• The Journal of Advanced Prosthodontics
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• 제9권1호
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• pp.22-30
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• 2017

PURPOSE. The aim of this study was to investigate the effect of reinforcing materials on the fracture resistances of glass fiber mesh- and Cr-Co metal mesh-reinforced maxillary complete dentures under fatigue loading. MATERIALS AND METHODS. Glass fiber mesh- and Cr-Co mesh-reinforced maxillary complete dentures were fabricated using silicone molds and acrylic resin. A control group was prepared with no reinforcement (n = 15 per group). After fatigue loading was applied using a chewing simulator, fracture resistance was measured by a universal testing machine. The fracture patterns were analyzed and the fractured surfaces were observed by scanning electron microscopy. RESULTS. After cyclic loading, none of the dentures showed cracks or fractures. During fracture resistance testing, all unreinforced dentures experienced complete fracture. The mesh-reinforced dentures primarily showed posterior framework fracture. Deformation of the all-metal framework caused the metal mesh-reinforced denture to exhibit the highest fracture resistance, followed by the glass fiber mesh-reinforced denture (P<.05) and the control group (P<.05). The glass fiber mesh-reinforced denture primarily maintained its original shape with unbroken fibers. River line pattern of the control group, dimples and interdendritic fractures of the metal mesh group, and radial fracture lines of the glass fiber group were observed on the fractured surfaces. CONCLUSION. The glass fiber mesh-reinforced denture exhibits a fracture resistance higher than that of the unreinforced denture, but lower than that of the metal mesh-reinforced denture because of the deformation of the metal mesh. The glass fiber mesh-reinforced denture maintains its shape even after fracture, indicating the possibility of easier repair.

• 대한치과보철학회지
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• 제51권4호
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• pp.284-291
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• 2013

연구 목적: 상악 레진상 총의치의 정중 파절부에 금속선과 유리섬유 보강재를 사용하여 수리하였을 때 파절 강도 및 파절 양상을 비교해 보고자 하였다. 연구 재료 및 방법: 본 연구에서는 상악 의치의 정중부 파절을 재현한 뒤, 자가중합레진과 보강재를 사용하여 수리하였다. 보강재의 종류에 따라 3개의 군(대조군, 보강재 없음; W 군, 금속선; G 군, 섬유유리)으로 나누었으며, 각군당10개의 시편을 제작하였다. Instron test machine (Instron Co., Canton, MA, USA)으로 5.0 mm/min의 크로스헤드 속도를 부여하여 파절 강도를 구하였으며, 이때 하중은 20 mm의 지름을 가진 구형 하중체를 통해 의치 중심부에 전달되었다. 파절 강도 시험 후 나타난 의치의 파절 양상을 분석하였다. Kruskal-wallis test와 Mann-whitney U test를 이용하여 ${\alpha}=.05$ 수준에서 검정하였다. 결과: 파절 강도는W 군에서 가장 높은 값을 보였고, 대조군과 G 군 사이에서는 통계적으로 유의한 차이를 보이지 않았다(P>.05). 대조군과W군에서는 전후방파절 양상을 주로 보였고, G군에서는 보강재를 따라 파절되는 양상을 주로 보였다. 결론: 본 연구의 한계 내에서, 상악 총의치의 수리 시 유리섬유 보강재를 이용하는 경우 파절 강도가 향상되지 않았으며(P>.05), 유리섬유 보강재를 따라 접착 실패를 보이는 파절 양상이 나타났다.

• 대한치과보철학회지
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• 제43권1호
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• pp.52-60
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• 2005

Purpose. The intent of this study was to evaluate the effects of curing conditions on self-curing denture base resins to find out proper condition in self-curing resin polymerization. Materials and methods, In this study, 3 commercial self-curing denture base resins are used Vertex SC, Tokuso Rebase and Jet Denture Repair Acrylic. After mixing the self curing resin, it was placed in a stainless steel mold(3$\times$6$\times$60mm). The mold containing the resin was placed under the following conditions: in air at 23$^{\circ}C$; or in water at 23$^{\circ}C$; or in water at 23$^{\circ}C$ under pressure(20psi); or in water at 37$^{\circ}C$ under pressure(20psi) or in water at 50$^{\circ}C$ under pressure(20psi) , or in water at 65$^{\circ}C$ under pressure(20psi), respectively. Also heat-curing denture base resin is polymerized according to manufactures' instructions as control. Fracture toughness was measured by a single edge notched beam(SENB) method. Notch about 3mm deep was carved at the center of the long axis of the specimen using a dental diamond disk driven by a dental micro engine. The flexural test was carried out at a crosshead speed 0.5mm/min and fracture surface were observed under measuring microscope. Results and conclusion . The results obtained were summarized as follows : 1. The fracture toughness value of self-curing denture base resins were relatively lower than that of heat-curing denture base resin. 2. In Vertex SC and Jet Denture Repair Acrylic, higher fracture toughness value was observed in the curing environment with pressure but in Tokuso Rebase, low fracture toughness value was observed but there was no statistical difference. 3. Higher fracture toughness value was observed in the curing environment with water than air but there was no statistical difference. 4. Raising the temperature in water showed the increase of fracture toughness.

• 구강회복응용과학지
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• 제37권4호
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• pp.232-243
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• 2021

목적: 다양한 3D 프린팅 의치상 레진과 여러 가지 의치 첨상 재료 간의 전단결합강도를 평가하여 기존의 열중합 의치상 레진과의 전단결합강도를 비교 평가하고자 하였다. 연구 재료 및 방법: 열중합레진(Vertex RS)과 3D프린팅 의치상 레진 두종(DENTCA Denture base II, NextDent^TM Base)을 사용하였다. 의치 첨상 재료로는 성분이 다른 총 4종(Tokuyama Rebase II fast, Kooliner, Denture Liner, Denture Liner, Lang Jet Denture Repair Kit)을 사용하여 12개의 군으로 분류하였다. ISO/TS 11405규격에 따라 접착을 시행하였다. 전단결합강도를 측정하였고, 이후 입체현미경과 주사전자현미경을 이용하여 접착 계면을 관찰하고 파절편의 분석을 통하여 파절 양상을 조사하였다. 결과: 3D 프린팅 의치상 레진 군에서 의치 첨상 재료와의 전단결합강도가 열중합레진 군에 비해 유의하게 낮은 전단결합강도 결과를 나타내었다(P < 0.05). Polymethyl methacrylate계열의 첨상재료의 경우, 의치상종류와 관계없이 높은 전단결합강도를 보였다. 파절 양상은 대부분의 군에서 접착성 파절이 나타났고 일부 군에서 응집성 파절과 혼합성 파절 양상이 나타났다. 결론: Polymethyl methacrylate를 주성분으로 하는 의치 첨상 재료가 실험에 사용된 모든 의치상 레진에서 다른 의치 첨상 재료와 비교하여 높은 전단 결합강도 값을 나타내었지만, 직접법으로 의치 첨상을 시행할 경우 단량체로 Isobutyl methacrylate 성분의 의치 첨상재료를 사용하는 것이 전단결합강도면에서 유리할 것으로 사료된다.

• 대한치과보철학회지
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• 제50권4호
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• pp.279-284
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• 2012

연구 목적: 광중합형 레진에 미리 함침시킨 유리섬유를 이용하여 상악 레진상 총의치를 강화시킨 경우, 강화 부위의 위치가 파절 강도와 의치 파절 시 미치는 효과를 알아보기 위함이다. 연구 재료 및 방법: 본 연구에서는 0.45 mm의 두께를 가지고 광중합형 레진에 미리 함침시킨 유리섬유(SES MESH, INNO Dental Co., Yeoncheon-gun, Korea)를 이용하여 상악 총의치를 강화하였고, 강화재료의 위치 및 유무에 따라 5개의 군(대조군, 의치상을 섬유 망사로 강화하지 않음; A군, 순측 치조정 중앙부 강화; B군, 순측 치조정 하방의 구개 추벽부위 강화; C 군, 구개 중앙부위 강화; D 군, 의치상 전체 강화)으로 나누었으며, 군당6개의 시편을 제작하였다. 파절강도를 Instron test machine (Instron Co., Canton, MA, USA)을 이용해 5.0 mm/min의 크로스헤드 속도를 부여하여 구하였으며, 하중은 20 mm의 지름을 가진 구형 하중체를 통해 의치 중심부에 전달되었다. 파절 강도 시험 후 나타난 의치의 파절 양상을 분석하였다. 파절강도를 일원배치분산분석을 통해 검정하였다(${\alpha}$=.05). 결과: 파절강도에 있어 각 군간 통계적으로 유의한 차이를 보이지 않았다(P>.05). 의치의 파절 양상을 분석한 결과 A군에서는 전후방파절과 후방파절의 양상을 주로 보였고, B군, C군 그리고 대조군에서는 정중국소파절이 주로 관찰되었으며 D군에서는 대부분 후방파절을 보였다. 결론: 파절 강도를 측정하여 분석한 결과 유리 섬유에 의한 강화 유무와 위치에 따른 차이를 보이지 않았다. 의치의 파절 양상을 분석한 결과 유리 섬유에 의한 강화를 통해 균열을 억제하는데 효과를 보인다고 판단된다.

• 대한치과기공학회지
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• 제23권2호
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• pp.95-103
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• 2002

For this study, self curing resin and heat curing resin used for existing usual resin denture base in the denture industry were chosen by manufacturer. Curing tests for 30-minute, I-hour, 2-hour and 3-hour were conducted to know the strength of the resins and conduct analysis to get other necessary information. The results obtained are as follows: 1. Heat curing resins show a little differences among the manufacturers. However 30-minute curing resin shows great difference as shown in the fracture strength test. 2. The effect from the granularity of the resins on the fracture strength was found insignificant which means there is no difference between coherence and strength. 3. To summarize the results from each time level, the longer the time is, the more the minute cracks on the surface, which is the cause of reduced strength. From this test, it was identified that in making the denture base for patients in dental clinics, 30-minute curing is most efficient and effective in reducing discoloration and monomers, although long-time curing has been considered to be the principal.

• 대한치과보철학회지
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• 제34권2호
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• pp.363-372
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• 1996

A common site of fracture in maxillary complete denture is on the anteroposterior midline that coincides with the notch for relief of the labial frenum. Various approaches to reduce the incidence of this type of fracture have been suggested. The most widely used technique is the reinforcement of acrylic resin denture base with several solid metal forms. But few comparative studies on the efficacy of metal reinforcements have been reported. This study was conducted to compare reinforcing effects of commonly available metal reinforcements, which include wire, metal mesh embedded in the denture base and metal plate affixed to the impression surface of denture base by silicoating technique. This was load on the posterior. The strain gauges were oriented perpendicular to the anteroposterior midline of maxillary polished denture surface at one labial and the four palatal sites Non-renforced denture was used as control. The results were as follows : 1. In the non-reinforced denture group, only tensile strains on the palatal polished surface were observed. The tensile strains decreased in the order of incisive papilla, posterior denture border area, mid palatal area and rugae area. Compressive strain was observed on the labial polished surface. 2. As compared with the non-reinforced denture group, the metal plate or the metal mesh reinforced denture groups showed reduced palatal tensile strains,and the metal mesh reinforcement had a better reinforcing effect than the metal plate. But both reinforced denture groups showed no difference in the amount of compressive strain on the labial polished surface when compared to the non-reinforced denture group. 3. The metal wire positioned just above the labial notch decreased the compressive strain on the labial polished surface. But the presence of metal wires in the palatal polished surface caused increase in tensile strains in the area.

• 대한치과보철학회지
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• 제58권2호
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• pp.145-152
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• 2020

심미와 기능이 조화를 이루는 총의치 제작을 위해서는 상하악 관계를 정확히 기록하는 것이 필수적이다. 고딕아치 묘기법은 하악의 운동을 시각적으로 보여주며, 정확하고 반복재현성 있는 중심위를 확립하는데 유용하다. 또한, 고도의 치조제 흡수를 갖는 환자에서는 총의치의 적절한 유지 및 안정을 얻기가 어려운데, 이런 경우 환자의 생리적인 동작으로 변연을 형성하여 의치상연 주위가 가동점막으로 봉쇄되도록 하는 폐구 인상법이 유용할 수 있다. 본 증례에서는 우측 하악과두골절 병력과 고도의 하악 치조제 흡수를 보이는 환자에서 폐구인상법과 고딕아치 묘기법을 이용한 총의치로 수복하였고 만족할 만한 결과를 얻어 보고하는 바이다.

• 대한치과보철학회지
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• 제38권4호
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• pp.500-509
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• 2000

In general, the three major oral functions of edentulous patients-mastication, phonation, esthetics-can be rehabilitated by the complete dentures, and both the resin based complete denture and the metal based complete denture are commonly used by many clinicians today. For the sake of many advantages such as the excellent thermal conductivity, low volumetric change, high strength, low risk of fracture and the better patient's adaptation, the metal based complete dentures are indicated to the several cases. But, there are common failures of these type of dentures mainly by the fracture or the debonding between the resin structures and the metal frameworks which is caused by the discrepancies of the flexural strength and the coefficient of thermal expansion. This is aggravated by the water contamination of the interface when exposed to the oral environment and results in the failure of complete denture treatment. So, the purpose of this study is to compare the bond strength and the fracture patterns of the gold alloy based and the Co-Cr alloy based complete dentures using the PMMA resins and the 4-META adhesive resins. The results of this study were as follows. 1. Both to the PMMA resin and the 4-META resin, the flexural bond strength of gold alloy is lower than that of Co-Cr alloy(P<0.05) 2. To the Co-Cr alloy, the bond strength of the 4-META resin is significantly higher than that of PMMA resin(P<0.05). 3. The flexural strength of the group with the mechanical retention form is significantly higher than that of the group without retention form(P<0.05). 4. Comparing with the other groups, the fracture patterns of the group 3 are quite different from the group 1,2,5.

• The Journal of Advanced Prosthodontics
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• 제6권5호
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• pp.325-332
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• 2014

PURPOSE. The aim of this review was to analyze the evaluation criteria on mandibular implant overdentures through a systematic review and suggest standardized evaluation criteria. MATERIALS AND METHODS. A systematic literature search was conducted by PubMed search strategy and hand-searching of relevant journals from included studies considering inclusion and exclusion criteria. Randomized clinical trials (RCT) and clinical trial studies comparing attachment systems on mandibular implant overdentures until December, 2011 were selected. Twenty nine studies were finally selected and the data about evaluation methods were collected. RESULTS. Evaluation criteria could be classified into 4 groups (implant survival, peri-implant tissue evaluation, prosthetic evaluation, and patient satisfaction). Among 29 studies, 21 studies presented implant survival rate, while any studies reporting implant failure did not present cumulative implant survival rate. Seventeen studies evaluating peri-implant tissue status presented following items as evaluation criteria; marginal bone level (14), plaque Index (13), probing depth (8), bleeding index (8), attachment gingiva level (8), gingival index (6), amount of keratinized gingiva (1). Eighteen studies evaluating prosthetic maintenance and complication also presented following items as evaluation criteria; loose matrix (17), female detachment (15), denture fracture (15), denture relining (14), abutment fracture (14), abutment screw loosening (11), and occlusal adjustment (9). Atypical questionnaire (9), Visual analog scales (VAS) (4), and Oral Health Impact Profile (OHIP) (1) were used as the format of criteria to evaluate patients satisfaction in 14 studies. CONCLUSION. For evaluation of implant overdenture, it is necessary to include cumulative survival rate for implant evaluation. It is suggested that peri-implant tissue evaluation criteria include marginal bone level, plaque index, bleeding index, probing depth, and attached gingiva level. It is also suggested that prosthetic evaluation criteria include loose matrix, female detachment, denture fracture, denture relining, abutment fracture, abutment screw loosening, and occlusal adjustment. Finally standardized criteria like OHIP-EDENT or VAS are required for patient satisfaction.