. There have been increasing numbers of cases of coral dermatitis as traveling to tropical countries and interest to marine activities increase among Koreans. Thus, we experienced a rare case of dermatitis with severe symptom after immediate contact with corals which is strongly suspected as fire coral and report it with literature review.

A case of eruptive syringoma on forehead in a 9-year-old boy

( Gyeong Je Cho ),( Jong Uk Kim ),( So Hee Park ),( Jung Eun Seol ),( Hyojin Kim ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.1

A 9 year-old boy visited our clinic with 1-3mm sized multiple skin-colored papules distributed on forehead without symptom. There was no family or medical history. Histopathologic examination showed cysts including eosinophilic materials along upper dermis and many tubular structures encompassed by fibrous stroma. Each tubular structure was lined by two layers of epithelial cells which sometimes were elongated forming cord-like tale. He was diagnosed as eruptive syringoma based on the clinical and histological features and on observation without any treatment. Syringoma is a common benign tumor of eccrine sweat gland origin, which usually appears on the eyelids of middle-aged women. In the meantime, eruptive syringoma is a rare clinical variant of syringoma that appears on anterior surfaces of the body including neck, chest, and inner surfaces of extremities in earlier ages. Histopathologic features include upper and mid-dermal proliferation of eccrine duct and elongated epithelial cords in a collagenous stroma which make typical “comma” or “tadpole” appearance. Surgical or chemical therapies are used to manage eruptive syringoma, but there has been no satisfactory treatment. There are 4 patients of syringoma whose age is younger than 10 years old among reports in Korea. Since our case showed all of uncommon manifestations of age, clinical type, it seems valuable to report it as an unusual case of eruptive syringoma in childhood.

A case of deep fungal infection by Purpureocillium lilacinum in an immunocompetent patinet

( Gyeong Je Cho ),( Jong Uk Kim ),( So Hee Park ),( Jung Eun Seol ),( Hyojin Kim ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.1

P. lilacinum is a genus of saprophytic fungus, commonly isolated from soil. Although it is known as a rare pathogen to human, it can cause serious infections in immunocompromised patient. The majority form of the infection is iatrogenic keratitis or endophthalmitis, and cutaneous infections are the second most common form, which account for 35%. Cutaneous infection by P. lilacinum commonly occurs in immunocompromised hosts. An 85-year-old female presented with pruritic erythematous plaques with yellowish crusts on her right forearm and hand. She denided underlying diseases and trauma history. Histopathologic findings showed fungal hyphae and spores in periodic acid-Schiff and Gomori methenamine-silver stains. P. lilacinum was identified through tissue culture, polymerase chain reaction and DNA sequencing. The skin lesion hardly responded to the medication of itraconazole for 4 weeks. Twelve weeks of treatment with combination therapy of itraconazole and terbinafine, the skin lesion was completely cured without recurrence to date. In this case, it is assumed that the patient’s agricultural life style and old age may have increased the chance of the infection of P. lilacinum. Here, we report a case of a deep fungal infection by P. lilacinum in an immunocompetent patient.

A study about the importance of constant temperature and humidity system in analyzing skin barrier function

( Gyeong Je Cho ),( Jong Uk Kim ),( Woo Jung Jin ),( So Hee Park ),( Seung Hyun Moon ),( Jung Eun Seol ),( Hyojin Kim ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.2

Background: Measurements of skin barrier function are easily affected by external environment such as temperature and humidity, especially in Korea where there are distinct four seasons. Objectives: This study was conducted to analyze the variation in measurement of skin barrier function with or without thermohygrostat conditioning in each season. Methods: The study enrolled 10 healthy females who aged 28 to 34. Each subject was put into a room with a thermohygrostat facility. Transepidermal water loss (TEWL) and stratum corneum hydration (SCH) were measured before (uncontrolled value) and after operation of a thermohygrostat facility for 20 minutes (controlled value) in the middle of each season. Results: The measurements under controlled condition (TEWL 3.20±1.97, SCH 13.10±9.26) showed less variation compared with those under uncontrolled condition (TEWL 3.95±2.03, SCH 13.35±10.30), but there was no statistical significance (p>0.05). The difference between two conditions was statistically significant only in summer (TEWL p=0.005, SCH p=0.001). Conclusion: Although the study did not show statistical significance, the thermohygrostat could preserve skin barrier function from the external environment to some extent. Thus, it is regarded that a room equipped with a thermohygrostat could help measure more exact skin barrier function to exclude the influence of surrounding environment, especially in summer season.

Analysis of androgen excess in female pattern hair loss under 30 years old

( Gyeong Je Cho ),( Jong Uk Kim ),( Woo Jung Jin ),( So Hee Park ),( Seung Hyun Moon ),( Jung Eun Seol ),( Hyojin Kim ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.2

Background: Pathogenesis of female pattern hair loss (FPHL) is related to androgen, however its role is not fully understood. In addition, well-known androgen such as testosterone and dehydroepiandrosterone sulfate (DHEA-S), is not considered as sufficient marker for hormonal irregularities in FPHL. Objectives: We investigated this study to identify the characteristics of young female pattern hair loss (FPHL) in regard to androgenic traits. Methods: We reviewed clinical features, laboratory data, ultrasonographic features of ovary, and trichoscopic findings in mid-frontal area in FPHL subjects under 30 years old. Results: A total of 50 female patients were enrolled. The mean age of the patients was 21.5 years old, and the mean onset of the disease was 19.2 years old. A third of subjects (13/42) showed clinical hyperandrogenism signs other than FPHL, but the number of subjects with BMI under 25 (19/22) was much higher than those over 30 (2/22). The ratio of abnormal value (43.3%, n=30) in anti-Mullerian hormone (AMH) was higher than that of total testosterone (23.3%) and DHEA-S (13.3%). The percentage of vellus hair in trichoscopic findings was higher in subjects with abnormal results in AMH, total testosterone, and DHEA-S (p>0.05). Most subjects (30/35) were satisfied with Rotterdam criteria of polycystic ovarian syndrome. Conclusion: It is probable AMH could be more sensitive and useful marker in assessing hormonal irregularities as well as predicting progression in young FPHL.

A case of primary cutaneous CD30 positive anaplastic large cell lymphoma in a patient with granulomatous mycosis fungoides

( Gyeong Je Cho ),( Jong Uk Kim ),( So Hee Park ),( Jung Eun Seol ),( Hyojin Kim ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.1

A 54-year-old man visited our clinic complaining of hyperpigmented scaly patches on his left buttock emerged from several years ago and biopsy was done. Under unclear diagnosis of interstitial granuloma annulare, he was treated with 4 times of intralesional triamcinolone injections. The lesion showed little improvement and the patient was lost. Two years later, he presented with an erythematous plaque on his left wrist which turned out to be a primary cutaneous CD30+ anaplastic large cell lymphoma (pcALCL) by histopathologic examination. After two months, new nodules developed at the wrist lesion and previously consulted buttock lesion also aggravated and slightly slack, and they were re-biopsied respectively. The buttock lesion was diagnosed as granulomatous mycosis fungoides (MF) and the nodule at wrist was compatible with pcALCL. Since both of primary cutaneous anaplastic large cell lymphoma and large cell transformation of MF may exhibit CD30+ lymphocytes, it is a hard challenge to differentiate them. However, it is important to make clear diagnosis in that they have divergent prognosis and therefore require different therapy. Thus, we present a rare type of MF misdiagnosed as inflammatory skin disease and coexistent with pcALCL for deeper understanding of the cutaneous lymphoma entity.