• 대한소아치과학회지
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• 제35권2호
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• pp.287-296
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• 2008

본 연구는 항우식 제품인 저농도의 불소 양치액(500 ppm NaF)과 Casein phosphopeptide-amorphous calcium phosphate(CPP-ACP)를 포함하는 치아 연고, 그리고 이 두 제품을 같이 사용했을 경우, 인공 우식 병소의 재광화 효과를 알아보고자 하였다. 제3대구치 협면에 인공우식을 유발하였고, 시편을 16개씩 4군으로 나누어, 28일 동안 매일 2 회 다음과 같은 항우식 제품을 시편에 처리하였고, pH 순환 시스템을 적용하였다. 1군: 대조군(무처치) 2군: Tooth $Mousse^{(R)}$ (GC Co. Japan) 3군: 치카치카$^{(R)}$ (삼일제약. 한국) 4군: 치카치카$^{(R)}$+Tooth Mousse$^{(R)}$ 무기질 소실량(${\Delta}Q$)의 장기적인 변화를 Quantitative light-induced fluorescence(QLF)를 이용하여 관찰하여 다음과 같은 결과를 얻었다. 1. ${\Delta}Q$는 1군에서는 28일동안 유의성 있는 차이를 보이지 않았고, 2군과 3군에서는 처치전에 비해 14일부터 유의성 있는 증가를 보였으며, 4군에서는 7일부터 유의성 있는 증가를 보였다. 2. ${\Delta}Q$는 1군 < 2군, 3군 < 4군 순이었다. 3. ${\Delta}Q$는 1군과 비교시 2군은 7일, 3군과 4군은 3일부터 유의성 있는 증가를 보였고, 2군은 3군과 전 기간 동안 유의차가 없었다. 4군은 2군과 3군에 비해 28일에 유의성 있는 증가를 보였다. 4. 모든 군에서 재광화 속도는 점차 감소하였다.

• 대한치과교정학회지
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• 제48권6호
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• pp.377-383
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• 2018

Objective: This study was performed to investigate the effects of external tooth bleaching with flouridation on the appearance of white spot lesions (WSLs) in vitro. Methods: In total, 125 bracket-bonded bovine incisor enamel blocks with artificial WSLs were randomly divided into a control group and four treatment groups (home bleaching, home bleaching + fluoridation, in-office bleaching, and in-office bleaching + fluoridation). A spectroradiometer (SR) and digital images (DIs) were used to evaluate colorimetric parameters (Commission Internationale l'Eclairage $L^*a^*b^*$) for all specimens. Color measurements were obtained before WSL formation (T1), after WSL formation (T2), and after completion of the external tooth bleaching treatment (T3). Results: The SRbased color change after bleaching was significantly greater in the treatment groups than in the control group (p < 0.05). SR-based lightness ($L^*$) and redgreen ($a^*$) values were significantly higher at T2 than at T1 (p < 0.001), with no significant changes in yellow-blue ($b^*$) values. At T3, SR-based $L^*$ values had increased while $a^*$ and $b^*$ values had decreased in the treatment groups (p < 0.001). The DI-based color difference between the sound enamel and WSL areas (DE*DI) increased significantly from T1 to T2 in all groups (p < 0.001) and significantly decreased from T2 to T3 in the treatment groups (p < 0.001). No significant differences in ${\Delta}E^*DI$ at T3 were shown between the four treatment groups (p > 0.05). Conclusions: The findings of this study suggested that external tooth bleaching with fluoridation can alleviate the conspicuity of WSLs.

• 대한구순구개열학회지
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• 제15권1호
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• pp.29-38
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• 2012

A 20 year-old cleft lip and palate patient came for occlusal rehabilitation, but the constricted maxilla and early loss of posterior teeth called for an unusual treatment modalities. Distraction osteogenesis in the edentulous areas followed by artificial bone graft, dental implant along with orthodontic tooth movement were planed. Multidisciplinary treatment enabled both esthetic and functional oral rehabilitation of this patient.

• 대한치과기공학회지
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• 제6권1호
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• pp.15-18
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• 1984

A denture that shifts easily in response to latterally applied forces can cause a disruption in the border seal or prevent the denture base from Correctly relating to the supporting tissue. The factors that Contribute to stability include ridge height and conformation, base adaptation, residual ridge relationships, occlusion harmony, and Muscle control. These factors can be condensed into the following categories; 1. The relationship of the denture base to the underlying tissue. 2. The relationship of occlusal harmony. 3. The relationship of the denture surface and border to the surrounding muscle. 4. The location of artificial tooth.

• 대한치과기공학회지
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• 제31권1호
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• pp.63-74
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• 2009

Partial or complete prosthesis is needed when teeth are lost due to various kinds of reason. Artificial teeth recover occlusion instead of natural teeth. Artificial teeth are required of esthetics, fragile resistance and abrasive resistance. Artificial tooth is made of acrylic resin or porcelain. Nowadays, acrylic resin artificial teeth are mainly used. Acrylic resin teeth are occluded with natural teeth, gold alloy, Ni-Cr alloy or porcelain etc. Acrylic resin teeth have similar translucency, gloss of natural teeth. And it has good chemical bond with denture base material, but it has low wear resistance. The aim of this study is to compare wear resistance among several denture teeth(Endura, SR-orthosit-PE, Planustar) and between artificial resin denture teeth and opposing 3 restorative materials(gold, Ni-Cr alloy, porcelain). Wear tests were conducted with a rotating wear testing apparatus(pin-on-disk type wear tester) under conditions of rpm 180, 75 minutes and constant loading of 50N. The upper part was the cusp of maxillary first molar and the lower part was a disk type restorative materials. To make similar oral environment, water was supplied continually. The acrylic resin teeth wear was determined by weighing the cusp each 5 minutes during 75 minutes test. Vicker's hardness tester was used to evaluate the surface hardness of test specimens. The SEM was used to evaluate the wear surfaces. The results were as follows: 1. Wear rates of acrylic resin teeth opposing to the restorative materials were high in order of Porcelain, Gold, Ni-Cr alloy (p<.05). 2. Wear resistance rate opposing to the Porcelain disk, was shown in order of Endura, SR-orthosit-PE, Planustar. The wear rate of opposing to porcelain disk was above two times more than that of other groups (p<.05). 3. Wear resistance rates opposing to the Gold, Ni-Cr alloy disk, was shown in order of Endura, SR-orthosit-PE, Planustar (p<.05). 4. A degree of the surface hardness is directly proportional to the degree of wear resistance. There are statistically significant differences between each groups (p<.05).

• KSBB Journal
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• 제8권2호
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• pp.126-132
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• 1993

The objective of this study was to develop an artificial dentin for easy handle and accurate observation of the mechanism on dental caries and to screen biologically active materials from the extracts of traditional plants and fruits for prevention of early dental cares. In order to produce disc PAHA (artificial dentin), the powdered hydroxylapatite was immobilized in a 20% polyacrylamide gel. The characteristics of disc PAHA was very similar to the surface, figure and lattice of human enamel. After decalcification in 0.1M citric acid based on observation with SEM. The critical point of decalcification of disc PAHA by acids was found to be pH 5.0-5.5, which was hi agreement with human enamel. The degree of decalcification from disc PAHA in 0.1M citric acid solution was sixfold higher than that of human enamel. This result suggested that disc PAHA would be useful as a substitute of human enamel for in vitro experiment. The extracts of garlic and Flower Apple A, B seemed to inhibit growth of S. mutans. Especially, when the 300$\mu\ell$ of its extracts added to the medium to incubate S. mutans, F. apple B showed strongly an inhibitory effect in both the growth of S. mutans and the synthesis of insoluble glucan.

• Journal of Biosystems Engineering
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• 제32권1호
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• pp.57-62
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• 2007

The objectives of this study were to prepare a new artificial eardrum patch using water-insoluble chitosan for healing the tympanic membrane perforations and to investigate biomechanical properties and cyotoxicity of the chitosan patch scaffold (CPS). Tensile strength and elongation at the rupture point of CPSs were 2.49-74.05 MPa and 0.11-107.06%, respectively. As the biomechanical properties or CPSs varied with the concentration of chitosan and glycerol, the proper conditions for the CPS were found out. SEM analysis showed very smooth and uniform surface of CPSs without pores at x1000. The result of MTT test showed that CPSs had no cytotoxicity.

• 한국동물위생학회지
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• 제30권3호
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• pp.459-466
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• 2007

The Korean Musk deer (Moschus Moschiferus) is endangered due to heavy hunting and Massive destructions of natural habitat. They are included in CITES appendix II. In addition they are designated as a precious natural product in 1968 and listed as endangered species by the Government and Cultural Heritage Administration. At present, the number of musk deer in Korea is smaller than minimum viable population. Without increment of the population size, natural restoration is impossible. It is necessary to develop the artificial growth and re-enforcement methods in order to conservation Korean musk deer. Furthermore, It is necessary to ensure that we have an adequate individual group for artificial growth and re-enforcement. To ensure that we have an adequate individual group, it is necessary to know ecology of musk deer. This study is conducted to confirm and investigate of habitat of musk deer in order to capture individual musk deer. we investigated, confirmed habitats, found traces and captured using trap and decoy. Captured musk deer is male and 5.5 kg, this have canine tooth of 1.5cm, is estimated 15 months old. After capture, we measured each parts of body and tested to research of parasite infection. Strongyloides papillous was founded in the feces. It is essential to get healthy individual and establish of artificial growth technique.

• 한국산업융합학회 논문집
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• 제25권2_2호
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• pp.309-314
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• 2022

The bonding strength [ISO22674] test was conducted by firing a dedicated ceramic powder on the surface of the dental titanium material treated with micro-arc oxidation. In the test group, an average result value of 34.34 MPa was obtained, and in the control group, a result value of 21.53 MPa was obtained. The bonding strength of the test group was higher than that of the control group by 12.81 MPa, resulting in a 37% improvement in durability of the dental artificial tooth ceramic restoration.

• 대한기계학회논문집B
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• 제40권5호
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• pp.305-311
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• 2016

유도가열은 유도전류를 이용하여 도체에 열을 가하는 방식이다. 유도가열은 열을 가하고자 하는 물체 내부에서 열이 발생하고, 비접촉이며 안전하기 때문에 산업이나 의료분야에서 광범위하게 사용되고 있다. 최근에 형상기억합금을 사용하여 열에 의해 인공치아가 임플란트에서 쉽게 빠질 수 있게 하는 임플란트 시스템이 개발되었다. 본 논문에서는 새로운 임플란트 시스템에서 인공치아를 쉽게 제거할 수 있는 유도가열 장치를 개발하였다. 먼저 전자장-열 구조 유한요소 연성 해석을 통해 다양한 입력 전류와 코일 형상에 대해 온도를 시뮬레이션 상으로 확인해보았다. 해석 결과를 토대로 유도가열장치 시작품을 제작하여 실험을 통해 86초에 인공 치아가 분리됨을 확인하였다.