• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.123-125
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• 2008

Enamel layer consists of carbonated hydroxyapatite of 85%, water of 12% and protein of 3% and lipid and tentin consists of carbonated hydroxyapatite of 47%, water of 20% and protein of 33% and lipid so if heat is increased in teeth and then teeth color is discolor. In case high temperature is applied in teeth, teeth color changed quality is measured about change of time for minimize teeth change of color. Spectroscopic light intensity special quality by change of time rise at specification temperature.

• Journal of Oral Medicine and Pain
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• v.15 no.1
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• pp.45-53
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• 1991

저자는 두개하악 장애로 교합상치료를 받고있는 42명의 환자를 대상으로 치료전, 치료후 1개월, 3개월, 6개월째에 주관적 평가, 임상적 검사, 근전도 검사, 컴퓨터 교합 분석을 시행하여 다음과 같은 결론을 얻었다. 1. 주관적 평가인 visual analogue scale과 Helkimo's anamnestic dysfunction index는 유의하게 감소하였다. 임상적 검사시 MM(mandibular movement), TM(TMJ capsule palpation), EM(extraoral muscle palpation), Di(Helkimo's clinical dysfuction index)는 유의하게 감소하였고 무통성 개구량은 유의하게 감소하였다. 2. 42명의 환자중 10명에서 교합변화가 관찰되었으며, 5명에서 치주질환, 2명에서 치아 과민감, 1명에서 구토경향이 관찰되었다. 3. 치주칠환을 보이는 10명의 환자중 3명은 교합상치료 이전부터 치주질환에 이환된 상태였으며 3명에서는 교합변화가 함께 관찰되었다. 4. 교합변화를 보인 10명의 환자중 교합상의 장착시간을 줄였을 때, 3명이 원래의 교합상태로 회복되었고 4명은 부분적으로 회복되었으며 3명에서는 변화를 관찰할 수 없었다. 5. 악관절 내장 제 5기 환자에서 교합변화가 더 빈번히 나타났으며 통계적으로 유의한 차이를 보였다. 6. Habitual clenching 시와 Maximal clenching 시 사이의 치아접촉점 수, maximal clenching 시의 치아 접촉점의 수와 접촉 치아수 사이에 매우 유의한 상관관계를 보였고, habitual clenching 시의 치아접촉점의 수와 접촉 치아수, Habitual clenching 시와 maximal clenching시 사이의 치아 접촉시간에서도 유의한 상관관계를 보였다.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.2
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• pp.7-13
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• 1997

조직학적으로 유용성이 입증된 산탈회법을 이용한 인접면 비교적 초기 치아 우식의 병소를 형성하여 진단율을 조사하였다. 산 용액을 이용하여 20개 인접면 치아우식을 20개 소구치에 형성하였고, 37개 인접면 치아우식을 30개 대구치에 형성하였다. 건전한 소구치 20개, 대구치 30개를 포함하여 총 96개 치아를 4개씩 나누어 24개의 블록을 형성하였고, 각각 2개 블록의 교합면을 교합시켜서, 교익촬영을 하였다. 촬영 결과를 36명의 치과의사들이인접면 치아우식의 유무를 기록하고, 동시에 및 ROC 분석을 위한 5 개 범주의 판독 기준으로 판독하여 기록하였다. 인접면 치아우식증 유, 무만으로 판독한 결과 진단의 sensitivity는 0.71, specificity는 0.78 이였다. ROC 분석 한 결과의 곡선도표 아래부분의 평균 면적은 약 0.806 이였다. 치아우식증 유무만으로 진단한 결과는 특정한 sensitivity와 specificity 만을 나타내지만, ROC 분석 결과는 주관적 진단 기준과 구별되는 고유의 진단 능력을 표시하는 1-specificity(False Positive)의 변화에 따른 sensitivity(True Positive)의 변화를 연속적으로 나타내어 주었다.

• The Journal of the Korean dental association
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• v.25 no.10 s.221
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• pp.913-916
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• 1987

저작운동을 중추신경계와 말초조직의 작용에의해 일생동안 학습과 적응의 가정을 통해 이루어진다. 저작의 양상은 유치가 구강내에 맹출되면서 이루어지며, 상하악 치아의 접촉, 점막과 혀 및 치아상호간에 일어나는 접촉과 치근막의 고유수용기와 악관절 수용기등에 의해 조정되어 최종적으로 에너지소비가 적고 동통이나 불편함이 없이 최대의 효율을 나타내는 양상으로 된다. 그러나 원활한 저작과 하악은동을 이룩하기 위해서는 저작근, 악관절, 상하악 치아의 교합등이 서로 조화를 이루어야 한다. 만일 외상에 의해 악관절의 기능장애가 오면 저작근활동이 변화하고 이에따라 교합장애를 야기한다. 또한 치아를 상실하거나 대합치아간의 조기접촉이 있으면 교합장애가 원인이 되어 근육활동이 변화와 악관절 기능장애를 초래한다. 그리고 때로는 지나친 근육의 활동(이갈이, 지속적 긴장성 수축)에 의해 지나친 치아의 마모로인한 교합장애나 악관절장애를 일으킬 수 있다. 따라서 하악의 기능을 충분히 이해하기 위해서는 교합의 형태학적 관계와 더불어 저작계의 기능적인 면도 고려하여 그 상호관계를 검토하여야 하며 본문에서는 교합에 관련된 저작근의 작용과 이에 영향을 주는 요인 및 교합장애와 근육활동장애의 연관성에 관해 고찰코자 한다.

• The korean journal of orthodontics
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• v.37 no.2 s.121
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• pp.114-124
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• 2007

Objective: The purpose of this study was to examine how the mesio-distal angulation and the length of each tooth changes on panoramic radiograph at different bucco-lingual inclinations. Methods: After constructing an acrylic model based on the mean arch of 30 adults with normal occlusion, the wire was placed in the center of the teeth on the acrylic model. First, the wire was implanted in normal angulation and inclination and a panoramic radiograph taken. After changing the inclination from $I-5^{\circ}\;to\;I+15^{\circ}\;by\;5^{\circ}$, a panoramic radiograph was taken again and the mesio-distal angle and wire length on the panoramic radiograph were assessed. Results: When the wire was implanted at the normal angulation and inclination, the length measured in the panoramic radiograph was magnified $111{\sim}117%$ from the original length in the anterior region and $121{\sim}125%$ in the posterior region. Only the central and lateral incisors showed significant length differences when the inclination was changed from $l-15^{\circ}\;to\;I+15^{\circ}$ at fixed angulation. When the inclination was changed from $l-15^{\circ}\;to\;I+15^{\circ}$, the angulation of most teeth on panoramic radiograph appeared to be more disto-angulated than in reality, and the lateral incisor and canine showed the largest difference. Only $l-15^{\circ}\;to\;I+15^{\circ}$ groups of premolars and $I+15^{\circ}$ group of molars showed more mesio-angulation than in reality. As the labio(bucco)lingual inclination of all teeth were decreased, tooth angulation in the panoramic radiograph appeared to be more disto-angulated. Conclusion: The labio-liugual inclination of teeth should be considered because it affects panoramic image of teeth, such as length of incisors and angulation of other teeth.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.373-384
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• 2003

The purpose of this study was to evaluate the eruption pattern of a cyst-associated mandibular premolar after marsupialization of a dentigerous cyst in children. The result from the twenty two pairs of normalized panoramic radiographs of twenty two patients who underwent neither extraction nor orthodontic traction of the cyst-associated mandibular after marsupialization were as follows. 1. The eruption speed of a cyst-associated premolar was 3.5 times faster than that of the normal contra-lateral premolar(p<0.05). The angulation change of test group was an average of $2.7^{\circ}$ per month. 2. In the change of the level of root formation, the group which had a little root maturity tended to be faster in the eruption speed(p>0.05) and the R1/4 group had a great change in the angulation change(p>0.05). 3. In the change to be with the cusp position index, the eruption speeds were increased to the 30% deviation groups. But, the eruption speed was decreased above that(p>0.05). 4. Group with cyst diminishment rate of more than $80mm^2$ per month showed the fastest eruption speed of all(p<0.05). 5. The mesial angulated teeth in the test group were decreased more rapidly than the distal angulated teeth in the eruption speed(p>0.05). But, increased in the angulation change(p<0.05). 6. There was a tendency of faster tooth eruption with less deviation of tooth axis. Group with tooth axis deviation of less than $15^{\circ}$ showed the fastest angulation change of all(p<0.05). 7. The eruption speed and the angulation change rapidly decreased during the first 6 months following marsupialization. Based on the results of this study, a cyst-associated mandibular premolar erupted more rapidly after marsupializaton. We thought so that it's prognosis was good if the tooth had a little root maturity, a little devitation and cyst lesion healed faster. We recommend that if there is enough space for eruption, orthodontic traction and surgical treatment of the cyst-associated tooth should be postponed 6 months after marsupialization.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.423-430
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• 2003

The teeth bleaching with bleaching agent is widely used at recent times. Until yet the exact mechanism of the bleaching agent isn't known but it is thought that is by the complex reduction-oxidation reaction of the decomposed free radical from bleaching agent through various ways. In other words, it is supposed that the teeth are whitened by agent's changing chemical structures of stain-causing materials. The purpose of this study is to exam the change of the dentinal character by bleaching agent and to evaluate the safety of this agent. For this study, after applying 10% carbamide peroxide to enamel of human premolar for 6 hours a day for 2 weeks we examined changes of surface morphology, microhardness, composition and contents of minirals in human dentin using SEM, microhardness tester, FT-Raman spectrometer and EPMA and got following results. There was no significant difference in surface morphologic change when we examined the effect of 10% carbamide peroxide which penetrated into dentin after applied on enamel surface comparing with result from specimen in distilled water No change was shown on the surface of peritubular and intertubular dentin within the nanometeric range. The microhardness between bleached teeth and teeth stored in distilled water showed no statistically significant difference FT-Raman spectra of dentin exhibited no change of the component in human dentin. Only the least change in peaks of organic and inorganic materials were detected in Raman intencity. The total content of mineral elements in dentin with no treatment, stored only in distilled water and stored in distilled water after bleaching were $98.73{\pm}1.89,\;98.56{\pm}2.11\;and\;97.47{\pm}2.51$ respectively. Also they showed no statistically significant difference. From above results, the effect of 10% carbamide peroxide bleaching on structure of dentin is very low and the results may confirm the safety of this bleaching agent.

• The Journal of the Korea Contents Association
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• v.13 no.10
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• pp.427-433
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• 2013

The aim of this study was to evaluate the efficacy of bleached tooth with white toothpaste on the whitening effect, microhardness test. Forty-four human interior teeth were randomly assigned to two groups as follows: Group 1 was used general toothpaste as control, Group 2 exposed to white toothpaste at 3 times a day for 3 minutes. The total application time was 4 weeks. After each application, all tooth were washed with distilled water and immersed in artificial saliva. The color change and microhardness were measured using CIELab Color system and microhardness tester. The data were analyzed by student t-test, using SPSS 20.0 statistical computer program (SPSS Inc., USA). The overall color changes (${\Delta}E$) by white toothpaste have a capability of the whitening efficacy by factor of 2.3 times larger compared with general toothpaste. Moreover, the application of white toothpaste did not cause any microhardness reduction on enamel surface.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.664-676
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• 1996

테트라싸이클린에 의한 치아 변색은 심미성을 고려한 임상 치료시 커다란 난제로 남아 있다. 본 연구는 백서 치아에 테트라싸이클린을 주입하여 야기되는 색상과 구조적인 변화도를 측정하여 향후 연구에 기초자료를 제공하기 위해 시행되었다. 24 마리의 백서를 각기 8 마리씩 3 군으로 분류하여 대조군은 정상적인 사육을 식염수군은 TC군과 동량의 식염수를 주사하였으며 TC군은 12 ml에 용해시킨 60 mg의 테트라싸이클린을 복강내로 2 주간 주입하였다. 최종 주입후 1 주간 정상 사육한 다음 cervical dislocation법에 의해 희생시켜 시편을 채득한 후 각 치아를 횡단하여 실물현미경과 FlexCam을 이용하여 컴퓨터에 영상을 저장한 다음 색 변화량을 Adobe Photoshop으로 측정하였으며 구조변화는 주사전자 현미경을 이용하였다. 치아색 변화량의 유의성 검정은 ANOVA와 Scheffe test를 이용하였으며 본 실험 결과는 다음과 같다. 1. 각 군의 $a^*$ 수치는 대조군 -6.12 (1.18), 식염수군 -8.00 (1.33), TC군 -18.56 (2.52)로 나타났으며 $b^*$ 수치는 대조군 1.12 (2.13), 식염수군 1.62 (1.45), TC군 28.67 (5.18)을 보였다. 즉 테트라싸이클린에 의해 $a^*$와 $b^*$의 수치가 유의성있게 (p<0.01) 초록색과 노란색 방향으로 변화하였다. 2. 테트라싸이클린에 의해 치경부 법랑질 외면이 검게 변색되었으며 울퉁불퉁한 양태로 변화되었다. 그러나 법랑소주의 형태, 방향등은 차이를 보이지 않았다. 3. 각 군간 상아세관의 수, 방향, 크기등이 차이가 없었다. 치수측에서의 관찰결과 대조군과 식염수군에서는 상아세관들의 입구가 크고 명확하게 보인 반면 TC군에서는 입구가 좁고 부분적으로 막힌 양태도 관찰되었다.

• The korean journal of orthodontics
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• v.27 no.3 s.62
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• pp.421-430
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• 1997

Alveolar bone grows with development of tooth germs and roots; bone deposition occurs with tooth eruption. Bone components undergoes processes of resorption and deposition, and when the balance between them is disrupted, decrease in alveolar bone height or excessive bone deposition result. It has been hon that repositioning of teeth through orthodontic treatment can cause alveolar bone resorption which result in decreased alveolar bone height, and there have been many studies to evaluate such effects. X-ray films that could be replicated and standardized were chosen in clinical studies, and among them, bitewing films were used for objective evaluation of changes in alveolar bone level. Twenty subjects, 10 to 13-year- old (average 12.2) children with Cl I molar key, healthy oral condition, no congenital missing, no periodontal disease, and pre-and post-orthodontic bitewing films, were randomly selected for comparison of alveolar bone heights. Amounts of tooth and changes in alveolar bone heights were analyzed. The following results were obtained: 1. Amount of tooth movement in canine, premolar, and molar regions, changes in tooth axis, and changes in alveolar bone heights were measured, and the mean and median values were obtained. 2. When pre-and post-orthodontic alveolar bone levels were compared, larger changes were noticed in maxilla than mandible. 3. When mesio-distally compared, larger changes were observed in the distal sides of 3D3 and 4M3, mesial sides of 4M3 and 4D3, distal sides of 4D3 and 5M3, mesial sides of 5M3 and 5D3, md distal sides of 5D3 and 6M3. 4. When the amounts of tooth movements(TX, TY)and changes in tooth axis(A) were compared,34TX, 34TY, 34A of both sides in maxilla were greater, iud changes in alveolar bone level were greater than any other region.