共查询到20条相似文献,搜索用时 15 毫秒
1.
Annika Torbjörner Stig Karlsson Morten Syverud Arne Hensten-Pettersen 《European journal of oral sciences》1996,104(5-6):605-611
The aim of this study was to compare the mechanical properties of a prefabricated root canal post made of carbon fiber reinforced composites (CFRC) with metal posts and to assess the cytotoxic effects elicited. Flexural modulus and ultimate flexural strength was determined by 3 point loading after CRFC posts had been stored either dry or in water. The bending test was carried out with and without preceding thermocycling of the CFRC posts. The cytotoxicity was evaluated by an agar overlay method after dry and wet storage. The values of flexural modulus and ultimate flexural strength were for dry stored CFRC post 82±6 GPa and 1154±65 MPa respectively. The flexural values decreased significantly after water storage and after thermocycling. No cytotoxic effects were observed adjacent to any CFRC post. Although fiber reinforced composites may have the potential to replace metals in many clinical situations, additional research is needed to ensure a satisfying life-span. 相似文献
2.
Gianluca Plotino Nicola M Grande Rossella Bedini Cornelis H Pameijer Francesco Somma 《Dental materials》2007,23(9):1129-1135
OBJECTIVES: To evaluate the flexural modulus and flexural strength of different types of endodontic post in comparison with human root dentin. METHODS: Three different types of fiber-reinforced composite (FRC) posts and three metal posts each comprising 10 specimens (n=10) and 20 dentin bars were loaded to failure in a three-point bending test to determine the flexural modulus (GPa) and the flexural strength (MPa). Three randomly selected fiber posts of each group were evaluated using a scanning electron microscope (SEM) to illustrate the differences in mode of fracture. Data were subjected to a one-way ANOVA to determine significant differences between groups and the Bonferroni t-test multiple comparison was applied to investigate which mean values differed from one another with significance levels of P<0.05. RESULTS: The flexural modulus recorded for the dentin bars was 17.5+/-3.8 GPa. The values for posts ranged from 24.4+/-3.8 GPa for silica fiber posts to 108.6+/-10.7 GPa for stainless steel posts. The flexural strength for dentin was 212.9+/-41.9 MPa, while the posts ranged from 879.1+/-66.2 MPa for silica fiber posts to 1545.3+/-135.9 MPa for cast gold posts. The ANOVA test analysis revealed significant differences between groups (P<0.05) for flexural modulus and flexural strength mean values. SIGNIFICANCE: FRC posts have an elastic modulus that more closely approaches that of dentin while that for metal posts was much higher. The flexural strength of fiber and metal posts was respectively four and seven times higher than root dentin. 相似文献
3.
目的 研究玻璃纤维预拉伸对自行研制的高强玻璃纤维增韧光固化树脂复合材料(FRC)桩力学性能的影响。方法 利用加载装置将高强玻璃纤维分别拉伸0%、0.5%、1.0%后,按60%体积比浸入自行配置的光固化树脂基质,采用压膜法制成玻璃纤维增韧树脂基齿科桩,三点弯曲测试各试样的弯曲模量、弯曲强度和弯曲载荷,测试结果进行统计学分析。使用扫描电子显微镜观察FRC桩横截面和断裂面的形态。结果 玻璃纤维拉伸率对FRC桩的力学性能影响有显著差异,其中拉伸率为1.0%的玻璃纤维制成的FRC桩综合性能最佳,弯曲模量(20.40±1.40) GPa,弯曲强度(573.38±29.45) MPa,弯曲载荷(180.42±5.88) N,与未预拉伸的玻璃纤维增韧的FRC桩有显著差异(P<0.05)。结论 玻璃纤维预拉伸对FRC桩有增韧效果。 相似文献
4.
Kumagae N Komada W Fukui Y Okada D Takahashi H Yoshida K Miura H 《Dental materials journal》2012,31(1):113-119
The purpose of this study was to evaluate the influence of flexural modulus of non-metal posts on the fracture strength and failure mode of composite resin cores. Thirty-two human premolars were divided into four groups: prefabricated glass fiber post with 1.0 mm diameter and composite resin core (Group PE1.0), that with 1.5 mm diameter and composite resin core (Group PE1.5), experimental post (flexural modulus; 4.25GPa) and composite resin core (Group EX), and preparation for abutment teeth only (Group NT). After a static loading test, the fracture strength and failure mode were recorded. Group NT (1670.81 N) showed higher fracture strength than Groups PE1.0 (866.44 N), PE1.5 (825.19 N) and EX (1075.63 N) (p<0.05). This study showed that the fracture strength of endodontically treated teeth restored with composite resin cores is not influenced by the flexural modulus of non-metal posts. 相似文献
5.
Objectives
It is suggested that fibre-reinforced composite (FRC) posts have lower elastic moduli than metal posts and this will reduce the incidence of root fracture. However, the mechanical properties may be altered in the oral environment. The aims of this study were to determine the effect on the flexural properties of FRC and metal post materials produced by: (1) a thermocycling regime which was clinically relevant and representative of that which would occur during 1 year in the mouth and (2) storage for 1 year at body temperature.Methods
Nine FRC and two metal post material samples were sealed in polythene sleeves and thermocycled between 10 °C and 50 °C for 10,000 cycles. Additional samples were stored dry at 37 °C for 1 year. The flexural strength and moduli were determined by three-point bending and compared with untreated control samples.Results
Thermocycling and storage at 37 °C for 1 year decreased the mean flexural modulus of all materials. This was statistically significant for 8 of 11 materials after thermocycling, and 4 of 11 materials after storage at 37 °C (p < 0.05). Thermocycling and storage at 37 °C produced a non-significant increase in yield strength for both metal post materials. Thermocycling significantly increased the flexural strength of Postec while it decreased for the other FRC materials. Storage at 37 °C increased the flexural strength of three FRC materials (significantly for Postec) while it was decreased among the other materials.Conclusions
Although some of the changes noticed in flexural properties were statistically significant, it is doubtful that they are of sufficient magnitude to affect clinical performance. 相似文献6.
OBJECTIVES: The aim of this study was to examine the emission of acoustic signals from six commercially available fiber-reinforced composites (FRC) used in the frameworks of fixed partial dentures in material bending. METHODS: FRC test specimens were made of six commercially available fiber products of polyethylene or glass and five light-curing resins. FRC test specimens were polymerized with a hand light-curing unit or with a light-curing oven. The flexural test for determination of ultimate flexural strength of test specimens (n = 6) was based on the ISO 10477 standard after the specimens were stored in air or in water for two weeks. The acoustic emission (AE) signals were monitored during three-point loading test of the test specimens using a test with increasing loading levels until the specimens fractured. RESULTS: Generally, stress level required for the AE activity initiation ranged from 107 MPa (Ribbond) to 579 MPa (everStick). The ultimate flexural strength of FRC specimens were higher, ranging from 132 to 764 MPa, being highest with everStick and Vectris FRC, and lowest with Ribbond FRC. ANOVA showed a statistically significant difference between the initiation of AE activity and the ultimate flexural strength according to the brand (p < 0.001) storing conditions (p < 0.001) and polymerization procedure (p < 0.001). AE activity and ultimate flexural strength correlated significantly (p < 0.010, r = 0.887). SIGNIFICANCE: The result of this study suggested that AE activity in FRC specimens started at a 19-32% lower stress level than occurred at final fracture. 相似文献
7.
Lassila LV Tezvergil A Lahdenperä M Alander P Shinya A Shinya A Vallittu PK 《Acta odontologica Scandinavica》2005,63(4):196-204
OBJECTIVE: Water sorption, flexural properties, bonding properties, and elemental composition of photopolymerizable resin-impregnated fiber-reinforced composite (FRC) materials (everStick C&B and BR-100) (FPD) were evaluated in this study. MATERIAL AND METHODS: Bar-shaped specimens (2 x 2 x 25 mm) were prepared for water sorption and flexural strength testing. The specimens (n = 6) were polymerized either with a hand light-curing unit for 40 s or, additionally, in a light-curing oven for 20 min and stored in water for 30 days. Water sorption was measured during this time, followed by measurements of flexural strength and modulus. A shear bond strength test was performed to determine the bonding characteristics of polymerized FRC to composite resin luting cement (Panavia-F), (n = 15). The cement was bonded to the FRC substrate and the specimens were thermocycled 5000 times (5-55 degrees C) in water. SEM/EDS were analyzed to evaluate the elemental composition of the glass fibers and the fiber distribution in cross section. RESULTS: ANOVA showed significant differences in water sorption according to brand (p < 0.05). Water sorption of everStick C&B was 1.86 wt% (hand-unit polymerized) and 1.94 wt% (oven polymerized), whereas BR-100 was 1.07 wt% and 1.17 wt%, respectively. The flexural strength of everStick C&B after 30 days' water storage was 559 MPa (hand-unit polymerized) and 796 MPa (oven-polymerized); for BR-100, the values were 547 MPa and 689 MPa, respectively. Mean shear bond strength of composite resin cement to the FRC varied between 20.1 and 23.7 MPa, showing no statistical difference between the materials. SEM/EDS analysis revealed that fibers of both FRC materials consist of the same oxides (SiO2, CaO, and Al2O3) in ratios. The distribution of fibers in the cross section of specimens was more evenly distributed in everStick C&B than in BR-100. CONCLUSION: The results of this study suggest that there are some differences in the tested properties of the FRC materials. 相似文献
8.
Pereira JR de Oliveira JA do Valle AL Zogheib LV Ferreira PM Bastos LG 《General dentistry》2011,59(4):e144-e148
The aim of this study was to evaluate the effect of prefabricated fiber posts on the flexural strength and modulus of elasticity of a composite resin. Thirty bar-shaped specimens measuring 25 x 2.0 x 2.0 mm were made, containing posts that were 1.3 mm in diameter and 20 mm long. Each group contained 10 specimens: Group 1, resin without post; Group 2, resin with carbon fiber post; Group 3, resin with glass fiber post. The samples were immersed in water at 37 degrees C until the three-point loading test was performed at a speed of 1.0 mm/minute. The results were statistically analyzed by ANOVA and Tukey's test (P = 0.05). Both fiber posts were similar in strength and both were stronger than the control. Group 3 obtained a higher mean modulus of elasticity than Groups 1 and 2, which were similar. The results of this study demonstrated that the presence of a fiber post significantly raised flexural strength values and the glass fiber post significantly increased the modulus of elasticity of the evaluated composite resin. 相似文献
9.
AIM: The aim of this study was to determine the effect of short fiber volume fraction and fiber length on some mechanical properties of short fiber-reinforced composite (FRC). METHODS AND MATERIALS: Test specimens (2 x 2 x 25 mm3) and (9.5 x 5.5 x 3 mm3) were made from short random FRC and prepared with different fiber volumes (0%-22%) and fiber lengths (1-6 mm). Control specimens did not contain fiber reinforcement. The test specimens (n=6) were either dry stored or thermocycled in water (x10.000, 5-55 degrees C) before loading (three-point bending test) according to ISO 10477 or statically loaded with a steel ball (? 3.0 mm) with a speed of 1.0 mm/min until fracture. A universal testing machine was used to determine the flexural properties and the load-bearing capacity. Data were analyzed using analysis of variance (ANOVA) (p=0.05) and a linear regression model. RESULTS: The highest flexural strength and fracture load values were registered for specimens with 22 vol% of fibers (330 MPa and 2308 N) and with 5 mm fiber length (281 MPa and 2222 N) in dry conditions. Mechanical properties of all test specimens decreased after thermocycling. ANOVA analysis revealed all factors were affected significantly on the mechanical properties (p<0.001). CONCLUSIONS: By increasing the volume fraction and length of short fibers up to 5 mm, which was the optimum length, the mechanical properties of short FRC were improved. 相似文献
10.
Carola Kolbeck Martin Rosentritt Michael Behr Stefan Schneider Gerhard Handel 《Dental materials》2007,23(12):1529-1534
OBJECTIVES: The aim of this in vitro study was to determine the effect of electron irradiation on the fracture strength, elongation and bond capacities on different fiber reinforced composites (FRC). METHODS: Thirty-two bending bars (25mmx2mmx2mm) were fabricated per material (Construct: Kerr, Rastatt, Germany; everStick: StickTech, Turku, Finland; FibreKor: JenericPentron, Wallingford/CT, USA), divided into four irradiation groups (0kGy, 15kGy, 33kGy and 100kGy) and fracture loaded after irradiation. Forty-eight plates (20mmx10mmx2mm) of the FRC materials were made and divided into different pretreatment (Clearfil SE Bond Bond: Kuraray Europe, Düsseldorf, Germany; SRLink: Ivoclar-Vivadent, Schaan, Liechtenstein; MetalPrimerII: GC, Tokio, Japan; Rocatec: 3M Espe, Seefeld, Germany) and irradiation (0kGy, 15kGy and 33kGy) groups. After irradiation of the pretreated plates the veneering composite Sinfony (3M Espe, Seefeld, Germany) was applied (area ?=5mm), water stored for 120 days and then the shear bond strength (SBS) was evaluated. Medians and 25%/75%-percentiles were calculated, statistical analysis was performed (Mann-Whitney U-test: p=0.05). RESULTS: Fracture strength increased significantly for all materials when irradiated, elongation decreased for everStick and Construct and increased for FibreKor. The non-irradiated various pretreatments did not influence SBS. Irradiation led to significant changes for FibreKor pretreated with SR-Link, MetalPrimerII and Clearfil SE Bond Bond. SIGNIFICANCE: Electron irradiation can probably increase the fracture resistance of FRC fixed partial dentures if the right combinations of FRC material, pretreatment and electron irradiation doses are chosen. The FRC materials could be industrially advanced if irradiation was integrated into material development. 相似文献
11.
Arzu Tezvergil Lippo Lassila Antti Yli‐Urpo Pekka Vallittu 《Acta odontologica Scandinavica》2013,71(1):51-60
Delamination or fracture of composite veneers can occur as a result of improper design of the fiber‐reinforced composite (FRC) framework. This in vitro study tested the repair bond strength of restorative composite to aged FRC. The substrate was multiphase polymer matrix FRC (everStick) aged by boiling for 8 h and storing at 37°C in water for 6 weeks. The aged substrate surfaces were wet‐ground flat with 1200‐grit silicon carbide paper and subjected randomly to 5 different surface treatments: 1) An adhesion primer (Composite Activator) and resin (CA), 2) Silane (EspeSil) and resin (SIL‐MP), 3) Silane, adhesive primer, and resin (Clearfil Repair) (CF), 4) Air particle‐abrading (CoJet), silane, and resin (CJ‐SIL‐MP), 5) Resin (Scotchbond Multipurpose Resin) only as control (MP). Restorative composite resin (Z250) was added to the substrate in 2 mm layer increments and light‐cured. Subsequently, every surface treatment group was divided into 2 subgroups of 12 specimens each. The specimens were either 48 h water‐stored or thermocycled (6000 x 5–55°C). The shear bond strengths of composite resin to FRC were measured at a crosshead speed of 1.0 mm/min. The data were analyzed by ANOVA for factors ‘treatment type’ and ‘storage condition’; Tukey's post‐hoc tests and Weibull analysis were performed. ANOVA showed a significant difference as a function of surface treatment (P<0.05) and storage condition (P<0.05). The CJ‐SIL‐MP group showed highest bond strength and Weibull modulus after thermocycling. Repair of multiphase polymer matrix FRC may show reliable bond strength when silane treatment is used along with air‐particle abrading. 相似文献
12.
Resistance to fracture and structural characteristics of different fiber reinforced post systems. 总被引:5,自引:0,他引:5
OBJECTIVES: The aim of this study was to investigate the ultrastructure and resistance to fracture of eight different types of fiber post, and to verify the existence of a correlation between structural characteristics and flexural strength. METHODS: Eight types of fiber post were selected for this study. Fiber Kor (Jeneric-Pentron), Para Post Fiber White (Colténe), Luscent Anchor (Dentatus), Twin-Luscent Anchor (Dentatus), Style Post (Metalor), DT White-Post (VDW), DT Light-Post (VDW) and ER Dentin Post (Brasseler). Ten posts of each experimental group were selected for a three-point bending test, and one was processed for SEM evaluation. A universal testing machine loading at an angle of 90 degrees was employed for the three-point bending test. The test was carried out until fracturing of the post. After fracture testing, the posts with the highest and the lowest values of flexural strength of each system were additionally processed for SEM analysis. SEM evaluation was performed using a PC-measurement program to assess the fiber/matrix ratio and fiber dimensions. RESULTS: The fracture load of the tested systems ranged from 60 to 96 N and the flexural strength from 565 to 898 MPa. DT White-Post and DT Light-Post (898 and 842 MPa, respectively) had significantly higher flexural strengths than the other posts. Style Post (565 MPa) showed a significantly lower flexural strength than all other posts. The differences in fiber diameter ranged from 8.2 to 21 microm and for the fiber/matrix ratio from 41 to 76%. Of the various structural characteristics investigated, only the fiber/matrix ratio showed a significant correlation to the flexural strength (r=0.922, p=0.003). SIGNIFICANCE: The FRC-posts investigated displayed significant differences with regard to fracture load and flexural strength. A strong and significant linear correlation between the fiber/matrix ratio and the flexural strength was found. 相似文献
13.
OBJECTIVES: The aim of this study was to determine experimentally flexural strength and flexural modulus of fiber-reinforced composite (FRC) with different cross-sectional designs and diameters and tested with different span lengths. METHODS: Continuous FRC test specimens (n = 6) were made with two different cross-sectional designs, namely circular and rectangular. The resin matrix of FRC was polymerized with a hand light-curing unit followed by a light-curing oven polymerization. Three-point flexural test for determination of ultimate flexural strength and flexural modulus of the dry test specimens was made with different span lengths for rectangular specimens and diameters for circular specimens. Thus, the span length/diameter ratio (L/D) was changed. RESULTS: Flexural strength and flexural modulus of specimens with rectangular cross-section varied from 540 to 792 MPa and 9.8 to 20.3 GPa being the highest with the group of the 20 mm span length and the lowest with the group of the 10 mm span length. Flexural strength and flexural modulus of circular cross-section specimens varied from 847 to 1286 MPa and 19.9 to 36.6 GPa being the highest with 1.5 mm cross-section and the lowest with 2.8 mm cross-section. SIGNIFICANCE: It was concluded, that by increasing the L/D ratio, the flexural strength and flexural modulus values in MPa increased and the maximum fracture load values in N decreased. Reporting the L/D ratio is essential for interpretation of flexural strength and flexural modulus values of small size test specimens. 相似文献
14.
不同弯曲度对牙科纤维增强复合材料桩钉性能的影响 总被引:2,自引:0,他引:2
目的研制一套具有不同弯曲角度的牙科纤维增强复合材料(FRC)桩钉,探讨弯曲角度对FRC桩钉性能的影响。方法自行设计一套金属模具,利用该模具制作一套弯曲角度分别为5°、10°、15°的FRC弯钉。三点挠曲实验比较不同弯曲度的FRC弯钉与FRC直钉的挠曲强度和挠曲模量。结果15°FRC弯钉的挠曲性能低于5°、10°及直钉,差异均有统计学意义(P<0.05),其余各组FRC桩钉的挠曲性能,差异无统计学意义(P>0.05)。结论自制FRC桩钉的弯曲角度在0°、5°、10°时,其对材料力学性能影响较小。 相似文献
15.
OBJECTIVE: The aim of this study was to determine bonding properties of two types of fibre-reinforced composite (FRC) posts cemented into root canals of molars. Serrated titanium posts served as reference. METHODS: Prefabricated carbon/graphite FRC posts with cross-linked polymer matrix and individually formed glass FRC posts with interpenetrating polymer network (IPN) polymer matrix were compared. The crowns of extracted third molars were removed and post space (diameter: 1.5mm) was drilled, etched and bonded. The posts were treated with dimethacrylate adhesive resin, light-polymerized and cemented with a dual-polymerizing composite resin luting cement. After thermocycling (6000x) the samples were cut into discs of thicknesses: 1, 2 and 4mm (n=12/group). Push-out force was measured by pushing the post from one end. Assessment of failure mode was made under a stereomicroscope (1, adhesive failure between post and cement; 2, cohesive failure of post-system; 3, adhesive failure between cement and dentin). RESULTS: The push-out force increased with increased height of dentin disc in all groups (ANOVA, p<0.001). In the 4mm thick dentin discs the individually formed glass FRC posts showed highest push-out force and the difference to that of the titanium posts was significant (ANOVA, p<0.001). The other differences were not statistically significant. None of the individually formed glass FRC posts showed adhesive failures between the post and the cement. CONCLUSIONS: Contrary to the other posts, there were no adhesive (post-cement) failures with the individually formed glass FRC posts, suggesting better interfacial adhesion of cement to these posts. 相似文献
16.
Manila Chieruzzi Stefano Pagano Manuela Pennacchi Guido Lombardo Potito D’Errico Josè M. Kenny 《Journal of dentistry》2012,40(11):968-978
ObjectivesThe aim of this study was to investigate the mechanical properties of five types of fibre-reinforced composite (FRC) posts and compare them with traditional metal post.MethodsFive FRC posts and a metallic post having different geometry and type of fibre (glass, carbon or quartz fibre) were loaded to failure in compression and bending. The transverse sections of FRC posts were observed using SEM to evaluate the fracture mode and the percentage of fibres (compared with burn-off test). Densities and voids content were also evaluated.ResultsMechanical results were subjected to a one-way ANOVA and Tukey test (p < 0.05). In compression, quartz fibre posts exhibited the greater maximum load and ultimate strength, carbon fibre posts showed a poor compressive behaviour. All posts had similar compressive moduli.Carbon posts showed the highest flexural properties (p < 0.0001) while glass posts the greater maximum load. The fracture load values correlated to the diameters of posts showed a parabolic behaviour. The flexural strengths of all posts were four and seven times higher than dentine.The elastic moduli of almost all posts were similar to dentine. The compressive strengths were lower than flexural strengths. The fibre diameters ranged from 5.2 to 26 μm, the volume percentage of fibres was about 64%. The content of voids of some posts lower their mechanical behaviour.ConclusionsCompressive properties of FRC posts were lower than in bending. The flexural properties of FRC posts were higher than the metal post and similar to dentine. The mechanical behaviour is influenced by voids. 相似文献
17.
Flexural and fatigue strengths of root canal posts 总被引:1,自引:0,他引:1
This study measured the flexural and fatigue strengths of root canal posts of different alloy, design, and diameter. Fixed posts were loaded up to a preset force and the number of loadings endured until fracture was recorded at each loading force. The flexural strength was defined as the maximum force a post could endure before fracture when loaded once. The fatigue strength was determined as the maximum force a post could endure when loaded 10,000 times. Both modes of strength were found to increase with increasing diameter. Aluminum posts had lower flexural and fatigue strengths than posts of titanium, stainless steel, and a Ag-Pd alloy, all of which had strength values of about the same magnitude. Among the investigated brands, Triax and Radix were stronger than the others at comparable diameters. The high strength of Triax may be explained by the design of the post, whereas a superior alloy may account for the high strength of Radix. 相似文献
18.
目的 研究不同表面预处理的高强玻璃纤维对纤维增强光固化树脂复合材料(FRC)桩的力学性能的影响。方法 将玻璃纤维分为4组分别进行以下表面处理:不预处理、450 ℃高温处理、450 ℃高温+10%HCl蚀刻1 h、450 ℃高温+10% HCl蚀刻3 h,然后将4组纤维经过硅烷偶联剂处理后按相同体积比浸入自行配制的光固化树脂基质中,用压挤法制成纤维增强树脂基桩。测试试样的弯曲模量、弯曲强度、弯曲载荷,扫描电子显微镜观察FRC截面和断裂面的形态。结果 不同表面预处理后的玻璃纤维对FRC桩的力学性能有显著差异,其中450℃+KH570组制成的FRC桩性能最佳,弯曲模量、弯曲强度、弯曲载荷分别为(37.70±1.46) GPa、(737.00±25.51) MPa、(196.53±6.80) N,与其余组有显著差异(P<0.05)。结论 450 ℃高温+KH570处理玻璃纤维对FRC桩的增韧效果最佳。 相似文献
19.
Abstract – This study measured the flexural and fatigue strengths of root canal posts of different alloy, design, and diameter. Fixed posts were loaded up to a preset force and the number of loadings endured until fracture was recorded at each loading force. The flexural strength was defined as the maximum force a post could endure before fracture when loaded once. The fatigue strength was determined as the maximum force a post could endure when loaded 10000 times. Both modes of strength were found to increase with increasing diameter. Aluminum posts had lower flexural and fatigue strengths than posts of titanium, stainless steel, and a Ag-Pd alloy, all of which had strength values of about the same magnitude. Among the investigated brands, Triax and Radix were stronger than the others at comparable diameters. The high strength of Triax may be explained by the design of the post, whereas a superior alloy may account for the high strength of Radix. 相似文献
20.
Lippo VJ Lassila Arzu Tezvergil Milla Lahdenperä Pasi Alander Akiyoshi Shinya Akikazu Shinya 《Acta odontologica Scandinavica》2013,71(4):196-204
Objective. Water sorption, flexural properties, bonding properties, and elemental composition of photopolymerizable resin-impregnated fiber-reinforced composite (FRC) materials (everStick C&B and BR-100) (FPD) were evaluated in this study. Material and methods. Bar-shaped specimens (2×2×25 mm) were prepared for water sorption and flexural strength testing. The specimens (n=6) were polymerized either with a hand light-curing unit for 40 s or, additionally, in a light-curing oven for 20 min and stored in water for 30 days. Water sorption was measured during this time, followed by measurements of flexural strength and modulus. A shear bond strength test was performed to determine the bonding characteristics of polymerized FRC to composite resin luting cement (Panavia-F), (n=15). The cement was bonded to the FRC substrate and the specimens were thermocycled 5000 times (5–55°C) in water. SEM/EDS were analyzed to evaluate the elemental composition of the glass fibers and the fiber distribution in cross section. Results. ANOVA showed significant differences in water sorption according to brand (p<0.05). Water sorption of everStick C&B was 1.86 wt% (hand-unit polymerized) and 1.94 wt% (oven polymerized), whereas BR-100 was 1.07 wt% and 1.17 wt%, respectively. The flexural strength of everStick C&B after 30 days’ water storage was 559 MPa (hand-unit polymerized) and 796 MPa (oven-polymerized); for BR-100, the values were 547 MPa and 689 MPa, respectively. Mean shear bond strength of composite resin cement to the FRC varied between 20.1 and 23.7 MPa, showing no statistical difference between the materials. SEM/EDS analysis revealed that fibers of both FRC materials consist of the same oxides (SiO2, CaO, and Al2O3) in ratios. The distribution of fibers in the cross section of specimens was more evenly distributed in everStick C&B than in BR-100. Conclusion. The results of this study suggest that there are some differences in the tested properties of the FRC materials. 相似文献