• 대한치과보철학회지
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• 제44권4호
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• pp.466-476
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• 2006

Purpose : Colonization of denture soft lining materials by Candida albicans can result in clinical problem, and deterioration of the materials. This study aimed to compare the retention and penetration of C. albicans into four denture soft lining materials commonly used. Materials and methods : Four denture soft lining materials (Coe-comfort$^{(R)}$, Coe-soft$^{(R)}$, GC soft liner$^{(R)}$, and Tissue conditioner$^{(R)}$) discs were prepared to glass slide and dental stone. Adherence of yeast to surfaces was monitored after one hour incubation of standardized washed cell suspension with test disc surfaces. Adherent cells stained with acridine orange were counted fluorescence microscopy. Penetration of yeast into materials bonded with acrylic resin after 1, 2, 3,4, 5, 6 and 7 days incubation was observed through sections stained using acridine orange and estimated to quantitative analysis using radioisotope. Results : There was statistical significance in cell numbers between smooth and rough surfaces(p<0.05). Higher numbers of cells were observed on rough surfaces. There was statistical significance in adherent cell numbers into smooth and rough surfaces individually(p<0.05). According to the increase of incubation periods, the cells penetrated into denture soft lining materials were shown to increase. The differences among all kinds of soft liner were statistically significant(p<0.05),and the largest number of cells penetrated into soft liners was observed in the Coe-soft$^{(R)}$. Conclusion : Initial adherence and penetration of yeast into denture soft lining materials has been influenced by surface roughness and chemical composition of them. The selection of appropriate materials and their fabrication may promote clinical performance.

• The Journal of Advanced Prosthodontics
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• 제14권5호
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• pp.305-314
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• 2022

PURPOSE. The aim of this study was to evaluate the flexural strength of a 3D-printed denture base resin (Cosmos Denture), after different immediate repair techniques with surface treatments and thermocycling. MATERIALS AND METHODS. Rectangular 3D-printed denture base resin (Cosmos Denture) specimens (N = 130) were thermocycled (5,000 cycles, 5℃ and 55℃) before and after the different repair techniques (n = 10 per group) using an autopolymerized acrylic resin (Jet, J) or a hard relining resin (Soft Confort, SC), and different surface treatments: Jet resin monomer for 180 s (MMA), blasting with aluminum oxide (JAT) or erbium: yttrium-aluminum-garnet laser (L). The control group were intact specimens. A three-point flexural strength test was performed, and data (MPa) were analyzed by ANOVA and Games-Howell post hoc test (α = 0.05). Each failure was observed and classified through stereomicroscope images and the surface treatments were viewed by scanning electron microscope (SEM). RESULTS. Control group showed the highest mean of flexural strength, statistically different from the other groups (P < .001), followed by MMA+J group. The groups with L treatment were statistically similar to the MMA groups (P > .05). The JAT+J group was better than the SC and JAT+SC groups (P < .05), but similar to the other groups (P > .05). Adhesive failures were most observed in JAT groups, especially when repaired with SC. The SEM images showed surface changes for all treatments, except JAT alone. CONCLUSION. Denture bases fabricated with 3D-printed resin should be preferably repaired with MMA+J. SC and JAT+SC showed the worst results. Blasting impaired the adhesion of the SC resin.

• 대한소아치과학회지
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• 제32권2호
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• pp.332-343
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• 2005

본 연구에서는 기존의 할로겐 광중합기를 이용하여 40초간 조사하여 복합레진을 중합한 경우와 플라즈마 광중합기를 이용한 고강도의 중합 및 완속기시 중합 방식, 그리고 LED 광중합기를 이용한 통법의 중합과 완속기시 중합 방식으로 복합레진을 중합하여 발생되는 수축응력을 비교하고 미세경도를 측정하여 중합도를 평가하였다. 내경 7mm, 외경 10mrn의 아크릴릭 주형을 제작하고 외면에 스트레인게이지를 부착시킨 뒤 각각의 광원에 따른 중합모드로 광중합 하였다. 광조사 시점부터 1초 간격으로 600초간 수축응력을 측정하였으며, 중합 24시간 후 각 군의 미세경도를 측정하여 통계 분석하였다. 수축응력 측정 후 시편을 종단하여 주사전자현미경으로 레진수복물과 아크릴릭 주형 계면을 관찰하였다. 이상의 실험을 통해 얻은 결과는 다음과 같다. 1. 플라즈마 광과 LED 광원의 완속기시 중합방식은 각각의 기본 중합방식에 비해 중합 10분 후에 수축응력 감소를 보였다(P<0.05). 2. 완속기시 중합방식의 플라즈마 광이 가장 낮은 수축응력을 보였으나 미세경도 또한 가장 낮았다(P<0.05). 3. 완속기시 중합방식의 LED 광중합은 기존의 할로겐 광과 LED 광중합 방법에 비하여 낮은 수축응력을 보였다(P<0.05). 4. 완속기시 중합방식의 LED 광으로 조사한 시편의 미세경도는 단일광도로 조사한 할로겐 광과 LED 광중합과 비교하여 유의할만한 차이가 나타나지 않았다(P>0.05). 5. 기존의 할로겐 광과 완속기시 중합방식의 LED로 중합한 시편이 플라즈마 광과 단일강도의 LED로 조사한 군보다 더 나은 변연봉쇄를 보였다.

• 대한치과교정학회지
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• 제44권1호
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• pp.20-27
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• 2014

Objective: The aims of this study were to evaluate the relationship between the detachment force and bonding resin surface are and to determine the resin bonding surface area that would provide adequate bonding strength with minimum resin volume. Methods: One hundred and sixty human premolars were randomly divided into 4 groups of 40 teeth each. The diameter of the resin surface area in each group was as follows: group 1, 1.5 mm; group 2, 2.5 mm; group 3, 3.5 mm; and group 4, 4.5 mm. Respond Dead Soft straight (length 0.0175 inch) was used to fabricate the retainers, and $Transbond^{TM}$ XT was used to fix the retainers to the tooth surfaces. A pair of teeth was embedded in acrylic blocks for each specimen. Thus, each group comprised 20 samples. Fixed retainers were bonded to the teeth, and vertical force was applied at the middle of wire. The force was measured using a universal testing machine. Results: The mean value of detachment force was the highest for group 4 ($102.38{\pm}2.92N$), followed by group 3 ($63.54{\pm}2.21N$), group 2 ($51.95{\pm}1.61N$), and group 1 ($24.14{\pm}1.38N$). Conclusions: The detachment force of lingual fixed retainers was significantly affected as the area of the resin bonding surface increased. Considering the minimum bonding strength of brackets, a resin bonding surface area with a diameter of 3.5 mm would provide adequate bonding strength.

• The Journal of Advanced Prosthodontics
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• 제12권2호
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• pp.55-60
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• 2020

PURPOSE. The aim was to evaluate the effect of four acidic beverages on the roughness (Ra) and color change (ΔE_ab) of two brands of artificial teeth and a heat-polymerized acrylic resin (HPAR) for use in a prosthetic base. MATERIALS AND METHODS. All materials were divided into 5 groups, according to the used acidic beverage (artificial saliva - control, red wine, orange juice, coke-based, and lemon juice-based soft drink). The immersion process was divided into two stages: T1 - immersion in the acidic solutions for 10 minutes for 14 days; T2 - after T1, the samples were immersed in grape juice for 14 days. The Ra of the samples was evaluated in a rugosimeter and the ΔE_ab in a spectrophotometer, before and after the immersions. The analysis of variance of one (ΔE_ab) and two factors (Ra) and Tukey were performed (α=.05). RESULTS. There was a statistical difference for roughness after immersion (T1) for Trilux and Tritone teeth, regardless of the acid solution. For Trilux teeth, all acid solutions increased Ra (P<.05). For Tritone teeth, only the coke-based soft drink did not statistically change Ra. Grape juice (T2) altered Ra only of artificial teeth (P<.05). The color was changed for all materials, after T1 and T2. CONCLUSION. In general, the acidic solutions changed the Ra and ΔE_ab of HPAR and artificial teeth after T1. The grape juice altered the roughness only of the artificial teeth, promoting a clinically acceptable color change in the materials.

• The Journal of Advanced Prosthodontics
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• 제3권2호
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• pp.106-109
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• 2011

Oral cancer treatment involves the surgical removal of all or part of the maxilla, leaving the patient with a defect that compromises the integrity and function of the oral cavity. The postoperative restoration of esthetics, deglutition, and speech shortens recovery time in the hospital and expedites the patient's return to the community as a functioning member. The surgical obturator is the proven treatment option in such situations. This article describes a simple technique to fabricate a surgical obturator that restores patient's original dentition and facial and palatal tissue form. The obturator fabricated with this technique utilizes the vacuum formed index of patient's original tissue form and duplicated partly in heat and partly in auto polymerizing acrylic resin. Duplication of the original tissue form helps patient to minimize the immense physiological trauma immediately after the surgical resection. The obturator fabricated with this technique supports soft tissues after surgery and minimizes scar contracture and disfigurement, and thus may have a positive effect on the patients' psychology.

• The Journal of Advanced Prosthodontics
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• 제2권1호
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• pp.1-3
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• 2010

BACKGROUND. Even though excellent impression materials are now available for making accurate replication for hard and soft tissue, the numerous dentists have faced lots of obstacles in making simultaneous impressions of multiple abutments. CASE DESCRIPTION. This article describes a modified method of tray fabrication using auto-polymerizing acrylic resin and impression technique for multiple prepared teeth in cases with limitations and difficulties in taking dental impressions. CLINICAL IMPLICATION. This segmental tray technique has several advantages, including higher impression quality, fewer impressions, and being more comfortable for the patient and less stressful for the clinician.

• 구강회복응용과학지
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• 제39권4호
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• pp.222-228
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• 2023

교모는 치아 간의 접촉으로 인하여 치아 경조직이 소실되는 것으로, 심한 경우 상아질이 노출되어 선택적인 부식과 치아의 과도한 마모가 동반되는데, 이를 cupping이라고 부른다. 이러한 병소를 치료하지 않고 방치할 경우 병소의 크기가 점차 커지게 되어 지지되지 않는 법랑질이 파절되고, 결과적으로 심미성과 저작 기능이 저하된다. 본 증례보고에서는 심한 교모로 인해 cupping과 법랑질 파절이 동반된 환자에서 유기필러가 함유되어 부드러운 성질을 지닌 레진을 이용하여 직접수복을 실시하였다. 6년 후의 경과관찰에서 교합면의 충전은 대부분 탈락하였으나 협측의 충전은 비교적 온전하게 남아 있음을 관찰할 수 있었고, 이런 형태의 레진이 교합력이 크게 가해지는 부위보다는 교합력이 비교적 약하게 가해지는 부위에 적합한 재료임을 확인할 수 있었다.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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• pp.245-252
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• 2003

There have been many kinds of hair styling sprays with various setting effects. Consumers have used strong setting effect hair sprays to get a long lasting hold. In recent years, however, more and more consumers have come to prefer a "soft ＆ natural" touch feeling, keeping the same long lasting hold. Nonetheless, the existing approaches to this feature could not respond to the consumers′ needs, since products lose the hold strength if the soft feeling is pursued, and vice versa. We have researched and developed a new products to attain a compatible feature with both long lasting hold and natural feeling. Then, we have developed a new multifunctional hair styling material "Poly Amino Acid Derivative (PAAD)." We have focused on the PAAD′s feature that highly diffuses onto a hair and makes thin and even layer on a hair, and have made trials and errors to improve holding strength. "P AAD" excellently makes hair memorize its curl shape which is as the same effect as existing ordinary acrylic resin. Further more, it leaves a soft and natural touch feeling on the hair. We have accomplished a new Poly Amino Acid Derivative with ambivalent features, "soft ＆ natural finish" and "long lasting hold ", and now we report about it.

• 대한소아치과학회지
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• 제32권2호
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• pp.312-320
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• 2005

이 연구의 목적은 LED 광중합기(Elipar Freelight $2^{(R)}$, 3M-ESPE, USA)의 조사 mode에 따른 복합레진($Supreme^{(R)}$, Filtek $Flow^{(R)}$, 3M-ESPE, USA)의 수축응력과 미세경도를 평가하는 것이다. 수축응력을 측정하기 위해 스트레인 게이지가 사용되었다. 표본은 조사 mode와 충전방법에 따라 6개의 군으로 나누어졌다. A군 : Filtek $Flow^{(R)}$ 이장, $Supreme^{(R)}$ 충전, 10초 광중합, B군 : Filtek $Flow^{(R)}$ 이장 $Supreme^{(R)}$ 충전, 15초 광중합, C군 : Filtek $Flow^{(R)}$ 이장, $Supreme^{(R)}$ 충전, 15초 soft start 광중합, D군 : $Supreme^{(R)}$ 충전, 10초 광중합, E군 : $Supreme^{(R)}$ 충전, 15초 광중합, F군 : $Supreme^{(R)}$ 충전, 15초 soft start광중합. 스트레인 게이지를 아크릴릭 링에 부착하고 strainmeter에 연결한 후 광중합하고 10분 동안 1초 간격으로 측정하고 기록하였다. 24시간 후에 각각 표본의 미세경도를 측정하였다. 결과는 ANOVA와 Tukey test를 이용해 통계학적으로 분석하였다. 결과는 다음과 같았다. 1. Soft start curing 했을 때 수축응력이 낮았다(p<0.05). Flowable resin을 이장한 군에서는 효과가 없었다. 2. 10초간 조사한 군은 15초간 조사한 군에 비해 수축응력이 적었다(p<0.05). 3. 미세경도 측정결과 상면과 하면에서 각 군 간에 차이는 없었다(p>0.05). 하지만, 하면의 미세경도가 상면에 비해 80%에 이르지 못했다.