四种粘结材料对纤维桩在不同深度根管内的固位力的影响——薄片推出实验

目的:比较4种不同树脂粘结材料在不同深度根管内粘固纤维桩的推出强度。方法:28个单根管离体前牙截冠后行根管充填和桩道预备,随机分为4组,分别用不同的粘结材料(Ⅰ:XP Bond-Dual Cure Calibra resincement;Ⅱ:XP Bond-Dual Cure Fluorocore2;Ⅲ:Excite DSC MultiCore Flow;Ⅳ:Multilink Primer A/B MultilinkAutomix)粘固纤维桩。粘固了纤维桩的牙根切割为1mm厚的试件并将其按照根管的深度分为上部、中部和下部3组,测试其推出强度。结果:Ⅰ组、Ⅱ组上部的推出强度均显著高于下部(P<0.05),Ⅲ组、Ⅳ组的推出强度在不同深度根管间无显著性差异(P>0.05)。结论:材料的类型和根管的深度对纤维桩的固位有影响。     

不同粘接剂对二氧化锆桩固位力的影响

目的探讨不同粘接剂对二氧化锆桩与根管内牙本质粘接强度的影响。方法将60颗完整无龋坏的离体上颌中切牙自釉牙骨质界处截断牙冠,根管桩道预备,制作二氧化锆桩核。60颗牙随机分为6组,分别用磷酸锌水门汀、聚羧酸锌水门汀、玻璃离子水门汀i、Bond加LuxaCore双固化树脂、RelyX Unicem树脂、32%磷酸加ESPE RelyX Unicem树脂粘固二氧化锆桩核。万能力学试验机进行推出测试,记录粘接强度,并对数据行统计学分析。结果 32%磷酸加ESPE RelyX Unicem树脂组、ESPE RelyX Unicem树脂组i、Bond加Luxa Core树脂组、聚羧酸锌水门汀组、玻璃离子水门汀组、磷酸锌水门汀组的二氧化锆桩粘接强度分别为（15.06±1.80）MPa、（11.57±1.33）MPa（、10.42±1.24）MPa（、7.30±1.05）MPa（、6.99±0.87）MPa（、3.97±0.95）MPa,固位力依次降低。其中32%磷酸加ESPE RelyX Unicem树脂组的固位力显著高于其他组,两两比较差异均有统计学意义（P〈0.05）;ESPE RelyX Unicem树脂组与Luxa Core树脂组之间（P=0.590）,聚羧酸锌组和玻璃离子组之间（P=0.490）的差异均无统计学意义;磷酸锌水门汀的粘接强度最低,与其它组比较差异均有统计学意义（P〈0.05）。结论临床粘固二氧化锆桩,树脂类粘接剂固位力较强,自粘接系统加用酸蚀技术可以显著提高二氧化锆桩在根管内的粘接强度。     

不同参数激光处理根管对纤维桩粘结强度影响的实验研究

目的:研究不同参数Er:YAG激光处理根管壁牙本质对纤维桩粘结强度的影响,为激光临床应用提供参考。方法:收集60颗人类上颌中切牙,根据不同处理方法随机分为5组;空白对照组;3 W-50 μs Er:YAG激光组;3 W-100 μs Er:YAG 激光组;4.5 W-50 μs Er:YAG激光组;4.5 W-100 μs Er:YAG激光组,每组12颗。离体牙根管预备,充填,桩道预备后,Bisco树脂加强型纤维桩通过RelyX^TM Unicem粘结树脂水门汀粘固于根管内。流水状态下慢速锯将纤维桩外周平行片切,再垂直粘结面片于试件1 mm、4 mm、7 mm处切成三段1.0 mm×1.0 mm的长方形柱状试件,进行微拉伸强度测试。不同根管处理方法与牙根不同区域微拉伸强度均数采用两因素方差分析(α=0.05)。电镜下进行断裂类型分析,组件不同类型断裂率采用χ²检验(α=0.05)。 结果:3 W10-100 μs Er:YAG组拉伸强度值最高(5.55±0.97) MPa,与对照组(4.06±1.22) MPa相比较差异有显著性(P＜0.05) 。根管上部和中部粘结强度高于根管下部,差异有显著性(P＜0.05)。结论:Er:YAG激光处理牙本质表面对其与纤维桩粘结强度的影响与激光功率大小和脉冲持续时间有关,3 W-100 μs Er:YAG激光处理表面可以显著增强纤维桩与根管牙本质的粘结强度。     

离体牙经不同根管封闭剂充填后纤维桩剪切粘结强度的对比研究

目的：研究不同根管封闭剂对两种纤维桩固位力的影响。方法：24颗离体上颌中切牙,截冠、预备根管,按根管封闭材料及纤维桩不同均分为4组。C-RP组：Cortisomol丁香酚类封闭剂,Rebilda Post纤维桩;C-ML组：Cortisomol封闭剂,Mac-rolockTM Post纤维桩;G-RP组：Guttaflow非丁香酚类封闭剂,Rebilda Post纤维桩;G-ML组：Guttaflow封闭剂,MacrolockTM Post纤维桩。自酸蚀粘结剂将纤维桩粘固,牙根切成1.5 mm薄片,行薄片推出实验,并观察断裂模式。扫描电镜观察粘结界面的显微结构。结果：C-RP、C-ML、G-RP、G-ML 4组剪切粘结强度（MPa）分别为5.89±2.89、7.46±2.71、7.66±3.00、9.24±3.03,C-RP粘结强度最低（P〈0.05）。牙根颈、中、根尖部的剪切粘结强度依次降低（P〈0.01）。扫描电镜观察：相比根尖部,颈部有明显树脂突;使用Guttaflow封闭剂组混合层厚度以及树脂突数目、长度优于使用Cortisomol组。结论：使用丁香酚类根管封闭会降低纤维桩剪切粘结强度;纤维桩修复后根尖部的粘结强度有待增强。     

表面处理及不同水门汀材料对纤维桩粘固性能影响的研究

目的：评价酸蚀一喷砂处理以及4种不同水门汀材料Fuji I（FUI）、Fuji Cem（FUC）、RelyX Unicem（RX—U）、RelyXARC（RXA））对纤维桩粘固性能的影响。方法：选取80颗无龋坏单根管人前磨牙,根据对应纤维桩表面处理与否随机分为2组,进而根据粘接材料的不同分为4个亚组。常规根管充填和桩道预备后,分别选用4种水门汀材料将表面处理前后的玻璃纤维桩粘接到预备根管内;观察纤维桩表面及每组试件粘接界面扫描电镜（SEM）下微观形貌,测试即刻拉出强度（pull—outtest）。结果：表面处理前后纤维桩的各水门汀材料拉出强度以RXA组最高,随后依次为RXU、FUC、FUI组,且各组间均相差显著（P〈0．05）;纤维桩表面处理后与各水门汀材料的拉出强度较之处理前均显著提高（P〈0．05）：SEM观察显示：表面处理后纤维桩的表面粗糙度纤维暴露数量均有明显增加;表面处理前后各组粘接界面微观形貌存在差异,各组的粘接界面均较处理前更致密。结论：酸蚀一喷砂处理纤维桩表面后可以提高其与不同水门汀材料的粘接固位力。     

不同粘固材料对纤维桩固位力的影响

目的：研究纤维桩钉在用5种不同粘固材料的固位力,为临床选择纤维桩粘固材料提供依据。方法：将纤维桩用5种粘固材料（HY-BOND玻璃离子水门汀;PermaCem双固化树脂水门汀;LuxaCore双固化树脂;Dulink双固化树脂水门汀;Rely-X Unicem双固化树脂水门汀）粘固于离体人牙根管内,万能电子力学试验机测试其固位力,电子探针分析界面情况。结果：纤维桩在用不同粘固材料的固位力由大到小顺序为：Dulink组、PermaCem组、LuxaCore组、Rely-X Unicem组、HY—BOND玻璃离子组,各组间固位力有显著性差异（P〈0．05）。结论：不同类型粘固材料对纤维桩的粘结力不同,树脂水门汀固位力优于玻璃离子水门汀,且显示了良好的粘结完整性。     

两种预成桩拉伸固位强度的体外研究

目的:比较用树脂粘接剂粘接的纤维增强复合树脂预成桩与用磷酸锌粘固的不锈钢预成桩的拉伸固位强度。方法:选择40颗因正畸拔除的下颌前磨牙,用金刚砂片在距釉牙骨质界冠方1 mm处去除牙冠,随机均分为4组,用预成桩配套用车针预备9 mm深的桩腔。对于不锈钢桩组,桩腔预备的直径为1.25 mm,用磷酸锌粘固粉粘固。对于纤维增强复合树脂桩组,桩腔预备的直径分别为1.00 mm、1.25 mm、1.50 mm,用树脂粘接剂粘接。储存24 h后,置于拉伸强度检测机上测量各组样本预成桩的拉伸固位强度,加载速度为5.0mm/m in,对各组的测量结果进行统计学分析。结果:各组预成桩的平均固位强度在(43.9±10.4)kg至(19.9±5.7)kg之间,磷酸锌粘固的不锈钢桩组的拉伸固位强度显著高于所有纤维桩组,1.00 mm纤维增强复合树脂桩组的固位强度明显低于其它组。结论:在本实验的研究条件下,磷酸锌粘固的不锈钢桩组固位强度最高。     

不同间隔时间预备不同桩核系统对桩核微渗漏的影响

目的：研究不同间隔时间预备不同桩核系统对微渗漏的影响.方法：收集因正畸需要拔除的132颗下颌单根前磨牙,进行根管治疗、根管预备和桩核制作及粘结.132颗牙随机分为4组,分别在桩核粘固后5 min、15 min、30 min、24 h,阴性对照组进行牙体预备,每组内再随机分为铸造桩核磷酸锌粘固、铸造桩核聚羧酸锌粘固和玻璃纤维桩核树脂粘固亚组.每一标本进行染色法评价微渗漏情况.结果：相同的桩核系统中,渗漏值随着桩核粘固间隔时间的延长而降低;相同的间隔时间下,5 min、15 min和24 h时,纤维桩核系统的渗漏值最小,与其它两组比较均有统计学意义（P＜0.05）,30 min时铸造桩核磷酸锌粘固组与纤维桩核系统组无统计学意义（P＞0.05）.结论：不同间隔时间预备不同桩核系统对桩核微渗漏值有影响,为了桩核的稳固,应尽量在桩核粘固24 h后进行牙体预备.     

不同黏结方法和不同桩道部位对纤维桩黏结强度的影响

目的:比较不同黏结方法在不同桩道部位对纤维桩黏结剪切强度的影响。方法:选取42颗离体上颌中切牙,根管治疗桩道预备后根据不同的黏结方法随机分为6组,Ⅰ组为全酸蚀黏结剂Luxabond+自黏结树脂水门汀Rely X TM Unicem,Ⅱ组为全酸蚀黏结剂Luxabond+双固化树脂水门汀Luxacore,Ⅲ组为自酸蚀黏结剂Contax+自黏结树脂水门汀 Rely X TM Unicem,Ⅳ组为自酸蚀黏结剂Contax+双固化树脂水门汀Luxacore,Ⅴ组为自黏结树脂水门汀Rely X TM Unicem,Ⅵ组为双固化树脂水门汀Luxacore。纤维桩黏固后行薄片推出实验,并在扫描电镜下观察黏结界面及根管内壁的微观形态。采用SPSS13.0软件包对数据进行统计学分析。结果:不同黏结方法纤维桩的黏结强度差异具有显著性(P<0.05),第Ⅰ组和第Ⅲ组的黏结强度最高。扫描电镜观察,Ⅰ组和Ⅱ组的黏结界面有树脂突形成,黏结界面也更加致密。结论:自黏结树脂水门汀Rely XTM Unicem若配合使用全酸蚀及自酸蚀黏结剂,可显著提高纤维桩的黏结强度。     

桩道牙本质壁的不同处理对纤维桩粘接强度的影响

目的：比较使用自粘接型树脂水门汀粘接纤维桩时,经3种不同方法处理桩道牙本质壁后对纤维桩粘接强度的影响。方法：收集30颗因正畸需拔除的健康下颌单根管前磨牙进行截冠、常规根管治疗、桩道预备后随机分为3组,每组10颗;使用不同方法对桩道牙本质壁进行处理：Ⅰ组(对照组)：手动注射器冲洗;Ⅱ组(超声组)：超声冲洗;Ⅲ组(激光组)： Er： YAG激光冲洗。使用自粘接桩核树脂水门汀将纤维桩粘接完毕后切片进行薄片推出实验。采用双因素方差分析检验桩道牙本质壁的不同处理方法及桩道的不同深度(根颈部,根中部,根尖部)对纤维桩粘接强度的影响,并用万能显微镜观察试件的破坏方式,对结果进行Chi-Square检验。设定检验标准α=0.05。结果：各组粘接强度差异有统计学意义,Ⅱ组和Ⅲ组的粘接强度显著高于Ⅰ组(P<0.05),桩道不同深度纤维桩的粘接强度差异无统计学意义(P=0.082);各组破坏方式以混合破坏为主,但Ⅱ组和Ⅲ组中桩道牙本质壁—树脂水门汀破坏比例较Ⅰ组明显降低。结论：使用自粘接型树脂水门汀时,经超声或激光处理预备后的桩道可显著提高纤维桩的粘接强度。桩道深度对纤维桩的粘接强度无影响。     

Effect of curing modes of dual-curing luting systems and root regions on retention of translucent fiber posts in root canals

PURPOSE: To evaluate the effect of different curing modes of dual-curing luting systems and root regions on the push-out strength of fiber posts to intraradicular dentin. MATERIALS AND METHODS: Forty-two extracted premolars with a single root canal were sectioned at the cementoenamel junction and the roots were endodontically treated. The roots were divided into two groups according to two dual-curing luting systems: (1) XP BOND-Dual Cure/Calibra resin cement; (2) XP BOND-Dual Cure/FluoroCore 2. For each luting system, three different curing modes were applied to the dentin adhesive and resin cement: "Self-cure and Self-cure (SC&SC)", "Self-cure and Dual-cure (SC&DC)", and "Dual-cure and Dual-cure (DC&DC)". Translucent Easy fiber posts (Dentsply Maillefer) were luted in the roots. A thin-slice push-out test was performed, and the data of push-out strength were analyzed using three-way ANOVA with luting system, curing mode, and root region (apical, middle and coronal) as factors. Tukey's test was used for post-hoc comparisons. RESULTS: The push-out strength of XP BOND-Dual Cure/Calibra was significantly lower when Calibra resin cement was self-cured than when it was dual-cured (SC&SC: 6.04 +/- 2.65 MPa; SC&DC: 10.69 +/- 3.01 MPa; DC&DC: 10.72 +/- 3.63 MPa; p < 0.05). The curing modes did not affect the push-out strength of XP BOND-Dual Cure/FluoroCore 2 (SC&SC: 7.90 +/- 3.94 MPa; SC&DC: 8.32 +/- 2.73 MPa; DC&DC: 9.27 +/- 4.12 MPa; p > 0.05). The coronal push-out strength was significantly higher than the apical push-out strength (p < 0.05). CONCLUSION: Retention of fiber posts in root canals was affected by the curing modes of dual-curing luting system and root regions.     

Push-out bond strengths of endodontic posts bonded with different resin-based luting cements

PURPOSE: To compare the push-out bond strengths of endodontic posts bonded with different resin-based luting cements and to verify that bond strengths did not vary with cement thickness. METHODS: 48 root canals were shaped using 6% NiTi rotary files, obturated with gutta-percha and AH Plus sealer and prepared for post cementation using Panavia F, Parapost cement, SuperBond and Unicem Rely X. All roots were sectioned into 0.7 mm thick slices and digital photographs of each slice were analyzed using Scion Image to measure the surface area of the luting cement. The root slices were stressed to failure at 1 mm/minute using a push-out test. Push-out strength was calculated as the force at failure divided by the bonded surface area. Least squares linear regression analysis was used to assess the effect of cement thickness on bond strength. Fractured specimens were further observed under the SEM. RESULTS: Mean push-out bond strengths were: Panavia F (8.8 +/- 3.6 MPa), Parapost cement (9.1 +/- 4.4 MPa) SuperBond (14.6 +/- 2.9 MPa) and Rely X Unicem (12.4 +/- 3.3 MPa). The Panavia F and the Parapost cement were not significantly different from each other, but both were significantly lower (P < or = 0.05) than SuperBond and Rely X Unicem. Although there were large variations in cement thickness, the cementation of fiber posts with thicker cement layers did not affect the performance of the adhesive luting cements applied to root canal dentin.     

Morphological and bond strength evaluation of different resin cements to root dentin

This study correlated the morphological characteristics with the bond strengths of various resin cements used for bonding fiber posts to root canal dentin. Fifty glass-fiber posts (FRC Postec Plus) were luted into the root canals of extracted human anterior teeth using five resin cements ( n  = 10): Panavia F 2.0, PermaFlo DC, Variolink II, RelyX Unicem, and Clearfil Core. Before insertion of the post, the adhesive systems were labeled with fluorescein and the resin cement was labeled with rhodamine isothiocyanate. The roots were sectioned into three slices (of 2 mm thickness), and each slice was analyzed using confocal laser scanning microscopy in dual fluorescence mode to determine hybrid layer thickness, the number of resin tags, and the number of broken tags. Bond strengths were measured using a micro push-out test. Bond strengths to root canal dentin, as well as the morphological characteristics, were significantly affected by the materials. However, these factors did not correlate. The self-adhesive resin cement, which showed the formation of a hybrid layer and resin tags only sporadically, had the highest bond strengths. These results indicate that chemical interactions between the adhesive cement and hydroxyapatite may be more crucial for root dentin bonding than the ability of the same material to hybridize dentin.     

Regional bond strengths to root canal dentin of fiber posts luted with three cementation systems

This study evaluated the influence of the cementation system on the regional push-out bond strength and failure pattern of fiber posts to radicular dentin. The roots of 48 extracted human incisors were prepared and divided into 3 groups (n = 16), according to the cementation system: AdperScotchbond Multi-Purpose + resin cement RelyX ARC (SBMP+ARC); Adper SingleBond 2 + RelyX ARC (SB+ARC) and; RelyX U100 self-adhesive resin cement (U100). The posts were cemented as per manufacturer's instructions for each cementation system. After 1 week, the roots were sectioned transversely into 6 discs. Two discs were obtained from the cervical, middle and apical thirds and the push-out test was carried out. The failure pattern was examined on all debonded specimens. The data were analyzed by two-way repeated measures ANOVA and Tukey's test. When U100 was used, no statistically significant difference (p>0.05) was observed among the different root regions. Statistically higher push-out bond strength values were detected in the cervical third for SBMP+ARC and SB+ARC (p<0.05). The U100 showed significantly more mixed failures than SBMP+ARC in the apical third (p<0.05). In conclusion, the self-adhesive cement RelyX U100 was the only cement not sensitive to the root canal region.     

EFFECT OF RELINING ON FIBER POST RETENTION TO ROOT CANAL

One of the clinically relevant problems dentists face when restoring endodontically treated teeth is the mismatch between fiber post and post space diameters, which results in an excessively thick resin cement layer. Fiber post relining appears as a solution for this problem.

Objectives:

The aim of this study was to evaluate the effect of fiber post relining with composite resin on push-out bond strength.

Material and Methods:

Twenty bovine incisors were selected to assess post retention. The crowns were removed below the cementoenamel junction and the root canals were treated endodontically and flared with diamond burs. The roots were allocated into two groups (n=10): G1: fiber posts without relining and G2: fiber posts relined with composite resin. The posts were cemented with a dual-cured resin cement and the specimens were sectioned transversally. Three 1.5-mm thick slabs were obtained per root and identified as cervical, medium and apical thirds. The push-out test was performed at a crosshead speed of 0.5 mm/min until post dislodgement occurred. The failure mode of fractured specimens was analyzed under scanning electron microscopy. Data were analyzed by split-plot ANOVA and post-hoc Tukey''s test at a pre-set alpha of 0.05.

Results:

Relined fiber posts presented higher retention values than non-relined post in all thirds. No statistically significant differences (p>0.05) were found among thirds for relined posts. All failures occurred at the interface between resin cement and root dentin.

Conclusions:

Relining with composite resin seems to be an effective method to improve the retention of fiber posts to flared root canals.     

Effect of two fiber post types and two luting cement systems on regional post retention using the push-out test.

OBJECTIVE: To investigate regional root canal push-out bond strengths for two fiber-reinforced post types using two adhesive systems. METHODS: The crowns of 24 recently extracted sound maxillary central incisors were sectioned transversely 2 mm coronal to the labial cemento-enamel junction, and the roots treated endodontically. Following standardized post space preparations, fiber-reinforced posts (C-POST; AESTHETI-PLUS) were placed using two adhesive systems (acid-etch ONE-STEP PLUS/C&B CEMENT; self-adhesive RelyX Unicem), in four equal groups. Push-out bond strength tests were performed at four sites in each root. Results were analyzed using split-plot ANOVA, with a=0.05 for statistical significance. RESULTS: AESTHETI-PLUS quartz fiber-reinforced posts showed significantly higher push-out strengths than C-POST carbon fiber-reinforced posts (P<0.0001). The separate acid-etch adhesive system resulted in significantly higher bond strengths than the self-etch self-adhesive system (P<0.0001). Bond strengths decreased significantly from coronal to apical root canal regions (P<0.0001). SIGNIFICANCE: The quartz fiber-reinforced post placed using the separate acid-etch adhesive system provided significantly better post retention than the carbon fiber-reinforced post placed using the self-etch self-adhesive system.     

根管壁表面处理和不同粘结系统对纤维桩粘结强度的影响

目的研究不同根管牙本质壁表面处理方法及使用不同粘结系统对石英纤维桩粘结时根管不同部位剪切粘结强度的影响。方法36颗完整离体上中切牙唇侧釉牙骨质界冠方2.0mm处截冠后行根管治疗。专用钻根管预备,酸蚀后,分别采用生理盐水60s(对照组)、10%次氯酸钠(NaOCl)溶液60s、17%乙二胺四乙酸(EDTA)溶液60s与5.25%NaOCl溶液60s联用的根管壁处理方法,结合DUOLINK树脂粘结剂或LUXACORE核材料按析因设计配对行石英纤维桩粘结修复。包埋并切片后,置于MTSSynergie综合测试仪上采用1mm微推出法对不同根管段行剪切粘结实验,记录数值并行统计学分析。结果剪切粘结强度依次为(MPa):6.29±3.77,9.67±3.94,8.07±3.59,2.59±2.04,5.46±3.09,5.80±3.56。10%NaOCl处理组、17%EDTA溶液与5.25%NaOCl溶液联用组剪切粘结强度均明显增强(P<0.0001);DUOLINK树脂粘结剂组剪切粘结强度优于LUXACORE核材料组(P<0.0001);所有实验组中,剪切粘结强度自根管冠方向根方逐渐减弱。结论单独使用10%NaOCl溶液、17%EDTA溶液与5.25%NaOCl溶液联用处理根管壁增强了石英纤维桩修复根管不同部位尤其是根尖的剪切粘结强度。     

Effect of post-space treatment on retention of fiber posts in different root regions using two self-etching systems

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.     

Evaluation of the resin cement thicknesses and push-out bond strengths of circular and oval fiber posts in oval-shapes canals

PURPOSE

The aim of this study was to evaluate whether the push-out bond strength varies between oval and circular fiber posts, and to examine the effect on the resin cement thicknesses around the posts.

MATERIALS AND METHODS

Eighteen mandibular premolar roots were separated into two groups for oval and circular fiber posts systems. Post spaces were prepared and fiber posts were luted to the post spaces. Roots were cut horizontally to produce 1-mm-thick specimens. Resin cement thicknesses were determined with a metallographic optical microscope and push-out tests were done.

RESULTS

No significant differences were observed in terms of push-out bond strength between the oval and circular fiber posts (P>.05) The resin cement thicknesses of the oval posts were greater than those of the circular posts group in the coronal, middle and apical specimens (P<.05).

CONCLUSION

In the light of these results, it can be stated that resin cement thickness does not affect the push-out bond strength.