• 한국치위생학회지
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• 제12권4호
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• pp.733-739
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• 2012

Objectives : To Compare the degree of survival rate of gingival fibroblasts, which is concerned with teeth adherence based on the type of avulsed tooth's storage solution. Methods : Different media gingival fibroblasts were stored in Dulbecco's modified Eagle's medium(DMEM), Hank's balanced salt solution(HBSS), milk, saline, and green tea in for 1, 2, 3 hours. And, MTT assay was conducted to compare survival rate of human gingival fibroblasts. Results : 1. The survival rate of gingival fibroblasts in DMEM and HBSS was higher than thoes in other storage media( Milk> Saline> Green tea). 2. The survival rate of gingival fibroblasts in milk, saline and green tea decreased as time passed. 3. Because of low osmotic pressure, green tea showed decrease of survival rate of gingival fibroblasts. Conclusion : DMEM and HBSS were the most effective storage media for gingival fibroblast. Among milk, saline, green tea, milk is most effective storage media for keeping gingival fibroblasts. Milk is recommended for storage media of avulsed tooth for keeping viability of cells.

• 대한치과보철학회지
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• 제40권2호
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• pp.172-183
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• 2002

This study is going to compare the degree of color change which occurs in the following two cases of the factors which cause the color change of extra-staining, one is during glazing by the dental technician, the other is tooth brush abrasion which makes the biggest influence on color change. To compare the degree of color change before and after glazing, a sample was made with vintage incisal porcelain No. 59 OPAL(Shofu Inc, Japan), after that it was painted with three colors of porcelain stainers, then the degree of color was measured with a spectrophometer(Model Chromaview 300, Spectoron Tech Co. Korea) after it had been treated with firing only and glazing after firing 40,000-cycle and 80,000-cycle of tooth brush abrasion test were carried out in order to simulate the brushing effect of 4 years and 8 years by using the abrasion tester. The colors were measured before the test, and after the 40,000-cycle and 80.000-cycle operations and the surfaces were examined by SEM. The results of this study were as follows ; 1. The color change before and after glazing was not great enough to have a clinical significance but the orange color was changed more significantly statistically than the blue and light brown(p<0.05). 2. In the case of the color change of stained porcelain by tooth brushing, carrying out staining and glazing with two-times firings resulted in statically less color change than one firing only(p<0.05). 3. In the case of the difference in the stainer's color, the orange color which has higher chroma was statically more sensitive than the blue color(p<0.05) 4. In the case of the color change after the 80,000-cycle abrasion, all showed color change when there was one firing and the orange stainer showed some color change with clinical significance when firings were done two times.

• 대한치과교정학회지
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• 제30권1호
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• pp.9-17
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• 2000

본 연구는 발치 후 인접치 이동을 위한 교정력 적용 시 적용 시기에 따른 치아이동 양상을 비교$\cdot$분석하기 위하여 시행되었다. 성견을 실험대상으로 상악 좌우 제 3절치를 3주 간격으로 각각 발거 하고, 양 견치 를 고정 원으로 제 2절치의 치체이동을 위한 장치를 장착하였다. 100 gm의 지속적인 힘을 내는 견인 스프링을 사용하여 발치 후 4주와 1주부터 좌우 제 2절치를 각각 12주간 동시에 견인하였다. 2주 간격으로 디지털 캘리퍼스를 이용하여 이동거리를 측정$\cdot$비교하고 실험에 사용된 좌우 제 2절치의 조직소견을 관찰하여 다음과 같은 결론을 얻었다. 1. 교정력 적용 후 처음 2주간에는 발치 후 4주에 견인한 치아가, 그 다음 2주간에는 발치 후 1주에 견인한 치아가 빠르게 이동하는 양상을 보였다. 2. 12주간의 실험기간 동안 견인 4주와 6주 사이에 가장 빠르게 이동하는 경향을, 이 후에는 이동 속도가 감소하는 양상을 보였다. 3. 실험기간 동안 이동한 전체 거리는 발치 후 4주에 비해 1주에 견인한 경우에서 크게 나타나는 경향을 보였다. 4. 발치 후 4주에 견인한 경우에 비하여 1주에 견인한 경우에서 유해한 조직소견이 나타나지 않았다. 이상의 결과는 발치 후 교정력 부여 시 조기 적용이 유리함을 시사하였다.

• 한국산학기술학회논문지
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• 제10권12호
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• pp.3895-3901
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• 2009

본 연구는 전문가치면세정술 및 구강보건교육이 구강청결도와 구강보건행태에 미치는 영향을 검증하는데 목적이 있다. 연구는 교육 군별 교육효과를 비교하기 위해 대조군 (80명-구강보건교육), 실험군 (80명-구강보건교육과 전문가치면세정술)으로 분류하여 진행하였다. 잇솔질 횟수, 잇솔질 시간, 점심식사 후 잇솔질 실천율, 구강위생용품 사용률, 구강청결도의 변화를 각 교육 군별로 비교 분석한 결과는 다음과 같다. 잇솔질 횟수의 변화는 두 교육군 모두 증가하였으나 개별전문가치면세정술과 구강보건교육을 시행한 실험군에서만 통계학적으로 유의한 행태변화를 나타냈다. 점심 식사 후 잇솔질 실천율의 변화는 두 교육 군 모두 증가하였으나 개별전문가치면세정술과 구강보건교육을 시행한 실험군의 증가가 더 높았고, 구강청결도의 점수는 대조군보다 실험군에서 더 높게 조사되었다.

• 구강회복응용과학지
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• 제26권3호
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• pp.265-271
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• 2010

심미적 보철물을 제작하는 데 있어 색조의 선택은 중요한 단계이다. 이러한 색조선택과정은 광원, 표면, 관찰자 의 능력, 주변 배경색상, 관찰각도, 명암적응력 등과 같은 다양한 원인에 의해 좌우된다. 색조를 선택하는 시점에 따라 치아의 건조정도는 달라지게 되므로 본 실험에서는 치아 건조정도가 자연치아의 색조에 미치는 영향에 대해 살펴보고자 하였다. 구강내 색조측정기를 이용하여 구강가글 즉시 측정한 군을 실험군으로 구강가글 10초 후, 1분 후, 5분 후, 30초간 건조 후 색조를 측정하여 ${\Delta}E$값을 비교하였다. 각 실험군사이 ${\Delta}E$값은 유의할 만한 차이를 보였으나 대부분의 경우 구강내에서 시각적으로 구별할 수 없는 정도의 근접치를 보였다. 실험결과 시각적인 방법으로 색조 견본을 이용하는 방법은 건조정도에 따른 색조 차이가 없는 것으로 사료되고 기계를 이용하는 경우 건조정도가 색조 선택에 유의할 만한 영향을 줄 것이라고 사료된다.

• 대한치과보철학회지
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• 제28권2호
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• pp.77-90
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• 1990

The purpose of this study was to compare the amount of the vertical pin opening of $33^{\circ}$ resin and $0^{\circ}$ resin teeth during processing and to determine whether the changes in tooth contacts by using articulation ribbon and T-Scan system follow any identifiable pattern, and to determine if there is any correlation between the changes in tooth contacts and the amount of the vertical pin opening after processing. Through statistical analyses on the data from this study, the following conclusions were obtained. 1. The amounts of the vertical pin opening were 0.78m, 0.87mm for $0^{\circ}$ teeth and $33^{\circ}$ teeth, respectively. But there was no significant difference between them. 2. The total number of contact points recorded by articulating ribbon after processing was decreased to 442.5% of that before processing. 3. The mean values for the number of contact points per tooth recorded by articulating ribbon after processing were 4.3 for the second molar, 3.8 for the first molar, 1.3 for the second premolar, 0.8 for the first premolar. The reduction of contact points per tooth became greater moving in an anterior direction. 4. The correlation between the reduction of contact points and the amount of the pin opening after processing was not significant. 5. The mean values for the numbers of contact points per tooth recorded by T-Scan system after processing were 2.2, 2.5, 1.0, and 0.5 at the second molar, the first molar, the second premolar, and the first premolar, respectively. 6. The correlation between the number of contact points by using articulating ribbon and TScan system after processing was not significant.

• The Journal of Advanced Prosthodontics
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• 제10권4호
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• pp.286-290
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• 2018

PURPOSE. Conventional resin-bonded fixed partial dentures (RBFPDs) are usually made with a two-retainer design. Unlike conventional RBFPDs, cantilever resin-bonded fixed partial dentures (Cantilever RBFPDs) are, for their part, made with a single-retainer design. The aim of this study was to compare the effect of tooth surface preparation on the bond strength of zirconia cantilever single-retainer RBFPDs. The objective is to evaluate the shear bond strength of these single-retainer RBFPDs bonded on 3 different amount of tooth surface preparation. MATERIALS AND METHODS. Thirty extracted bovine incisors were categorized to 3 groups (n=10), with different amounts of tooth surface preparations. Teeth were restored with single-retainer RBFPDs with different retainer surfaces: large retainer of $32mm^2$; medium retainer of $22mm^2$; no retainer and only a proximal connecting box of $12mm^2$. All RBFPDs were made of zirconia and were bonded using an adhesive system without adhesive capacity. Shear forces were applied to these restorations until debonding. RESULTS. Mean shear bond strength values for the groups I, II, and II were $2.39{\pm}0.53MPa$, $3.13{\pm}0.69MPa$, and $5.40{\pm}0.96MPa$, respectively. Statistical analyses were performed using a one-way ANOVA test with Bonferroni post-hoc test, at a significance level of 0.001. Failure modes were observed and showed a 100% adhesive fracture. CONCLUSION. It can be concluded that the preparation of large tooth surface preparation might be irrelevant. For zirconia single-retainer RBFPD, only the preparation of a proximal connecting box seems to be a reliable and minimally invasive approach. The differences are statistically significant.

• The Journal of Advanced Prosthodontics
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• 제3권3호
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• pp.166-171
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• 2011

PURPOSE. The purpose of this study is to evaluate and compare the shear bond strength of the gingiva-colored composite resin and the tooth-colored composite resin to porcelain, metal and zirconia. MATERIALS AND METHODS. Sixty cylindrical specimens were fabricated and divided into the following 6 groups (Group 1-W: tooth-colored composite bonded to porcelain, Group 1-P: gingiva-colored composite bonded to porcelain, Group 2-W: tooth-colored composite bonded to base metal, Group 2-P: gingiva-colored composite bonded to base metal, Group 3-W: tooth-colored composite bonded to zirconia, Group 3-P: gingiva-colored composite bonded to zirconia). The shear bond strength was measured with a universal testing machine after thermocycling and the failure mode was noted. All data were analyzed using the two-way analysis of variance test and the Bonferroni post-hoc test at a significance level of 0.05. RESULTS. The mean shear bond strength values in MPa were 12.39, 13.42, 8.78, 7.98, 4.64 and 3.74 for Group 1-W, 1-P, 2-W, 2-P, 3-W and 3-P, respectively. The difference between the two kinds of composite resin was not significant. The shear bond strength of Group 1 was the highest and that of Group 3 was the lowest. The differences among Group 1, 2 and 3 were all significant (P<.05). CONCLUSION. The shear bond strength of the gingiva-colored composite was not less than that of the tooth-colored composite. Thus, repairing or fabricating ceramic restorations using the gingiva-colored composite resin can be regarded as a practical method. Especially, the prognosis would be fine when applied on porcelain surfaces.

• Journal of Periodontal and Implant Science
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• 제40권4호
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• pp.188-193
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• 2010

Purpose: The aim of this study is to assess the influence exerted by the observer's dental specialization and compare patients' opinion with observers' opinion of the esthetics of maxillary single-tooth implants in the esthetic zone. Methods: Forty-one adult patients, who were treated with a single implant in the esthetic zone, were enrolled in this study. Eight observers (2 periodontists, 2 prosthodontists, 2 orthodontists and 2 senior dental students) applied the pink esthetic score (PES)/white esthetic score (WES) to 41 implant-supported single restorations twice with an interval of 4 weeks. We used a visual analog scale (VAS) to assess the patient's satisfaction with the treatment outcome from an esthetic point of view. Results: In the PES/WES, very good and moderate intraobserver agreements were noted between the first and second rating. The mean total PES/WES was $11.19{\pm}3.59$. The mean PES was $5.17{\pm}2.29$ and mean WES was $6.02{\pm}1.96$. In the total PES/WES, the difference between the groups was not significant. However, in the WES, the difference between the groups was significant and prosthodontists were found to have assigned poorer ratings than the other groups. Periodontists gave higher ratings than prosthodontists and senior dental students. Orthodontists were clearly more critical than the other observers. The statistical analysis revealed statistically significant correlation between patients' esthetic perception and dentists' perception of the anterior tooth. However, the correlation between the total PES/WES and the VAS score for the first premolar was not statistically significant. Conclusions: The PES/WES is an objective tool in rating the esthetics of implant supported single crowns and adjacent soft tissues. Orthodontists were the most critical observers, while periodontists were more generous than other observers. The statistical analysis revealed a statistically significant correlation between patients' esthetic perception and dentists' perception of the anterior tooth.

• 한국임상수의학회지
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• 제27권1호
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• pp.55-61
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• 2010

Tooth restoration with implant placement have been interested in modern veterinary dentistry. It is important to reduce the interval between the tooth extraction and the insertion of the implants, to determine the restoration time after implant placement in dogs The aim of the this study was to compare the bone mineral apposition rate of immediately loaded implants with an unloaded control during the early healing state in the artificial extraction mandible. In four Beagles, two premolar sockets (PM2 and PM3) of the both sides of the mandible were installed with a one stage titanium mini-implant with a length of 11 mm and a diameter of 3.37 mm immediately after tooth extraction. Provisional restroration was given to implants, 3 weeks after implant placement in the left side (immediate loading) and 12 weeks in the right side (delayed loading), respectively. Radiographic and histologic examinations were performed. Radiographic evaluation revealed no significant difference between two groups. Bone-implant contact was $47.1{\pm}8.9$ in immediate loading and $50.2{\pm}8.2$ in delayed loading, interthread bone density was $78.7{\pm}10.9$ in immediate loading and $73.1{\pm}15.5$ in delayed loading, and peri-implant bone density was $95.4{\pm}7.1$ in immediate loading and $95.0{\pm}5.2$ in delayed loading, respectively. Three histologic analyses showed no significant difference between delayed and immediate loading. Followed by this study, the immediate loading of implants insterted into fresh extraction sockets after tooth extraction could be considered in veterinary dentistry.