• The Journal of Advanced Prosthodontics
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• 제12권4호
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• pp.189-196
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• 2020

PURPOSE. The aim of the present study was to investigate the effects of surface treatments on the bond strengths between polymer-containing restorative materials and two dual-cure resin cements. MATERIALS AND METHODS. In the present study, rectangular samples prepared from Lava Ultimate (LU) and Vita Enamic (VE) blocks were used. The specimen surfaces were treated using CoJet sandblasting, 50 ㎛ Al₂O₃ sandblasting, % 9 HF (hydrofluoric) acid, ER,Cr:YSGG laser treatment, and Z-Prime. Dual-cure resin cements (TheraCem and 3M RelyX U 200) were applied on each specimen's treated surface. A micro-tensile device was used to evaluate shear bond strength. Statistical analysis was performed using the SAS 9.4v3. RESULTS. While the bond strength using TheraCem with LU or VE was not statistically significant (P=.164), the bond strength using U200 with VE was statistically significant (P=.006). In the TheraCem applied VE groups, Z-Prime and HF acid were statistically different from CoJet, Laser, and Sandblast groups. In comparison of TheraCem used LU group, there was a statistically significant difference between HF acid and other surface treatments. CONCLUSION. The bonding performance between the restorative materials and cements were material type-dependent and surface treatment had a large effect on the bond strength. Within the limitations of the study, the use of both U200 and TheraCem may be suggested if Z-prime was applied to intaglio surfaces of VE. The cementation of LU using TheraCem is suitable after HF acid conditioning of the restoration surfaces.

• Restorative Dentistry and Endodontics
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• 제41권4호
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• pp.271-277
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• 2016

Objectives: In this study, we evaluated the influence of different radiant exposures provided by single-peak and polywave light-curing units (LCUs) on the degree of conversion (DC) and the mechanical properties of resin cements. Materials and Methods: Six experimental groups were established for each cement (RelyX ARC, 3M ESPE; LuxaCore Dual, Ivoclar Vivadent; Variolink, DMG), according to the different radiant exposures (5, 10, and $20J/cm^2$) and two LCUs (single-peak and polywave). The specimens were made (7 mm in length ${\times}$ 2 mm in width ${\times}$ 1 mm in height) using silicone molds. After 24 hours of preparation, DC measurement was performed using Fourier transform infrared spectrometry. The same specimens were used for the evaluation of mechanical properties (flexural strength, FS; elastic modulus, E) by a three-point bending test. Data were assessed for normality, after which two-way analysis of variance (ANOVA) and post hoc Tukey's test were performed. Results: No properties of the Variolink cement were influenced by any of the considered experimental conditions. In the case of the RelyX ARC cement, DC was higher when polywave LCU was used; FS and E were not influenced by the conditions evaluated. The LuxaCore cement showed greater sensitivity to the different protocols. Conclusions: On the basis of these results, both the spectrum of light emitted and the radiant exposure used could affect the properties of resin cements. However, the influence was material-dependent.

• Restorative Dentistry and Endodontics
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• 제47권3호
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• pp.32.1-32.11
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• 2022

Objectives: This study aimed to evaluate the influence of inorganic composition and filler particle morphology on the mechanical properties of different self-adhesive resin cements (SARCs). Materials and Methods: Three SARCs including RelyX Unicem-2 (RUN), Maxcem Elite (MAX), and Calibra Universal (CAL) were tested. Rectangular bar-shaped specimens were prepared for flexural strength (FS) and flexural modulus (FM) and determined by a 3-point bending test. The Knoop microhardness (KHN) and top/bottom microhardness ratio (%KHN) were conducted on the top and bottom faces of disc-shaped samples. Sorption (Wsp) and solubility (Wsl) were evaluated after 24 hours of water immersion. Filler morphology was analyzed by scanning electron microscopy and X-ray energy dispersive spectroscopy (EDS). FS, FM, %KHN, Wsp, Wsl, and EDS results were submitted to 1-way analysis of variance and Tukey's post-hoc test, and KHN also to paired t-test (α = 0.05). Results: SARC-CAL presented the highest FS value, and SARC-RUN presented the highest FM. SARC-MAX and RUN showed the lowest Wsp and Wsl values. KHN values decreased from top to bottom and the SARCs did not differ statistically. Also, all resin cements presented carbon, aluminum, and silica in their composition. SARC-MAX and RUN showed irregular and splintered particles while CAL presented small and regular size particles. Conclusions: A higher mechanical strength can be achieved by a reduced spread in grit size and the filler morphology can influence the KHN, as well as photoinitiators in the composition. Wsp and Wsl can be correlated with ions diffusion of inorganic particles.

• 대한치과재료학회지
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• 제45권4호
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• pp.233-242
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• 2018

본 연구의 목적은 레진시멘트 색상이 상용 지르코니아 크라운의 색상에 미치는 영향을 평가하는 것이다. 연구에는 $NuSmile^{(R)}$ ZR Zirconia LT Shade (LT) 지르코니아와 $RelyX^{TM}$ U200 TR, A2, A3O (TR, A2, A3O) 레진시멘트를 사용했다. 이 때 지르코니아와 레진시멘트 시편은 직경 5 mm, 두께 1 mm의 디스크 형으로 각 조건 당 다섯 개씩 제작했다. CIE $L^*a^*b^*$값은 검은색과 흰색 배경에서 분광 광도계를 사용해 지르코니아와 레진시멘트 단독 조건과 겹친 조건에서 각각 측정했다. 레진시멘트 색상이 상용 지르코니아 크라운의 색상에 미치는 영향은 측정된 값을 이용해, 반투명도(TP, translucency parameter), 대조비(CR, contrast ratio), 색차(${\Delta}E{^*}_{ab}$)의 계산을 통해 평가했다. 각 변수에 대한 평균값과 표준편차는 동일한 실험군에서 CIE $L^*a^*^b^*$ 값을 3회씩 측정하여 구했다. 실험군의 통계적 유의성은 일원배치 분산분석(one-way ANOVA)과 Tukey-multiple comparisons test로 검증했다. 그 결과, 지르코니아 하방에 레진시멘트를 겹친 조건일 때는 지르코니아 단독 조건일 때에 비해 반투명도는 감소했고(p<0.05) 대조비는 증가했다. 검은색 배경에서 지르코니아와 지르코니아 하방에 레진시멘트를 겹쳤을 때의 색차는 모든 실험군에서 색의 변화를 인지할 수 없었고 LT/A3O 조합에서 최소값을 보였다. 한편, 흰색 배경에서 지르코니아와 지르코니아 하방에 레진시멘트를 겹쳤을 때의 색차는 LT/TR 조합에서 색변화를 임상적으로 허용할 수 있는 경계값을 보였다. LT/A2 조합에서는 색변화를 임상적으로 허용할 수 없었고, LT/A3O 조합에서는 색변화를 인지할 수 있었으나 임상적으로 허용할 수 있는 수준이었다. 이상의 결과와 같이 본 연구의 한계 내에서는, 흰색 배경의 LT/A2 조합 외에는 지르코니아 색상에 임상적으로 허용할 수 없는 색변화를 주는 레진시멘트는 없었다. 그 중 지르코니아 색상에 최소한의 영향을 미치는 레진시멘트 색상은 A3O였다. 따라서, 본 연구와 동일한 상용 지르코니아 크라운을 치아에 접착할 때 색변화를 최소화하기 위해서는 A3O 색상의 레진시멘트 사용이 추천된다.

• 대한치과의사협회지
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• 제53권3호
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• pp.195-200
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• 2015

Cementation is the last procedure and an important factor to access successful fixed prosthodontic treatment. Even though there are many kinds of luting materials in dental field, the resin cements are popularly used in now. Metals, polymers and ceramics are used as a material of fixed dental prosthesis. The bonding mechanisms between teeth and fixed restorations are composed of mechanical and chemical mechanism. In dentistry, we are relying on mechanical bonding, but we tried to get chemical bonding and many ways are introduced. So, we have to approach luting procedure differently by the materials of prosthesis for clinical success. In this article, let us think the proper cementation ways according to each prosthesis material.

• 대한치과보철학회지
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• 제35권3호
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• pp.504-516
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• 1997

Ultrasonic instruments transfer electrical energy to mechanical energy resulting in vibration used for various dental treatments. If we could know the effect of ultrasonic instruments on the dental cements within the cast crown, we could take care when conducting periodontal surgery and when using the ultrasonic instrument to remove cast crown, it would be much more convenient. The purpose of this study was to compare the bond strength of several dental cements according to ultrasonic instrumentation time. In this study 4 types of cements were used to cement the specimens. they were treated with ultrasonic instrumentation for 0-5 minutes and the change in bond strength were statistically compared. The results were as followed. 1. The tensile bond strength of zinc phosphate cement decreased according to the increase in time of ultrasonic instrument and showed significant difference between 0 minutes and the others and between 1 minute and 2,3,4,5 minutes (p<0.05). 2. The tensile bond strength of polycarboxylate cement decreased according to the increase in time of ultrasonic instrument and showed significant difference between 5 minutes and the others and between 4 minutes and 0 minutes (p<0.05). 3. The tensile bond strength of zinc phosphate cement decreased according to the increase in time of ultrasonic instrument and showed significant difference between 5 minutes and the others (p<0.05). 4. The tensile strength of resin cements showed no statistically differences according to the ultrasonic instrumentation time. In conclusion, it is considered that zinc phosphate cements is most affected by ultrasonic instrumentations and resin cement is the least affected. When using ultrasonic instruments the result avove should be used as an index.

• 대한치과보철학회지
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• 제29권1호
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• pp.91-109
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• 1991

The purpose of this study were to comfirm the effects of the thickness and kinds of porcelain, etchants, illumination time, elapsed time for the measurement, and chemical cure component to the bond strength of porcelain laminate and composite resin cement, and to compare the effects between the light cured resin and the dual cured resins. The etched porcelain surface, the sectioned surface crossing porcelain and resin after bonding, and the debonded surfaces were observed by the SEM. One product of laminate porcelain powder, one light cured resin and two dual cured resins were selected. Each resin cements are lightened through the thin porcelain disc which was cut from cylindrical porcelain specimen by the diamond saw, and by the light through the porcelain disc they were bonded. Changes of thickness and kinds of porcelain, etchants, illumination time, and the elapsed time for the measurement were considered as variables for the bond strength. And the bond strength of porcelain and dual cured resins under the conditions of autopolymerization or the removal of chemical cure component were measured and compared. Bond strength were measured by shear stress. The etched surface, the cross-sectioned surface, and the debonded surface of porcelain or resin were observed by SEM. On the summary of this study, the following conclusions can be stated; 1. Bond strength of light cured resin was decreased inversely by the thickened porcelain laminate and showed the lowest value to the masking dentin porcelain among 4 kinds of porcelain powder. 2. Bond strength of autopolymerization of dual cured resin without illumination in dark chamber were from 75% to 98% to the data of dual cured resin with illumination. 3. Bond strength of dual cured resin used without chemical cured components were same to them of light cured resin. 4. Cross-sectioned surface treated by silane did not show the gap between the porcelain and resin. 5. Illumination over 80 seconds did not make the significant increase of bond strength on all kinds of resin.

• 대한치과보철학회지
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• 제38권2호
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• pp.169-177
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• 2000

The purpose of this study was to compare the retention of complete cast crown over amalgam ores, composite resin cores, and cast gold cores when cemented with three different luting agents. Eighteen core specimens each of amalgam(Bestaloy, Dong Myung, Seoul, Korea), composite resin (Z100, 3M Dental product, st. Paul, Minn) and type IV gold alloy (Ba-4, Heesung Engelhard Corp., Korea) were made in a customized milling stainless steel die. A wax pattern with a loop attached to occlusal surface was made for each core and a type II gold alloy casting was fabricated. The castings which had clinically acceptable marginal fit were used as test samples. The following luting cements were used to cement cast crowns on each core material : (1) zinc phosphate cement (Confi-dental Products Co., USA) (2) glass-ionomer cement (Fuji Plus, GC Industrial Corp., Tokyo, Japan) (3) resin cement (Panavia 21, Kuraray Co., USA). All cements were mixed according to manufacturers' instructions. A static load of 5kg was then applied for 10 minutes on the crowns. All specimens were stored in saline solution for 24 hours at $37^{\circ}C$ and thermocycled for 500 cycles. After storage and cycling, the tensile bond strengths were measured by using a universal testing machine (Instron Corp., Canton, Mass.) at a crosshead speed of 0.5mm/min. The results were as follows 1. The retentive strength of resin cement was the highest of alt three types of cement for resin core (p<0.05). 2. There was no statistical difference among the retentive strengths of three cements for amalgam core (p>0.05). 3. The retentive strength of resin cement was higher than that of zinc phosphate for cast core, but there was no difference between the retentive strength of glass ionomer cement and those of rein and zinc phosphate cement. 4. The retentive strength of the zinc phosphate cement for amalgam core was the highest of all type of cores.

• 대한치과보철학회지
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• 제45권6호
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• pp.743-752
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• 2007

Statement of problem. The aims of the study were to evaluate the effect of current surface conditioning methods on the bond strength of a resin composite luting cement bonded to ceramic surfaces and to identify the optimum cement type. Material and methods. The sixty zirconia ceramic specimens(10 per group) with EVEREST milling machine and 60 tooth block were made. The zirconia ceramic surface was divided into two groups according to surface treatment: (1) airborne abrasion with $110{\mu}m$ aluminum oxide particles; (2) Rocatec system, tribochemical silica coating. The zirconia ceramic specimens were cemented to tooth block using resin cements. The tested resin cements were Rely X ARC, Panavia F and Superbond C&B. Each specimen was mount in a jig of the universal testing machine for shear strength. The results were subjected to 2-way ANOVA and Post hoc tests was performed using Tukey, Scheffe, and Bonferroni test. Results. The mean value of shear bond strength(MPa) were as follows: $$RelyXARC(+Al_2O_3),5.35{\pm}1.69$$; $$RelyXARC(+Rocatec),8.50{\pm}2.13$$; $$PanaviaF(+Al_2O_3),9.58{\pm}1.13$$; $$PanaviaF(+Rocatec),12.98{\pm}1.71$$; $$SuperbondC&B(+Al_2O_3)8.27{\pm}2.04$$; $$SuperbondC&B(+Rocatec),14.46{\pm}2.39$$. There was a significant increase in the shear bond strength when the ceramic surface was subjected to the tribochemical treatment(Rocatec 3M) in all cement groups(P<0.05). Bonding strengths of cements applied to samples treated with $Al_2O_3$ were compared; Rely X ARC showed the lowest values, whereas Panavia F cement showed higher value than that of Superbond C&B group with no statistical significance. When the bond strength of cements with of Rocatec treatment was compared, Rely X ARC showed lowest values. Overall, it was apparent that tribochemical treated Super-Bond possessed higher mean bond strength (14.46MPa; P<0.05) than that of Panavia F cement group with no significance. Conclusions. Silica coating followed silanization(Rocatec treatment) increase the bond strength between resin cement and zirconia ceramic. Panavia F containing phosphate monomer and Superbond C&B comprised of 4-META tend to bond chemically with zirconia ceramic, thus demonstrating higher bond strength compared to BisGMA resin cement. Superbond C&B has shown to have highest value of bonding strength to zirconia ceramic after Rocatec treatment compared to other cement.

• Restorative Dentistry and Endodontics
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• 제34권2호
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• pp.103-112
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• 2009

본 연구에서는 2종의 이원중합 레진시멘트 (RelyX ARC와 Variolink II)를 이용하여 접착제와 레진시멘트의 중합방법 (자가중합과 광중합)이 섬유포스트와 근관 상아질의 결합강도와 접착계면에 미치는 영향을 상호 비교하기 위하여 시행하였다. 단근관을 갖는 발거된 32개의 하악 소구치에 근관을 충전한 후, FRC Postec system의 Reamer로 9 mm 깊이의 포스트 공간을 형성하였다. 레진시멘트의 종류와 중합방법에 따라 4개의 군 (R-SC군, R-LC군, V-SC군, V-LC군)으로 분류하였다. 포스트 공간에 각 군의 접착제를 도포한 후 레진시멘트를 주입하고, No. 3 FRC Postec 포스트를 위치시켜 자가중합 또는 광중합시켰다. 각 군의 치근을 실온의 증류수에 24시간동안 보관한 다음, 저속의 diamond wheel saw를 이용하여 치관부에서 치근단부를 향해 1.5 mm두께로 연속적으로 횡절단하여 1개의 치근에서 3개의 절편을 얻었다. 각 군의 절편 (31개)은 만능시험기에서 push-out 검사를 시행하였고, 각 군의 강도 값은 반복측정 two-way ANOVA와 one-way ANOVA를 이용하여 비교 분석하였다. 각 군의 절편 (3개)은 주사전자현미경하에서 섬유포스트, 레진시멘트 및 치근 상아질 간의 계면을 관찰, 비교하였다. 본 연구의 결과 전 부식 레진시멘트를 이용하여 섬유포스트를 포스트 공간에 합착할 경우, 접착제와 레진시멘트의 중합방법은 근관 상아질의 결합강도에 영향을 주었으며, 광중합보다 자가중합 방법 이 우수한 결합강도와 계면을 나타내었다.