• Restorative Dentistry and Endodontics
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• v.25 no.1
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• pp.17-40
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• 2000

Resin cements are used for cementing indirect esthetic restorations such as resin or porcelain inlays. Because of its limitations in curing of purely light cured resin cements due to attenuation of the curing light by intervening materials, dual cured resin cements are recommended for cementing restorations. The physical properties of resin cements are greatly influenced by the extent to which a resin cures and the degree of cure is an important factor in the success of the inlay. The purpose of this study was to evaluate the influence of porcelain thickness and exposure time on the polymerization of resin cements by measuring the microhardness and the degree of conversion, to investigate the nature of the correlation between two methods mentioned above, and to determine the exposure time needed to harden resin cements through various thickness of porcelain. The degree of resin cure was evaluated by the measurements of microhardness [Vickers Hardness Number(VHN)] and degree of conversion(DC), as determined by Fourier Transform Infrared Spectroscopy(FTIR) on one light cured composite resin [Z-100(Z)] and three dual cured resin cements [Duo cement(D), 3M Resin cement(R), and Dual cement(DA)] which were cured under porcelain discs thickness of 0mm, 1mm, 2mm, 3mm with light exposure time of 40sec, 80sec, 120sec, and regression analysis was performed to determine the correlation between VHN and DC. In addition, to determine the exposure time needed to harden resin cements under various thickness of porcelain discs, the changes of the intensity of light attenuated by 1mm, 2mm, and 3mm thickness of porcelain discs were measured using the curing radiometer. The results were obtained as follows ; 1. The values of microhardness and the degree of conversion of resin cements without intervening porcelain discs were 31~109VHN and 51~63%, respectively. In the microhardness Z was the highest, followed by R, D, DA. In the degree of conversion, D and DA was significantly greater than Z and R(p<0.05). 2. The microhardness and the degree of conversion of the resin cements decreased with increasing thickness of porcelain discs, and increased with increasing exposure time, D and R showed great variation with inlay thickness and exposure time, whereas, DA showed a little variation. 3. The intensity of light through 1mm, 2mm, and 3mm porcelain inlays decreased by 0.43, 0.25, and 0.14 times compared to direct illumination, and the respective needed exposure times are 53 sec, 70 sec, and 93 sec. In D and R, 40 sec of light irradiation through 2mm porcelain disc and 80 sec of light irradiation through 3mm porcelain disc were not enough to complete curing. 4. The microhardness and the degree of conversion of the resin cements showed a positive correlationship(R=0.791~0.965) in the order of R, D, Z, DA. As the thickness of porcelain discs increased, the decreasing pattern of microhardness was different from that of the degree of conversion, however.

• The Journal of Advanced Prosthodontics
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• v.13 no.4
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• pp.246-257
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• 2021

PURPOSE. This study aimed to investigate the Vickers Hardness Number (VHN) of light- and dual cured resin cements cured through monolithic zirconia specimens (VITA YZ) of various translucencies: translucent (T); high translucent (HT); super translucent (ST); and extra translucent (XT) at 0, 24, and 48 h after curing. MATERIALS AND METHODS. Four zirconia specimens from each translucency were prepared. Two light-cured resin cements (Variolink N LC; VL and RelyX Veneer; RL) and two dual-cured resin cements (Variolink N DC; VD and RelyX U200; RD) were used. The cement was mixed and loaded in a mold and cured for 20 s through the zirconia specimen. The upper surface of cements was tested for VHN using a microhardness tester at 0, 24, and 48 h after curing. The VHN were analyzed using two-way repeated, Brown-Forsythe ANOVA with Games Howell post-hoc analysis and independent t-tests (P < .05). RESULTS. All cements showed significantly higher VHN from 0 h to 24 h (P < .001). At 48 h, the VHN of light-cured cements were significantly lower when cured under the T groups than under XT groups (P = .001 in VL, P = .014 in RL). At each post curing time of each translucency, VD showed higher VHN than VL (P < .05), and RD also showed higher VHN than RL (P < .05). CONCLUSION. The translucency of zirconia has an effect on the VHN for light-cured resin cements, but has no effect on dual-cured resin cements. Dual-cured resin cement exhibited higher VHN than the light-cured resin cement from the same manufacturer. All resin cements showed significantly higher VHN from 0 h to 24 h.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.1
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• pp.1-14
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• 2005

Statement of problem. Among the physical properties of adhesion luting cement, the aspect that requires the most important factor is the degree of solubility and water sorption. Dissolution or an inadequate due to excessive water sorption inside the oral cavity compromises the while concurrently increasing the susceptibility to secondary dental caries. Susceptibility to dissolution and difficulty of removing remnant cement from the gingival sulcus have hindered the use of dental resin cement in the clinical practice, but the improved characteristics of newer generation resin cements have interest in and enabled resin cements to be widely used in adhesion of fixed prosthesis, such as laminate veneers and all-ceramic crowns. Purpose. The purpose of this study is to compare and analyze the degrees of solubility and water sorption of a variety of resin cements widely used for clinical purposes with different curing methods. Material and methods. Self-curing resin cements, $Avanto^{(R)}$, $C&B^{TM}$ CEMENT and Superbond C&B cements comprised group 1, 2 and 3. The dual-curing resin cements $Panavian^{TM}$ F, $Calibra^{(R)}$ and $Variolink^{(R)}$ II were divided into groups 4, 5, and 6, respectively. The investigation was carried out using disc-shaped specimens as specified by ANSI/ADA Specification No. 27. The degree of water sorption, water solubility and lactic acid solubility of each test group was analyzed statistically leading to the following conclusion. Results. The degree of water sorption was shown to increase in the following order : group 6, 5, 4, 2, 1 and 3. There were significant differences between the water sorption of each group. Results of the degree of water solubility were shown to increase in the following order : group 6, 5, 4, 2, 1 and 3. Statistically significant differences were found between each group, with the exception of groups 1 and 3. Finally, the degree of lactic acid solubility was found to increase in the following order : group 6,5,4,2,3 and 1. Significant differences were found between each group. In general dual-curing resin cements displayed substantially lower values than self-curing resin cements with regard to water sorption, water solubility, and lactic acid solubility. Conclusions. From the results of this study, dual-curing resin cements show a significantly lower degree of water sorption and solubility than their self-curing counterparts. Clinically, when selecting resin cements, the product with a lower degree of water sorption and solubility are preferred. The results of this study indicate that the use-of dual-curing resin cements is preferable to self-curing cements.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.2
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• pp.111-127
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• 2003

Statement of problem : Resin cements were used widely on all ceramic crowns, but the influence of resin cements on biocells was not understood clearly. Purpose : This study was investigated to evaluate the biocompatibility of resin cements for all-ceramic crowns. Material and Method : The resin cements used in this study were Panavia F (Kuraray Co., Ltd. Japan), Variolink II (Vivadent Ets., Schann / Liechtenstein), and Bistite II (Bistite dual cure resin cement-clear Tokuyama Soda Co. Japan). The viability of normal human oral keratocytes, gingival fibroblast, and gingival fibroblast immortalized by Human Papilloma virus 16 was measured in vitro for evaluation of cytotoxicity on resin cements, and the response of pulp tissue was analyzed and evaluated with light microscope after application of cements at cutting edge of incisors. Results : The normal human oral keratocytes was the most sensitive to toxicity of resin cement, and toxicity of cements was higher in Bistite II than in Variolink II. The cell viability of immortalized gingival fibroblast did not affected by type of cement and cultivation period, but there was a tendency that cytotoxicity in Bistite II was higher than in Variolink II. The cell viability of gingival fibroblast was similar to that of immortalized gingival fibroblast regardless of cement type, but Bistite II showed more toxic than others after 5 days cultivation. The responses of pulp tissue according to cement type were similar after 2 days cultivation, but revealed high toxicity in Bistite II after 10 days cultivation. Conclusion : Variolink II was more biocompatible than any other resin cements used in this study.

• Restorative Dentistry and Endodontics
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• v.44 no.4
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• pp.45.1-45.10
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• 2019

Objectives: Self-adhesive resin cements contain functional monomers that enable them to adhere to the tooth structure without a separate adhesive or etchant. One of the most stable functional monomers used for chemical bonding to calcium in hydroxyapatite is 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP). The aim of this study was to evaluate the influence of the10-MDP concentration on the bond strength and physical properties of self-adhesive resin cements. Materials and Methods: We used experimental resin cements containing 3 different concentrations of 10-MDP: 3.3 wt% (RC1), 6.6 wt% (RC2), or 9.9 wt% (RC3). The micro-tensile bond strength of each resin cement to dentin and a hybrid resin block (Estenia C&B, Kuraray Noritake Dental) was measured, and the fractured surface morphology was analyzed. Further, the flexural strength of the resin cements was measured using the three-point bending test. The water sorption and solubility of the cements following 30 days of immersion in water were measured. Results: The bond strength of RC2 was significantly higher than that of RC1. There was no significant difference between the bond strength of RC2 and that of RC3. The water sorption of RC3 was higher than that of any other cement. There were no significant differences in the three-point bending strength or water solubility among all three types of cements. Conclusions: Within the limitations of this study, it is suggested that 6.6 wt% 10-MDP showed superior properties than 3.3 wt% or 9.9 wt% 10-MDP in self-adhesive resin cement.

• Restorative Dentistry and Endodontics
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• v.35 no.2
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• pp.69-79
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• 2010

The purpose of this study was to evaluate the effect of film thickness of various resin cements on bonding efficiency in indirect composite restoration by measurement of microtensile bond strength, polymerization shrinkage, flexural strength and modulus, fractographic FE-SEM analysis. Experimental groups were divided according to film thickness (< $50\;{\mu}m$-control, $50\;{\mu}m$-T50, $100\;{\mu}m$-T100, $150\;{\mu}m$-T150) using composite- based resin cements (Variolink II, Duo-Link) and adhesive-based resin cements (Panavia F, Rely X Unicem). The data was analyzed using ANOVA and Duncan's multiple comparison test (p < 0.05). The results were as follows ; 1. Variolink II showed higher microtensile bond strength than that of adhesive-based resin cements in all film thickness (p < 0.05) but Duo-Link did not show significant difference except control group (p > 0.05). 2. Microtensile bond strength of composite-based resin cements were decreased significantly according to increasing film thickness (p < 0.05) but adhesive-based resin cements did not show significant difference among film thickness (p > 0.05). 3. Panavia F showed significantly lower polymerization shrinkage than other resin cements (p < 0.05). 4. Composite-based resin cements showed significantly higher flexural strength and modulus than adhesive-based resin cements (p < 0.05). 5. FE-SEM examination showed uniform adhesive layer and well developed resin tags in composite-based resin cements but unclear adhesive layer and poorly developed resin tags in adhesive-based resin cements. In debonded surface examination, composite-based resin cements showed mixed failures but adhesive-based resin cements showed adhesive failures.

• The Journal of Advanced Prosthodontics
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• v.8 no.2
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• pp.144-149
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• 2016

PURPOSE. The use of temporary or permanent cements in fixed implant-supported prostheses is under discussion. The objective was to compare the retentiveness of one temporary and two permanent cements after cyclic compressive loading. MATERIALS AND METHODS. The working model was five solid abutments screwed to five implant analogs. Thirty Cr-Ni alloy copings were randomized and cemented to the abutments with one temporary (resin urethane-based) or two permanent (resin-modified glass ionomer, resin-composite) cements. The retention strength was measured twice: once after the copings were cemented and again after a compressive cyclic loading of 100 N at 0.72 Hz (100,000 cycles). RESULTS. Before loading, the retention strength of resin composite was 75% higher than the resin-modified glass ionomer and 2.5 times higher than resin urethane-based cement. After loading, the retentiveness of the three cements decreased in a non-uniform manner. The greatest percentage of retention loss was shown by the temporary cement and the lowest by the permanent resin composite. However, the two permanent cements consistently show high retention values. CONCLUSION. The higher the initial retention of each cement, the lower the percentage of retention loss after compressive cyclic loading. After loading, the resin urethane-based cement was the most favourable cement for retrieving the crowns and resin composite was the most favourable cement to keep them in place.

• The Journal of Advanced Prosthodontics
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• v.9 no.1
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• pp.57-66
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• 2017

PURPOSE. Cementation failures of restorations are frequently observed in clinical practice. The purpose of this study is to compare the effect of initial and repeated bonding on the bond strengths of different resin cements to enamel and dentin. MATERIALS AND METHODS. Ninety human maxillary central incisors were bisected longitudinally. The 180 tooth halves were divided into 2 groups (n = 90) for enamel and dentin bonding. The enamel and dentin groups were further divided into 3 groups (n = 30) for different resin cement types. Composite resin (Filtek Ultimate) cylinders ($3{\times}3\;mm$) were prepared and luted to enamel and dentin using Variolink II (Group V), RelyX ARC (Group R), or Panavia F 2.0 (Group P) resin cement. After 24 hours, initial shear bond strengths of the resin cements to enamel and dentin were measured. Using new cylinders, the specimens were de-bonded and re-bonded twice to measure the first and the second bond strengths to enamel and dentin. Failure modes and bonding interfaces were examined. Data were statistically analyzed. RESULTS. Initial and repeated bond strengths to enamel were similar for all the groups. The first ($15.3{\pm}2.2\;MPa$) and second ($10.4{\pm}2.2\;MPa$) bond strengths to dentin were significantly higher in Group V (P<.0001). Second bond strengths of dentin groups were significantly lower than initial and first bond strengths to dentin (P<.0001). CONCLUSION. All resin cements have similar initial and repeated bond strengths to enamel. Variolink II has the highest first and second bond strength to dentin. Bond strength to dentin decreases after the first re-bonding for all resin cements.

• Restorative Dentistry and Endodontics
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• v.43 no.4
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• pp.40.1-40.10
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• 2018

Objectives: This study evaluated the microtensile bond strength (${\mu}TBS$) of polymer-ceramic and indirect composite resin with 3 classes of resin cements. Materials and Methods: Two computer-aided design/computer-aided manufacturing (CAD/CAM)-fabricated polymer-ceramics (Enamic [ENA; Vita] and Lava Ultimate [LAV; 3M ESPE]) and a laboratory indirect composite resin (Gradia [GRA; GC Corp.]) were equally divided into 6 groups (n = 18) with 3 classes of resin cements: Variolink N (VAR; Vivadent), RelyX U200 (RXU; 3M ESPE), and Panavia F2 (PAN; Kuraray). The ${\mu}TBS$ values were compared between groups by 2-way analysis of variance and the post hoc Tamhane test (${\alpha}=0.05$). Results: Restorative materials and resin cements significantly influenced ${\mu}TBS$ (p < 0.05). In the GRA group, the highest ${\mu}TBS$ was found with RXU ($27.40{\pm}5.39N$) and the lowest with VAR ($13.54{\pm}6.04N$) (p < 0.05). Similar trends were observed in the ENA group. In the LAV group, the highest ${\mu}TBS$ was observed with VAR ($27.45{\pm}5.84N$) and the lowest with PAN ($10.67{\pm}4.37N$) (p < 0.05). PAN had comparable results to those of ENA and GRA, whereas the ${\mu}TBS$ values were significantly lower with LAV (p = 0.001). The highest bond strength of RXU was found with GRA ($27.40{\pm}5.39N$, p = 0.001). PAN showed the lowest ${\mu}TBS$ with LAV ($10.67{\pm}4.37N$; p < 0.001). Conclusions: When applied according to the manufacturers' recommendations, the ${\mu}TBS$ of polymer-ceramic CAD/CAM materials and indirect composites is influenced by the luting cements.

• Restorative Dentistry and Endodontics
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• v.49 no.2
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• pp.18.1-18.13
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• 2024

Objectives: This study was conducted to evaluate the mechanical properties of relined and non-relined fiberglass posts when cemented to root canal dentin using a conventional dual-cure resin cement or a self-adhesive resin cement. Materials and Methods: Two types of resin cements were utilized: conventional and self-adhesive. Additionally, 2 cementation protocols were employed, involving relined and non-relined fiberglass posts. In total, 72 bovine incisors were cemented and subjected to push-out bond strength testing (n = 10) followed by failure mode analysis. The cross-sectional microhardness (n = 5) was assessed along the root canal, and interface analyses (n = 3) were conducted using scanning electron microscopy (SEM). Data from the push-out bond strength and cross-sectional microhardness tests were analyzed via 3-way analysis of variance and the Bonferroni post-hoc test (α= 0.05). Results: For non-relined fiberglass posts, conventional resin cement exhibited higher pushout bond strength than self-adhesive cement. Relined fiberglass posts yielded comparable results between the resin cements. Type II failure was the most common failure mode for both resin cements, regardless of cementation protocol. The use of relined fiberglass posts improved the cross-sectional microhardness values for both cements. SEM images revealed voids and bubbles in the incisors with non-relined fiberglass posts. Conclusions: Mechanical properties were impacted by the cementation protocol. Relined fiberglass posts presented the highest push-out bond strength and cross-sectional microhardness values, regardless of the resin cement used (conventional dual-cure or self-adhesive). Conversely, for non-relined fiberglass posts, the conventional dual-cure resin cement yielded superior results to the self-adhesive resin cement.