열적 변화를 이용한 실내환경 가스의 분류

최낙진,심창현,송갑득,주병수,이윤수,이상문,이덕동,허증수 한국센서학회 2002 센서학회지 Vol.11 No.5

단일 기판위에 온도측정용 Pt 박막과 Pt 히터 그리고 가스 감지를 위하여 순수한 SnO_2 박막과 Pt가 첨가된 SnO_2박막을 설계하고 제작하였다. 제작된 소자는 실내환경가스인 이산화탄소, 프로판 그리고 부탄의 분류에 응용되었다. 동작 온도를 가변하기 위하여 히터의 입력 전압을 사다리꼴로 인가하면서 SnO_2 감지막의 반응특성과 실내환경가스들에 대한 분류여부를 조사하였다. 감지막 반응특성곡선에서 여러 변수들을 추출한 후 주성분분석(principal component analysis : PCA)을 통하여 가스 분류 특성을 검증하였다. Two SnO_2 based sensing films(pure SnO_2 and SnO_2/Pt) and a Pt thin film for temperature sensor on an alumina substrate were designed and fabricated for classifying the indoor environmental gases. By controlling the heating power in the shape of trapezoid, unique four sensing response curves created from both SnO_2 film and SnO_2/Pt film. Then, various parameters were extracted from sensing response curves and carried out principal component analysis(PCA). The results confirm that a sensor array with the proposed operating mode was extremely effective in classifying indoor environmental gases such as CO_2, C_3H_8, C_4H_10.

유절기 조기 상실 후 공간 상실

최병재,한연선,김성오,이종갑 大韓小兒齒科學會 2002 大韓小兒齒科學會誌 Vol.29 No.3

유치에서의 조기 상실은 부위에 따라 주된 원인이 다르다. 구치부의 조기 상실은 주로 치아우식증에 의해 일어나지만, 전치부에서 나타나는 조기 상실의 대부분은 유아가 서고 걷는 것을 배울 시기에 외상을 받아 유발되며, 다발성 우식증 등에 의해서도 일어날 수 있다. 유치의 조기 상실시 치열궁 길이 감소가 나타날 경우에는 계승 영구치의 맹출을 방해하여 영구치의 총생, 매복 및 치열궁 비대칭 등을 유발할 수 있으므로, 공간 유지에 대한 고려가 필요하다. 유구치가 조기 상실된 경우에는 인접치아의 근심 또는 원심 이동으로 공간 상실이 유발되므로, 공간유지장치의 장착이 필수적이다. 그러나, 유절치의 경우에 있어서는 치아간의 접촉이 긴밀하거나 총생이 있는 유치열이 경우와 유견치의 맹출 전에 유절치가 상실된 경우에는 공간 상실이 일어날 수 있으나, 그 이외에 치간 공간이 있는 유치열이 경우, 유견치의 맹출 후에 유절치가 상실된 경우에서는 공간의 상실이 거의 없는 것으로 알려져 있다. 따라서 유절치 조기 상실 시에는 주로 공간유지 목적보다는 심미, 발음장애, 치아결손부분으로의 혀내밀기 등의 구강습관 방지 등의 목적으로 장치의 장착이 권장되어져 왔으며, 유절치 조기 상실시 공간 상실 문제에 대한 증례보고 또한 많지 않다. 본 증례들은 연세대학교 치과대학병원 소아치과에 내원한 환자에게서 유절치의 조기 발거로 인해 장기적 관찰 결과 공간 상실이 유발되었기에 이를 통하여 유절치 조기 상실시 공간 상실 가능성에 대해 보고하고자 한다. The primary cause of missing teeth vary depending on the region. The loss of posterior teeth is mainly due to dental caries, whereas that of the anterior teeth occur primarily due to trauma at the age of standing and walk-ing and secondarily from the rampant dental caries. Particularly, reduction of the arch length in the cases of premature loss of primary teeth may compromise the eruption of succedaneous permanent teeth. This may result in crowding and impaction of the permanent teeth, and asymmetry of arch, thus a careful consideration for space maintenance should be made in such cases. Space maintainer is required in the case of premature loss of primary posterior teeth, because space loss result from the approximate and centrifugal movement of the neighboring teeth. Generally, in the case of primary in-cisor, space loss occurs when 1) tooth contact is relevant, 2) crowding in primary dentition is present, and 3) a primary incisor is lost before the eruption of primary canine. Contrarily, in the case of primary dentition with in-terdental space, space loss will not be observed, mostly when a primary incisor is lost after the eruption of pri-mary canine. Thus, using a space maintainer in cases of premature loss of primary incisor has been introduced primarily not for the purpose of space maintaining but for an aesthetic purpose, prevention of parafunctional oral habits such as tongue thrust, and of pronunciation. Additionally, few case studies have been reported of space loss in cases of premature loss of primary incisor. This study is to report cases of the space loss following the premature loss of primary incisors observed in chil-dren.

유착 유구치의 처치에 관한 증례보고

최병재,이제호,장미라,이종갑 大韓小兒齒科學會 1997 大韓小兒齒科學會誌 Vol.24 No.3

Ankylosis is defined as a fusion of alveolar bone with dentin and/or cementum and may occur at any time during or following active eruption. Ankylosed teeth maintain existing occlusal levels while adjacent teeth continue to erupt via deposition of alveolar bone. This may result in th clinical apperarance of depression or submergence of ankylosed teeth below the occlusal plane. It is found more frequently in children of late mixed dentition and in mandibular primary molars. The problems arising from ankylosed teeth, due to their submerged positions, are elongation of the antagonist, tipping of the adjacent teeth, loss of arch length, food impaction and subsequent destruction of periodontal tissue, disturbance of succedaneous tooth eruption. The author observed several cases fo ankylosed primary molars and properly managed. Following results were obtained. 1. Severe infraoccluded ankylosis results in loss of arch length and undesirable effect on eruption path of succedaneous tooth, therefore early diagnosis and management are important. 2. The teeth without problems may be examined periodically and restored in order to maintain the normal occlusal function.

수종의 저장용액에서 치주인대세포의 생존율 비교

최원경,최병재,최형준,이종갑 大韓小兒齒科學會 1999 大韓小兒齒科學會誌 Vol.26 No.2

치아탈구 발생시 사고 현장에서 쉽게 구할 수 있는 저장용액을 이용하여 치주인대세포의 생존율을 비교해보고자 치주인대세포를 10%FBS함유 α-MEM에서 배양한 후 α-MEM에서 저장한 군을 대조군으로 하고 동일한 조건하에서 저온살균된 우유군, 멸균된 생리적 식염수군, 비자극성 타액군, 건조된 상태로 방치한 군을 실험군으로 하여 25℃ 실온에서 세포 배양 30, 60, 90, 120, 180분 후에 각 군에 대해 MTTassay를 시행하여 다음과 같은 결론을 얻었다. 1. 각 조사시점에서 실험군간의 비교에서는 모두 유의성있는 차이를 보였으며 저온살균된 우유군에서 치주인대세포의 생존율이 가장 높았고, 멸균된 생리적 식염수군, 비자극성 타액군, 건조된 상태로 방치한 군 순으로 점차 감소하였다.(P<0.05) 2. 각 실험군내에서 조사시점간의 비교에서는 치주인대세포의 생존율이 시간이 경과함에 따라 유의성있게 감소하였으나(p<0.05). 저온살균된 우유군에서 90-120분 경과 사이. 멸균된 생리적 식염수군에서 60-90분과 120-180분 경과 사이에서는 유의성있는 차이는 없었다.(P>0.05) 이상의 결론을 종합해볼 때 외상으로 인한 치아탈구 발생시 저장용액으로 HBSS가 추천되고 있으나 사고 현장에서 쉽게 구할 수 있고 치주인대세포의 생활력 보존에도 유리한 저온살균된 우유에 탈구된 치아를 담가오도록 추천할 수 있겠다. Preservation of the remaining periodontal ligament cells on an avulsed tooth is very important to the successful outcome of replantation. HBSS is recommended as the most suitable storage medium for the avulsed tooth that cannot be replanted immediately. But their availability near the site of an accident is doubtful. The purpose of this in vitro study was to compare periodontal ligament cells stored in different storage media obtained easily on th spot. Human periodontal ligament cells were collected from the premolar teeth extracted for orthodontic treatment. Cells were cultured in α-MEM culture medium containing 20% FBS, at 37℃ 100% humidity, in a 5% CO₂2 incubator. Cells were cultured in 96 well culture plate, 5×10⁴cells per well with α-MEM and incubated for 24 hours.After discarding the medium, those cells were cultured in α-MEM contained with 10% FBS, pasteurized milk, sterilized saline, unstimulated saliva and bench-dried state at 25℃ room temperature for 30, 60, 90, 120, 180 minutes respectively. And then each group was measured using MTT assay. The results were as follows. 1. Between the group of each time, there was statistically significant difference. Periodontal ligament cells viability was highest in pasteurized milk and was reduced stepwisely in sterilized saline, unstimulated saliva and bench-dried state(p<0.05) 2. between the time of each group, there was statistically significant difference (p<0.05) but was no statistically significant difference at 90 - 120 minutes in pasteurized milk and at 60 - 90 minutes and 120 - 180 minutes in sterilized saline(p>0.05). In conclusion, HBSS as storage medium of an avulsed tooth is not practical on the spot. Insteadily pasteurized milk can be recommended to maintain the periodontal ligament cells viability.

상악 영구 중철지의 외상성 치근파절 : 증례보고 A CASE REPORT

최형준,곽지윤,이종갑,최병재 大韓小兒齒科學會 2003 大韓小兒齒科學會誌 Vol.30 No.3

청소년기에는 두개악안면부위의 외상성 손상이 흔하다. 그러나 상아질, 백아질, 치수를 포함하는 치아파절로 정의되는 치근파절은 비교적 드물다. 치근파절에 대하여 취할 수 있는 적절한 조치는 파절편의 치관부위를 재위치시키고, 2∼3달간 레진강선 고정술을 시행하는 것이다. 치수과사나 치근흡수의 징후가 나타날때까지 근관치료를 보류해야 하는데 대부분의 증례에서 파절편의 치근부위는 그 생활력을 유지하기 때문이다. 본 증례의 10세 4개월된 남아는 상악영구중절치의 치근파절을 주소로 연세대학교 치과병원에 내원하엿으며, 그후 7년동안 동일부위에 2번의 반복적인 외상이 있었으나 파절편 치관부의 재위치, 레진 강선 고정술, 근관치료 시행 후 임상적으로 방사선학적으로 비교적 양호한 치료결과를 얻었기에 보고하는 바이다. Traumatic injuries in the young permanent dentition are common, but root fractures, defined as fractures in volving dentin, cementum and pulp, are relatively uncommon. Appropriate management of root fracture involves repositioning the coronal portion of the tooth fragment and firm immobilization with a splint for 2 to 3 month. Root canal treatment should not be initiated until the sign of necrosis or resorption are apparent because in most cases, the apical fragments maintain their vitality. The following case report describes a patient with root fractures injured three times over the period of 7 years. The results, clinically and radiographically, were acceptable, but term periodic evaluation is required.

Peripheral, soft tissue odontoma에 관한 증례보고

이종갑,최병재,최형준,이광출 大韓小兒齒科學會 1999 大韓小兒齒科學會誌 Vol.26 No.1

1. Peripheral odontoma는 매우 드문 질환으로 확진을 위해서는 생검이 필수적이다. 2. Peripheral odontoma는 치은의 종창을 동반하며 서서히 성장하는 임상적 특징을 가진다. 3. 골내 치아종과 마찬가지로 Peripheral odontoma의 치료로는 완전한 외과적 절제가 추천되고 예후 또한 양호하다. Odontomas, hamartomas of odontogenic origin, are composed of all the structures that make up teeth. The WHO distinguishes odontoma into two types. The complex odontoma is defined as "a malformation in which all the dental tissues are represented, individual tissues being mainly well-formed but occurring in a more or less disorderly pattern." The compound odontoma is defined as "a malformation in which all the dental tissues are represented in a more orderly pattern than in the complex odontoma, so, that the lesion consists of many toothlike structures. Most of these structures do not resemble morphologically the teeth of normal dentition, but in each one enamel, dentine, cementum, and pulp are arranged as in the normal tooth." Almost all odontomas are located intraosseously, but they have occasionally been reported in extrabony location. Peripheral or soft tissue odontomas, those arising outside of the alveolar bone, are very rare. Peripheral or soft tissue odontoma are defined as tumors that demonstrate the histologic characteristics of their intraosseous counterparts but occur solely in the soft tissue covering the toothbearing portion of the mandible and maxilla, When they mature, they appear as a radiopaque mass without the peripheral halo. The final diagnosis should be confirmed by biopsy. The origin of peripheral odontoma is probably related to remnants of the dental lamina in the gingiva. The treatment of choice is complete surgical excision, similarly to intraosseous odontoma and it does not tend to recur. This report presents a case of 5-year-old boy with swelling on labial gingiva of primary central incisor. And it was diagnosed as peripheral odontoma by excisional biopsy.

아동의 Etched cast restoration을 이용한 영구전치 상실 치료증례

이종갑,최병재,김종필 大韓小兒齒科學會 1992 大韓小兒齒科學會誌 Vol.19 No.2

Restorative method of congenital missing or traumatic loss of permanant teeth in children are very complicated. For the most cases, fabrication of porcelain fused metal bridge for a permanant tooth that was lost early in childhood is not the treatment of choice, because it involves much reduction of abutment teeth and so large pulp chambers can be easily esposed. Rather, temporary removable space maintainer with resin pontic or a restoration method, in which the first molar is banded and heavy wires is soldered and connected to anterior resin tooth, is used. Nevertheless, disadvantages such as patients discomfort, difficulty in care of appliance, and adverse periodontal effects, still exist. Since a restoration method that did not involve abutment reduction was introduced in 1970's etched cast restoration (so called "Maryland bridge") with increased strength and bond strength has been developed. Etched cast restoration has many advantages : it is favorable in appearance ; requiring only the slight refuction of abutment teeth lessens possibility of pulp exposure ; and supragingival margin allows maintanance of good gingival health. In these cases, satisfactory results were obtained from using etched cast restoration for treatment of 13.2-year-old boy with traumatic loss of maxillary left central incisor and 11.3-year-old girl with congenital missing of mandibular left central incisor.

Preventive Glass lonomer Restoration의 치험증례

이종갑,이주헌,손흥규,최병재 大韓小兒齒科學會 1993 大韓小兒齒科學會誌 Vol.20 No.2

The “preventive glass ionomer restoration ”was first described by Garcia-Godoy in 1986, which was a variation of the preventive resin restoration. The preventive glass ionomer restoration has disadvantages of low wear resistance, technique sensitive, and no long term clinical evaluation. However, it has advantages as mininal setting shrinkage, fluoride release, chemical bonding to dentin and enamel, coefficient of thermal expansion sinilar to that of tooth structure, and low pulpal toxicity. Therefore, applying this technique on low stress bearing area of initial carious lesion can be a good restorative method.

가성부갑상선기능저하증 환아의 구강내 증상에 관한 증례보고

이종갑,최병재,이제호,장지영 大韓小兒齒科學會 1999 大韓小兒齒科學會誌 Vol.26 No.3

부갑상선기능저하증은 혈장내 칼슘 농도에 반응해 분비되는 부갑상선 호르몬의 분비가 비정상적으로 감소된 상태를 의미한다.이에 반해 가성부갑상선기능저하증은 부갑상선의 기능은 정상이나 뇨세관과 파골세포등의 말단기관들이 부갑상선 호르몬에 반응하지 않는 질환이며,원인은 이들 호르몬이 결합하는 수용성 성분인 Guanin protein을 결정하는 GS gene의 돌연변이에 의한다. 부갑상선기능저하증은 평균8-9세에 발병하며 대부분이 20세 이전에 호발하게 되는데,이 질환에 이환된 경우 특징적으로 뇌,호르몬 기관,연골세포등에 존재하는 GS gene의 돌연변이로 인해 성장 및 발육부전,둥근 얼굴,비만,허리만곡증,외골증등이 생기며,조기 골단 폐쇄로 인한 중수골 및 중족골의 왜소증이 나타난다.그리고 공통적으로 갑상선 자극 호르몬,생식 호르몬,glucagon등의 다수 호르몬에 대해서도 반응하지 않는다. 이들의 치과적 특징은,법량질의 형성부전과 맹출 지연이 가장 일반적이고 치배의 무형성,치배결손,짧고 이형성된 치근과 넓어진 치수강,왜소치,치수내 석회화,부정교합 등도 자주 보고되고 있다. 가상부갑상선기능저하증으로 진단된 본 증례 환아의 구강내 소견으로는 전반적으로 짧고 미발육된 영구치 치근과 소구치 및 대구치의 맹출 지연과 미맹출,제 1,2 소구치와 제 2 대구치이 형성 부전양상이 보이고 있다. 이에 저자는 연세대학교 치과병원 소아치과에 내원한 가상부갑상선기능저하증 환자를 경험하였기에 문헌고찰과 함께 보고한는 바이다. Hypoparathyroidism has abnomally decreased secretion of parathyroid hormon which responds to the blood calcium level.Whereas, Pseudohypoparathyroidism has normal activity of thyroid hormon,but end-organs,such as uninary tract and osteocalst,do not respond to parathyroid hormon.The cause of this disease is due to the mutation of Guanine stimulating(Gs)protein regulating Gs gene,which is the receptor to this hormon. Pseudohypoparathyroidism is usually noted before 20 years old average of 8-9 years old.The clinical features of this disease includes delayed growth and development,round face,obesity,soft tissue calcification,ectopic ossification,shortening of metacarpals and metatarsals by epiphyseal closure in advance of age. The mutation of Gs gene which are found in brain,endocrine organs,and chondrocytes is the cause of those features. Reaction to Glucagon,gonadal hormon,and thyroid stimulating hormon is not expected in both cases. The common dental manifestations include enamel hypoplasia,delayed eruption,agenesis of tooth,hypodotia,dysplastic short roots,widened pulpal space,microdontia,intrapulpal calcification,and malocclusion are also often reported. This case which is diagnosed to Pseudohypoparathyroidism showed short and under developed root of permanent teeth,delayed eruption,and non-eruption of premolars and molars.And morphogenesis imperfecta of first and second premolars were also found.

Papilloma 에 관한 증례보고

이종갑,최병재,김종태,손흥규 大韓小兒齒科學會 1995 大韓小兒齒科學會誌 Vol.22 No.2

The squamous papilloma is a relatively common benign neoplasm that arises from the surface epithelium. It is typically an exophytic lesion whose surface may vary cauliflower-like to fingerlike in appearance, and while generally being a pedunculated lesion, it may arise from a sessile base. The most common sites of occurrence appear to be on the tongue and palatal complex, followed by the buccal mucosa, gingiva, and lips. It is also can be seen with some frequency on the alveolar ridge, floor of the mouth, and retromolar pad regions. Histologically, the papilloma is seen as a proliferation of the spinous cell layer in a papillary pattern often accompanies gyperkeratosis, acanthosis, and spinous cell layer in a papillary pattern often acconpanies hyperkeratosis, acanthosis, and basilar hyperplasia. Mitotic figures also may be prominent. The supporting fibrous connective-tissue stroma often contains prominent numbers of small blood vessels as well as an inflammatory cell infiltrate. The cause of papilloma is not well known, but suggested that chronic inflammatory irritation, mechanical irritation, and viral infection may be the causes. Recently association with papillomavirus is studied by morphological study, immuno-histochemistry, and DNA hybridization. These three cases were recovered by surgial excision without recurrence. By immunohistochemistry, Case 1 and Case 3 showed positive reaction to HPV antigen.