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1.
The aim of this study was to evaluate the effect of different post‐space treatments on the push‐out bond strength and failure modes of glass fibre posts. Forty mandibular premolar roots were cut and endodontically treated. Post spaces were prepared and roots were divided into four groups. In group 1 distilled water irrigation (control), in group 2 2.25% NaOCl irrigation, in group 3 2.25% NaOCl + 17% EDTA irrigation were done and in group 4 diode laser was applied to the prepared post spaces. Scanning electron microscope (SEM) analysis was made for each group. Fibre posts were then luted with resin cement. Each root was prepared for push‐out test. Data were statistically analysed with anova (P = 0.05). After push‐out test, the failure modes were observed but not statistically analysed. There were statistically significant differences between Group 3 and Group 2 in both regions (P < 0.05), also in the middle region of Group 4 and Group 2 (P < 0.05). Cervical root segments showed higher bond strengths than middle ones in all groups (P < 0.05). The highest bond strength values were obtained from NaOCl/EDTA and the lowest bond strength values were obtained from NaOCl for both regions.  相似文献   

2.
The aim was to assess the influence of cement translucency on the retentive strength of luted fiber posts. Twenty extracted human premolars were randomly divided into four equal groups, based on the combinations of materials to be tested. Two post types of the same size, shape, and chemical composition, but different light‐transmission properties [Translucent post (TP) and Opaque post (OP)] were selected. The two post types were luted using the etch‐and‐rinse, light‐curing adhesive in combination with two shades of the same resin cement of markedly different light‐transmitting ability [Transparent shade (TS) and Opaque shade (OS)]. Early post retention was assessed using the thin‐slice push‐out test. Post type did not significantly influence post retention; however, cement translucency emerged as a relevant factor in intraradicular cementation, with the TS achieving higher push‐out strengths. The between‐factor interaction was also statistically significant; specifically, OP‐OS yielded significantly lower retentive strengths than all the other groups. Post translucency did not influence post retention, provided that a highly translucent cement was utilized for luting.  相似文献   

3.
Aim To evaluate the bond strengths of three adhesive/resin cement/fibre post systems to coronal, middle and apical thirds of post space dentine. Methodology Three types of glass‐fibre post systems were selected for the study. Saremco Post Non‐stop Fibre (Saremco), FRC Postec Plus (Ivoclar Vivadent) and Anatomical Post (Dentalica) were luted in prepared root canals using adhesive system and resin cement provided by the respective manufacturer. The luting agent was placed into the root canal using a specific syringe with needle. A push‐out test was performed on sections from the apical, middle and coronal parts of each specimen to measure bond strength. All fractured specimens were observed using a stereomicroscope to identify the modes of failure. Results Bond strength values were significantly affected both by the post–adhesive–cement system used and by root region (P < 0.05). Additionally, there was no significant interaction between the post system and region of canal factors (P > 0.05). The highest bond strength values were found in the coronal third for all experimental groups. The middle and apical thirds exhibited similar bond strengths with no statistically significant differences amongst them. Saremco and Precision post systems had the highest retentive strengths, whilst the Ivoclar post system had the lowest values. Microscopic analysis of the specimens revealed a prevalence of post–cement and mixed failures. Conclusions Type of post–adhesive–cement system and root position had a significant effect on fibre post retention. The coronal region of the canals was characterized by significantly higher bond strengths.  相似文献   

4.
Aim  To examine the effect of the application of an ethanol rinse before luting fibre posts to intraradicular dentine with etch-and-rinse adhesive systems by means of push-out bond strength evaluation and scanning electron microscopic (SEM) analysis.
Methodology  Fibre posts were luted to single-canal premolars using Dual Link as a luting agent in combination with a three-step (All Bond 2) or a two-step (One Step Plus) etch-and-rinse adhesive system, which were applied as per manufacturers' instructions (control) or with the additional rinse of ethanol on acid-etched dentine prior to the bonding procedures (experimental). Bonded specimens were sectioned into 1-mm-thick slabs and subjected to push-out bond strength testing. In addition, specimens from each group were processed for SEM analysis. Data were analysed by Kruskal–Wallis followed by Dunn's post hoc test at P  = 0.05.
Results  Push-out bond strength of All Bond 2 was significantly increased if the adhesive was applied on ethanol-saturated dentine ( P  < 0.05), whilst no significant difference ( P  > 0.05) was detected amongst experimental and control groups for One Step Plus. Irrespective of the adhesive, the SEM analysis revealed good impregnation patterns when both bonding techniques were employed.
Conclusions  The use of the additional ethanol rinse on acid-etched dentine revealed higher bond strength of All Bond 2 when compared with the control application procedure, used in combination with a resin-based cement to lute fibre posts into the dowel space. However, no bond strength improvements were detected using One Step Plus. Further investigations are needed to develop a clinically applicable ethanol/bonding/luting technique.  相似文献   

5.
This study was undertaken to examine the effect of eugenol-containing and non-eugenol-containing root canal sealers on the retention strength of glass fibre endodontic posts (ParaPost Fibre White) luted with a resin cement (ParaPost cement). We also examined the mode of failure that occurred visually by using scanning electron microscopy. Seventy-two single rooted, recently extracted, premolar teeth were root canal treated and randomly divided into two groups. Group 1 was obturated with gutta percha and a calcium hydroxide-based sealer (Sealapex, Kerr). Group 2 was obturated with gutta percha and a eugenol-based sealer (Tubli-Seal Kerr). The teeth were stored for 1 week in distilled water at 37 degrees C and then prepared for 9 mm posts with a 1.40-mm drill. The matching glass fibre post was luted with a resin cement following the manufacturer's instructions. The samples were stored for 1 week and thermocycled. The posts were removed from the root canals using a calibrated testing machine in tensile mode. The mean dislodging force for group 1 was 190.46 N and for group 2 was 183.8 N, with standard deviations of 54.9 and 56.0 N respectively. The t-test indicated no significant difference between the two groups. Failure of the posts occurred mainly within the resin layer. This study showed that under experimental conditions there was no statistically significant difference between Sealapex sealer and Tubli-Seal sealer on the retention of glass fibre posts using a resin cement.  相似文献   

6.
Retention and failure morphology of prefabricated posts   总被引:4,自引:0,他引:4  
PURPOSE: This study evaluated the effect of cement, post material, surface treatment, and shape (1) on the retention of posts luted in the root canals of extracted human teeth and (2) on the failure morphology. MATERIALS AND METHODS: Posts of titanium alloy (ParaPost XH), glass fiber (ParaPost Fiber White), and zirconia (Cerapost) received one of several surface treatments-sandblasting, CoJet treatment, application of Metalprimer II, or sandblasting followed by silane application-and were then luted in the prepared root canal of human incisors and canines (n = 10). Following water storage at 37 degrees C for 7 days, retention was determined by extraction of the posts. Failure morphology of extracted posts was analyzed and quantified stereomicroscopically. RESULTS: Type of luting cement, post material, and shape of post influenced the retention and failure morphology of the posts. Because of limited adherence of the cement to the root canal, surface treatments did not always have a positive effect on retention. CONCLUSION: Choice of luting cement was critical for all three types of posts. Parallel posts showed superior retention to tapered posts.  相似文献   

7.
OBJECTIVES: To determine the influence of post type and luting material on bond strength to dentin. METHODS: The root canals of extracted human upper central incisors were instrumented and post space was prepared using the respective drills for each post system. Glass fiber posts (Luscent Anchor, Dentatus [LA]) were luted using three dual-curing adhesive systems (Excite DSC/Variolink II, Vivadent [VL2]; EnaBond/EnaCem, Micerium [ENA]; Prime & Bond NT/Calibra, DentSply DeTrey [CAL]). A different brand of glass fiber post (EasyPost, DentSply Maillefer [EP]) and quartz fiber post (DT Light Post, VDW [DT]) were luted using CAL. Gold posts (Perma-dor, VDW) were luted either adhesively following tribo-chemical silicate coating (Rocatec, ESPE-Sil, 3M ESPE; CAL) or conventionally using glass ionomer cement (Ketac Cem, 3M ESPE). Three slices of 2mm height were cut perpendicular to the post from each restored root. Bond strength was determined by pushing out the post using a universal testing machine (/1449, Zwick). RESULTS: For all experimental groups combined, bond strength increased from the coronal to the apical section (Friedman test: P<0.001). Significant differences were observed among the fiber posts (DT/CAL>LA/CAL; Mann-Whitney U-test with Bonferroni-Holm adjustment: P<0.05; EP/CAL ranging in between) but not among luting materials (LA/VL2, LA/ENA, LA/CAL: n.s.). The gold posts were equivalent to DT/CAL with both luting procedures. SIGNIFICANCE: Selection of post type may be more important for bond strength than luting material. Bond strength of fiber posts was equivalent but not superior to adhesively or conventionally luted gold posts.  相似文献   

8.
STATEMENT OF PROBLEM: Cements that yield high retentive values are believed to allow use of shorter posts. PURPOSE: This study investigated the use of reinforced composite resin cement as compensation for reduced dowel length. MATERIAL AND METHODS: The retention values of stainless steel posts (parallel-sided ParaPost and tapered Dentatus in 5-, 8-, and 10-mm lengths) luted with Flexi-Flow titanium-reinforced composite resin and zinc phosphate cements were evaluated. Single-rooted extracted human teeth with crowns (n = 120), removed at the cementoenamel junction, were randomly divided into 4 groups of 30 samples each. Different post lengths were luted with either Flexi-Flow or zinc phosphate. Each sample was placed into a specialized jig and on a tensile testing machine with a crosshead speed of 2 mm/min, applied until failure. The effect of different posts and cements on the force required to dislodge the dowels was evaluated with multiple analyses of variance (ANOVA). One-way ANOVA with Scheffé contrast was applied to determine the effect of different post lengths on the retentive failure of posts luted with the 2 agents. RESULTS: Flexi-Flow reinforced composite resin cement significantly increased retention of ParaPost and Dentatus dowels (P<.001) compared with zinc phosphate. One-way ANOVA revealed no statistically significant difference (P>.05) between mean retention of both dowels luted with Flexi-Flow for all posts length used (5 mm = 8 mm = 10 mm). Mean retention values of the groups luted with zinc phosphate showed a statistically significant difference (P<.001) for the different post lengths (10 > 8 > 5 mm). Parallel-sided ParaPost dowels demonstrated a higher mean retention than tapered Dentatus dowels (P<.001). CONCLUSION: In this study, Flexi-Flow reinforced composite resin cement compensated for the reduced length of shorter parallel-sided ParaPost and tapered Dentatus dowels.  相似文献   

9.
Irrigation after post space preparation and its effects on the bond strength of different adhesive strategies are still an issue of interest. The aim of the present study was to investigate the effects of various irrigation protocols (IPs) on the push‐out bond strengths of fiber posts. One‐hundred and fifty extracted human anterior teeth were divided into three groups (= 50 each) and endodontically treated. The post space was irrigated before post placement using the following five IPs in each group: IP1 (control): 5 ml of distilled water; IP2: 5.25% sodium hypochlorite (NaOCl) applied with passive ultrasonic irrigation (PUI); IP3: 1% NaOCl applied with PUI; IP4: 18% ethylenediaminetetracetic acid (EDTA) followed by 5.25% NaOCl; and IP5: 2% chlorhexidine (CHX). Fiber posts placement in each group was performed using three different adhesive strategies. A self‐etch adhesive system revealed higher bond strength (16.2 ± 6.9 MPa) compared with an etch‐and‐rinse adhesive (8.5 ± 4.2 MPa) and a self‐adhesive resin cement (9.2 ± 4.7 MPa). The use of 18% EDTA/5.25% NaOCl increased the bond strength of the self‐adhesive resin cement. Conversely, this IP decreased the bond strength for the etch‐and‐rinse adhesive system, whilst 1% NaOCl enhanced the bond strength for the same system. Consequently, each adhesive strategy may need to be adapted to a specific IP.  相似文献   

10.
The effect of post-space treatment on the retention of fiber posts in different root regions was evaluated using two self-etching systems. Post spaces were prepared in extracted premolars and then the root canals were subjected to one of the following post-space treatments: (i) water irrigation (control); (ii) etching with 35% phosphoric acid for 30 s; (iii) irrigation with 17% EDTA followed by 5.25% sodium hypochlorite (NaOCl); and (iv) ultrasonic agitation associated with 17% EDTA and 5.25% NaOCl irrigating solutions. The dentin surfaces were examined under scanning electron microscopy (SEM) after different post-space treatments. Fiber posts were then luted in the treated roots using resin cement with either Clearfil SE Bond or Clearfil DC Bond, and the thin-slice push-out test was performed. Scanning electron microscopy showed that all the post-space treatments tested were effective in removal of the smear layer of debris, or sealer/gutta-percha remnants, on the root canal. The apical push-out strength was affected by post-space treatment. Both 35% phosphoric acid etching and ultrasonic agitation in combination with EDTA/NaOCl irrigation improved the apical push-out strength of the fiber post, regardless of the type of self-etching system. A solo irrigation with an EDTA/NaOCl solution resulted in a lower apical push-out strength compared with the other two experimental groups.  相似文献   

11.
By means of a pull-out test, this study compared the retentive force of three fiber-reinforced resin composite posts and a zirconia post. These posts were cemented using two different dual-polymerizing adhesive resin luting agents. Forty freshly extracted canines were selected for the study. All tooth root were endodontically treated and the post spaces prepared. The posts were luted using luting agents according to the manufacturers' guidelines. A tensile force was applied, and all data were collected and analyzed statistically. Glass fiber posts that were luted with Panavia F (Group 3) had the highest median load (3.610 N), while zirconia posts that were luted with RelyX ARC (Group 8) had the lowest median load (0.926 N). Among the different post systems that were luted with Rely X ARC, significant differences were observed in their median tensile loads (p < 0.047). When comparing between Panavia F and RelyX ARC of each post system, a significantly higher tensile load was seen with zirconia posts luted with Panavia F (Group 7) (p < 0.032).  相似文献   

12.
The aim of this study was to investigate the effects of the application of gaseous ozone and Nd:YAG laser on glass‐fibre post bond strength. Forty‐two madibular premolar roots were cut, endodontically instrumented and irrigated with 2.5% NaOCl. Post spaces were prepared and roots were divided into three groups (n = 14). The antimicrobial pretreatment was conducted as follows: gaseous ozone, Nd:YAG laser and control (no additional disinfection methods). Scanning electron microscope analysis was made for each group (n = 2). A resin cement was used for luting the posts. For push‐out test, each root was cut horizontally (two cervical, two middle and two apical). Statistical analyses were performed with one‐way anova (α = 0.05). Fracture types were observed. There was no statistically significant difference between the groups (P > 0.05). There were statistically significant differences in cervical and apical segments of laser and control groups (P < 0.05). The disinfection of the post spaces with Nd:YAG laser and ozone had no adverse effects on bond strength of glass‐fibre post.  相似文献   

13.
The adhesion of fiber posts luted with simplified adhesive systems has been a matter of great interest over the past years. The aim of this study was to assess the post retentive potential of experimental self‐adhesive resin cement (EXP) when used alone and in combination with a self‐etch adhesive. Fiber posts were placed in endodontically treated teeth and divided into four groups (n = 6) according the luting material, as follows: group 1 (EXP alone); group 2 (EXP used with self‐etch adhesive); group 3 (marketed dual‐cured cement used with self‐etch adhesive); and group 4 (marketed self‐adhesive cement). The push‐out test was used to assess the retentive strength of fiber posts (expressed in MPa), and specimens were analyzed under a stereomicroscope to determine failure mode. The adhesive interface between the cement and root canal dentin for each group was evaluated using scanning electron microscopy. The post retentive potential of group 1 (EXP) (7.48 ± 4.35 MPa) was comparable with that of marketed cements from group 4 (6.79 ± 3.68 MPa) and group 3 (8.77 ± 4.58 MPa). When EXP was used in combination with self‐etch adhesive (group 2), significantly higher push‐out bond‐strength values were measured (15.87 ± 4.68 MPa) compared with the other groups.  相似文献   

14.
Post and core systems anchored and supported by endodontic files, Para Posts, Boston Posts and Flexi Posts were subjected to tensile testing in an Instron testing machine. All forces were applied to the cores until the post-core system was removed. The test results revealed no statistically significant difference among post and core systems built up with Para Posts, Boston Posts or Flexi Posts. The endodontic files proved to be significantly less retentive than the other post systems evaluated. Under the conditions of this study, the use of endodontic files as retentive posts is not supported.  相似文献   

15.
PURPOSE: To evaluate the effect of luting systems and root region on the push-out bond strengths of a glass fiber-reinforced post and a zirconia post. METHODS: Thirty-two extracted human anterior teeth (central incisors and canines) were endodontically treated with lateral condensation of gutta percha and AH26 sealer. Teeth were randomly assigned to eight groups (n = 4 per group). Two post systems from the same manufacturer (Cosmopost, a zirconia post; or FRC Postec, a glass fiber-reinforced post) were placed with a luting system (bonding agent and resin luting agent). C-Post was cemented with One-Step and Post Cement Hi-X was used as the light-polymerized adhesive control. ParaPost Fiber White cemented with ParaPost Adhesive and ParaPost Resin Cement was used as an auto-polymerized adhesive control. The roots were sectioned in equal thirds (apical, middle and cervical). A push-out test was performed in each section to measure regional bond strengths in MPa. Means were analyzed with two-way ANOVA and Duncan's post-hoc test (alpha = 0.05). RESULTS: The fiber posts ranked in the highest statistical subset regardless of the luting system: ParaPost Fiber White (self-cure control), FRC Postec bonded with Excite DSC/Variolink II, FRC Postec bonded with Syntac/Variolink II, FRC Postec bonded with Excite DSC/Experimental Self Cure Cement, and C-Post bonded with One Step/Hi-X. The zirconia post Cosmopost ranked in the lowest subsets regardless of the adhesive system used at P < 0.05. Means for the medium region of the root (5.0 +/- 0.8 MPa) were not statistically different from those obtained either in the cervical or in the apical region. Means for the cervical root region (6.2 +/- 0.9 MPa) were statistically higher than those of the apical region (4.5 +/- 1.1 MPa) at P < 0.001.  相似文献   

16.
目的评价6种复合树脂粘接剂与带有半渗透网状复合基质的纤维增强型复合树脂根管桩的粘接强度。方法实验分为6组,分别为纤维增强型复合树脂根管桩和6种复合树脂粘接剂模块,每组7个样本。用粘接树脂活化剂处理各组根管桩表面5min,将粘接剂模块粘接到根管桩表面并固化,37℃下储存各组样本20h后,万能实验机进行剪切粘接强度测定。结果6种不同复合树脂粘接剂与纤维增强型复合树脂根管桩粘接后,各组根管桩表面剪切粘接强度之间的差异无统计学意义(F=2.32,P=0.45)。结论6种复合树脂粘接剂均适用于纤维增强型复合树脂根管桩的粘接。  相似文献   

17.
The aim of this study was to evaluate the effect of maleic acid (MA) on both the bond strength of fibre post to root dentine and smear layer removal after post space preparation. Sixty, single‐canal premolars were endodontically treated and randomly assigned to four groups: group 1 [0.9% saline solution (control]); group 2 [2.5% sodium hypochlorite (NaOCl)]; group 3 [17% ethylenediaminetetraacetic acid (EDTA) followed by 2.5% NaOCl]; and group 4 (7% MA followed by 2.5% NaOCl). Self‐adhesive resin cement was used to test the adhesion of a glass‐fibre post to the root dentine through a micropush‐out test. Scanning electron microscopy was performed to examine and score the treated specimens for smear layer removal, and stereomicroscopy was applied to investigate the failure modes of fibre posts. Maleic acid exhibited the highest mean bond‐strength values in the apical regions among all the groups. Most failure modes (31.9%) were adhesive‐type failures between the dentine and luting materials. Maleic acid performed statistically significantly better than the other groups regarding smear layer removal, especially in the apical region. Maleic acid is an effective irrigant that can remove the smear layer, open dentinal tubules, and act as a high‐efficiency final irrigant in activation protocols.  相似文献   

18.
Retention of prefabricated and individually cast root canal posts in vitro   总被引:2,自引:0,他引:2  
Hedlund SO  Johansson NG  Sjögren G 《British dental journal》2003,195(3):155-8; discussion 147
OBJECTIVES: The aim of the study was to evaluate the retention of prefabricated root canal posts made of a variety of materials that have recently been introduced into dentistry. MATERIALS AND METHODS: The posts studied were CosmoPost, Composipost carbon fibres, Composipost Aestheti-Plus, Composipost Light-Post and Para Post Fiber White. The posts were luted in extracted human premolars and the cores were built up with the resin composites recommended by the manufacturers. The retention of individually cast gold alloy posts luted with zinc-phosphate cement were used as reference. A universal testing machine was used to determine the retention of each cemented post Data were compared using ANOVA supplemented with Fisher's PLSD at a significance level of p < 0.05. RESULTS: Only the CosmoPost system exhibited retention values that were significantly lower than for the conventionally cast gold alloy posts luted with zinc-phosphate cement The force necessary to loosen the CosmoPost specimens was significantly less than that needed to loosen the Composipost. Estheti-Plus (p < 0.05) and the Composipost Ught-Post systems (p < 0.001]. The force necessary to loosen the ParaPost Fiber White specimens was significantly less than for the Composipost Light-Post system (p < 0.01). Other combinations did not differ significantly (p > 0.05). CONCLUSIONS: When zirconium oxide ceramic posts are luted with resin composites the bonding between the ceramic and resin composite seems to be weak. Further studies are thus necessary to achieve improved retention of all-ceramic root canal posts.  相似文献   

19.
The purpose of this study was to evaluate the effect of silanization and light-irradiation on bonding between a fiber post and different resin-based luting agents. Sixty silicium fiber posts (Easy Post) were divided into 10 groups according to the type of resin-based luting agent employed, whether the post surface was silanized, whether the adhesive was light-irradiated, and whether Calibra luting agent was used. The micro-tensile bond strength and bonded interface of specimens in each group were evaluated. Specimens luted with Calibra or FluoroCore 2 resin-based luting agent systems were superior to those treated with Multilink or Variolink II, in terms of both bond strength and interfacial integrity. Application of silane, light-irradiation of the adhesive, or light-irradiation of the Calibra resin-based luting agent did not significantly increase the bond strength further. It can be concluded that Calibra or FluoroCore 2 resin-based luting agent systems are more suitable for luting prefabricated Easy Post in a clinical situation, while pre-silanization of the post surface and light-irradiation of XP Bond/SCA adhesive or resin-based luting agent may not be as important as hitherto considered.  相似文献   

20.

Objectives

To assess by means of push-out test the post retentive potential of a new flowable resin composite with low polymerization stress.

Methods

SureFil® SDR™ (Dentsply, S) was compared with the resin cement Calibra (Dentsply, C). S and C were used in combination with the adhesive XP Bond (Dentsply, XPB). In C group the Self-Cure Activator was mixed with XPB. The following types of fibre posts were luted into 30 extracted premolars: Radix Fiber Post (Dentsply, R), DT Light Post (RTD, LP), ER Dentin Post (Komet, ER), DT Light SL (VDW, SL), FibreKleer (Jeneric Pentron, F). Six posted roots per group were tested. Each root provided three to five 1 mm-thick slices. Measured push-out strengths were differentiated by post space level and statistically analysed (p < 0.05). The failure mode of each debonded specimen was assessed.

Results

Cement type did not have a significant effect on post retention (p = 0.54). Post type was a significant factor for push-out strength (p < 0.001). LP exhibited significantly higher retentive strength than SL and F; push-out strengths of ER and R were significantly higher than those of F. Post retention was significantly influenced by post space level (p < 0.001). Significantly higher push-out strengths were recorded at the coronal third than at the middle and apical levels. The post–cement interaction was significant (p = 0.002). Posts luted with S most often failed at the cement–post interface.

Conclusions

When the new flowable low-stress composite was used to lute fibre posts, similar retentive strengths to those of a marketed cement from the same manufacturer were achieved.

Clinical significance

SureFil® SDR™, a flowable composite originally proposed for bulk filling of posterior restorations, exhibited post retentive strengths similar to those of a cement by the same manufacturer. With a relatively high filler load, yet a low curing stress, SureFil® SDR™ may be adequate for both post cementation and core build-up.  相似文献   

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