Fiber-reinforced Composite Posts Research Articles

Effect of Er:YAG laser pretreatment on bond strength of a composite core build-up material to fiber posts

The study evaluated the micro push-out bond strength of resin material (Multicore Flow) to two types of fiber posts (FP), namely fiber-reinforced composite (FRC) Postec and Radix Fiber posts using Er:YAG laser pretreatment. FP were divided into four groups, two being control groups. Before the core build-up procedure, representative specimens from each group were chosen to determine the surface roughness (Ra) at three different areas using a contact profilometer, while after the procedure, 1.5-mm-thick discs were sectioned and the micro push-out method was used to assess the bond strength of the core build-up material to the fiber post in each group. Two-way analysis of variance was used for statistical analysis with the level of significance set at p < 0.05. Scanning electron microscopy was used to analyze the post surfaces after Er:YAG laser pretreatment and to classify the failure mode after loading. The type of pretreatment (p < 0.001) and an interaction between the pretreatment and type of post (p < 0.001) had a significant effect on the bond strength, while the type of post did not (p = 0.965). The mean bond strength in the Er:YAG laser pretreatment group was significantly lower compared to the FRC Postec posts control group (p < 0.001), while there was no significant difference between the Radix Fiber posts groups (p = 0.680). Mean Ra values from the Er:YAG laser pretreatment groups were significantly higher compared to control groups (p < 0.001). Er:YAG laser pretreatment at tested parameters negatively affected the bond strength of Multicore to FP and cannot be recommended as a standard procedure.

Comparison of the Bond Strength of Fiber-Reinforced Composite (FRC) Posts to Radicular Dentin Using Different Adhesive Cement: an in-vitro study

Comparison of the Bond Strength of Fiber-Reinforced Composite (FRC) Posts to Radicular Dentin Using Different Adhesive Cement: an in-vitro study

Effect of Cementation Technique of Individually Formed Fiber-Reinforced Composite Post on Bond Strength and Microleakage

The aim of this study was to evaluate the effect of two different cementation techniques of individually formed E-glass fiber-reinforced composite (FRC) post on bond strength and microleakage. The crowns of extracted third molars were removed and post preparation was carried out with parapost drills (diameter 1.5 mm). After application of bonding agents individually formed FRC posts (everStick POST, diameter 1.5 mm) were cemented into the post spaces with either ParaCem®Universal or self-adhesive RelyX™Unicem, using two different cementation techniques: 1) an "indirect (traditional) technique" where the post was prepolymerized prior application of luting cement and insertion into the post space or 2) a "direct technique" where the uncured post was inserted to the post space with luting cement and light-polymerized in situ at the same time. After water storage of 48 hours, the roots (n = 10/group) were cut into discs of thickness of 2 mm. A push-out force was applied until specimen fracture or loosening of the post. A microleakage test was carried out on roots which were not subjected to the loading test (n= 32) to evaluate the sealing capacity of the post-canal interface. The microleakage was measured using dye penetration depth under a stereomicroscope. Higher bond strength values (p<0.05) and less microleakage (p<0.05) were obtained with the "direct technique" compared to the "indirect technique". None of the FRC posts revealed any dye penetration between the post and the cement. The "direct technique" seems to be beneficial when cementing individually formed FRC posts.

The literature-based comparison between the properties of posterior teeth restored with prefabricated glass fibre-reinforced composite posts and endocrowns

The literature-based comparison between the properties of posterior teeth restored with prefabricated glass fibre-reinforced composite posts and endocrowns

Effect of components and surface treatments of fiber-reinforced composite posts on bond strength to composite resin

The aim of this study was to clarify the effect of the components and surface treatments of fiber-reinforced composite (FRC) posts on the durable bonding to core build-up resin evaluated using the pull-out and microtensile tests. Four types of experimental FRC posts, combinations of two types of matrix resins (polymethyl methacrylate and urethane dimethacrylate) and two types of fiberglass (E-glass and zirconia-containing glass) were examined. The FRC posts were subjected to one of three surface treatments (cleaned with ethanol, dichloromethane, or sandblasting). The bond strength between the FRC posts and core build-up resin were measured using the pull-out and microtensile tests before and after thermal cycling. The bond strengths obtained by each test before and after thermal cycling were statistically analyzed by three-way ANOVA and Tukey's multiple comparisons test (p<0.05). The bond strengths except for UDMA by the pull-out test decreased after thermal cycling. Regardless the test method and thermal cycling, matrix resins, the surface treatment and their interaction were statistically significant, but fiberglass did not. Dichloromethane treatment was effective for the PMMA-based FRC posts by the pull-out test, but not by the microtensile test. Sandblasting was effective for both PMMA- and UDMA-based FRC posts, regardless of the test method. The bond strengths were influenced by the matrix resin of the FRC post and the surface treatment. The bond strengths of the pull-out test showed a similar tendency of those of the microtensile test, but the value obtained by these test were different.

Influence of Post Fit and Post Length on Fracture Resistance: An in vitro Study

As root filled teeth often have insufficient coronal tooth structure, placement of a post is occasionally necessary to provide adequate retention for the core and final restoration. The aim of the present study was to investigate (i) the impact of post fit (form-congruence) and (ii) the influence of post length on the fracture resistance of severely damaged root filled extracted teeth. Forty single-rooted human teeth were root filled and divided into four groups (n = 10 per group). Post spaces were prepared with a depth of 6 mm (groups 1, 3) and 3 mm (groups 2, 4). Form-congruence with a maximal fit of the post within the root canal space was obtained in groups 1 and 2, whereas there was no form-congruence in groups 3 and 4. In all groups, glass fiber reinforced composite (FRC) posts were adhesively cemented and direct composite crown buildups were fabricated without a ferrule. Specimens were subjected to thermocycling and cyclic loading followed by application of static load until failure. Loads-to-failure [in N] were compared among the groups. Post fit did not have a significant influence on fracture resistance, irrespective of the post length. Both groups with post insertion depths of 6 mm resulted in significantly higher mean failure loads (group 1: 274.27 N; group 3: 277.16 N) than the groups with post space preparation of 3 mm (group 2: 250.40 N; group 4: 255.48 N). Within the limitations of this study, the fracture resistance of teeth restored with FRC posts and direct resin composite crowns without ferrules was not influenced by post fit within the root canal. These results imply that excessive post space preparation aimed at producing an optimal circumferential post fit is not required to improve fracture resistance of roots.

Pasak estetik dari bahan fiber reinforced composite Esthetic post made of fiber reinforced composite materials

The prosthetic treatment of seriously damaged teeth after treated with endodontic often require an endodontic post asan additional retention element for core build-up prior to crown restoration. In addition to metal-based posts andzirconia-based ceramic posts, fiber reinforced composite (FRC) post system has become to be widely used in therestoration of endodontically treated teeth. A FRC post offers a number of advantages over a metal post due to itsmodulus of elasticity being closer to that of dentin and superior esthetic quality. Teeth restored with FRC posts showbetter resistance to fracture propagation than teeth restored with prefabricated or cast metal posts. Endodonticallytreated teeth reinforced with a prefabricated fiber post have shown lower incidences of root fracture.

Effect of adhesive system on retention in posts comprising fiber post and core resin

The purpose of this study was to compare the retention of fiber-reinforced composite (FRC) posts luted with either conventional or self-adhesive resin cement. The FRC posts and core resin were built up in bovine teeth. The posts were luted with standard etch-andrinse cement, self-etch cement, or one of two self-adhesive cements. The samples were stored in water for 1 or 14 days or subjected to thermal cycling (TC). Retention value was measured with the pull-out test using a universal testing machine. Conventional adhesive resin cement yielded significantly greater retention than self-adhesive resin cement at 1 day. No significant difference was observed in retention among the adhesive systems tested at 14 days or after TC. During the early luting stage, self-adhesive resin cement yielded lower retention value than conventional resin cement. After 14 days storage or TC, retention was comparable to that with conventional resin cement.

Effect of silane activation on shear bond strength of fiber-reinforced composite post to resin cement

PURPOSEAmong the surface treatment methods suggested to enhance the adhesion of resin cement to fiber-reinforced composite posts, conflicting results have been obtained with silanization. In this study, the effects of silanization, heat activation after silanization, on the bond strength between fiber-reinforced composite post and resin cement were determined.MATERIALS AND METHODSSix groups (n=7) were established to evaluate two types of fiber post (FRC Postec Plus, D.T. Light Post) and three surface treatments (no treatment; air drying; drying at 38℃). Every specimen were bonded with dual-curing resin cement (Variolink N) and stored in distilled water for 24 hours at 37℃. Shear-bond strength (MPa) between the fiber post and the resin cement were measured using universal testing device. The data were analyzed with 1-way ANOVA and by multiple comparisons according to Tukey's HSD (α=0.05). The effect of surface treatment, fiber post type, and the interactions between these two factors were analyzed using 2-way ANOVA and independent sample T-tests.RESULTSSilanization of the FRC Postec Plus significantly increased bond strength compared with the respective non-treated control, whereas no effect was determined for the D.T. Light Post. Heat drying the silane coupling agent on to the fiber-reinforced post did not significantly improve bond strength compared to air-syringe drying.CONCLUSIONThe bond strength between the fiber-reinforced post and the resin cement was significantly increased with silanization in regards to the FRC Postec Plus post. Bond strength was not significantly improved by heat activation of the silane coupling agent.

Effect of eugenol-containing sealer and post diameter on the retention of fiber reinforced composite posts

Background:Fiber reinforced composite (FRC) posts are cemented with resin cements. It is reported that using resin cements in canals sealed with eugenol-containing sealers reduces the post retention. However, there is controversy on the subject.Aims:The aim was to investigate the influence of eugenol-containing sealers and the amount of dentin removal from root canal with different post diameters on retention of FRC posts.Settings and Design:It was an in vitro studyMaterials and Methods:The roots of sixty teeth were cut with 14 mm distance from the apex and were instrumented to the working-length of 13 mm. The teeth were randomly distributed into 2 groups (n = 30). Following storage in normal saline for 7 days, the samples in both the groups were further divided into 3 subgroups (n = 10). Canals in the experimental subgroups (I, II, III) were obturated by gutta-percha and eugenol-containing sealer; and in the control subgroups (IV, V, VI) without any sealer. After storage in normal saline for 7 days, the post space was prepared by #3, #2, and #1 drills of DT Light-Post system. Post was cemented with Panavia-F2.0 resin-cement. A composite core was built for each sample. All samples were thermo cycled for 1000 cycles. The samples were tested for post retention with a mechanical testing machine.Statistical Analysis:Data were analyzed by two-way ANOVA and Tukey-HSD test.Results:There was not a significant difference in retention between FRC posts #1 and #2 (P > 0.05). Post #3 was more retentive than posts #1and #2 (P < 0.05). ZOE sealer significantly reduced the retention of posts (P = 0.024), however, increasing post-space diameter significantly increased post retention in canals coated with ZOE sealer (P = 0.002).Conclusions:Eugenol-containing sealer reduced the retention of FRC posts cemented with resin cement. Removing more dentin from root-canals treated with eugenol-containing sealer for placing larger diameter posts caused an increase in post retention.

Push-out bond strengths of fiber-reinforced composite posts with various resin cements according to the root level

PURPOSEThe aim of this study was to determine whether the push-out bond strengths between the radicular dentin and fiber reinforced-composite (FRC) posts with various resin cements decreased or not, according to the coronal, middle or apical level of the root.MATERIALS AND METHODSFRC posts were cemented with one of five resin cement groups (RelyX Unicem: Uni, Contax with activator & LuxaCore-Dual: LuA, Contax & LuxaCore-Dual: Lu, Panavia F 2.0: PA, Super-Bond C&B: SB) into extracted human mandibular premolars. The roots were sliced into discs at the coronal, middle and apical levels. Push-out bond strength tests were performed with a universal testing machine at a crosshead speed of 0.5 mm/min, and the failure aspect was analyzed.RESULTS There were no significant differences (P>.05) in the bond strengths of the different resin cements at the coronal level, but there were significant differences in the bond strengths at the middle and apical levels (P<.05). Only the Uni and LuA cements did not show any significant decrease in their bond strengths at all the root levels (P>.05); all other groups had a significant decrease in bond strength at the middle or apical level (P<.05). The failure aspect was dominantly cohesive at the coronal level of all resin cements (P<.05), whereas it was dominantly adhesive at the apical level.CONCLUSIONAll resin cement groups showed decreases in bond strengths at the middle or apical level except LuA and Uni.

Influence of proximal contacts and FRC posts on the fracture behavior of premolars with class II composite restorations: An in-vitro study

The purpose of this study was to evaluate the influence of the number of proximal contacts and fiber-reinforced composite (FRC) post insertion on the fracture behavior of endodontically treated premolars with class II (MOD) cavities and direct composite restorations. Forty-eight single-rooted human premolars were endodontically treated and prepared with standardized MOD (mesio-occluso-distal) cavities. One-half of the teeth additionally received FRC-posts (DT Light SL) luted with Panavia F resin cement. All of the specimens were restored with direct composite restorations, and the teeth were embedded in proximal contact with either zero, one or two adjacent tooth-replicas. Eight sound premolars served as control. After thermomechanical ageing, the samples were loaded until fracture at an angle of 30°. The sound teeth showed the highest mean fracture load. Teeth with one or two proximal contacts and FRC-posts showed only statistically insignificantly lower values. All of the other groups had significantly lower values.

Effect of Cementation Technique of Individually Formed Fiber-Reinforced Composite Post on Bond Strength and Microleakage

Objectives: The aim of this study was to evaluate the effect of two different cementation techniques of individually formed E-glass fiber-reinforced composite (FRC) post on bond strength and microleakage. Methods: The crowns of extracted third molars were removed and post preparation was carried out with parapost drills (diameter 1.5 mm). After application of bonding agents individually formed FRC posts (everStick POST, diameter 1.5 mm) were cemented into the post spaces with either ParaCem®Universal or self-adhesive RelyX™Unicem, using two different cementation techniques: 1) an “indirect (traditional) technique” where the post was prepolymerized prior application of luting cement and insertion into the post space or 2) a “direct technique” where the uncured post was inserted to the post space with luting cement and light-polymerized in situ at the same time. After water storage of 48 hours, the roots (n = 10/group) were cut into discs of thickness of 2 mm. A push-out force was applied until specimen fracture or loosening of the post. A microleakage test was carried out on roots which were not subjected to the loading test (n= 32) to evaluate the sealing capacity of the post-canal interface. The microleakage was measured using dye penetration depth under a stereomicroscope. Results: Higher bond strength values (p<0.05) and less microleakage (p<0.05) were obtained with the “direct technique” compared to the “indirect technique”. None of the FRC posts revealed any dye penetration between the post and the cement. Conclusions: The “direct technique” seems to be beneficial when cementing individually formed FRC posts.

Evaluation of push-out bond strength of two fiber-reinforced composite posts systems using two luting cements in vitro

Introduction:The concept of using a “post” for the restoration of teeth has been practiced to restore the endodontically treated tooth. Metallic posts have been commonly used, but their delirious effects have led to the development of fiber-reinforced materials that have overcome the limitations of metallic posts. The use of glass and quartz fibers was proposed as an alternative to the dark color of carbon fiber posts as far as esthetics was concerned. “Debonding” is the most common failure in fiber-reinforced composite type of posts. This study was aimed to compare the push-out bond strength of a self-adhesive dual-cured luting agent (RelyX U100) with a total etch resin luting agent (Variolink II) used to cement two different FRC posts.Materials and Methods:Eighty human maxillary anterior single-rooted teeth were decoronated, endodontically treated, post space prepared and divided into four groups (n = 20); Group I: D.T. light post (RTD) and Variolink II (Ivoclare vivadent), Group II: D.T. light post (RTD) and RelyX U100 (3M ESPE), Group III: Glassix post (Nordin) and Variolink II (Ivoclare vivadent) and Group IV: Glassix post (Nordin) and RelyX U100 (3M ESPE). Each root was sectioned to get slices of 2 ± 0.05-mm thickness. Push-out tests were performed using a triaxial loading frame. To express bond strength in megapascals (Mpa), load value recorded in Newton (N) was divided by the area of the bonded interface. After testing the push-out strengths, the samples were analyzed under a stereomicroscope.Results:The mean values of the push-out bond strength show that Group I and Group III had significantly higher values than Group II and Group IV. The most common mode of failure observed was adhesive between dentin and luting material and between post and luting material.Conclusions:The mean push-out bond strengths were higher for Groups I and III where Variolink II resin cement was used for luting the fiber post, which is based on the total etch adhesive approach. In most of the samples, failure was observed between cement–dentine interface, followed by post–cement interface, which shows difficulty in bonding between post–cement–dentine interface.

Cimentação adesiva de pinos fibrorreforçados

The adhesively bonded fiber reinforced composite posts (FRCP) play an important role in the contemporary restorative dentistry treatment, being considered as substitutes for prefabricated or cast metal posts. The aim of this article is to review the existing literature regarding FRCP, the available cement options and their adhesive strategy, along with the inherent difficulties to root canal cementation.

Restoration of endodontically treated teeth with major hard tissue loss – bond strength of conventionally and adhesively luted fiber‐reinforced composite posts

To evaluate the influence of the luting system on the pull-out bond strength of conventionally and adhesively luted fiber-reinforced composite posts (FRCPs). One hundred extracted bovine teeth (Di 3) were endodontically treated and randomly assigned to nine test groups and one control group (n = 10) according to luting system. After preparing the post cavities (8 mm), the custom-made FRCPs were inserted using conventional glass-ionomer cement (Ketac Cem), resin-reinforced glass-ionomer cement (Meron Plus and Fuji Plus), self-adhesive resin cement (RelyX Unicem and BisCem), self-conditioning adhesive and resin cement [Multilink Primer + Multilink and AdheSE + DC Activator + MultiCore Flow, or etch-and-rinse adhesive and resin cement (SealBond Ultima + CoreCem, and LuxaBond + LuxaCore Z). As a control, custom-made titanium posts were inserted with Ketac Cem. After water storage (37°C, 24 h, dark), the pull-out test was performed, followed by failure mode evaluation. The data were statistically analyzed (α = 0.05) using analysis of variance and the Dunnett T3 post hoc test. Luting system type and identity significantly influenced bond strength (P < 0.001); the bond strengths of all luting systems except Ketac Cem, MeronPlus, and BisCem were significantly higher than the control (4.4 ± 1.1 MPa). RelyX Unicem (12.0 ± 3.0 MPa) and LB + LCZ (14.8 ± 2.3 MPa) generated the highest bond strengths. The clinical application was demonstrated by restoring a traumatized tooth with extensive coronal destruction and thin root canal walls, using a FRCP combined with direct composite build-up. Luting system selection significantly influenced the bond strength of conventionally and adhesively luted FRCPs to bovine root canal dentin.

Stress behavior of cemented fiber-reinforced composite and titanium posts in the upper central incisor according to the post length: Two-dimensional finite element analysis

Background/purposeThis study examined the stress distribution in endodontically treated maxillary central incisors restored with various lengths of either titanium or fiber-reinforced composite (FRC) post-and-core systems, using two-dimensional finite element analysis models. Materials and methodsEight models of the maxillary central incisor were formed, surrounded by cortical bone, cancellous bone, and the periodontal ligament. Two different post-and-core systems, titanium and FRC posts (D.T Light Post), were modeled. In each restorative system, four models were designed by changing the post lengths cemented to the root at 10 mm, 9 mm, 8 mm, and 7 mm. A 100-N load was applied at a 45° angle to the long axis of each model. The stress distribution levels were calculated according to the Von Mises criteria. ResultsThe titanium post showed stress concentrations toward the post when loaded, and its stress concentration shifted toward the direction of the crown with a decreasing post length. In contrast, there was no stress concentration in the FRC post when loaded and no shift of the stress concentration toward the crown with a change in the post length. ConclusionResults suggest that the possibility of fracture of the FRC post is relatively low, compared to the titanium post, even for a short post. The same criteria for installation of a metal post should not be applied to an FRC post.

Fracture resistance of bone samples filled with fibre‐reinforced composite posts: an ex vivo model

To evaluate the strengthening effect of two different types of fibre-reinforced composite (FRC) posts in an ex vivo experimental model. Compact and hollow bone samples from bovine femurs were used as standardized samples. A total of 80 hollow samples were divided into two groups and filled either with a prefabricated FRC post or with individually adapted FRC posts. For each group, half of the samples were subjected to thermocycling (5-55 °C, 5000×). The remaining samples were kept for 24 h at 37 °C at 100% relative humidity. All samples were loaded diametrically until fracture. The null hypothesis tested was that the fracture resistance of standardized bone samples is not influenced by the type of FRC post, independently of the exposure to thermocycling. Results were evaluated by anova, and subsequent multiple comparisons were performed. The samples filled with the individually adapted FRC posts were more resistant to fracture than the prefabricated ones (P < 0.001), but this difference was not apparent in the thermocycled groups. Detachment of the posts upon fracture was highest after thermocycling for both groups, amounting to 55% and 95% for the individual adapted posts and the prefabricated posts, respectively. Initially, the samples filled with the individually adapted FRC posts were more resistant to fracture than those filled with the prefabricated ones. However, after ageing of the samples, both types of posts had similar strengthening effects.

Comparative Evaluation of Fracture Resistance under Static and Fatigue Loading of Endodontically Treated Teeth Restored with Carbon Fiber Posts, Glass Fiber Posts, and an Experimental Dentin Post System: An In Vitro Study

IntroductionThis investigation sought to compare the fracture resistance under static and fatigue loading of endodontically treated teeth restored with fiber-reinforced composite posts and experimental dentin posts milled from human root dentin by using computer-aided design/computer-aided manufacturing. MethodsSeventy maxillary central incisors were obturated and divided into 4 groups: control group without any post (n = 10), carbon fiber post group (n = 20), glass fiber post group (n = 20), and dentin post group (n = 20). Control group teeth were prepared to a height of 5 mm. In all other teeth, post space was prepared; a post was cemented, and a core build-up was provided. Half the samples from each group were statistically loaded until failure, and the remaining half were subjected to cyclic loading, followed by monostatic load until fracture. ResultsOne-way analysis of variance and Bonferroni multiple comparisons revealed a significant difference among test groups. The control group demonstrated highest fracture resistance (935.03 ± 33.53 N), followed by the dentin post group (793.12 ± 33.69 N), glass fiber post group (603.44 ± 46.67 N), and carbon fiber post group (497.19 ± 19.27 N) under static loading. These values reduced to 786.69 ± 29.64 N, 646.34 ± 26.56 N, 470 ± 36.34 N, and 379.71 ± 13.95 N, respectively, after cyclic loading. ConclusionsResults suggest that human dentin can serve as post material under static and fatigue loading. Although at an early stage in research, the use of dentin posts in root-filled teeth looks promising.

Compressive and flexural behaviour of fibre reinforced endodontic posts

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 26μm, 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.