• 대한치과보철학회지
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• 제44권1호
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• pp.1-9
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• 2006

Purpose: The purpose of this study was to evaluate the efficacy and substitute possibility of a newly developed flowable composite resins as a luting cement for translucent fiber post. Material & Method: Two kinds of 12 mm translucent fiber Post (D.T. Light-Post (Bisco, USA) and FRC Postec (Ivoclar vivadent, Liechtenstein) was inserted into the teflon mold (7 mm diameter, 9 mm long) and Filtek-Flow (3M ESPE. USA), a light activated flowable composite resin, was polymerized for 60 seconds through the post. Also, the post was cut from the tip to 9 mm, 6 mm, 3 mm, and Filtek-Flow was light cured according to each length. For comparison, 60 seconds light-cured and 24 hours self-cured two dual cured resin cement (Duo-cement (Bisco, USA) and 2 Panavia-F (Kuraray, Japan)) samples were prepared as control group. Also cavities (1 mm in width, 1 mm in depth and 12 mm in length) were prepared using acrylic plate and aluminum bar, and flowable composite resin was flied and light cured by the diffused light from the fiber post's side wall. The degree of polymerization was measured according to the distance from curing light using Vickers' hardness test. Result: Within the limitation of this study, the following conclusions were drawn: 1. Vickers' hardness of light cured dual cured resin cement and flowable composite resin decreased from Panavia-F, Filtek-Flow and Duo-cement accordingly (p<0.05). In the dual curing resin cement, light curing performed group showed higher surface hardness value than self cured only group (p<0.05). 2. Surface hardness ratio (light cured through fiber post /directly light cured) of D.T. Light-Post using Filtek-Flow showed about 70% in the 6 mm deep and about 50% in the 12 mm deep FRC Postec showed only 40% of surface hardness ratio. 3. Surface hardness ratio by diffused light from the post's side wall showed about 50% at 6 mm and 9 mm deep, and about 40% at 12 mm deep in D.T. Light-Post. However, FRC Postec showed about 40% at 6 mm deep, and almost no polymerization in 9 mm and 12 mm deep.

• Restorative Dentistry and Endodontics
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• 제26권4호
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• pp.332-340
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• 2001

Flowable composite resin has lower filler content, increased flow, and lower modules of elasticity. It is suggested that flowable composite resin can be bonded to the tooth structure intimately and absorb or dissipate the stress. Therefore, it may be advantageous to use flowable composite resin for the base material of class II restoration and for the class V restoraton. The purpose of this study was to evaluate the microleakage and shear bond strength of four flowable composite resins (Aeliteflo, Flow-It, Revolution, Ultraseal XT Plus) compared to Z100 using Scotchbond Multi Purpose dentin bonding system. To evaluate the microleakage, notch-shaped class V cavities were prepared on buccal and lingual surfaces of 80 extracted human premolars and molars on cementum margin. The teeth were randomly divided into non-thermocycling group (group 1) and thermocycling group (group 2) of 40 teeth each. The experimental teeth of each group were randomly divided onto five subgroups of eight samples (sixteen surfaces). The Scotchbond Multi-Purpose and composite resin were applied for each group following the manufacturer's instructions. the teeth of group 2 were thermocycled five hundred times between 5$^{\circ}C$ and 55$^{\circ}C$. The teeth of group 2 were placed in 2% methylene blue dye for 24 hours, then rinsed with tab water. The specimens were embedded in clear resin, and sectioned longitudinally with a diamond saw. The dye penetration on each of the specimen were observed with a stereomicioscope at $\times$20 magnification. To evaluate the shear bond strength, 60 teeth were divided into five groups of twelve teeth each. The experimental teeth were ground horizontally below the dentinoenamel junction, so that no enamel remained. After applying Scotchbond Multi-Purpose on the dentin surface, composite resin was applied in the shape of cylinder. The cylinder was 4mm in diameter and 2mm in thickness. Shear bond strength was measured using Instron with a cross-head speed of 0.5mm/min. After shear bond strength measurement, mode of failure was evaluated with a stereomicroscope at $\times$30 magnification. All data were statistically analyzed by One Way ANOVA and Student-Newman-Keuls method. The correlation between microleakage and shear bond strength was analyzed by linear regression. The results of this study were as follows ; 1. In non-thermocycling group, the leakage value of Z100 was significantly lower than those of flowable composite resins at the enamel and dentin margin, margin, except that Revolution showed the lower leakage value than that of Z100 at the dentin margin (p<0.05). 2. In thermocycling group, the leakage values of Z100 and Ultraseal XT Plus were lower than those of other subgroup at the enamel and dentin margin, except that Flow-It showed the lower leakage value than that of Ultraseal XT Plus at the dentin margin (p<0.05). 3. The leakage value of Z100 and Ultraseal XT Plus in thermocycling group were not higher than that in non-thermocycling group at the enamel margin. The leakage value of Z100 in thermocycling group was not higher than that in non-thermocycling group at the dentin margin (p<0.05). 4. As for the shear bond strength measurement, there were no statistically significant differences among groups (p<0.05). The shear bond strengths given in descending order were as follows: Z100(16.81$\pm$2.98 MPa), Flow-It(14.8$\pm$4.43 MPa), Aeliteflo(14.34$\pm$3.69 MPa), Revolution(13.46$\pm$4.23 MPa), Ultraseal XT Plus(12.83$\pm$3.16 MPa). 5. Failure modes of all specimens were adhesive failures. 6. There was no correlation between microleakage and shear bond strength.

• The Journal of Advanced Prosthodontics
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• 제9권4호
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• pp.257-264
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• 2017

PURPOSE. To evaluate the adhesion to CAD/CAM feldspathic blocks by failure analysis and shear bond strength test (SBSt) of different restorative systems and different surface treatments, for purpose of moderate chipping repair. MATERIALS AND METHODS. A self-adhering flowable composite (Vertise Flow, Kerr) containing bi-functional phosphate monomers and a conventional flowable resin composite (Premise Flow, Kerr) applied with and without adhesive system (Optibond Solo Plus, Kerr) were combined with three different surface treatments (Hydrofluoric Acid Etching, Sandblasting, combination of both) for repairing feldspathic ceramics. Two commercial systems for ceramic repairing were tested as controls (Porcelain Repair Kit, Ultradent, and CoJet System, 3M). SBSt was performed and failure mode was evaluated using a digital microscope. A One-Way ANOVA (Tukey test for post hoc) was applied to the SBSt data and the Fisher's Exact Test was applied to the failure analysis data. RESULTS. The use of resin systems containing bi-functional phosphate monomers combined with hydrofluoric acid etching of the ceramic surface gave the highest values in terms of bond strength and of more favorable failure modalities. CONCLUSION. The simplified repairing method based on self-adhering flowable resin combined with the use of hydrofluoric acid etching showed high bond strength values and a favorable failure mode. Repairing of ceramic chipping with a self-adhering flowable resin associated with hydrofluoric acid etching showed high bond strength with a less time consuming and technique-sensitive procedure compared to standard procedure.

• 대한소아치과학회지
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• 제50권4호
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• pp.434-442
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• 2023

This study was aimed to evaluate the bonding performance of a self-adhesive giomer and compare it to a conventional flowable composite resin with regard to shear bond strength and microleakage in enamel and dentin. Healthy human premolars extracted for orthodontic treatments were used in the study. For shear bond strength tests, enamel and dentin specimens were prepared for the study group with self-adhesive giomer and for the control group with conventional flowable composite resin with a 5th-generation adhesive system. A universal testing machine was used to measure the shear bond strength. For the microleakage tests, specimens were immersed in a 2% methylene blue solution for 24 hours, cut into sections, and evaluated with a stereomicroscope for the extent of dye penetration. The results of the study showed no statistically significant difference in shear bond strength between the self-adhesive giomer and the conventional flowable composite resin in enamel (p = 0.091). On the contrary, in dentin, the self-adhesive giomer showed significantly lower shear bond strength (p < 0.0001). The microleakage of the self-adhesive giomer was significantly higher than that of the conventional flowable composite resin (p = 0.002). Self-adhesive giomer is considered useful for restoring small cavities at the enamel level of pediatric patients by reducing chair time with the advantage of a simple bonding process. However, as the study was conducted in a laboratory setting, further research in a clinical environment is deemed necessary.

• 대한소아치과학회지
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• 제29권2호
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• pp.255-261
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• 2002

유동성 복합레진은 치면 열구 전색이나 작은 교합면 우식의 예방적 레진 수복 및 깊은 와동의 이장재로 사용할 수 있으나 이에 대한 임상적 연구는 부족한 실정이다. 본 연구는 유동성 복합레진이 치면 열구 전색, 예방적 레진 수복, 깊은 와동의 이장의 세 가지 임상적 용도로 적용될 경우, 기존의 재료와 비교한 대체가능성과 타당성을 검토할 목적으로, 각 용도에서의 양재료들이 나타내는 미세누출 양상을 비교분석하였다. 교합면이 건전한 120개의 발거된 대구치를 6개의 군으로 나누어 각 군당 20개색 시편을 구성하였다. 제 1군과 2군에는 각각 Concise와 Tetric flow로 치면 열구 전색을, 제 3군에는 Z-100과 Concise, 제 4군에는 Tetric flow로 예방적 레진 수복을 시행하였으며, 제 5군에는 Vitrebond, 제 6군에는 Tetric flow를 이장재로 이용하여 sandwich technique 수복을 시행하였다. 100회의 열 순환 및 색소 침투후 색소 침투 정도를 관찰하고 미세누출 정도를 판단하여 비교, 분석한 결과 다음과 같은 결론을 얻었다. 1. 열구 전색재인 Concise와 유동성 복합레진인 Tetric flow로 각각 치면 열구 전색을 시행한 경우 미세누출의 차이가 나타나지 않았다(p>0.05). 2. 복합레진인 Z-100과 열구전색재인 Concise로 예방적 레진 수복을 시행한 군과 유동성 복합레진인 Tetric flow 단일 재료로 수복한 군 간에도 미세누출의 차이는 없었다(p>0.05). 3. 이장재로 Resin-modified glass ionomer cement 인 Vitrebond와 유동성 복합레진인 Tetric flow를 사용하여 sandwich technique으로 복합레진 수복을 시행한 경우에도 양 군간에 미세누출의 차이는 나타나지 않았다(p>0.05).

• 대한소아치과학회지
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• 제33권2호
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• pp.233-243
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• 2006

와동 형성시 C-factor와 충전방법이 복합레진 수복물에서의 수축 응력에 미치는 영향을 평가하고자 발거된 소구치를 대상으로 C-factor가 3.6과 1.0인 와동을 각각 형성한 후 hybrid형 복합레진인 $Z-250^{TM}$(3M ESPE U.S.A.)과 flowable형 복합레진인 $Filtek\;flow^{TM}$(3M ESPE U.S.A.)를 사용하여 layering을 시행하고 광중합하면서 strain gauge법을 이용하여 치질에서의 수축 응력을 측정하였다. 시편을 절단하여 레진과 상아질 사이 계면의 접착상태를 주사전자현미경으로 관찰한 결과 다음과 같은 결과를 얻었다. 1. C-factor에 따른 수축 응력을 측정한 결과 C-factor가 3.7인 제 1군과 제 2군 그리고 제 5군이 900초 후 각각 0.11, 0.07, 0.07 MPa로 C-factor가 1.0인 제 3군과 제 4군의 0.05와 0.04 MPa에 비해 크게 나타났다(P<0.05). 1,800초 후에는 제 1군, 제 5군, 제 2군, 제 3군, 제 4순으로 크게 나타났으나 제 2군과 제 3군 그리고 제 3군과 제 4군 사이에는 유의성이 없었다. 2. 재료에 따른 수축 응력의 차이는 C-factor가 3.7인 와동의 경우 hybrid형 레진인 Filtek $Z-250^{TM}$이 flowable 레진인 $Filtek\;flow^{TM}$에 비해 수축 응력이 크게 나타났으나(P<0.05), C-factor가 1.0인 와동의 경우 재료의 차이에 따른 수축응력의 유의한 차이가 없었다. 3. Layering에 따른 수축 응력은 Filtek $Z-250^{TM}$을 layering 없이 bulk 충전한 제 1군에 비해 flowable 레진을 layering한 제 5군이 전 측정 시간대에 걸쳐 수축 응력이 유의하게 낮게 나타났다(P<0.05). 4. C-factor가 3.7인 제 1군과 제 2군 제 5군은 900초까지 수축 응력이 증가하다 이후 점차 감소하는 경향을 보였다. 5. C-factor가 1.0인 와동의 경우 충전용 레진 종류에 관계없이 레진과 와동벽 사이에 긴밀한 접착 상태를 보였으나 C-factor가 3.7인 와동의 경우 부분적으로 틈이 관찰되었다. 전반적으로 와동저에 비해 와동벽에서 틈이 더 많이 관찰되었다. 이상의 결과를 종합하여 보면 복합레진 수복시 수축응력에 따른 합병증을 예방하기 위해 C-factor를 크지 않게 와동을 설계, 형성하여야 하며 C-factor가 클 경우 flowable 레진을 이장하는 등 재료적인 면에서의 선택과 적용법이 중요할 것으로 사료된다.

• 대한치과보철학회지
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• 제46권2호
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• pp.105-115
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• 2008

전치부 영역에서의 복합 레진을 이용한 수복물의 표면은 착색과 치태 침착이 적어야 하며 치은 조직에 좋은 내성을 갖도록 평활해야 한다. 레진 수복 후 여러 마무리 방법중 blade를 이용한 방법은 치은과 접해있는 변연 부위의 불필요한 레진을 제거하고 마무리하는데 있어 치은 손상을 최소화하면서 간편하게 이용할 수 있는 방법이다. 본 연구의 목적은 현재 많이 사용되고 있는 nano-hybrid composite resin과 ormocer-based compostie resin 간의 여러 가지 마무리 방법에 있어 blade를 이용한 방법과 polishing을 시행한 경우의 표면 거칠기 및 nano계열과 ormocer 계열 복합 레진의 표면 특징을 비교하는 것으로 실험을 위해 가로 6mm, 세로 3mm, 높이 2mm의 금속 주형을 이용하여 레진 블록을 형성하고 대조군은 상면에 mylar strip을 위치시켜 광중합 하였으며, Ormocer - based composite resin ($Admira^{(R)}$)과 nanohybrid composite resin ($Grandio^{(R)}$)에서는 blade를 이용한 경우와 rubber polishing을 이용한 경우를 실험군으로 하였고, ormocer-based flowable composite resin ($Admira^{(R)}$ Flow)과 nanohybrid flowable composite resin ($Grandio^{(R)}$ Flow)에서는 blade를 이용한 경우, rubber polishing을 이용한 경우와 추가적으로 아무것도 시행하지 않은 경우를 실험군으로 하였다. 레진 블록의 표면은 profilometer 및 SEM을 이용하여 거칠기 및 조도를 비교하였으며 통계분석 하였다. 실험 결과 mylar stirp을 적용한 경우 Ra (${\mu}m$) 평균 값은 ormocer-base composite resin이 $0.25{\mu}m$, ormocer-based flowable resin $0.17{\mu}m$, nanohybrid composite resin $0.24{\mu}m$, nanohybrid flowable resin $0.18{\mu}m$ 였으며 blade를 적용한 경우 평균 값은 각각 $0.43{\mu}m$, $0.37{\mu}m$, $0.48{\mu}m$, $0.41{\mu}m$ 였다. 가장 낮은 Ra (${\mu}m$)은 mylar stirp을 적용한 시편에서 얻어졌으며, blade를 이용한 마무리 방법과 rubber polishing을 시행한 경우와 표면 거칠기 비교시 Ra (${\mu}m$)값에서 통계적으로 유의한 차이를 보이지 않았다 (P>0.05). Nanohybrid composite resin이 blade로 마무리하거나 rubber polishing후 ormocer-based composite resin보다 표면 거칠기 증가율이 좀 더 큰 것을 알 수 있었다. 이상의 결과는 blade를 이용한 마무리 방법이 다른 마무리 방법을 대체할 수 있을 것이라는 것을 보여주며, 이에 따라 본 실험 결과에 한정지어 볼 때 복합레진 수복후 마무리 방법으로 blade를 이용하여 시행하는 것이 적용가능 할 것이라 생각된다.

• 대한치과보철학회지
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• 제44권3호
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• pp.333-342
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• 2006

Statement of problem. Although many studies have been carried out to investigate the correlation between the degree of conversion and the flexural strength of composite resins, there is minimal information in the literature attempting to compare degree of conversion, flexural strength and their correlation between restorative composite resins and flowable composite resins. Purpose. The purposes of this study were to measure the degree of conversion and flexural strength of composite resins with different rheological behavior and to correlate the two properties. Materials and methods. Four restorative (Vit-1-escence, Z-250, Tetric ceram, Esthet-X) and four flowable (Aeliteflo, Admiraflow, Permaflo, Revolution) light-curing composite resins were investigated. The degree of conversion(DC) was analyzed with Fourier transfer infra-red spectroscopy(FTIR) spectrum by a potassium bromide(KBr) pellet transmission method. The spectrum of the unpolymerized specimen had been measured before the specimen was irradiated for 60s with a visible light curing unit. The Poiymerized specimen was scanned for its in spectrum. The flexural strength(FS) was measured with 3-point bending test according to ISO 4049 after storage in water at $37^{\circ}C$ for 24 hours. The data were statistically analyzed by an independent sample t-test and one-way ANOVA at the significance level of 0.05. The dependence of flexural strength on the degree of conversion was also analyzed by regression analysis. Results. Mean DC and FS values ranged from 43% to 61% and from 84.7MPa to 156.7MPa respectively. DC values of the flowable composite resins were significantly higher than those of restorative composite resins (P < 0.05). The FS values of restorative composite resins were greater than those of flowable composite resins. No statistically significant correlation was observed between the DC and the FS tested in any of the composites. The dependence of FS on DC in restorative or flowable composite resins was not significant. Conclusion. It can be concluded that radical polymerization of the organic matrix is not a major factor in determining flexural strength of the commercially available composite resins.

• Restorative Dentistry and Endodontics
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• 제26권4호
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• pp.316-325
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• 2001

The purpose of this study was to evaluate the effect of adhesive curing timing on the direction of polymerization shrinkage of light-curing composite resin. In this study, the curing times of adhesive and composite resin were measured by differential scanning calorimeter(DSC). 28 extracted human molars were embedded in clear resin and box-type cavities were prepared. Based on DSC data, the experimental teeth were divided into 4 groups. Group 1: no bond; Group 2: late curing; Group 3: Intermediate curing; Group 4: Early curing. After treating with adhesive, the buccal cavities were filled with Z-100 hybrid composite resin and the lingual ones were filled with AEliteflo flowable composite resin. The depressions at the surface were measured by surface profilometer, then the specimens were embedded in clear resin and sectioned. Impressions were obtained and used to get epoxy resin replicas. The epoxy replicas were gold-coated and observed under SEM. Average Maximum Gap(AMG), Gap Proportion(GP), Average Marginal Index(AMI) were used to compare the shrinkage gap of each group. The results were statistically analyzed using the Kruskal-Wallis One Way ANOVA, Student-Newman-Keuls method. The results of this study were as follows. 1. Average Maximum Gap, Gap Proportion, Average Marginal Index and depression at the surface or Z-100 hybride composite resin were smaller than those of AEliteflo flowable composite resin(P<0.05). 2. When the bonding between composite resin and tooth structure was strong, the shrinkage gap was small, and depression at the surface was deep(P<0.05). 3. In the well-bonded group, light-curing composite resin shrank toward bonded cavity wall, not toward light source. The result suggested that the direction of polymerization shrinkage was affected by the quality of bonding in the dentin-resin interface. The strong was the bonding between composite resin and tooth structure, the smaller was the gap and the deeper was the depression at the surface. Then the flow to compensate the polymerization shrinkage proceeded from surface to bonded cavity wall.

• Restorative Dentistry and Endodontics
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• 제27권3호
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• pp.249-256
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• 2002

The use of flowable composite resins as liners in class II packable composite restoration has been suggested by some manufacturers. However, the contributions of this technique are unproven. The purpose of this study was to compare the gingival microleakage in class II packable composite restorations with or without the use of flowable composite resins as liners. Slot cavities were prepared on both proximals of 80 extracted human molars and randomly assigned to 8 groups of 20 each. The gingival margins were located at 1mm above CEJ in 80 cavities (group1-4) and 1mm below CEJ in 80 cavities (group5-8). The prepared teeth were mounted in the customized tray with adjacent teeth to simulate clinical conditions and metallic matrix band (Sectional matrix) and wooden wedges were applied. After acid etching and application of Single Bond, each group was restored with the following materials using incremental placement technique: Group 1,5 (Filtek P60), group 2, 3, 4 and group 6, 7, 8 (AeliteFlo, TetricFlow, Revolution/ Filtek P60). All specimens were thermocycled 500 times between 5$^{\circ}C$ and 55$^{\circ}C$ with 1 mimute dwell time, immersed 2% methylene blue dye for 24 hours and then rinsed with tab water. The specimens were embedded in clear resin and sectioned longitudinally through the center of restoration with a low speed diamond saw. Dye penetration at gingival margin was viewed at 20 magnification and analyzed on a scale of 0 to 4. Kruscal-Wallis One way analysis and Mann-Whitney Rank sum test were used to analyze the results. The results of this study were as follows. 1. The leakage values seen at the enamel margin were significantly lower than those seen at the dentin margin(P<0.05). 2. On the enamel margin, packable composite resins with flowable liners showed lower leakage than those without flowable liners, but there were no significant differences among the four groups(P>0.05). 3. On the dentin margin, four groups demonstrated moderate to severe leakage, and there were no significant differences in leakage values(P>0.05).