• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.218-225
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• 2016

Purpose: The purpose of this study was to evaluate the push-out bond strength of glass-fiber post cemented with different adhesive systems and surface treatments. Materials and methods: 160 tooth samples made from 48 human maxillary single-rooted teeth with similar root length were divided into 4 groups according to the adhesive system (no adhesive, Adper Single Bond 2, Clearfil SE Bond, Clearfil S3). Each group had 4 subgroups according to the post surface treatment methods (no treatment, sandblast, silane, sandblast and silane). Posts (Parapost Fiber White) were cemented with Rely X Unicem. The teeth were sectioned perpendicular to their long axis into 1-mm thick sections. The push-out tests was performed at a speed of 0.5 mm/min. The results were evaluated by 2-way ANOVA, 1-way ANOVA and multiple comparison procedures (Tukey test) (${\alpha}=0.05$). Results: Tukey test showed that the adhesive system significantly influenced the push-out strength. The Clearfil SE Bond group showed the highest value. Post surface treatments showed no significant effect. Conclusion: Bond strength of glass-fiber post cemented with self-adhesive resin cement using Clearfil SE Bond showed significantly higher values compared to other adhesive systems.

• Restorative Dentistry and Endodontics
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• v.41 no.3
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• pp.167-175
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• 2016

Objectives: Endodontically treated teeth with insufficient tooth structure are often restored with esthetic restorations. This study evaluated the cytotoxicity and biological effects of yttria partially stabilized zirconia (Y-TZP) blocks in combination with several dental cements. Materials and Methods: Pairs of zirconia cylinders with medium alone or cemented with three types of dental cement including RelyX U200 (3M ESPE), FujiCEM 2 (GC), and Panavia F 2.0 (Kuraray) were incubated in medium for 14 days. The cytotoxicity of each supernatant was determined using 3-(4,5-dimethylthiazole- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays on L929 fibroblasts and MC3T3-E1 osteoblasts. The levels of interleukin-6 (IL-6) mRNA were evaluated by reverse transcription polymerase chain reaction (RT-PCR), and IL-6 protein was evaluated by enzyme-linked immunosorbent assays (ELISA). The data were analyzed using one-way ANOVA and Tukey post-hoc tests. A p < 0.05 was considered statistically significant. Results: The MTT assays showed that MC3T3-E1 osteoblasts were more susceptible to dental cements than L929 fibroblasts. The resin based dental cements increased IL-6 expression in L929 cells, but reduced IL-6 expression in MC3T3-E1 cells. Conclusions: Zirconia alone or blocks cemented with dental cement showed acceptable biocompatibilities. The results showed resin-modified glass-ionomer based cement less produced inflammatory cytokines than other self-adhesive resin-based cements. Furthermore, osteoblasts were more susceptible than fibroblasts to the biological effects of dental cement.

• The Journal of Advanced Prosthodontics
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• v.4 no.4
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• pp.192-196
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• 2012

PURPOSE. The purpose of this study was to evaluate the effect of provisional cement removal by different dentin cleaning protocols (dental explorer, pumice, cleaning bur, Er:YAG laser) on the shear bond strength between ceramic and dentin. MATERIALS AND METHODS. In total, 36 caries-free unrestored human third molars were selected as tooth specimens. Provisional restorations were fabricated and cemented with eugenol-free provisional cement. Then, disc-shaped ceramic specimens were fabricated and randomly assigned to four groups of dentin cleaning protocols (n = 9). Group 1 (control): Provisional cements were mechanically removed with a dental explorer. Group 2: The dentin surfaces were treated with a cleaning brush with pumice Group 3: The dentin surfaces were treated with a cleaning bur. Group 4: The provisional cements were removed by an Er:YAG laser. Self-adhesive luting cement was used to bond ceramic discs to dentin surfaces. Shear bond strength (SBS) was measured using a universal testing machine at a 0.05 mm/min crosshead speed. The data were analyzed using a Kolmogorov Smirnov, One-way ANOVA and Tukey HSD tests to perform multiple comparisons (${\alpha}$=0.05). RESULTS. The dentin cleaning methods did not significantly affect the SBS of ceramic discs to dentin as follows: dental explorer, pumice, cleaning bur, and Er:YAG laser. CONCLUSION. The use of different cleaning protocols did not affect the SBS between dentin and ceramic surfaces.

• The Journal of Advanced Prosthodontics
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• v.15 no.3
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• pp.136-144
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• 2023

PURPOSE. The study objective was to evaluate the influence of the type of resin cement on the flexural strength and load to fracture of two chairside CADCAM materials after aging. MATERIALS AND METHODS. A polymer-infiltrated ceramic network (PICN) and a nanoceramic resin (RNC) were used to produce the specimens. Two types of dual-cure resin cements, a self-adhesive and a universal, were investigated. Bilayer specimens were produced (n = 10) and aged for 6 months in a humid environment before the biaxial flexural strength test (σ_f). Bonded specimens were subjected to a mechanical aging protocol (50 N, 2 Hz, 37℃ water, 500,000 cycles) before the compressive load test (L_f). σ_f and L_f data were analyzed using two-way ANOVA and Tukey tests (α = .05). Chi-square test was used to analyze the relationship between failure mode and experimental group (α = .05). RESULTS. The type of resin cement and the interaction between factors had no effect on the σ_f and L_f of the specimens, while the type of restorative material was significant. RNC had higher σ_f and L_f than PICN. There was a significant association among the type of cracks identified for specimens tested in L_f and the restorative material. CONCLUSION. The type of resin cement had no effect on the flexural strength and load to fracture of the two investigated CAD-CAM chairside materials after aging.

• Restorative Dentistry and Endodontics
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• v.34 no.2
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• pp.103-112
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• 2009

The purpose of this study was to compare the effect of curing methods of adhesive resins and resin cements in the root canal. Crown portions of 32 single-rooted mandibular premolars were removed. Routine endodontic treatment was done, and 9 mm deep post spaces were prepared within root canals. No.3 FRC Postec posts (Ivoclar-Vivadent AG, Liechtensteih) were cemented in the post spaces by self-(SC) or light-curing (LC) using two dual-cured adhesives (Adper Scotchbond multi-purpose plus and Exite DSC )and resin cements (RelyX ARC and Variolink II). They were assigned to 4 groups (n=8): R-SC, R-LC, V-SC, V-LC group. After stored in distilled water for 24 hours, each root was transversally sectioned with 1.5 mm thick and made three slices. The specimens were subjected to push-out test in a universal testing machine (EZ Test, Shimadzu Co., Japan) with a crosshead speed of 1 mm/min. The data were analyzed with repeated ANOVA and one-way ANOVA. Also the interface of post-resin cement and resin cement-canal wall of each group was observed under FE-SEM. When fiber posts were cemented into the root canal using total-etch adhesives, the bond strength and adaptation between post and root canal dentin was affected by curing method. Self-cure of adhesives and resin cements showed higher bond strength and closer adaptation than light-cure of them.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.4
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• pp.359-365
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• 2013

The aim of this study was to evaluate the effect of temporary restorative and filling material on bonding strength between lithium disilicate glass-ceramic and dentin. 60 extracted human molars were cross-sectioned at occlusal third and were embedded into self-cure acrylic resin. Then the teeth were randomly divided into four groups of 15 each. Lithium disilicate glass-ceramic is cemented to dentin as follows: after no any application of the provisional materials (Group A), after application of ALIKETM (GC America Inc.)(Group B), after application of Luxatemp$^{(R)}$ Automix plus (DMG, Germany)(Group C), after application of Fermit$^{(R)}$ (Ivoclar Vivadent, Leichtenstein)(Group D). After the specimens were stored in distilled water for 24 hours, the shear bond strength of the specimens were measured using UTM (Zwick 1456 41, Zwick, Germany) at a crosshead speed of 1mm/min. The data were analysed by one-way ANOVA and Tukey HSD tests. There were no statistically significant differences of bond strength among the groups. Fracture type was showed mixed type of adhesive and cohesive fracture in most of specimens. Within the limitation of this study, bond strength of adhesive resin cement between lithium disilicate glass-ceramic and dentin was not affected by provisional restorative and filling materials.

• The Journal of Advanced Prosthodontics
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• v.10 no.5
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• pp.340-346
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• 2018

PURPOSE. In this study, the shear bond strengths (SBS) of luting cements to fixed superstructure metal surfaces under various seating forces were investigated. MATERIALS AND METHODS. Seven different cements [Polycarboxylate (PCC), Glass-Ionomer (GIC), Zinc phospahate (ZPC), Self-adhesive resin (RXU), Resin (C&B), and Temporary cements ((RXT) and (TCS))] were bonded to a total number of 224 square blocks ($5{\times}5{\times}3mm$) made of one pure metal [Titanium (CP Ti) and two metal alloys [Gold-Platinum (Au-Pt) and Cobalt-Chrome (Co-Cr)] under 10 N and 50 N seating forces. SBS values were determined and data were analyzed with 3-way ANOVA. Pairwise comparisons and interactions among groups were analyzed with Tukey's simultaneous confidence intervals. RESULTS. Overall mean scores indicated that Co-Cr showed the highest SBS values ($1.96{\pm}0.4$) (P<.00), while Au-Pt showed the lowest among all metals tested ($1.57{\pm}0.4$) (P<.00). Except for PCC/CP Ti, RXU/CP Ti, and GIC/Au-Pt factor level combinations (P<.00), the cements tested under 10 N seating force showed no significantly higher SBS values when compared to the values of those tested under 50 N seating force (P>.05). The PCC cement showed the highest mean SBS score ($3.59{\pm}0.07$) among all cements tested (P<.00), while the resin-based temporary luting cement RXT showed the lowest ($0.39{\pm}0.07$) (P<.00). CONCLUSION. Polycarboxylate cement provides reliable bonding performance to metal surfaces. Resin-based temporary luting cements can be used when retrievability is needed. GIC is not suitable for permanent cementation of fixed dental prostheses consisting of CP Ti or Au-Pt substructures.

• Journal of Korean Dental Science
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• v.1 no.1
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• pp.28-34
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• 2008

Objectives. The objectives of this study were: 1) to compare the effect of varying timing of light curing on shear bond strength, and; 2) to compare the shear bond strength of three self-adhesive cements. Materials and methods. A total of 72 extracted non-carious teeth were divided into 24 for Unicem tests, 24 for Maxcem tests, and 24 for Biscem tests; they were assigned 3 * 2 subgroups of 12 teeth each. The specimens were prepared as follows: 1) The calculus and periodontal ligament were removed from the teeth; 2) The teeth were stored in normal saline; 3) The occlusal enamel of each tooth was removed using high-speed coarse diamond burs under water cooling, and; 4) Finally, the teeth were flattened by 600-grit silicone carbide paper disks. Resin blocks were adhered using either Unicem, Maxcem, or Biscem. Light curing timing was divided into two groups: U10, M10, and B10 were exposed to light after 10 seconds, and; U150, M150, and B150 on the other side were exposed to light after 150 seconds. Shear bond strength was measured by a Universal testing machine with cross head speed of 1mm/min. T-test and One way ANOVA were used for the statistical analysis of data. Results. The shear bond strength of U150 was not significantly higher than that of U10 (U150: 20.55.7Mpa, U10: 18.73.80Mpa). On the other hand, the shear bond strength of M150 was significantly higher than that of M10. The shear bond strength of B150 was also significantly higher than that of B10 (M150:14.45.7Mpa, M10: 9.94.2Mpa, B150: 24.38.3Mpa, B10: 17.27.3Mpa). When the light curing timing was 10sec after bonding, the shear bond strength of Unicem was highest; the shear bond strength of Biscem was highest when the light curing timing was 150sec after bonding (U10: 18.73.80Mpa, B150: 24.38.3Mpa). Significance. Since Unicem is less sensitive based on light curing timing, dentists seem to use it without considering the light curing timing. Maxcem showed the lowest bonding strength (especially M10). Thus, when using Maxcem, dentists need to delay the light curing after adhesion.

• Restorative Dentistry and Endodontics
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• v.35 no.6
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• pp.479-485
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• 2010

Objectives: The aim of this study was to compare the push-out bond strengths of resin cement/fiber post systems to post space dentin using different application methods of resin cement. Materials and Methods: Thirty extracted human premolars were selected and randomly divided into 3 groups according to the technique used to place the cement into root canal: using lentulo-spiral instrument (group Lentulo), applying the cement onto the post surface (group Direct), and injecting the material using a specific elongation tip (group Elongation tip). After shaping and filling of the root canal, post space was drilled using Rely-X post drill. Rely-X fiber post was seated using Rely-X Unicem and resin cement was light polymerized. The root specimens were embedded in an acrylic resin and the specimens were sectioned perpendicularly to the long axis using a low-speed saw. Three slices per each root containing cross-sections of coronal, middle and apical part of the bonded fiber posts were obtained by sectioning. The push-out bond strength was measured using Universal Testing Machine. Specimens after bond failure were examined using operating microscope to evaluate the failure modes. Results: Push-out bond strengths were statistically influenced by the root regions. Group using the elongation tip showed significantly higher bond strength than other ways. Most failures occurred at the cement/dentin interface or in a mixed mode. Conclusions: The use of an elongation tip seems to reduce the number of imperfections within the selfadhesive cement interface compared to the techniques such as direct applying with the post and lentulospiral technique.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.613-616
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• 2008

This study is about appling non-exposure waterproofing method which combines the Cement Polymer Modified Waterproof Membrane coating and Selfadhesive Rubberized Asphalt sheet to the Roof Structure, Because there are a lot of problems in previous methods. So We had the performance tests using waterproofing method which combines two materials, and we analyzed the results. This study showed us very important results. We had bond strength test and tensile test under high, normal and low temperature, and the results were successful. And we also tested for coping with crack and movement. We found that tested materials were safe in those conditions. I think that Non-Exposure waterproofing method which combines the Cement Polymer Modified Waterproof Membrane coating and Selfadhesive Rubberized Asphalt sheet is available to concrete structure.