• Restorative Dentistry and Endodontics
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• 제12권1호
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• pp.85-93
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• 1986

The purpose of this study was to investigate the curing effect of visible light through tooth substance, 0.5mm, 1.0mm thickness of enamel and dentin were prepared. Experimental specimen were made by Bisfil M & Silux packing into cylindrical brass mold 6.0mm in diameter, 2.0mm and 3.0mm, in height. All specimen were irradiated by visible light (Grip type) model No. SDL-50 Shofu Co.) for 30 seconds through tooth substance. Experimental groups were classified into enamel group (group 1) and dentin group (group 2) according to the thickness of tooth materials and then were divided into 2 subgroups (0.5mm group and 1.0mm group). In experimental groups, visible light irradiated to the specimen through either 0.5mm in thick or 1.0mm in think of tooth material. In Control group specimen were prepared by direct irradiation on the specimen surface of visible light without through tooth substance. The hardness was measured with a Barcol hardness tester (Barber-Colman Co. U.S.A.) for each prepared specimen. The results were as follows: 1. In control group, there were higher hardness values than those of in experimental group. 2. In experimental groups, 0.5mm groups had higher hardness values than 1.0mm groups did. 3. The hardness value at top surface of the specimen were higher than the hardness of bottom surface in each group. 4. Bisfil M had higher hardness values than Silux. 5. In all specimen of 3.0mm height polymerization effect was not occurred at bottom surface except Bisfil M in control group.

• Journal of Oral Medicine and Pain
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• 제30권2호
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• pp.269-276
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• 2005

재래의 고속핸드피스 bur를 이용한 와동 형성시 레진 접착력과 레이저를 사용한 와동형성시 접착력을 비교하여 레이저의 임상적용 여부를 평가하는 것이 본 연구의 목적이다. 총 96개 치아 표본의 법랑질 협면과 상아질 mid-coronal 부에 Er:YAG laser를 사용하여 조사하였다. 사전에 산부식을 시킨 군(48개)과 부식시키지 않은 군(48개)으로 구별하고 각각 flowable 접착시스템(Metafil Flo)과 자가중합 시스템(Clearfil FII New Bond)를 레진에 접착시켰다. 37$^{\circ}C$ 증류수에서 24시간동안 보관한 후 미세 결합강도(micro-tensile shear strength)를 만능시험기(universal testing machine)로 측정하여 다음과 같은 결과를 얻었다. 1. 법랑질과 상아질 모두 산부식 전처리를 한 경우에 산처리를 하지 않은 경우보다 결합강도가 높았고, 레이저 처리 표본에서도 마찬가지여서 레이저만으로 처리하는 것보다는 산부식 처리를 하는 것이 강도면에서 유리한 것으로 나타났다. 2. 법랑질의 경우 레이저 처치한 경우가 bur로 삭제한 경우보다 두 레진군 모두에서 결합강도가 낮았으나(P<0.05), 상아질의 경우에는 flowable 레진군에서는 두 군 간의 차이가 없었다. 3. 레이저 처치군내에서 상아질의 경우, 광중합 flowable 레진의 결합강도가 자가중합형 레진의 강도보다 높았으나, 법랑질에서는 차이가 없었다. 따라서 레이저를 활용하여 와동을 형성하는 것은 상아질까지 확대된 와동의 경우에 법랑질에 국한된 경우보다 결합강도면에서 유리하며, flowable레진을 사용하는 것이 자가중합형 레진보다 유리한 것으로 판단되었다.

• 대한소아치과학회지
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• 제25권1호
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• pp.62-75
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• 1998

The main purpose of this study was to compare the anticariogenecity of glass ionomer restorative material polymerized by argon laser versus visible light, The results from the present study can be summarized as follows; 1. Under the polarized light microscope, the specimens of laser-cured group showed the shallower lesion body than that of visible-light cured group, both in the stage of lesion initiation and progression. 2. Glass ionomer material cured by visible light showed shallower body of lesion than that of composite resin cured by argon laser at the stage of lesion progression(p<0.05). It was suggested fluoride released from the glass ionomer might have the additive anticariogenic effect. 3. Statistical difference between groups on depth of lesion body was evident after lesion progression (p<0.05). It was suggested that anticariogenic effect by argon laser was more effective at the stage of lesion progression than the lesion initiation. 4. The increment of lesion body during progression was highest in group IV (p<0.05). 5. Based upon the above-mentioned results of this study, it can be concluded that the advantage of anticariogenic effect and short curing time of argon laser in glass ionomer polymerization should be considered in children and adolescents whose caries activity is relatively higher.

• Restorative Dentistry and Endodontics
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• 제22권1호
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• pp.61-75
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• 1997

The bond strengths of composite resin to tooth dentin vary with the methods of cavity preparation and surface treatment. Recent developments in techniques of dentinal surface treatment have renewed interest in microabrasive as a means of tooth preparation, The purpose of this study was to determine the effects of a new method of cavity preparation on the bond of composite resin to dentin. Freshly extracted 144 healthy human third molars were used in this study. The dentin surfaces prepared with #600 SiC abrasive paper were divided into control and air abrasion groups according to the method of dentin surface preparation using different combinations of delivery pressure, time, and acid etching. The shear bond strengths were measured after the composite resin (Clearfil Photo Bright) was bonded to prepared dentin surfaces by light-curing using a dentin bonding system (All-bond 2), In addition, the average surface roughness was measured to investigate the effect of differently prepared dentin surfaces on the shear bond strengths. The surface changes of prepared dentin and the debonded dentin surfaces were observed with SEM (S-2300, Hitachi Co., Japan). The following results from this-study were obtained ; 1. There was no significant difference of shear bond strengths according to the changes of delivery pressure and time. 2. The shear bond strengths were lower than the control in the air abraded-only groups, but those of the additional acid-etched groups were higher than the control. 3. The shear bond strengths to all air-abraded surfaces were increased by acid etching. 4. The correlation between shear bond strengths and surface roughness was not certain, although the mean surface roughness of all air-abraded surfaces has increased evidently while it has slightly decreased for additional acid etching. 5. On SEM examination, the dentinal tubules were almost occluded in the air abraded-only groups, but those were opened in the additional acid-etched groups. 6. The debonded surfaces were showed adhesive failure mode in the air abraded- only groups, while those were showed mainly the mixed and cohesive failure mode in the additional acid-etched groups. These results suggest that the layer produced during cavity preparation or surface treatment with air abrasion must be removed for maximum bond strength of composite resin to dentin.

• Restorative Dentistry and Endodontics
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• 제36권6호
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• pp.490-497
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• 2011

연구목적: 본 연구는 간접 레진수복시 상아질 접착제의 중합 여부가 레진인레이와 상아질간의 미세인장결합강도와 결합계면의 형태에 미치는 영향을 공초점 현미경 관찰을 통하여 평가하고자 하였다. 연구 재료 및 방법: 24개의 발거된 대구치를 절단하여 교합면 상아질을 노출시켰다. 수복 방법에 따라 크게 간접 레진수복과 직접 레진수복의 두 군으로 나누었다. 간접 레진수복군은 임시 수복하여 1주일 후, 상아질 접착 과정에 따라 4군(OB-C와 OB-NC군, OS-C와 OS-NC군)으로 나누었다. 간접 레진수복군은 산부식 처리된 상아질면에 OptiBond FL (Kerr) 또는 One-Step (Bisco) 상아질 접착제를 중합 여부에 따라 나누어 적용하였다. 처리된 상아질면에 제작된 3 mm 높이의 레진 인레이(Tescera, Bisco)를 Variolink II (Ivoclar Vivadent)를 사용하여 제조사의 지시에 따라 합착하였다. 직접 레진수복군은 산부식 처리된 상아질면에 상아질 접착 후, 복합레진 (Estelite${\Sigma}$, Tokuyama)으로 즉시 수복하였다(OB-D군, OS-D군). 수복을 마친 모든 치아는 24시간 후, 미세인장 결합 강도 평가와 공초점 레이저 주사 현미경 관찰(CLSM)을 시행하였다. 결과: 간접 레진수복군은 직접 레진수복군에 비하여 낮은 미세인장결합강도를 나타내었으며, 상아질 접착제를 광중합한 군(OB-C군, OS-C군)이 광중합을 시행하지 않은 군(OB-NC군, OS-NC군)에 비하여 높은 미세인장결합강도를 나타내었다. 접착 계면에 대한 CLSM 관찰에서 상아질 접착제를 광중합한 군에서 더 분명하고 균일한 혼성층이 관찰되었다. 상아질 접착제를 광중합하지 않은 군에서는 혼성층이 불분명하거나 거의 관찰되지 않았다. 결론: 간접 레진수복물의 합착시 레진시멘트의 적용 전에 상아질 접착제의 광중합은 분명하고 균일한 혼성층의 형성하며, 이는 결합강도의 향상에 기여한다.

• The Journal of Advanced Prosthodontics
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• 제5권2호
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• pp.98-103
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• 2013

PURPOSE. To evaluate the effects of hydrofluoric acid etching and Er,Cr:YSGG laser irradiation on the shear bond strength of resin cement to lithium disilicate ceramic. MATERIALS AND METHODS. Fifty-five ceramic blocks ($5mm{\times}5mm{\times}2mm$) were fabricated and embedded in acrylic resin. Their surfaces were finished with 1000-grit silicon carbide paper. The blocks were assigned to five groups: 1) 9.5% hydrofluoric-acid etching for 60 s; 2-4), 1.5-, 2.5-, and 6-W Er,Cr:YSGG laser applications for 60 seconds, respectively; and 5) no treatment (control). One specimen from each group was examined using scanning electron microscopy. Ceramic primer (Rely X ceramic primer) and adhesive (Adper Single Bond) were applied to the ceramic surfaces, followed by resin cement to bond the composite cylinders, and light curing. Bonded specimens were stored in distilled water at $37^{\circ}C$ for 24 hours. Shear bond strengths were determined by a universal testing machine at 1 mm/min crosshead speed. Data were analyzed using Kruskal-Wallis and Mann-Whitney U-tests (${\alpha}$=0.05). RESULTS. Adhesion was significantly stronger in Group 2 ($3.88{\pm}1.94$ MPa) and Group 3 ($3.65{\pm}1.87$ MPa) than in Control group ($1.95{\pm}1.06$ MPa), in which bonding values were lowest (P<.01). No significant difference was observed between Group 4 ($3.59{\pm}1.19$ MPa) and Control group. Shear bond strength was highest in Group 1 ($8.42{\pm}1.86$ MPa; P<.01). CONCLUSION. Er,Cr:YSGG laser irradiation at 1.5 and 2.5 W increased shear bond strengths between ceramic and resin cement compared with untreated ceramic surfaces. Irradiation at 6 W may not be an efficient ceramic surface treatment technique.

• Restorative Dentistry and Endodontics
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• 제16권1호
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• pp.200-208
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• 1991

The purpose of this study was to observe shear bond strength of composite resin to dentin following surface treatment. Freshly extracted forty-eight sound human molars were used in this study. They were stored at $4^{\circ}C$ physiologic saline solution before experiment. The teeth was then mounted with self curing acrylic resin in brass mold. The buccal surfaces of the teeth were grinding approximately 1.5mm by means of water-irrigated grinding wheel to expose the flattened fresh dentin surfaces. The specimens were divided into 6 groups according to preparation and treatment procedures on dentin surfaces; Group 1: Untreated after preparation with No.301 diamond point Group 2: Treated with primer for 60 seconds after preparation with No.301 diamond point Group 3: Untreated after preparation with No.700 fissure carbide bur Group 4: Treated with primer for 60 seconds after preparation with No.700 fissure carbide bur Group 5: Untreated after grinding with 600 grit silicon carbide paper Group 6: Treated with primer for 60 seconds after grinding with 600 grit silicon carbide paper Light cure dental adhesive was applicated to each specimen. Silux plus(3M) was inserted then into polyethylene tube of 3mm diameter and 3mm height, and polymerized to dentin surface. All of the specimens were stored in distilled water at $35.6^{\circ}C$ for 24 hours prior to testing. The shear bond strength was measured using an Instron Universal Testing Machine. The results obtained from this study were as follows: 1. The shear bond strength to dentin was the highest in group II. 2. The shear bond strength to dentin was the lowest in group III. 3. There was no significant difference in shear bond strength to dentin according to preparation instrument. 4. The primer treatment group showed significantly greater shear bond strength than untreated group.

• 대한치과보철학회지
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• 제38권3호
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• pp.366-374
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• 2000

FRC/ceromer system provides the clinician with a durable, flexible, and esthetic alternative to conventional porcelain fused to metal crowns. FRC is the matrix which is silica-coated and embedded in a resin matrix. The ceromer material which is a second generation indirect composite resin contains silanized, microhybrid inorganic fillers embedded in a light-curing organic matrix. FRC/ceromer restoration has a several advantages: better shock absorption, less wear of occluding teeth, translucency, color stability, bonding ability to dental hard tissues, and resiliency. It has versatility of use including inlay, onlay, single crown, and esthetic veneers. With adhesive technique, it can be used for single tooth replacement in forms of inlay adhesion bridge. In single tooth missing case, conventional PFM bridge has been used for esthetic restoration. However, this restoration has several disadvantages such as high cost, potential framework distortion during fabrication, and difficulty in repairing fractures. Inlay adhesion bridge with FRC/ceromer would be a good alternative treatment plan. This article describes a cases restored with Targis/Vectris inlay adhesion bridge. Tooth preparation guide, fabrication procedure, and cementation procedure of this system will be dealt. The strength/weakness of this restoration will be mentioned, also. If it has been used appropriately in carefully selected case, it can satisfy not only dentist's demand of sparing dental hard tissue but also patient's desire of seeking a esthetic restorations with a natural appearance.

• Restorative Dentistry and Endodontics
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• 제34권6호
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• pp.467-476
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• 2009

본 연구의 목적은 아말감과 복합레진의 수복 과정과 수복 후 상아세관액의 흐름(dentinal fluid flow, DFF)을 측정하기 위함이다. 치근을 절제한 제 3 대구치를 자체 제작한 미세 유체 흐름 측정장치에 연결한 후 1급 와동을 형성하여 아말감과 복합레진 수복을 시행하였다. DFF의 측정은 와동 형성부터 수복 후 30분까지 연속적으로 이루어졌고, 수복 후 3, 7일에 재 측정하였다. 주수 하에 와동 형성 시 DFF는 inward로, 끝난 후에는 outward로 바뀌었다. 아말감 충전 시 DFF는 inward로 바뀌었고 충전 완료 후 미약한 outward DFF를 보였다. 복합레진 수복의 경우, 산 처리 후 수세와 건조 시 각각 inward와 outward DFF를 보였고 primer도포 후 공기 분사는 급격한 outward, 소수성 본딩제를 적용하는 단계에서는 outward 였던 DFF가 감소하여 0에 가까워지거나 약간 inward 흐름을 보였다. 접착제와 복합레진의 광중합은 급격한 inward의 DFF를 일으켰다. 수복 후 30분, 3일, 7일째 수복 재료에 따른 DFF의 감소에 통계적으로 유의한 차이는 없었다 (p>0.05).

• 대한소아치과학회지
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• 제26권3호
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• pp.520-527
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• 1999

본 연구는 현재 널리 쓰이고 있는 sandwich technique을 임상에 적용함에 있어서, GIC 이장재에 대한 이중중합형 레진과 비교적 근래에 소개된 compomer의 결합력을 측정하여 기존의 광중합형, 화학중합형 복합레진과 비교하고, 가장 우수한 결합력을 보이는 glass ionomer-composite resin의 조합을 밝혀내고자 시도되었다. 이장용 재료로는, 광중합형 GIC인 Vitrebond와 화학중합형 GIC인 Ketac-fil을 사용하였으며, 이 두 가지의 이장재에 대해, 광중합형 복합 레진인 Z-100, 화학중합형 복합 레진인 Clearfil, compomer인 Dyract, 그리고 이중중합형 복합 레진인 Bis-core를 축조하여 각 군당 10개씩, 총 80개의 시편을 제작하였다. 제작된 시편은 $37^{\circ}C$의 증류수에 24시간동안 보관한 후, full load scale 50kg, cross-head speed 1mm/min 조건의 만능 시험기에서 그 전단결합강도를 측정하였으며 실험결과는 student t-test로 검정하였다. 본 연구의 결과는 다음과 같다. 1. Vitrebond를 이장재로 사용한 경우, Z-100이 가장 낮은 결합강도를 보였으며, 나머지 세 재료는 결합력의 차이를 보이지 않았다(P>0.05). 2. Ketac-fil을 이장재로 사용한 경우, Clearfil이 가장 높은 결합강도를 보였고, Dyract, Bis-core가 중등도의 결합강도를, Z-100이 가장 낮은 결합강도를 보였다(P<0.05). 3. Clearfil은 Vitrebond 상방에서는 타 재료들과 비슷한 결합강도를 보였으나, Ketac-fil 상방에서는 가장 강한 결합강도를 보임으로써, GIC 이장재의 종류에 따른 결합력의 차이를 보였으나 (P<0.05), 나머지 세 재료의 경우에는 차이를 보이지 않았다(P>0.05). 4. Vitrebond를 사용할 때보다 Ketac-fil을 이장재로 사용할 때, 상부에 축조되는 복합레진의 종류에 따른 결합력의 차이가 더 크게 나타났다(P<0.05).