Type of the Paper (Article Journal of Baghdad College of Dentistry, Vol. 34, No. 3 (2022), ISSN (P): 1817-1869, ISSN (E): 2311-5270 7 Research Article The push out bond strength of bioceramic seal- er(Total Fill) after warm and cold obturation tech- niques An in vitro comparative Batool Basim Mounes 1*, Raghad Alhashimi2 1 Master Student, Department of conservative dentistry, College of Dentistry, University of Baghdad. 2 Professor, Department of conservative dentistry, College of Dentistry, University of Baghdad. *Correspondence: batoolbasim92@gmail.com Abstract: Background: The goal of a root canal treatment is three dimensional obturation with a complete seal of the root canal system. The aim of this study was to evaluate and compare the effect of two warm obturation techniques, warm vertical compaction (WVC) and, carrier based obturation technique Gutta Core (GC), versus two cold obturation tech- niques, cold lateral compaction (CLC) and, single cone (SC) on push-out bond strength of bioceramic sealer (Total Fill) at three different root levels. Materials and Methods: Forty ex- tracted maxillary first molars teeth with a straight round palatal root canal and mature apices were selected for this study. After sectioning the palatal roots to 11 mm from the root apex, the canals were prepared with EDGEENDO X7 rotary system file from size 20 up to size 40 taper 04. The samples were then randomly separated into four groups based on obturation procedures (each group n = 10), with group A: obturated by WVC, group B: GC, group C: CLC, and group D: SC. Following obturation, the teeth were kept in an incubator at 37°C and 100% humidity for two weeks. Three slices of 2 mm thickness were cut horizontally at 2, 4.5, and 7 mm from the root apex in each of the three sections (apical, middle and coronal). The data were investigated using one-way ANOVA and Tukey's test with a significance level (p< 0.05). A digital microscope with a magnification of 60 X was used to establish the failure mode. Results: There was a significant increase in push-out bond strength following canal obturation with GC and WVC, particularly at the apical third (9.48, and 8.11 MPa, respec- tively) , compared to canals obturated with SC and CLC in all root levels except the middle third, at the (p< 0.05) significance level. The cohesive mode of failure was the most prevalent in all groups. Conclusio: BC (TotalFill) sealer showed higher bond strength when used in WVC and GC compared to other techniques. SC and CLC were showed comparable bond strength values. Keywords: TotalFill BC, GuttaCore, Single cone, Push out test. Introduction Various obturation procedures have been used to fill the root canal system over the years, but none was perfect. According to Schilder, the optimal root canal obturating material must conform to the canal walls and irregularities (1). According to Grossman, who investigated the physical qualities of filling ma- terials, root canal sealers should have a high degree of adhesion(2). As Caicedo and von Fraunhofer re- ported, root canal sealants are essential for keeping the root canals from drying out(3). TotalFill® BC Sealer (FKG Dentaire SA, La-Chaux-de-fonds, Switzerland) is a pre-mixed calcium silicate bioceramic sealer that cures to generate hydroxyapatite, which attaches to the root canal dentine surface as well as the bioceramic-coated gutta-percha points. TotalFill® BC Point, is a recently introduced hydrophilic sealer, composed of zirconium oxide, cal- cium silicates, calcium phosphate monobasic, calcium hydroxide, and various filling and thickening agents (4). It is possible to employ Hydraulic condensation with a single cone approach because of its ze- ro shrinkage and mild expansion; improved sealing is produced by joining bond bioceramic-coated gut- ta-percha points to the bioceramic sealer by chemical bonding (5). Received date: 2-1-2022 Accepted date: 4-2-2022 Published date: 15-9-2022 Copyright: © 2022 by the authors. The article is published under the terms and conditions of the Crea- tive Commons Attribution (CC BY) license (https://creativecommons.org/licens es/by/4.0/). https://doi.org/10.26477/jbcd .v34i3.3212 https://creativecommons.org/licenses/by/4.0/ https://creativecommons.org/licenses/by/4.0/ https://doi.org/10.26477/jbcd.v34i3.3212 https://doi.org/10.26477/jbcd.v34i3.3212 J. Bagh. Coll. Dent. Vol. 34, No. 3. 2022 Mounes and Alhashimi 8 Because of the irregular shape of the root canal, a single cone may be unable to completely seal the opening (6). The warm vertical technique and other thermoplasticized obturation are widely used by en- dodontists because of their efficiency in filling canal irregularities. Because of the new calcium silicate– based sealers, many practitioners may favor a thermoplasticized method rather than the SC technique, despite the producers' advice. The impact of the thermoplasticized process on these sealers' sealing characteristics has yet to be assessed (7). The GuttaCore support is belongs to patented cross-linked gutta-percha and was created in 2010 (8). A carrier can combine the thermoplasticized GP and sealer horizontally and perpendicularly more quickly using this approach (9). The adhesion strength of the sealer and the appropriate technique used with it is important to achieve single adhesion unit (monoblock) and prevent any leakage. Because there were limited studies regarding the effect of obturation techniques on bond strength and adhesion capac- ity of bioceramic TotalFill sealer, therefore, the purpose of the current study was to evaluate and com- pare the effect of two warm obturation techniques, warm vertical compaction (WVC) and carrier-based obturation technique Gutta Core (GC) versus two cold obturation techniques, cold lateral compaction (CLC) and (SC) on the push-out bond strength of bioceramic sealer (TotalFill) at three different root lev- els. The null hypothesis was that there are no significant differences in the push-out bond strength of TotalFill bioceramic sealer after different obturation techniques. Materials and Methods For this study, forty extracted maxillary first molars with round and straight palatal root canals and mature apices were used. The palatal roots were split vertically to the root's long axis at the furca- tion area to take a flat reference point for measurement. Palatal roots were cut to achieve a standard length of 11 mm(10). Size 20 K-file was utilized to define the initial size of the canal, EDGEENDO X7 Ro- tary system files were used for instrumentation, starting with a size 20/04 rotary file, then 25/04, 30/04, 35/04, and 40/04 with a speed of 300 rpm and torque 300 g-cm till the working length (two–movement were used for each file) by gentle push in and out motion. Between each rotary file, recapitulation was done with a size #20 hand K-file to keep the glide path and help the lubricant to reach the canal terminus. During canal preparation, 1 ml of 2.5%, NaOCl irrigation was used between instruments using a 30-gauge needle (side vented) 2 mm short of the working length to remove debris. After instrumenta- tion, the canals were irrigated with 2 ml of 2.5% NaOCl(11). Finally, 1 ml of EDTA 17% was used for 1 min agitation using sonic endoactivator(Dentsply Maillefer, Switzerland) with irrigation tip size 25 followed by 3 ml of 2.5% NaOCl for 1 min agitation using sonic endoactivator. Final rinsing with 5 ml saline solu- tion(12). The samples were divided randomly into four groups based on the obturation methods (each group n = 10), group A: obturated by WVC, group B: GC, group C: CLC, group D: SC Group A: Warm vertical compaction The canals were obturated with a bioceramic coated 40/04 master cone. An intracanal tip was used to apply BC (TotalFill) sealer (FKG, Dentaire, Switzerland). The master cone was cut using a heated plugger (Fi-P, Woodpecker Medical Instrument Co., Guangxi, China)with a binding point of 4 mm short of the working length. It was just the apical portion of the gutta-percha that was maintained (4 mm). An injection of warm gutta-percha (Fi-G, Woodpecker Medical Instrument Co., Guangxi, China) set at 180°C J. Bagh. Coll. Dent. Vol. 34, No. 3. 2022 Mounes and Alhashimi 9 was used for the backfilling of the canal. A needle (40/04) was inserted into the root canal for 5 seconds and then the gutta-percha was extruded before.It could harden. Finally, a plugger was used to compact the gutta-percha at the orifice level. Each canal was treated with two GP pieces that had been heated to a high temperature (3 to 4 mm of GP). Group B: GuttaCore obturator The BC sealer was inserted into the coronal one-third of the canal system with an intracanal tip. Size 40 of the GuttaCore obturator was chosen and inserted into the Thermaprep 2 oven's obturator holder (Tulsa Dental Dentsply, Tulsa OK, USA). The temperature of the oven was set according to the size of the obturator and the holder was pushed down in order to start thermoplasticzing the obturater. After several seconds, the obturator was ready to be used. After removing the obturator from the oven, it in- serted into the working length of the canal with a downward pressing movement. It was necessary to bend the obturator's handle in both directions to remove extra material from the orifice. Group C: Cold lateral compaction Bioceramic coated GP 40/04 master cones, and TotalFill BC sealers (FKG, Dentaire, Switzerland) were used to seal the canals. An intracanal tip was inserted into the canals to insert the sealer in the coronal one-third (4 mm) of the canals. In the next step, a stainless-steel finger spreader size 25 (Dentsply Tulsa) was used to execute cold lateral-compaction, and tiny auxiliary gutta-percha cones (15 and 20) (Diadent, North FraserWay, Burnaby, BC, Canada)were introduced and condensed laterally to fill the canal space. Finally, the cones were cut down to the same level as the orifice(13). Group D: Single cone Bioceramic coated GP 40/04 cone and TotalFill BC sealer was used to obturate the canals, as sug- gested by the manufacturer. The intracanal tip of the BC sealer was inserted into the coronal one-third of the canal. The cone was cut off at the level of the orifice and lightly packed vertically with a plugger to create a tight seal. The samples were wrapped in gauze and kept in an incubator at 37°C and 100% humidity for two weeks to confirm that the sealer had adequately solidified.(13) After that, three slices of 2 mm thickness were horizontally sectioned using a water-cooled precision saw (Ernst-Leitz, Wetzlar, Germany) with a diamond disk (0.5mm) thickness from root apex to include all roots at points 2, 4.5 and 7 mm level(14,15). For each segment, the apical and coronal diameters of the canal were measured using the ImageJ soft- ware analysis program (National Institutes of Health, USA). A digital caliper was used to verify the thickness of the section. The apical aspect per slice was compressed using a cylindrical plunger (punch pin) installed on a universal testing Machine (Z wick Roell, Germany). The maximal force in Newton was measured at 0.5 mm/min in an apical-coronal direction until the initial dislodgement of obturating substance and a sharp decline along with the load deflection. Punch pins with diameters of 0.7 mm, 0.5 mm, and 0.4 mm were used, calculated as 90% of canal diameter in the apical side of each root slice, the coronal, middle, and J. Bagh. Coll. Dent. Vol. 34, No. 3. 2022 Mounes and Alhashimi 10 apical slices. Punch pins must almost entirely cover the central cone without touching the canal walls or sealer that was used (Fig. 1). The maximal force (F-max) where the filing materials were dislodged was registered, and the strength of push-out bond (MPa) was computed per sample using the formula: Strength of push-out bond (MPa) = F-max / area of adhesion surface (mm²) F-max: Maximal force. The formula used to calculate the surface adhesion value is presented below.: Area of adhesion surface = (D1 + D2/2) ×μ×h Where D1=apicaldiameter,D2=coronal diameter, μ = 3.14, and h = the section thickness Figure (1): Schematic illustrates the push-out testing. Evaluation mode of the failure Following the push-out test, the specimens were examined under a 60 X magnification digital micro- scope to determine the failure forms (cohesive, adhesive, and mixed) that happened due to the stopper being displaced from the samples. Failure was considered: - Adhesive after the sealer has been entirely removed from the dentine (dentine surface without sealer). - Cohesive if the sealer contained within it has become separated (dentine surface completely was cov- ered by sealer). - Mixed, implying that both adhesive and cohesive modes are present at the same time (dentine surface partially covered by the sealer). Statistical analysis: SPSS software for Windows (Version 25.0, IBM Corp., Armonk, NY, USA) was used for statistical analysis. The p<0.05 significance level was chosen. The study's primary outcome var- iable was bond strength in MPa. The information gathered was examined utilizing one way ANOVA test, followed by Tukey HSD comparison test. Failure mode was an additional outcome variable. Results Table 1 and Figure 2 display the mean and standard deviation of the bond strength (MPa) in groups. For the first technique (CLC ), the highest mean values were recorded in the apical part (4.453)MPa fol- lowed by the middle (4.181)MPa, then the coronal part (3.003)MPa with a highly significant difference, for SC the mean strength of push-out was more elevated in coronal (4.205)MPa followed by apical (3.617)MPa then middle part (3.242) MPa. J. Bagh. Coll. Dent. Vol. 34, No. 3. 2022 Mounes and Alhashimi 11 Regarding the other two obturation techniques, the situation was different, where the mean strength of push-out was higher in the apical part in (GC, WVC) (9.482, 8.119, respectively)MPa followed by the coronal (2.439)MPa, then the middle (2.191)MPa in GC technique and the middle (4.535)MPa, and finally the coronal in WVC (2.439)MPa technique again with highly significant difference (p<0.05). The differences in the strength of push-out bond at different root levels using different obturation techniques, according to one-way ANOVA test, are shown in in Table 1. In group CLC, a statically significant difference was found between (coronal), (middle), and (apical) groups,(p=0.014). The apical third recorded the highest mean value, then the middle and the coronal third. In group SC, a statically significant difference was found between (coronal), (middle), and (apical) groups, (p=0.016). The coronal third was recorded as the highest mean value followed by the (apical) third, then the (middle) third. In group WVC, a statically significant difference was found between coronal, middle, and apical, (p=0.000). The apical third was recorded as the highest mean value followed by (middle) third, then (coronal) third. In group GC, a statically significant difference was found between coronal,middle,and apical groups, (p=0.000). The apical third was recorded as the highest mean value followed by (coronal) third, then (middle) third. Table (1): Descriptive and inferential statistics for the difference in the strength of push-out bond at different root levels using different obturation techniques. S:significant, HS:high significant, NS:non significant The statistical analysis employed the following levels of significance: NS p>0.05, S 0.05 p<0.01 HS. techniques Levels Descriptive statistics Levels difference N Mean S.D. F-test p-value clc Apical 10 4.453 0.841 5.029 0.014 S Middle 10 4.181 1.410 Coronal 10 3.003 0.921 sc Apical 10 3.617 0.548 4.834 0.016 S Middle 10 3.242 0.726 Coronal 10 4.205 0.796 wvc Apical 10 8.119 1.136 67.401 0.000 HS Middle 10 4.535 1.301 Coronal 10 2.439 0.830 Gc Apical 10 9.482 1.239 99.426 0.000 HS Middle 10 2.191 0.800 Coronal 10 4.916 1.386 J. Bagh. Coll. Dent. Vol. 34, No. 3. 2022 Mounes and Alhashimi 12 0.000 2.000 4.000 6.000 8.000 10.000 12.000 clc sc wvc Gc clc sc wvc Gc clc sc wvc Gc Apical Middle Coronal m e a n ( M P a ) Figure (2): The average bond strength values ( in MPa). Regarding the effect of groups: in Table 2 A) Apical: There was a statistically high significant difference between CLC and each of WVC, GC (p<0.001). A statistically low significant difference was found between WVC and GC (p<0.05). There was no statisti- cal difference between CLC and SC (p=0.242). B) Middle: There was no statistically significant difference between CLC with SC, WVC and SC with WVC and GC (p>0.05). A statistically high significant difference was found between CLC and GC (p=0.001), and between WVC and GC (p=0.000). C) Coronal: There was no statistically significant difference between CLC with SC, WVC and between SC with GC (p>0.05). A statistically low significant difference was found between CLC with GC, SC with WVC, WVC with GC (p<0.05). Table (2): Multiple comparisons among different obturation techniques using Tukey's HSD test Levels Obturation techniques Mean Difference p-value Apical clc sc 0.836 0.242 NS wvc -3.666 0.000 HS Gc -5.029 0.000 HS sc wvc -4.502 0.000 HS Gc -5.865 0.000 HS wvc Gc -1.363 0.018 HS Middle clc sc 0.939 0.243 NS wvc -0.354 0.889 NS Gc 1.990 0.001 HS sc wvc -1.293 0.058 NS Gc 1.051 0.162 NS wvc Gc 2.344 0.000 HS Coronal clc sc -1.202 0.054 NS wvc 0.564 0.602 NS Gc -1.913 0.001 HS sc wvc 1.766 0.002 S Gc -0.711 0.407 NS wvc Gc -2.477 0.000 HS S:significant,HS: high significant, NS:non significant J. Bagh. Coll. Dent. Vol. 34, No. 3. 2022 Mounes and Alhashimi 13 Failure mode The highest failure mode was recorded as follows: CLC (cohesive), SC (cohesive), WVC (adhesive), and GC (cohesive) with no significant difference (Fig. 3). Figure (3): Mode of failure A : Adhesive (S\G), B: Adhesive (D\S), C: Mixed, D: Cohesive(G). Discussion Root canal fillings are used to keep oral bacteria and their products from seeping into the apical periodontium and prevent bacteria that remain in the root canal afterward cleaning and shaping from escaping to the periapex (16). Schilder conceived and described the thermoplastic root filling techniques, which are based on the vertical compaction of warm gutta-percha (17). The thermoplastic root filling techniques have been extensively studied and found to be beneficial in root canal system filling, filling material homogeneity, and apical seal (18) . In this study, BC sealer TotalFill+BC coated gutta-percha (To- talFill) was used to improve bonding by forming an actual gap-free seal single cohesive unit (monoblock) as claimed by Trope et al., 2015(5). But the result demonstrates a reduction in bond strength in single cone and CLC compared to WVC and GC, so the finding in this study disagrees with this monoblock idea. SEM analysis was used to determine the adaptation of BC sealer to BC coated points and revealed an interfacial space between the BC sealer and the coated GP The chemical connection between the BC sealer and the coated gutta-percha point was investigated (19) .Additional research utilizing various ana- lytic tests is necessary to determine the degree of adhesion between the sealer and the coated point, as well as whether or not, it affects the quality of the root canal obturation. In this study, CLC and SC have comparable bond strength mean values with no difference regarding the effect of root levels. This may back up the manufacturer's advice for TotalFill BC, which recommends using TotalFill BC sealer with a single hydraulic technique. According to the findings of this study, the highest mean values were ob- tained when the thermoplasticized gutta-percha obturation technique (WVC, GC) in all root levels ex- cept GC in the middle third which showed low bond value. These findings could be attributed to an increasing flow of warm gutta-percha, (20) resulting in a well-mixed bulk of gutta-percha and a small amount of sealer. This is frequently associated with an in- crease in material retention (17). Several investigations also showed that the softening gutta-percha in thermoplasticized procedures had the flexibility to flow into deep depressions, lateral canals, auxiliary canals, and imperfections not filled by sealer cement (11). The thermoplasticized procedures produce more gutta-percha, less sealer, and fewer empty gaps than SC and CLC. Because most endodontic seal- ers are soluble and shrink slightly, it is better to rely on gutta percha material percentage in the apical C D A B J. Bagh. Coll. Dent. Vol. 34, No. 3. 2022 Mounes and Alhashimi 14 section as little as possible (13). The result of this study disagrees with (Putrianti et al., 2020) study that found CLC provides better adhesion ability than WVC (21). When there was no statistical significance difference among the tested levels regardless of the obturation materials used, this is in agreement with the results of (Costa et al., 2010) who demonstrated that fluctuations in tubular density along the canal are inadequate to cause sealer adhesion to be affected (22). The most predominant mode of failure is cohe- sive failure mostly (gutta-percha) in TotalFill BC except in WVC (adhesive) could be attributed to a thin layer of sealer incorporated in the dentinal tubules with some expansion due to the hydrophilic na- ture of the BC calcium silicate-based sealers have good adhesion to the root canal. WVC, GC reported high bond strength in TotalFill BC with a highly significant difference especially apical third in GC. This could be explained by a very limited widening of the canal in the apical part, making it impossible to perform push-out tests without values having a frictional component with the canal walls (23). The adhe- sive mode of failure in WVC could be attributed to the sealer not being compacted against the root canal wall. Guttacore's predominant failure mode was cohesive; this could be because the thermoplastic Gut- ta-percha pierced the dentinal tubules, resulting in well-adapted root obturation, or it could be due to the composition of GuttaCore, which is composed of two layers of Gutta-percha: an inner cross-linked layer and a flowable outer layer(24). Conclusion The bond strength of TotalFill BC sealer had a considerable influence on the obturation methods used in this study. To provide a high bond strength value,TotalFill BC can be used with warm obtura- tion procedures (GuttaCore, warm vertical technique). Conflict of interest: None. References 1. Schilder H. Filling root canals in three dimensions. Dent Clin North Am 1967:723-44. 2. Grossman LI. Physical properties of root canal cements. J Endod 1976;2(6):166-75. 3. Caicedo R, Von Fraunhofer JJJoE. The properties of endodontic sealer cements. J Endod 1988;14(11):527-34. 4. Debelian G, Trope MJGide. The use of premixed bioceramic materials in endodontics. G i d e 2016;30(2):70-80. 5. Trope M, Bunes A, Debelian GJET. Root filling materials and techniques: bioceramics a new hope? Endod Topics 2015;32(1):86-96. 6. Celikten B, Uzuntas CF, Orhan AI, Orhan K, Tufenkci P, Kursun S, et al. Evaluation of root canal sealer filling quality using a single‐cone technique in oval shaped canals: An In vitro Micro‐CT study. Scaning 2016;38(2):133-40. 7. DeLong C, He J, Woodmansey KFJJoe. The effect of obturation technique on the push-out bond strength of calcium silicate sealers. J Endod 2015;41(3):385-8. 8. Schroeder A, Ford N, Coil JJIej. Micro‐computed tomography analysis of post space preparation in root canals filled with carrier‐based thermoplasticized gutta‐percha. Int Endod J 2017;50(3):293- 302. J. Bagh. Coll. Dent. Vol. 34, No. 3. 2022 Mounes and Alhashimi 15 9. Hale R, Gatti R, Glickman GN, Opperman LAJIJoD. Comparative analysis of carrier-based obtura- tion and lateral compaction: a retrospective clinical outcomes study. Int J Dent 2012;8:954675. 10. AlHashimi M .An evaluation of coronal microleakage in endodontically treated teeth using two different obturation techniques and two types of sealer at four different time periods. A master the- sis, university of Baghdad, 2005. 11. Marciano M, Ordinola‐Zapata R, Cunha T, Duarte M, Cavenago B, Garcia R, et al. Analysis of four gutta‐percha techniques used to fill mesial root canals of mandibular molars. Int Endod J 2011;44(4):321-9. 12. Crumpton BJ, Goodell GG, McClanahan SBJJoe. Effects on smear layer and debris removal with varying volumes of 17% REDTA after rotary instrumentation. J Endod 2005;31(7):536-8. 13. Al-Hiyasat AS, Alfirjani SAJJoD. The effect of obturation techniques on the push-out bond strength of a premixed bioceramic root canal sealer. J Dent 2019;89:103169. 14. Ehsani S, Bolhari B, Etemadi A, Ghorbanzadeh A, Sabet Y, Nosrat AJP, et al. The effect of Er, Cr: YSGG laser irradiation on the push-out bond strength of realseal self-etch sealer. Photomed Laser Surg 2013;31(12):578-85. 15. Elmuttalibi HF, Mahdi JAJJoO, Research D. Push Out Bond Strength of GuttaFlow 2, Thermafil and Guttacore (An Invitro Study). J Oral Dent Res 2019;6(1). 16. Saunders W, Saunders EJDT. Coronal leakage as a cause of failure in root‐canal therapy: a review. Dent Traumtol1994;10(3):105-8. 17. Schilder HJJoe. Filling root canals in three dimensions. J Endod 2006;32(4):281-90. 18. Ungor M, Onay E, Orucoglu HJIej. Push‐out bond strengths: the Epiphany–Resilon endodontic obturation system compared with different pairings of Epiphany, Resilon, AH Plus and gutta‐ percha. Int Endod J 2006;39(8):643-7. 19. Eltair M, Pitchika V, Hickel R, Kühnisch J, Diegritz CJCoi. Evaluation of the interface between gut- ta-percha and two types of sealers using scanning electron microscopy (SEM). Clin Oral Investig 2018;22(4):1631-9. 20. Venturi MJIej. Evaluation of canal filling after using two warm vertical gutta‐percha compaction techniques in vivo: a preliminary study. Int Endod J 2006;39(7):538-46. 21. Putrianti A, Usman M, Nazar K, Meidyawati R, Suprastiwi E, Mahardhini SJIJoAP. Effects of cold lateral versus warm vertical compaction obturation on the push-out bond strength of bioroot™, a calcium silicate-based sealer. Int J Appl Pharm 2020:77-9. 22. Costa J, Rached‐Júnior F, Souza‐Gabriel A, Silva‐Sousa Y, Sousa‐Neto MJIej. Push‐out strength of methacrylate resin‐based sealers to root canal walls. Int Endod J 2010;43(8):698-706. 23. Babb BR, Loushine RJ, Bryan TE, Ames JM, Causey MS, Kim J, et al. Bonding of self-adhesive (self- etching) root canal sealers to radicular dentin. J Endod 2009;35(4):578-82 24. 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Vol. 34, No. 3. 2022 Mounes and Alhashimi 16 قوة رابطة الدفع للخارج للسداد الخزفي الحيوي )الملء الكلي( بعد تقنيات السد الدافئ والبارد دراسة مقارنة في المختبر بتول باسم مؤنس، رغد الهاشمي المستخلص: ( القائم على الناقل ، مقابل تقنيتي السد GC) Gutta Core( و WVCكان الهدف األساسي لهذه الدراسة هو تقييم ومقارنة تأثير تقنيتي السد الدافئ ، الضغط العمودي الدافئ ) بناًء على قوة رابطة دفع مانع التسرب الخزفي الحيوي عند ثالثة مستويات جذر مختلفة.( ، SC( و ، مخروط مفرد )CLCالبارد ، الضغط الجانبي البارد ) ملم من 11تقسيم جذور الحنك إلى المواد والطرق: تم اختيار لهذه الدراسة أربعين ضرسًا مستخرًجا من الفك العلوي مع قناة جذر حنكي مستديرة مستقيمة بنهاية ناضجة. بعد .04تفتق 40حتى 20من EDGEENDO X7 Rotary Systemمم من قمة الجذر ، تم تحضير القنوات باستخدام ملفات 11. بعد تقسيم الجذور الحنكية إلى قمة الجذر ، B: GCلمجموعة ، ا WVC( ، مع المجموعة أ: مسد بواسطة 10ثم تم فصل العينات بشكل عشوائي إلى أربع مجموعات بناًء على إجراءات السد )كل مجموعة ن = تم قطع ثالث شرائح بسمك ٪ لمدة أسبوعين. 100درجة مئوية ورطوبة 37. بعد االنسداد ، تم االحتفاظ باألسنان في حاضنة عند D: SC، والمجموعة C: CLCالمجموعة أحادي االتجاه واختبار ANOVAتحليل البيانات باستخدام اختبار تم مم من قمة الجذر في كل قسم من األقسام الثالثة )قمي ، وسط ، إكليلي(. 2،4.5،7مم أفقياً عند 2 Tukey ( بمستوى معنويةP <0.05 تم استخدام مجهر رقمي مع تكبير .)60 X .لتحديد وضع الفشل ال سيما عند الثلث القمعي ) WVCو GCكانت هناك زيادة كبيرة في قوة رابطة الدفع بعد انسداد القناة باستخدام النتائج: ( ميجا باسكال ، مقارنة بالقنوات 9.48,8.11، ( مستوى معنوية. كان النمط المتماسك للفشل هو األكثر انتشاًرا في جميع الفئات. P< 0.05في جميع مستويات الجذر باستثناء الثلث األوسط ، ) CLCو SCالمسدودة بـ قابلة للمقارنة. CLCو SC. كانت قيم قوة الرابطة لـ GCو WVC)الملء الكلي( قوة رابطة فائقة في BCى ، يُظهر مانع التسرب االستنتاجات: مقارنة بالتقنيات األخر