The Effect of Different Drying Protocols on the Bond Strength of AH Plus Sealer Using Vertical Condensation Technique. (A Comparative in Vitro Study)

The Effect of Different Drying Protocols on the Bond Strength of AH Plus Sealer Using Vertical Condensation Technique. 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(A Comparative in Vitro Study) Amira Arar, Helen Rushdi Ayoubi, Alaa Alhomsi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8450719/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objectives The purpose of this in vitro study was to evaluate the effects of isopropanol alcohol, ethanol alcohol when used for final irrigation and the paper points as drying protocols, on the bond strength of AH Plus sealer using the warm vertical condensation technique. Materials and Methods Thirty single-rooted human permanent teeth were decoronated to a length of 15 mm. The roots were randomly divided into three groups (n = 10 for each group) according to the drying protocol: (G1: Paper points, G2: 70% Isopropanol, and G3: 95%Ethanol). Thirty roots were prepared by using Pro Taper universal rotary instruments. G1: the canals were blot dried with paper points until the last one appeared dry, G2: the canals were dried with paper points followed by dehydration with 70% isopropanol, and G3: the canals were dried with paper points followed by dehydration with 95% ethanol. After drying, the canals were obturated with AH Plus sealer and gutta-percha (AH/GP) using the vertical condensation technique. Then, each root was sectioned into three slices with 2-mm-thick (coronal, middle, apical thirds) using a diamond disc. The push-out strength was tested for each slice between the sealer and dentin wall using a universal testing machine at a crosshead speed of 1 mm/min, and failure modes were examined under a stereomicroscope at a (40X) magnification. The data were statistically analysed using a One-way ANOVA test, this was followed by a pair-wise comparison using the Bonferroni test, and all data were analysed at a 95% confidence interval (P-value ≤ 0.05). Results Results showed that there were statistically significant differences for the studied three groups (P < 0.05), where G2 exhibited significantly higher bond strength values compared to G3 (P < 0.05), while the lowest push-out strength was observed in G1. For the failure modes, there were statistically significant differences in the failure mode between the three groups (P < 0.05). For different levels of root, there were statistically significant differences (P < 0.05): the majority were cohesive failures 80%) in the coronal thirds of G2 and G3, while in G1, mixed failure was common, followed by adhesive failure to a lesser extent. Conclusions Within the limitations of this in vitro study, drying with (70% Isopropanol, 95% Ethanol) enhanced the bond strength between AH Plus sealer and dentinal tubules more effectively than the conventional paper point drying method when using the warm vertical condensation technique, with 70% isopropanol superior to the rest of the studied groups. Health sciences/Health care Health sciences/Medical research 70% Isopropanol 95% Ethanol Paper Points AH Plus Sealer Vertical Condensation Figures Figure 1 Figure 2 1-Introduction 1-Introduction : Successful endodontic therapy relies on a sequence of interdependent procedures designed to eliminate infection, prevent reinfection, and preserve the function of the treated tooth 1 . The quality of root canal obturation has been identified as a critical determinant of endodontic treatment success. 2 The complex anatomy of the endodontic system, characterized by irregularities, fins, isthmuses, and lateral canals, makes the three-dimensional obturation complicated. 3 This anatomical complexity underscores the essential role of three in achieving long-term clinical success, which aims to fill the entire root canal system, including its accessory and irregular components 4 . Modern obturation materials, such as gutta-percha in combination with advanced sealers, were engineered to adapt closely to canal walls and penetrate microscopic irregularities, enhancing the quality of the seal. 5 In endodontic research, epoxy resin–based sealers, such as AH Plus (Dentsply, Germany), are frequently used as a control material because of their reduced solubility, long-term dimensional stability, sealing capacity, radiopacity, and adequate micro retention to dentin 6 . Advancements in obturation techniques, such as warm vertical compaction, have significantly improved the clinician’s ability to achieve a dense, homogeneous fill and enhance the flow of obturation materials into lateral canals and complex anatomical spaces that would otherwise remain unfilled using traditional cold lateral compaction. Numerous studies have demonstrated that three-dimensional obturation reduces microleakage and improves the long-term prognosis of endodontically treated teeth 7 . In this regard, the presence of moisture within the root canal system, including the dentinal tubules, can occupy space and hinder the penetration of filling materials. 8 Although paper points are the most commonly used method for canal drying in clinical practice, the moisture may persist in irregular canal regions and lateral canals even after their use 8 . Moisture can interfere with the setting of root canal sealers by altering their working and setting times. It may also hinder sealer penetration and reduce bond strength to dentin 9 . Since no standardized protocol exists to achieve the ideal residual moisture, several chemicals, including alcohol, have been evaluated for their potential to improve dentinal wettability 8 . Ethanol and isopropanol are widely used adjuncts in endodontic practice due to their strong ability to displace residual moisture from dentinal surfaces. Ethanol, particularly at high concentrations such as 95%, isopropanol, commonly used at 70%. This process reduces surface tension, increases dentinal surface energy, and lowers the contact angle, thereby improving dentinal wettability and facilitating better sealer penetration and adhesion 10 . Although laboratory studies have investigated the effect of Despite the availability of laboratory studies evaluating the effect of ethanol 11 , isopropanol 12 , or paper point drying on dentin adhesion and AH Plus performance, no investigation has simultaneously compared these protocols or integrated them with warm vertical compaction technique using AH Plus. This gap highlights the need for comprehensive studies addressing the combined impact of different drying methods within clinically relevant obturation protocols. Therefore, this study aimed to evaluate and compare the push-out bond strength and failure modes of the epoxy-based sealer AH Plus, used in warm vertical compaction, after three distinct canal drying protocols: paper points, 70% isopropanol alcohol and 95% ethanol alcohol. 2- Materials and Methods Ethical approval : This study was conducted in accordance with the ethical approval from the Local Ethics Committee of Damascus University (No. 3227). It followed the CRIS Guidelines (Checklist for Reporting In-Vitro Studies). Study design and teeth selection: An experimental study was performed at the Faculty of Dental Medicine, Damascus University, at the Department of Endodontics and Operative Dentistry, from June 2024 to August 2025. Thirty single-rooted and single-canaled human permanent teeth were used. G*Power 3.1 software was used to calculate the sample size, based on a study by Jia-Sha Wang et al, that employed a similar methodology 13 . The power was estimated to be 90%, the probability of Type 1 error or α as 0.05, with an effect size (f) = 0.53, resulting in a total sample size of 30 teeth. The teeth were freshly extracted due to caries or periodontal disease, and they were taken from the department of oral and maxillofacial surgery in faculty of dental medicine-Damascus university, after obtaining informed consent from the patients to include the extracted teeth in the study, this is within the approval obtained from the university to conduct the research. No tooth extraction in particular was performed to use in this study. The soft tissue residue on the extracted teeth was removed, and then the teeth were stored in water at 4°C and used within one month after extraction 14 . Only premolars classified as type 1 according to Vertucci classification were included in the study 15 . Teeth with an open apex, resorption, or curved canals, and the tooth that was previously endodontically treated were excluded. Additionally, mesio-distal digital dental radiographies were used to evaluate the root canal anatomies of all the teeth, and the dentine thickness to exclude any teeth with less than 1mm dentine thickness. Then they were all examined under a stereomicroscope (Meiji Techno, Saitama, Japan) at a 20X magnification to exclude previously cracked and fractured teeth. Procedure: First, the specimens were decoronated by transversely sectioning the roots at 15 mm, with a double-faced diamond disc (Hager & Meisinger GmbH, Neuss, Germany) at a low-speed straight handpiece with an air/water spray coolant (Being, Foshan, China). Patency was confirmed with a #10 K-file (MANI, Japan), and the root canals were enlarged using Pro Taper Universal rotary instruments (Dentsply, Germany) according to the appropriate taper of each canal, then we reached the working length (1 mm from the apical foramen). The root canals were irrigated by using 2 mL of 5.25% sodium hypochlorite between each instrument. After preparation, the canals were irrigated with 2 mL of 17% EDTA (PH = 7.7) for 1 minute, followed by a final 5mL rinse with distilled water. Then, the appropriate master gutta-percha (GP) cones (Meta Biome, South Korea) were selected for each canal by ensuring that the cone reached the full working length with slight resistance upon withdrawal (Tug-Back). The 30 roots were randomly divided into three experimental groups (n = 10) for each group according to the drying protocol. Group (1): The canals were blot dried using paper points (Meta Biome, South Korea) until complete dryness of the last point was confirmed visually 13 . Group (2): After the removal of excess distilled water with paper points until complete dryness of the last point was confirmed visually, the canals were filled with 10 mL 70% isopropanol (OQEMA GmbH, Mönchengladbach, Germany) using a syringe with a side-vented needle carried to the WL. After being left in the canal for 10 seconds, the isopropanol was removed with paper points 13 . Group (3): After the removal of excess distilled water with paper points until complete dryness of the last point was confirmed visually, the canals were filled with 10 mL 95% ethanol (Chem-Lab NV, now AnalytiChem Belgium NV, Belgium) using a syringe with a side-vented needle carried to the WL. After being left in the canal for 10 seconds, the ethanol was removed with paper points 13 . The samples were filled using a GP cone and AH plus sealer (Dentsply, Germany) following the manufacturer’s instructions, using the vertical condensation technique. Warm vertical compaction was performed using a Fast Fill device (Eighteeth, Changzhou, China) set at 200 °C. The fastback tip was pre-fitted to a depth 4–5 mm short of the working length (WL). Following placement of AH Plus, 0.5 mm of the master cone was clipped to prevent extrusion of thermoplasticized gutta-percha beyond the apex. The cone was then inserted, and the fastback tip advanced in a single motion to the predetermined depth. After cooling for 15 s, a one‑second heat burst was applied before withdrawing the tip. This procedure was repeated twice: first at the middle third and then at the coronal third of the canal. Excess gutta-percha at the canal orifice was removed and compacted using a 0.6 mm (No. ½) hand plugger (Dentsply, Tulsa, OK, USA). Afterward, the canal orifice was restored using a temporary filling (Ghimas, Bologna, Italy) Then all samples were stored in an incubator (Binder, Tuttlingen, Germany) at 37ºC and 100% humidity for 7 days to allow the complete setting of the sealers 13 . Push - out strength test: Three slices with 2-mm-thick (slice in the apical third, slice in the middle third, and slice in the coronal third) were cut at intervals of 3, 5, and 9 mm from the apical to coronal third (30 slices each group) with a low-speed fan empty diamond disc with a thickness of 0.25 mm at a slow rotational speed of 25,000 cycles per minute under heavy water cooling at three levels (Hager & Meisinger GmbH, Neuss, Germany). The push-out test was performed using a Universal Testing Machine (Testometric Co. Ltd., Rochdale, UK), a crosshead speed of 1 mm/ min. Shafts with tip diameters of 0.4 mm, 0.8 mm, and 1.0 mm were used for the apical, middle, and coronal sections receptively 16 (Fig 1) . The push-out strength at failure was calculated in megapascals (MPa) by dividing the load in newtons (N) by the area of the bond interface: 13 Bond area: π(R+r) h where π = 3.14 R: The radius of the canal close to the crown. r: The radius of the canal close to the apex. Both measurements were calculated using AutoCAD software. h: The height of the slice in millimetres, which was standardized at 2 mm for all samples. Analysis of failure modes: The failure modes were observed under a stereomicroscope at a 40× magnification. Failures were classified as follows (Fig 2) : Adhesive failure: Failure occurred between the sealer and the inner wall of the root canal. Cohesive failure: Failure occurred inside the sealer. Mixed failure: The above failure modes both occurred. Statistical analysis: Statistical analysis was conducted utilizing IBM SPSS software version 24 (IBM SPSS Statistics® version 24, IBM Corp., New York, USA).Descriptive statistics were obtained for the measured forces (N) and expressed as stress values in megapascals (MPa). Data were first analysed with a One-way ANOVA test to determine if there were significant differences between Groups in the studied sample, and then the Bonferroni test was applied to make pair-wise comparisons. Data were analysed at a 95% confidence interval (P-value < 0.05). 3-Results Push-out strength: There was a significant difference in push-out strength between the 3 moisture condition groups (P < 0.05). The push-out bond strength values varied significantly across the different drying protocols and root canal sections (coronal, middle, and apical). Specimens dried with 70% isopropanol exhibited the highest bond strength values in all thirds, with Mean ± Standard Deviation (SD) values of (5.96 ± 0.53 MPa, 5.45 ± 0.31 MPa, and 4.74 ± 0.32 MPa) in the coronal, middle, and apical third respectively. 95% Ethanol also enhanced bond strength compared to paper point drying, yielding (5.14 ± 0.31 MPa, 4.45 ± 0.42 MPa, and 3.83 ± 0.36 MPa) in the coronal, middle, and apical thirds, respectively. In contrast, the paper point protocol resulted in the lowest bond strength values across all thirds (3.65 ± 0.19 MPa, 3.10 ± 0.30 MPa, and 2.61 ± 0.49 MPa), respectively. A consistent trend of decreasing bond strength from coronal to apical thirds was observed within each protocol (Table 1) . Failure mode Cohesive failure was the predominant mode across all root thirds, particularly in specimens dried with 70% isopropanol and 95% ethanol. In the coronal third, cohesive failures accounted for 80% of samples in both alcohol-based protocols, compared to 60% with paper point drying. Mixed failures were more frequent with paper point (30%) than with isopropanol or ethanol (20%). Adhesive failures were only observed in the coronal third with paper point drying (10%). In the middle third, cohesive failures ranged from 60% to 70%, with ethanol showing the highest proportion of mixed failures (40%). No adhesive failures were detected in this third under any protocol. In the apical third, paper point drying resulted in the lowest cohesive failure rate (20%) and the highest mixed failure rate (60%), along with 20% adhesive failures. In contrast, isopropanol and ethanol protocols yielded higher cohesive failure rates (70% and 60%) respectively, and no adhesive failures (Table2) . 4- Discussion The growing interest in adhesive endodontics has driven the development of various resin-based root canal sealers. Although many of these sealers exhibit suboptimal bond strength to dentin, achieving reliable adhesion remains essential for preserving the integrity of the sealer–dentin interface under mechanical stresses induced by tooth flexure, clinical procedures, or subsequent post space preparation 17 . Sealers are fundamental in the obturation process, as they significantly affect the overall quality of root canal treatment. Achieving strong adhesion between the sealer and the dentin wall is highly desirable, since it ensures the long-term stability and integrity of the sealer–dentin interface 18 . AH Plus is considered the gold‑standard epoxy resin–based sealer due to its long‑term dimensional stability, low solubility, and reliable interaction with dentin 19 . When used with vertical compaction, its sealing ability is further enhanced as the thermoplasticized gutta‑percha adapts closely to canal irregularities and distributes the sealer into accessory canals and dentinal tubules. The combination of heat‑softened gutta‑percha and the sealer’s minimal shrinkage results in a more homogeneous three‑dimensional fill and a durable apical seal, reinforcing its role as a reference material for evaluating newer sealers 19 . Push-out strength is commonly employed as an indicator of the adhesion between obturation materials and root canal walls due to its methodological simplicity and reproducibility 20 . This parameter reflects a composite measure encompassing the frictional resistance at the material–dentin interface, intermolecular bonding forces, and chemical adhesion to root dentin 21 . Additionally, push-out strength is influenced by factors such as frictional forces 22 , Polymerization shrinkage factor (C-factor) 23,24 ,and different root canal treatment protocols 25 . It is suggested that the push-out test offers a more accurate evaluation of adhesive strength than the traditional shear test 26 . This is primarily because the push-out test induces fracture parallel to the dentin–sealer interface, thereby representing a true shear stress condition in specimens with parallel-sided geometry 26 . In this study, the drying protocols exerted distinct influences on the push-out bond strength and the penetration of resin-based sealer into dentinal tubules. Canals dried with 70% isopropanol or 95% ethanol exhibited significantly greater bond strength compared to those dried with paper points. Conversely, canals dried with 70% isopropanol showed the highest bond strength overall. Paper points rely on the principle of direct contact and capillary action to absorb and adsorb water. However, due to the complex anatomy of the root canal system, some residual moisture may remain, forming a non-displaceable physical barrier that can hinder the complete penetration of endodontic 27 . However, Nagas et al, found that moisture remained in the irregular regions of the canal and in lateral canals after drying with paper points. This residual moisture may hinder complete sealer penetration and compromise the bond strength to dentin. Such findings highlight the limitations of paper point drying alone 8 . Several factors may explain why isopropanol provides stronger sealer–dentin adhesion compared to ethanol; Considering the hydrophilic propensity of the resin-based sealers, it may be speculated that isopropyl alcohol (C 3 H 7 OH), which has lower polarity than ethanol (C 2 H 5 OH), promoted less removal of the water from dentinal tubules, enhancing the dentin wettability, increasing the degree of conversion of the sealers 28 , Ethanol at high concentrations can excessively dehydrate the collagen network within dentin, leading to partial collapse of its structure 10 . Unlike ethanol, isopropanol leaves a small amount of residual moisture within the dentin collagen matrix, helping preserve its structural flexibility and allowing improved sealer penetration 12 . Moreover, resin-based sealers often require a slightly moist environment to optimize polymerization. Isopropanol provides this balanced condition, whereas ethanol may leave an overly dry surface that reduces the degree of conversion. Additionally, due to its viscosity and physical properties, isopropanol may facilitate deeper penetration into dentinal tubules compared to ethanol, thereby enhancing mechanical contact between the sealer and dentin 29 . Ethanol evaporates rapidly, causing excessive dehydration and collagen shrinkage, whereas isopropanol’s slower evaporation maintains a more stable dentinal surface for sealer adhesion 29 . The differences in push-out bond strength among the coronal, middle, and apical thirds can be explained by several factors. The coronal third generally exhibits the highest values due to greater dentinal tubule density 30 ,more effective irrigant penetration 31 ,and easier smear layer removal 32 . In addition, condensation of the sealer and gutta-percha is more efficient in this region because of the wider canal diameter and better accessibility 33 . The middle third showed moderate bond strength, reflecting a gradual decrease in tubule density and slightly reduced efficiency of condensation, although irrigants and sealers can still penetrate adequately. Conversely, the apical third demonstrates the lowest bond strength, which may be attributed to reduce tubule density, complex apical anatomy, limited irrigant penetration, residual smear layer, and less effective condensation due to restricted access and narrow canal dimensions 12 . Furthermore, Instrumentation pressure during mechanical preparation may induce subtle alterations in the canal walls, with a more pronounced effect in the coronal and middle thirds compared to the apical third. 34 These changes influence the surface characteristics available for bonding and may partly explain the higher bond strength observed coronally and in the middle segment. In addition, sealer distribution tends to be more uniform in the coronal and middle thirds, whereas in the apical third, the narrower canal diameter and complex anatomy often lead to uneven accumulation of the sealer 34 .Together, these factors contribute to the differences in push‑out bond strength among the three canal regions. Canals dried with 70% isopropanol or 95% ethanol alcohol showed no adhesive failure along the sealer and inner wall of the root canal, a result that may be partly attributed to the bonding forces established between the sealer and the dentinal surface. In contrast, adhesive failure was observed when canals were dried using paper points alone, highlighting the influence of the drying protocol on the integrity of the sealer–dentin interface 8 . While canals dried with 70% isopropanol, Ethanol 95% a relatively high cohesive failure mode was observed, which may suggest that alcohol allows for a stronger interaction with the canal dentin wall. Mixed failure was observed in 60% of the apical third specimens in the paper‑points group, whereas 20% exhibited adhesive failure. This pattern may be partly explained by the complex apical anatomy, including the presence of secondary canals, which can hinder sealer solidification and limit its interaction with the canal walls 13 . Notably, the incidence of mixed failure decreased to 40% in the apical third when canals were dried using ethanol, and further declined to 30% when isopropanol was applied. Under these drying conditions, cohesive failure became more predominant, suggesting improved sealer adaptation and stronger interaction with the dentinal walls 35 . To validate and extend these findings beyond the in‑vitro setting, future clinical trials that closely replicate the current experimental design are strongly recommended. Such investigations would enable the translation of laboratory outcomes into clinical practice, thereby substantiating the clinical relevance of isopropanol drying as a final step in root canal preparation and confirming its potential to enhance the long‑term success of obturation. 5- Conclusion Within the limitations of this in vitro study, drying the canals with 70% isopropyl alcohol yielded the highest bond strength between AH Plus sealer and dentinal tubules when using the warm vertical condensation technique. Although 95% ethanol also improved bonding, its effect remained inferior to 70% isopropanol alcohol, while the paper‑points method consistently produced the lowest values. These findings highlight the clear superiority of alcohol‑based drying protocols over conventional drying approaches. Declarations Authors' contributions: Amira Arar, contributed to drafting, reviewing and editing. The author read and approved the final manuscript. Helen Rushdi Ayoubi, the supervisor, contributed to mentoring, reviewing and editing. The author read and approved the final manuscript. Alaa Alhomsi * , contributed to drafting, reviewing and editing, corresponding. The author read and approved the final manuscript. Data availability statement: All data generated or analysed during this study are included in this published article. Funding Information: The authors have no sources of funding. Conflict Of Interest: The authors declare that they have no competing interests. Ethics Approval Statement: The study protocol received approval from the Damascus University Ethics Committee (Date 2023/No. 3227). Consent: consent approval was received from the patients before teeth extraction, to be used in laboratory research. References Foschi, F. in Common Complications in Endodontics: Prevention and Management 183–207 (Springer, 2025). Ørstavik, D., Qvist, V. & Stoltze, K. J. E. j. o. o. s. A multivariate analysis of the outcome of endodontic treatment. 112, 224–230 (2004). Dzankovic, A., Korac, S. & Tahmiscija, I. Endodontic Challenges Arising from Root Canal Morphology. (2024). Versiani, M., Martins, J. & Ordinola-Zapata, R. J. A. d. j. Anatomical complexities affecting root canal preparation: a narrative review. 68 , S5–S23 (2023). Zhou, H. et al. Physical properties of 5 root canal sealers. 39 , 1281–1286 (2013). Carneiro, S. et al. Push-out strength of root fillings with or without thermomechanical compaction. 45 , 821–828 (2012). Aminsobhani, M. et al. Coronal microleakage in root canals obturated with lateral compaction, warm vertical compaction and guttaflow system. 5 , 83 (2010). Nagas, E. et al. Dentin moisture conditions affect the adhesion of root canal sealers. 38 , 240–244 (2012). Ehsani, M., Dehghani, A., Abesi, F., Khafri, S. & Dehkordi, S. G. J. J. o. d. r., dental clinics, dental prospects. Evaluation of apical micro-leakage of different endodontic sealers in the presence and absence of moisture. 8, 125 (2014). Grégoire, G., Sharrock, P. & Tavernier, B. J. O. H. & Care. Dentinal variations after application of an adhesive containing isopropanol used in etch and rinse mode on moist and dried dentin. 4 , 1–5 (2019). Ayar, M. K. J. E. j. o. d. A review of ethanol wet-bonding: Principles and techniques. 10, 155–159 (2016). Pantoja, C. A. et al. Influence of ethanol on dentin roughness, surface free energy, and interaction between AH Plus and root dentin. 32 , e33 (2018). Dias, K. C. et al. Influence of drying protocol with isopropyl alcohol on the bond strength of resin-based sealers to the root dentin. 40 , 1454–1458 (2014). Wang, J. S., Bai, W., Wang, Y. & Liang, Y. H. J. J. o. D. S. Effect of different dentin moisture on the push-out strength of bioceramic root canal sealer. 18 , 129–134 (2023). Mobarak, E. H., El-Badrawy, W., Pashley, D. H. & Jamjoom, H. J. T. J. o. p. d. Effect of pretest storage conditions of extracted teeth on their dentin bond strengths. 104 , 92–97 (2010). Vertucci, F. J. J. O. s., oral medicine, oral pathology. Root canal Anat. Hum. permanent teeth . 58 , 589–599 (1984). Frasquetti, K. S. et al. Effect of different root canal drying protocols on the bond strength of two bioceramic sealers. 17 , 1229–1234 (2023). Almutairi, N. M. et al. Sealing ability and micro leakage of AH26 and AH plus root canal sealers: A systematic review. 14 , 140–146 (2023). Attash, I. & Wiaam, A. A. J. A.-R. D. J. Push-out Bond Strength Evaluation for Different Endodontic Sealers (A Comparative Study). 22 , 301–312 (2022). Álvarez Vásquez, J. L. Epoxy resin-based root canal sealers: an integrative literature review. (2024). Razmi, H., Bolhari, B., Dashti, N. K. & Fazlyab, M. J. I. e. j. The effect of canal dryness on bond strength of bioceramic and epoxy-resin sealers after irrigation with sodium hypochlorite or chlorhexidine. 11 , 129 (2016). Bohn, S. & Ilie, N. J. I. E. J. Wetting behaviour of silicone-and resin‐based root canal sealers. 47 , 542–549 (2014). Chen, W. P., Chen, Y. Y., Huang, S. H. & Lin, C. P. J. J. o. e. Limitations of push-out test in bond strength measurement. 39 , 283–287 (2013). Moinzadeh, A. T., Mirmohammadi, H., Hensbergen, I., Wesselink, P. & Shemesh, H. J. I. E. J. The correlation between fluid transport and push-out strength in root canals filled with a methacrylate‐based filling material. 48 , 193–198 (2015). Bergmans, L., Moisiadis, P., De Munck, J., Van Meerbeek, B. & Lambrechts, P. J. J. o. A. D. Effect of polymerization shrinkage on the sealing capacity of resin fillers for endodontic use. 7 (2005). Zaslansky, P., Currey, J. D., Friesem, A. A. & Weiner, S. J. J. o. b. o. Phase shifting speckle interferometry for determination of strain and Young’s modulus of mineralized biological materials: a study of tooth dentin compression in water. 10 , 024020–024020 (2005). Gurgel-Filho, E. D. et al. Comparative evaluation of push-out bond strength of a MTA-based root canal sealer. 13 , 114–117 (2014). Khurana, N. et al. Effect of drying protocols on the bond strength of bioceramic, MTA and resin-based sealer obturated teeth. 12 , 33 (2019). Engel, G. T., Goodell, G. G. & McClanahan, S. B. J. J. o. E. Sealer penetration and apical microleakage in smear-free dentin after a final rinse with either 70% isopropyl alcohol or Peridex. 31 , 620–623 (2005). Zmener, O., Pameijer, C. H., Serrano, S. A., Vidueira, M. & Macchi, R. L. J. J. o. e. Significance of moist root canal dentin with the use of methacrylate-based endodontic sealers: an in vitro coronal dye leakage study. 34 , 76–79 (2008). McMichael, G. E., Primus, C. M. & Opperman, L. A. J. J. o. e. Dentinal tubule penetration of tricalcium silicate sealers. 42, 632–636 (2016). Srikanth, P. et al. Minimal apical enlargement for penetration of irrigants to the apical third of root canal system: a scanning electron microscope study. 7 , 92 (2015). Torabinejad, M. et al. A new solution for the removal of the smear layer. 29 , 170–175 (2003). Migliau, G. et al. Comparison of two root canal filling techniques: Obturation with guttacore carrier based system and obturation with guttaflow2 fluid gutta-percha. 10 , 71 (2022). Aly, Y. & El Shershaby, S. J. C. S. I. Evaluation of push out bond strength of different endodontic sealers with different obturation techniques. 9 , 455–461 (2020). Formosa, L., Mallia, B. & Camilleri, J. J. I. e. j. Push-out bond strength of MTA with antiwashout gel or resins. 47 , 454–462 (2014). Tables Table 1 Descriptive statistics of push-out bond strength (MPa) values in the studied sample for AH Plus sealer across different canal regions (coronal, middle, and apical) under three drying protocols: paper point, 70% isopropyl alcohol, and 95% ethanol. * Mean ± t SD of push-out bond strength (MPa) Drying protocol Coronal Middle Apical Paper point * 3.65 ± t 0.19 * 3.10 ± t 0.30 * 2.61 ± t 0.49 70% Isopropanol * 5.96 ± t 0.53 * 5.45 ± t 0.31 * 4.74 ± t 0.32 95% Ethanol * 5.14 ± t 0.31 * 4.45 ± t 0.42 * 3.83 ± t 0.36 Table 2 Failure mode distribution at each root third (coronal, middle, and apical) of AH Plus sealer and vertical compaction Root sections Drying protocol Failure mode All sections Cohesive (%) Adhesive (%) Mix (%) Coronal Paper point 6 (60%) 10 (10 % ) 3 (30%) 10 70% Isopropanol 8 (80%) 0 (0%) 2 (20%) 10 95% Ethanol 8 (80%) 0 (0%) 2 (20%) 10 Middle Paper point 7 (70%) 0 (0%) 3 (30%) 10 70% Isopropanol 7 (70 % ) 0 (0%) 3 (30%) 10 95% Ethanol 6 (60%) 0 (0%) 4 (40%) 10 Apical Paper point 2 (20%) 2 (20 % ) 6 (60%) 10 70% Isopropanol 7 (70 % ) 0 (0%) 3 (30%) 10 95%Ethanol 6 (60%) 0 (0%) 4 (40%) 10 Additional Declarations No competing interests reported. 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Ayoubi","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Helen","middleName":"Rushdi","lastName":"Ayoubi","suffix":""},{"id":575909454,"identity":"2b22e708-c5d7-4164-8081-9d02b2410706","order_by":2,"name":"Alaa Alhomsi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA9klEQVRIiWNgGAWjYDACduYGBoaCA0AWY8OBD0CKjZ2QFmZGoBYDsJbGgzNAWpiJ18LAfJgHTBHQwd/M2Pjhh8EdOd3+ww2HbX5tk+djZmD88DEHtxaJw4zNkj0Gz4zNbiQ2HM7tu23YxszALDlzGx5rDjM2SPAYHE7cdoMRqKXnNiNQCxszLx4t8kBbfv4BaTl/sOGwZc9te4JaDA4ztkmDbTkAdBjDj9uJBLUYArVYyxgcBvvlYG/D7eQ2ZqDv8PlF7njz4ZtvKg7LmZ0//vjDjz+3bee3Nx/88BGf91EAYxuYbCBWPQj8IUXxKBgFo2AUjBQAAJrPWgM3pcUEAAAAAElFTkSuQmCC","orcid":"","institution":"","correspondingAuthor":true,"prefix":"","firstName":"Alaa","middleName":"","lastName":"Alhomsi","suffix":""}],"badges":[],"createdAt":"2025-12-25 19:23:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8450719/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8450719/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":100595920,"identity":"93a9b769-5d74-4e53-9da1-30386d601691","added_by":"auto","created_at":"2026-01-19 13:49:41","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":6783461,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript1.docx","url":"https://assets-eu.researchsquare.com/files/rs-8450719/v1/ed2e4c4b9f3c87e7136551cc.docx"},{"id":100569991,"identity":"b0afd714-10b7-4198-8006-fbe7b08ef088","added_by":"auto","created_at":"2026-01-19 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13:50:13","extension":"xml","order_by":13,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":89990,"visible":true,"origin":"","legend":"","description":"","filename":"2c9d77c26c3d41a183dc5d1ff19ae2231structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-8450719/v1/f618e15e0ad22946acf96737.xml"},{"id":100570001,"identity":"747ee6a7-5863-4e52-b77e-8bd69d70cfb6","added_by":"auto","created_at":"2026-01-19 09:36:28","extension":"html","order_by":14,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":100531,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8450719/v1/da9945d8384822beba8db452.html"},{"id":100595453,"identity":"8e7c968c-e7dc-4792-993f-a143fc216ce8","added_by":"auto","created_at":"2026-01-19 13:48:30","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1149823,"visible":true,"origin":"","legend":"\u003cp\u003eUniversal testing machine for the push-out test, the shaft (yellow arrow) was placed over the tooth slice (blue arrow).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8450719/v1/4e4abd05815a45a072be833f.png"},{"id":100569990,"identity":"812ce555-f791-47d6-a680-64ae6eb19bd8","added_by":"auto","created_at":"2026-01-19 09:36:28","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":426675,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA to C:\u003c/strong\u003e (A) Adhesive failure; (B) Cohesive failure; (C) Mixed failure (Stereomicroscopic image under 40× magnification)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8450719/v1/1d2801e1527ba289804e7021.png"},{"id":102815064,"identity":"f3fe9e95-5086-4e49-becd-af6e27d98cdc","added_by":"auto","created_at":"2026-02-17 05:25:57","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3103629,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8450719/v1/d4ba3e87-c1f7-48f7-bf75-a5b8e7146628.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The Effect of Different Drying Protocols on the Bond Strength of AH Plus Sealer Using Vertical Condensation Technique. (A Comparative in Vitro Study)","fulltext":[{"header":"1-Introduction","content":"\u003cdiv class=\"Heading\"\u003e\u003cb\u003e1-Introduction\u003c/b\u003e:\u003c/div\u003e \u003cp\u003eSuccessful endodontic therapy relies on a sequence of interdependent procedures designed to eliminate infection, prevent reinfection, and preserve the function of the treated tooth \u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e. The quality of root canal obturation has been identified as a critical determinant of endodontic treatment success.\u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e The complex anatomy of the endodontic system, characterized by irregularities, fins, isthmuses, and lateral canals, makes the three-dimensional obturation complicated.\u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003eThis anatomical complexity underscores the essential role of three in achieving long-term clinical success, which aims to fill the entire root canal system, including its accessory and irregular components \u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eModern obturation materials, such as gutta-percha in combination with advanced sealers, were engineered to adapt closely to canal walls and penetrate microscopic irregularities, enhancing the quality of the seal.\u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e In endodontic research, epoxy resin\u0026ndash;based sealers, such as AH Plus (Dentsply, Germany), are frequently used as a control material because of their reduced solubility, long-term dimensional stability, sealing capacity, radiopacity, and adequate micro retention to dentin\u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eAdvancements in obturation techniques, such as warm vertical compaction, have significantly improved the clinician\u0026rsquo;s ability to achieve a dense, homogeneous fill and enhance the flow of obturation materials into lateral canals and complex anatomical spaces that would otherwise remain unfilled using traditional cold lateral compaction. Numerous studies have demonstrated that three-dimensional obturation reduces microleakage and improves the long-term prognosis of endodontically treated teeth \u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eIn this regard, the presence of moisture within the root canal system, including the dentinal tubules, can occupy space and hinder the penetration of filling materials.\u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e Although paper points are the most commonly used method for canal drying in clinical practice, the moisture may persist in irregular canal regions and lateral canals even after their use \u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e. Moisture can interfere with the setting of root canal sealers by altering their working and setting times. It may also hinder sealer penetration and reduce bond strength to dentin\u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eSince no standardized protocol exists to achieve the ideal residual moisture, several chemicals, including alcohol, have been evaluated for their potential to improve dentinal wettability \u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eEthanol and isopropanol are widely used adjuncts in endodontic practice due to their strong ability to displace residual moisture from dentinal surfaces. Ethanol, particularly at high concentrations such as 95%, isopropanol, commonly used at 70%. This process reduces surface tension, increases dentinal surface energy, and lowers the contact angle, thereby improving dentinal wettability and facilitating better sealer penetration and adhesion \u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eAlthough laboratory studies have investigated the effect of Despite the availability of laboratory studies evaluating the effect of ethanol \u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e, isopropanol\u003csup\u003e\u003cb\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e, or paper point drying on dentin adhesion and AH Plus performance, no investigation has simultaneously compared these protocols or integrated them with warm vertical compaction technique using AH Plus. This gap highlights the need for comprehensive studies addressing the combined impact of different drying methods within clinically relevant obturation protocols.\u003c/p\u003e \u003cp\u003eTherefore, this study aimed to evaluate and compare the push-out bond strength and failure modes of the epoxy-based sealer AH Plus, used in warm vertical compaction, after three distinct canal drying protocols: paper points, 70% isopropanol alcohol and 95% ethanol alcohol.\u003c/p\u003e"},{"header":"2- Materials and Methods","content":"\u003cp\u003e\u003cstrong\u003eEthical approval\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003eThis study was conducted in accordance with the ethical approval from the Local Ethics Committee of Damascus University (No. 3227). It followed the CRIS Guidelines (Checklist for Reporting In-Vitro Studies).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStudy design and teeth selection:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAn experimental study was performed at the Faculty of Dental Medicine, Damascus University, at the Department of Endodontics and Operative Dentistry, from June 2024 to August 2025. Thirty single-rooted and single-canaled human permanent teeth were used. G*Power 3.1 software was used to calculate the sample size, based on a study by Jia-Sha Wang et al, that employed a similar methodology\u003cstrong\u003e\u003csup\u003e13\u003c/sup\u003e\u003c/strong\u003e. The power was estimated to be 90%, the probability of Type 1 error or α as 0.05, with an effect size (f) = 0.53, resulting in a total sample size of 30 teeth.\u003c/p\u003e\n\u003cp\u003eThe teeth were freshly extracted due to caries or periodontal disease,\u0026nbsp;and they were taken from the department of oral and maxillofacial surgery in faculty of dental medicine-Damascus university, \u0026nbsp;after obtaining informed consent from the patients to include the extracted teeth in the study, this is within the approval obtained from the university to conduct the research.\u0026nbsp;No tooth extraction in particular was performed to use in this study. The soft tissue residue on the extracted teeth was removed, and then the teeth were stored in water at 4°C and used within one month after extraction\u003cstrong\u003e\u003csup\u003e14\u003c/sup\u003e\u003c/strong\u003e. Only premolars classified as type 1 according to Vertucci classification were included in the study\u003cstrong\u003e\u003csup\u003e15\u003c/sup\u003e\u003c/strong\u003e. Teeth with an open apex, resorption, or curved canals, and the tooth that was previously endodontically treated were excluded.\u0026nbsp;Additionally, mesio-distal digital dental radiographies were used to evaluate the root canal anatomies of all the teeth, and the dentine thickness to exclude any teeth with less than 1mm dentine thickness. Then they were all examined under a stereomicroscope (Meiji Techno, Saitama, Japan) at a 20X magnification to exclude previously cracked and fractured teeth.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eProcedure:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFirst, the specimens were decoronated by transversely sectioning the roots at 15 mm, with a double-faced diamond disc (Hager \u0026amp; Meisinger GmbH, Neuss, Germany) at a low-speed straight handpiece with an air/water spray coolant (Being, Foshan, China).\u003c/p\u003e\n\u003cp\u003ePatency was confirmed with a #10 K-file\u0026nbsp;(MANI, Japan), and the root canals were enlarged using Pro Taper Universal rotary instruments (Dentsply, Germany) according to the appropriate taper of each canal, then we reached the working length (1 mm from the apical foramen). The root canals were irrigated by using 2 mL of 5.25% sodium hypochlorite between each instrument. After preparation, the canals were irrigated with 2 mL of 17% EDTA (PH = 7.7) for 1\u0026nbsp;minute, followed by a final 5mL rinse with distilled water. Then, the appropriate master gutta-percha (GP) cones (Meta Biome, South Korea) were selected for each canal by ensuring that the cone reached the full working length with slight resistance upon withdrawal (Tug-Back). The 30 roots were randomly divided into three experimental groups (n = 10) for each group according to the drying protocol.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Group (1): The canals were blot dried using paper points (Meta Biome, South Korea) until complete dryness of the last point was confirmed visually\u003cstrong\u003e\u003csup\u003e13\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eGroup (2): After the removal of excess distilled water with paper points\u0026nbsp;until complete dryness of the last point was confirmed visually, the canals were filled with 10 mL 70% isopropanol (OQEMA GmbH, Mönchengladbach, Germany) using a syringe with a side-vented needle carried to the WL. After being left in the canal for 10 seconds, the isopropanol was removed with paper points\u003cstrong\u003e\u003csup\u003e13\u003c/sup\u003e\u003c/strong\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGroup (3): After the removal of excess distilled water with paper points\u0026nbsp;until complete dryness of the last point was confirmed visually, the canals were filled with 10 mL 95% ethanol (Chem-Lab NV, now AnalytiChem Belgium NV, Belgium) using a syringe with a side-vented needle carried to the WL. After being left in the canal for 10 seconds, the ethanol was removed with paper points\u003cstrong\u003e\u003csup\u003e13\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eThe samples were filled using a GP cone and AH plus sealer (Dentsply, Germany) following the manufacturer’s instructions, using the vertical condensation technique.\u003c/p\u003e\n\u003cp\u003eWarm vertical compaction was performed using a Fast Fill device (Eighteeth, Changzhou, China) set at 200 °C. The fastback tip was pre-fitted to a depth 4–5 mm short of the working length (WL).\u0026nbsp;Following placement of AH Plus, 0.5 mm of the master cone was clipped to prevent extrusion of thermoplasticized gutta-percha beyond the apex. The cone was then inserted, and the fastback tip advanced in a single motion to the predetermined depth. After cooling for 15 s, a one‑second heat burst was applied before withdrawing the tip. This procedure was repeated twice: first at the middle third and then at the coronal third of the canal. Excess gutta-percha at the canal orifice was removed and compacted using a 0.6 mm (No. ½) hand plugger (Dentsply, Tulsa, OK, USA).\u0026nbsp;Afterward, the canal orifice was restored using a temporary filling (Ghimas, Bologna, Italy)\u003c/p\u003e\n\u003cp\u003eThen all samples were stored in an incubator (Binder, Tuttlingen, Germany) at 37ºC and 100% humidity for 7 days to allow the complete setting of the sealers\u003cstrong\u003e\u003csup\u003e13\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePush\u003c/strong\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003cstrong\u003eout\u0026nbsp;strength\u003c/strong\u003e\u003cstrong\u003etest:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThree slices with 2-mm-thick (slice in the apical third, slice in the middle third, and slice in the coronal third) were cut at intervals of 3, 5, and 9 mm from the apical to coronal third (30 slices each group) with a low-speed fan empty diamond disc with a thickness of 0.25 mm at a slow rotational speed of 25,000 cycles per minute under heavy water cooling at three levels (Hager \u0026amp; Meisinger GmbH, Neuss, Germany).\u0026nbsp;The push-out test was performed using a Universal Testing Machine (Testometric Co. Ltd., Rochdale, UK), a crosshead speed of 1 mm/ min. Shafts with tip diameters of 0.4 mm, 0.8 mm, and 1.0 mm were used for the apical, middle, and coronal sections receptively\u0026nbsp;\u003cstrong\u003e\u003csup\u003e16\u003c/sup\u003e\u003c/strong\u003e\u003cstrong\u003e(Fig 1)\u003c/strong\u003e. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe push-out strength at failure was calculated in megapascals (MPa) by dividing the load in newtons (N) by the area of the bond interface:\u003cstrong\u003e\u003csup\u003e13\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Bond area: π(R+r) h\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;where π = 3.14\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eR: The radius of the canal close to the crown.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;r: The radius of the canal close to the apex.\u003c/p\u003e\n\u003cp\u003eBoth measurements were calculated using AutoCAD software.\u003c/p\u003e\n\u003cp\u003eh: The height of the slice in millimetres, which was standardized at 2 mm for all samples.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAnalysis of failure modes:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe failure modes were observed under a stereomicroscope at a 40× magnification. Failures were classified as follows \u003cstrong\u003e(Fig 2)\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Adhesive failure: Failure occurred between the sealer and the inner wall of the root canal.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCohesive failure: Failure occurred inside the sealer.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Mixed failure: The above failure modes both occurred.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStatistical analysis was conducted utilizing IBM SPSS software version 24 (IBM SPSS Statistics®\u0026nbsp;version 24, IBM Corp., New York, USA).Descriptive statistics were obtained for the measured forces (N) and expressed as stress values in megapascals (MPa).\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Data were first analysed with a One-way ANOVA test to determine if there were significant differences between Groups in the studied sample, and then the Bonferroni test was applied to make pair-wise comparisons. Data were analysed at a 95% confidence interval (P-value \u0026lt; 0.05).\u003c/p\u003e"},{"header":"3-Results","content":"\u003cp\u003e\u003cstrong\u003ePush-out strength:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere was a significant difference in push-out strength between the 3 moisture condition groups (P \u0026lt; 0.05). The push-out bond strength values varied significantly across the different drying protocols and root canal sections (coronal, middle, and apical). Specimens dried with 70% isopropanol exhibited the highest bond strength values in all thirds, with Mean ± Standard Deviation (SD) values of (5.96 ± 0.53 MPa, 5.45 ± 0.31 MPa, and 4.74 ± 0.32 MPa) in the coronal, middle, and apical third respectively. 95% Ethanol also enhanced bond strength compared to paper point drying, yielding (5.14 ± 0.31 MPa, 4.45 ± 0.42 MPa, and 3.83 ± 0.36 MPa) in the coronal, middle, and apical thirds, respectively. In contrast, the paper point protocol resulted in the lowest bond strength values across all thirds (3.65 ± 0.19 MPa, 3.10 ± 0.30 MPa, and 2.61 ± 0.49 MPa), respectively. A consistent trend of decreasing bond strength from coronal to apical thirds was observed within each protocol \u003cstrong\u003e(Table 1)\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFailure mode\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCohesive failure was the predominant mode across all root thirds, particularly in specimens dried with\u0026nbsp;70%\u0026nbsp;isopropanol and 95%\u0026nbsp;ethanol. In the coronal third, cohesive failures accounted for 80% of samples in both alcohol-based protocols, compared to 60% with paper point drying. Mixed failures were more frequent with paper point (30%) than with isopropanol or ethanol (20%). Adhesive failures were only observed in the coronal third with paper point drying (10%).\u003c/p\u003e\n\u003cp\u003eIn the middle third, cohesive failures ranged from 60% to 70%, with ethanol showing the highest proportion of mixed failures (40%). No adhesive failures were detected in this third under any protocol.\u003c/p\u003e\n\u003cp\u003eIn the apical third, paper point drying resulted in the lowest cohesive failure rate (20%) and the highest mixed failure rate (60%), along with 20% adhesive failures. In contrast, isopropanol and ethanol protocols yielded higher cohesive failure rates (70% and 60%) respectively, and no adhesive failures \u003cstrong\u003e(Table2)\u003c/strong\u003e.\u003c/p\u003e"},{"header":"4- Discussion","content":"\u003cp\u003eThe growing interest in adhesive endodontics has driven the development of various resin-based root canal sealers. Although many of these sealers exhibit suboptimal bond strength to dentin, achieving reliable adhesion remains essential for preserving the integrity of the sealer–dentin interface under mechanical stresses induced by tooth flexure, clinical procedures, or subsequent post space preparation\u0026nbsp;\u003cstrong\u003e\u003csup\u003e17\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eSealers are fundamental in the obturation process, as they significantly affect the overall quality of root canal treatment. Achieving strong adhesion between the sealer and the dentin wall is highly desirable, since it ensures the long-term stability and integrity of the sealer–dentin interface\u0026nbsp;\u003cstrong\u003e\u003csup\u003e18\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eAH Plus is considered the gold‑standard epoxy resin–based sealer due to its long‑term dimensional stability, low solubility, and reliable interaction with dentin\u003cstrong\u003e\u003csup\u003e19\u003c/sup\u003e\u003c/strong\u003e. When used with vertical compaction, its sealing ability is further enhanced as the thermoplasticized gutta‑percha adapts closely to canal irregularities and distributes the sealer into accessory canals and dentinal tubules. The combination of heat‑softened gutta‑percha and the sealer’s minimal shrinkage results in a more homogeneous three‑dimensional fill and a durable apical seal, reinforcing its role as a reference material for evaluating newer sealers\u0026nbsp;\u003cstrong\u003e\u003csup\u003e19\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003ePush-out strength is commonly employed as an indicator of the adhesion between obturation materials and root canal walls due to its methodological simplicity and reproducibility\u0026nbsp;\u003cstrong\u003e\u003csup\u003e20\u003c/sup\u003e\u003c/strong\u003e. This parameter reflects a composite measure encompassing the frictional resistance at the material–dentin interface, intermolecular bonding forces, and chemical adhesion to root dentin\u003cstrong\u003e\u003csup\u003e21\u003c/sup\u003e\u003c/strong\u003e. Additionally, push-out strength is influenced by factors such as frictional forces\u003cstrong\u003e\u003csup\u003e22\u003c/sup\u003e\u003c/strong\u003e, Polymerization shrinkage factor (C-factor)\u0026nbsp;\u003cstrong\u003e\u003csup\u003e23,24\u003c/sup\u003e\u003c/strong\u003e,and different root canal treatment protocols\u003cstrong\u003e\u003csup\u003e25\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eIt is suggested that the push-out test offers a more accurate evaluation of adhesive strength than the traditional shear test\u0026nbsp;\u003cstrong\u003e\u003csup\u003e26\u003c/sup\u003e\u003c/strong\u003e. This is primarily because the push-out test induces fracture parallel to the dentin–sealer interface, thereby representing a true shear stress condition in specimens with parallel-sided geometry\u0026nbsp;\u003cstrong\u003e\u003csup\u003e26\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eIn this study, the drying protocols exerted distinct influences on the push-out bond strength and the penetration of resin-based sealer into dentinal tubules. Canals dried with 70% isopropanol or 95% ethanol exhibited significantly greater bond strength compared to those dried with paper points. Conversely, canals dried with 70% isopropanol showed the highest bond strength overall.\u0026nbsp;Paper points rely on the principle of direct contact and capillary action to absorb and adsorb water. However, due to the complex anatomy of the root canal system, some residual moisture may remain, forming a non-displaceable physical barrier that can hinder the complete penetration of endodontic\u0026nbsp;\u003cstrong\u003e\u003csup\u003e27\u003c/sup\u003e\u003c/strong\u003e. However, Nagas et al, found that moisture remained in the irregular regions of the canal and in lateral canals after drying with paper points. This residual moisture may hinder complete sealer penetration and compromise the bond strength to dentin. Such findings highlight the limitations of paper point drying alone\u0026nbsp;\u003cstrong\u003e\u003csup\u003e8\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eSeveral factors may explain why isopropanol provides stronger sealer–dentin adhesion compared to ethanol; Considering the hydrophilic propensity of the resin-based sealers, it may be speculated that isopropyl alcohol (C\u003csub\u003e3\u003c/sub\u003eH\u003csub\u003e7\u003c/sub\u003eOH), which has lower polarity than ethanol (C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e5\u003c/sub\u003eOH), promoted less removal of the water from dentinal tubules, enhancing the dentin wettability, increasing the degree of conversion of the sealers\u0026nbsp;\u003cstrong\u003e\u003csup\u003e28\u003c/sup\u003e\u003c/strong\u003e, Ethanol at high concentrations can excessively dehydrate the collagen network within dentin, leading to partial collapse of its structure\u0026nbsp;\u003cstrong\u003e\u003csup\u003e10\u003c/sup\u003e\u003c/strong\u003e. Unlike ethanol, isopropanol leaves a small amount of residual moisture within the dentin collagen matrix, helping preserve its structural flexibility and allowing improved sealer penetration\u0026nbsp;\u003cstrong\u003e\u003csup\u003e12\u003c/sup\u003e\u003c/strong\u003e. Moreover, resin-based sealers often require a slightly moist environment to optimize polymerization. Isopropanol provides this balanced condition, whereas ethanol may leave an overly dry surface that reduces the degree of conversion. Additionally, due to its viscosity and physical properties, isopropanol may facilitate deeper penetration into dentinal tubules compared to ethanol, thereby enhancing mechanical contact between the sealer and dentin\u0026nbsp;\u003cstrong\u003e\u003csup\u003e29\u003c/sup\u003e\u003c/strong\u003e\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthanol evaporates rapidly, causing excessive dehydration and collagen shrinkage, whereas isopropanol’s slower evaporation maintains a more stable dentinal surface for sealer adhesion\u0026nbsp;\u003cstrong\u003e\u003csup\u003e29\u003c/sup\u003e\u003c/strong\u003e\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe differences in push-out bond strength among the coronal, middle, and apical thirds can be explained by several factors. The coronal third generally exhibits the highest values due to greater dentinal tubule density\u0026nbsp;\u003cstrong\u003e\u003csup\u003e30\u003c/sup\u003e\u003c/strong\u003e,more effective irrigant penetration\u0026nbsp;\u003cstrong\u003e\u003csup\u003e31\u003c/sup\u003e\u003c/strong\u003e,and easier smear layer removal\u0026nbsp;\u003cstrong\u003e\u003csup\u003e32\u003c/sup\u003e\u003c/strong\u003e. In addition, condensation of the sealer and gutta-percha is more efficient in this region because of the wider canal diameter and better accessibility\u0026nbsp;\u003cstrong\u003e\u003csup\u003e33\u003c/sup\u003e\u003c/strong\u003e. The middle third showed moderate bond strength, reflecting a gradual decrease in tubule density and slightly reduced efficiency of condensation, although irrigants and sealers can still penetrate adequately. Conversely, the apical third demonstrates the lowest bond strength, which may be attributed to reduce tubule density, complex apical anatomy, limited irrigant penetration, residual smear layer, and less effective condensation due to restricted access and narrow canal dimensions\u0026nbsp;\u003cstrong\u003e\u003csup\u003e12\u003c/sup\u003e\u003c/strong\u003e\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFurthermore, Instrumentation pressure during mechanical preparation may induce subtle alterations in the canal walls, with a more pronounced effect in the coronal and middle thirds compared to the apical third.\u0026nbsp;\u003cstrong\u003e\u003csup\u003e34\u003c/sup\u003e\u003c/strong\u003eThese changes influence the surface characteristics available for bonding and may partly explain the higher bond strength observed coronally and in the middle segment. In addition, sealer distribution tends to be more uniform in the coronal and middle thirds, whereas in the apical third, the narrower canal diameter and complex anatomy often lead to uneven accumulation of the sealer\u003cstrong\u003e\u003csup\u003e34\u003c/sup\u003e\u003c/strong\u003e.Together, these factors contribute to the differences in push‑out bond strength among the three canal regions.\u003c/p\u003e\n\u003cp\u003eCanals dried with 70% isopropanol or 95% ethanol alcohol showed no adhesive failure along the sealer and inner wall of the root canal, a result that may be partly attributed to the bonding forces established between the sealer and the dentinal surface. In contrast, adhesive failure was observed when canals were dried using paper points alone, highlighting the influence of the drying protocol on the integrity of the sealer–dentin interface\u0026nbsp;\u003cstrong\u003e\u003csup\u003e8\u003c/sup\u003e\u003c/strong\u003e\u003cstrong\u003e.\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWhile canals dried with 70% isopropanol, Ethanol 95% a relatively high cohesive failure mode was observed, which may suggest that alcohol allows for a stronger interaction with the canal dentin wall. Mixed failure was observed in 60% of the apical third specimens in the paper‑points group, whereas 20% exhibited adhesive failure. This pattern may be partly explained by the complex apical anatomy, including the presence of secondary canals, which can hinder sealer solidification and limit its interaction with the canal walls\u003cstrong\u003e\u003csup\u003e13\u003c/sup\u003e\u003c/strong\u003e.\u0026nbsp;Notably, the incidence of mixed failure decreased to 40% in the apical third when canals were dried using ethanol,\u0026nbsp;and further declined to 30% when isopropanol was applied. Under these drying conditions, cohesive failure became more predominant, suggesting improved sealer adaptation and stronger interaction with the dentinal walls\u003cstrong\u003e\u003csup\u003e35\u003c/sup\u003e\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eTo validate and extend these findings beyond the in‑vitro setting, future clinical trials that closely replicate the current experimental design are strongly recommended. Such investigations would enable the translation of laboratory outcomes into clinical practice, thereby substantiating the clinical relevance of isopropanol drying as a final step in root canal preparation and confirming its potential to enhance the long‑term success of obturation.\u003c/p\u003e"},{"header":"5- Conclusion","content":"\u003cp\u003eWithin the limitations of this \u003cem\u003ein vitro\u003c/em\u003e study,\u0026nbsp;drying the canals with 70% isopropyl alcohol yielded the highest bond strength between AH Plus sealer and dentinal tubules when using the warm vertical condensation technique. Although 95% ethanol also improved bonding, its effect remained inferior to 70% isopropanol alcohol, while the paper‑points method consistently produced the lowest values. These findings highlight the clear superiority of alcohol‑based drying protocols over conventional drying approaches.\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthors' contributions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAmira Arar, contributed to drafting, reviewing and editing. The author read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003eHelen Rushdi Ayoubi, the supervisor, contributed to mentoring, reviewing and editing. The author read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eAlaa Alhomsi\u003csup\u003e*\u003c/sup\u003e,\u003c/u\u003e contributed to drafting, reviewing and editing, corresponding. The author read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability statement:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analysed during this study are included in this published article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding Information:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no sources of funding. \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict Of Interest:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eEthics Approval Statement:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study protocol received approval from the Damascus University Ethics Committee (Date 2023/No. 3227).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003econsent approval was received from the patients before teeth extraction, to be used in laboratory research.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eFoschi, F. \u003cem\u003ein Common Complications in Endodontics: Prevention and Management\u003c/em\u003e 183\u0026ndash;207 (Springer, 2025).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e\u0026Oslash;rstavik, D., Qvist, V. \u0026amp; Stoltze, K. J. E. j. o. o. s. A multivariate analysis of the outcome of endodontic treatment. 112, 224\u0026ndash;230 (2004).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDzankovic, A., Korac, S. \u0026amp; Tahmiscija, I. Endodontic Challenges Arising from Root Canal Morphology. (2024).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVersiani, M., Martins, J. \u0026amp; Ordinola-Zapata, R. J. A. d. j. Anatomical complexities affecting root canal preparation: a narrative review. \u003cb\u003e68\u003c/b\u003e, S5\u0026ndash;S23 (2023).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhou, H. et al. Physical properties of 5 root canal sealers. \u003cb\u003e39\u003c/b\u003e, 1281\u0026ndash;1286 (2013).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCarneiro, S. et al. Push-out strength of root fillings with or without thermomechanical compaction. \u003cb\u003e45\u003c/b\u003e, 821\u0026ndash;828 (2012).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAminsobhani, M. et al. Coronal microleakage in root canals obturated with lateral compaction, warm vertical compaction and guttaflow system. \u003cb\u003e5\u003c/b\u003e, 83 (2010).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNagas, E. et al. Dentin moisture conditions affect the adhesion of root canal sealers. \u003cb\u003e38\u003c/b\u003e, 240\u0026ndash;244 (2012).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEhsani, M., Dehghani, A., Abesi, F., Khafri, S. \u0026amp; Dehkordi, S. G. J. J. o. d. r., dental clinics, dental prospects. Evaluation of apical micro-leakage of different endodontic sealers in the presence and absence of moisture. 8, 125 (2014).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGr\u0026eacute;goire, G., Sharrock, P. \u0026amp; Tavernier, B. J. O. H. \u0026amp; Care. Dentinal variations after application of an adhesive containing isopropanol used in etch and rinse mode on moist and dried dentin. \u003cb\u003e4\u003c/b\u003e, 1\u0026ndash;5 (2019).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAyar, M. K. J. E. j. o. d. A review of ethanol wet-bonding: Principles and techniques. 10, 155\u0026ndash;159 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePantoja, C. A. et al. Influence of ethanol on dentin roughness, surface free energy, and interaction between AH Plus and root dentin. \u003cb\u003e32\u003c/b\u003e, e33 (2018).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDias, K. C. et al. Influence of drying protocol with isopropyl alcohol on the bond strength of resin-based sealers to the root dentin. \u003cb\u003e40\u003c/b\u003e, 1454\u0026ndash;1458 (2014).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang, J. S., Bai, W., Wang, Y. \u0026amp; Liang, Y. H. J. J. o. D. S. Effect of different dentin moisture on the push-out strength of bioceramic root canal sealer. \u003cb\u003e18\u003c/b\u003e, 129\u0026ndash;134 (2023).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMobarak, E. H., El-Badrawy, W., Pashley, D. H. \u0026amp; Jamjoom, H. J. T. J. o. p. d. Effect of pretest storage conditions of extracted teeth on their dentin bond strengths. \u003cb\u003e104\u003c/b\u003e, 92\u0026ndash;97 (2010).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVertucci, F. J. J. O. s., oral medicine, oral pathology. \u003cem\u003eRoot canal Anat. Hum. permanent teeth\u003c/em\u003e. \u003cb\u003e58\u003c/b\u003e, 589\u0026ndash;599 (1984).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFrasquetti, K. S. et al. Effect of different root canal drying protocols on the bond strength of two bioceramic sealers. \u003cb\u003e17\u003c/b\u003e, 1229\u0026ndash;1234 (2023).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAlmutairi, N. M. et al. Sealing ability and micro leakage of AH26 and AH plus root canal sealers: A systematic review. \u003cb\u003e14\u003c/b\u003e, 140\u0026ndash;146 (2023).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAttash, I. \u0026amp; Wiaam, A. A. J. A.-R. D. J. Push-out Bond Strength Evaluation for Different Endodontic Sealers (A Comparative Study). \u003cb\u003e22\u003c/b\u003e, 301\u0026ndash;312 (2022).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e\u0026Aacute;lvarez V\u0026aacute;squez, J. L. Epoxy resin-based root canal sealers: an integrative literature review. (2024).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRazmi, H., Bolhari, B., Dashti, N. K. \u0026amp; Fazlyab, M. J. I. e. j. The effect of canal dryness on bond strength of bioceramic and epoxy-resin sealers after irrigation with sodium hypochlorite or chlorhexidine. \u003cb\u003e11\u003c/b\u003e, 129 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBohn, S. \u0026amp; Ilie, N. J. I. E. J. Wetting behaviour of silicone-and resin‐based root canal sealers. \u003cb\u003e47\u003c/b\u003e, 542\u0026ndash;549 (2014).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen, W. P., Chen, Y. Y., Huang, S. H. \u0026amp; Lin, C. P. J. J. o. e. Limitations of push-out test in bond strength measurement. \u003cb\u003e39\u003c/b\u003e, 283\u0026ndash;287 (2013).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoinzadeh, A. T., Mirmohammadi, H., Hensbergen, I., Wesselink, P. \u0026amp; Shemesh, H. J. I. E. J. The correlation between fluid transport and push-out strength in root canals filled with a methacrylate‐based filling material. \u003cb\u003e48\u003c/b\u003e, 193\u0026ndash;198 (2015).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBergmans, L., Moisiadis, P., De Munck, J., Van Meerbeek, B. \u0026amp; Lambrechts, P. J. J. o. A. D. Effect of polymerization shrinkage on the sealing capacity of resin fillers for endodontic use. 7 (2005).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZaslansky, P., Currey, J. D., Friesem, A. A. \u0026amp; Weiner, S. J. J. o. b. o. Phase shifting speckle interferometry for determination of strain and Young\u0026rsquo;s modulus of mineralized biological materials: a study of tooth dentin compression in water. \u003cb\u003e10\u003c/b\u003e, 024020\u0026ndash;024020 (2005).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGurgel-Filho, E. D. et al. Comparative evaluation of push-out bond strength of a MTA-based root canal sealer. \u003cb\u003e13\u003c/b\u003e, 114\u0026ndash;117 (2014).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKhurana, N. et al. Effect of drying protocols on the bond strength of bioceramic, MTA and resin-based sealer obturated teeth. \u003cb\u003e12\u003c/b\u003e, 33 (2019).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEngel, G. T., Goodell, G. G. \u0026amp; McClanahan, S. B. J. J. o. E. Sealer penetration and apical microleakage in smear-free dentin after a final rinse with either 70% isopropyl alcohol or Peridex. \u003cb\u003e31\u003c/b\u003e, 620\u0026ndash;623 (2005).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZmener, O., Pameijer, C. H., Serrano, S. A., Vidueira, M. \u0026amp; Macchi, R. L. J. J. o. e. Significance of moist root canal dentin with the use of methacrylate-based endodontic sealers: an in vitro coronal dye leakage study. \u003cb\u003e34\u003c/b\u003e, 76\u0026ndash;79 (2008).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMcMichael, G. E., Primus, C. M. \u0026amp; Opperman, L. A. J. J. o. e. Dentinal tubule penetration of tricalcium silicate sealers. 42, 632\u0026ndash;636 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSrikanth, P. et al. Minimal apical enlargement for penetration of irrigants to the apical third of root canal system: a scanning electron microscope study. \u003cb\u003e7\u003c/b\u003e, 92 (2015).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTorabinejad, M. et al. A new solution for the removal of the smear layer. \u003cb\u003e29\u003c/b\u003e, 170\u0026ndash;175 (2003).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMigliau, G. et al. Comparison of two root canal filling techniques: Obturation with guttacore carrier based system and obturation with guttaflow2 fluid gutta-percha. \u003cb\u003e10\u003c/b\u003e, 71 (2022).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAly, Y. \u0026amp; El Shershaby, S. J. C. S. I. Evaluation of push out bond strength of different endodontic sealers with different obturation techniques. \u003cb\u003e9\u003c/b\u003e, 455\u0026ndash;461 (2020).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFormosa, L., Mallia, B. \u0026amp; Camilleri, J. J. I. e. j. Push-out bond strength of MTA with antiwashout gel or resins. \u003cb\u003e47\u003c/b\u003e, 454\u0026ndash;462 (2014).\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":" \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cdiv class=\"SimplePara\"\u003eDescriptive statistics of push-out bond strength (MPa) values in the studied sample for AH Plus sealer across different canal regions (coronal, middle, and apical) under three drying protocols: paper point, 70% isopropyl alcohol, and 95% ethanol. \u003csup\u003e*\u003c/sup\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003eSD of push-out bond strength (MPa)\u003c/div\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cdiv class=\"SimplePara\"\u003eDrying protocol\u003c/div\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003eCoronal\u003c/div\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003eMiddle\u003c/div\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cdiv class=\"SimplePara\"\u003eApical\u003c/div\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cdiv class=\"SimplePara\"\u003ePaper point\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003csup\u003e*\u003c/sup\u003e3.65\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003e0.19\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003csup\u003e*\u003c/sup\u003e3.10\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003e0.30\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c8\" namest=\"c7\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003csup\u003e*\u003c/sup\u003e2.61\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003e0.49\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cdiv class=\"SimplePara\"\u003e70% Isopropanol\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003csup\u003e*\u003c/sup\u003e5.96\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003e0.53\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003csup\u003e*\u003c/sup\u003e5.45\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003e0.31\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c8\" namest=\"c7\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003csup\u003e*\u003c/sup\u003e4.74\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003e0.32\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cdiv class=\"SimplePara\"\u003e95% Ethanol\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003csup\u003e*\u003c/sup\u003e5.14\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003e0.31\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003csup\u003e*\u003c/sup\u003e4.45\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003e0.42\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003csup\u003e*\u003c/sup\u003e3.83\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003csup\u003et\u003c/sup\u003e0.36\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003cbr/\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cdiv class=\"SimplePara\"\u003eFailure mode distribution at each root third (coronal, middle, and apical) of AH Plus sealer and vertical compaction\u003c/div\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cdiv class=\"SimplePara\"\u003eRoot sections\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cdiv class=\"SimplePara\"\u003eDrying protocol\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003eFailure mode\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cdiv class=\"SimplePara\"\u003eAll sections\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003eCohesive (%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003eAdhesive (%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003eMix (%)\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cdiv class=\"SimplePara\"\u003eCoronal\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003ePaper point\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003e6 (60%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e10 (10\u003c/span\u003e%\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e)\u003c/span\u003e\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003e3 (30%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e10\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003e70% Isopropanol\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e8 (80%)\u003c/span\u003e\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e0 (0%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003e2 (20%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e10\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003e95% Ethanol\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e8 (80%)\u003c/span\u003e\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e0 (0%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003e2 (20%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e10\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cdiv class=\"SimplePara\"\u003eMiddle\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003ePaper point\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003e7 (70%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e0 (0%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003e3 (30%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e10\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003e70% Isopropanol\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e7 (70\u003c/span\u003e%\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e)\u003c/span\u003e\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e0 (0%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003e3 (30%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e10\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003e95% Ethanol\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003e6 (60%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e0 (0%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003e4 (40%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e10\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cdiv class=\"SimplePara\"\u003eApical\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003ePaper point\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003e2 (20%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e2 (20\u003c/span\u003e%\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e)\u003c/span\u003e\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003e6 (60%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e10\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003e70% Isopropanol\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003e\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e7 (70\u003c/span\u003e%\u003cspan type=\"Bold\" class=\"Bold\" name=\"Emphasis\"\u003e)\u003c/span\u003e\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e0 (0%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003e3 (30%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e10\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cdiv class=\"SimplePara\"\u003e95%Ethanol\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cdiv class=\"SimplePara\"\u003e6 (60%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cdiv class=\"SimplePara\"\u003e0 (0%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cdiv class=\"SimplePara\"\u003e4 (40%)\u003c/div\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cdiv class=\"SimplePara\"\u003e10\u003c/div\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003cbr/\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"70% Isopropanol, 95% Ethanol, Paper Points, AH Plus Sealer, Vertical Condensation","lastPublishedDoi":"10.21203/rs.3.rs-8450719/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8450719/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjectives\u003c/h2\u003e \u003cp\u003eThe purpose of this \u003cem\u003ein vitro\u003c/em\u003e study was to evaluate the effects of isopropanol alcohol, ethanol alcohol when used for final irrigation and the paper points as drying protocols, on the bond strength of AH Plus sealer using the warm vertical condensation technique.\u003c/p\u003e\u003ch2\u003eMaterials and Methods\u003c/h2\u003e \u003cp\u003eThirty single-rooted human permanent teeth were decoronated to a length of 15 mm. The roots were randomly divided into three groups (n\u0026thinsp;=\u0026thinsp;10 for each group) according to the drying protocol: (G1: Paper points, G2: 70% Isopropanol, and G3: 95%Ethanol). Thirty roots were prepared by using Pro Taper universal rotary instruments. G1: the canals were blot dried with paper points until the last one appeared dry, G2: the canals were dried with paper points followed by dehydration with 70% isopropanol, and G3: the canals were dried with paper points followed by dehydration with 95% ethanol. After drying, the canals were obturated with AH Plus sealer and gutta-percha (AH/GP) using the vertical condensation technique. Then, each root was sectioned into three slices with 2-mm-thick (coronal, middle, apical thirds) using a diamond disc. The push-out strength was tested for each slice between the sealer and dentin wall using a universal testing machine at a crosshead speed of 1 mm/min, and failure modes were examined under a stereomicroscope at a (40X) magnification. The data were statistically analysed using a One-way ANOVA test, this was followed by a pair-wise comparison using the Bonferroni test, and all data were analysed at a 95% confidence interval (P-value\u0026thinsp;\u0026le;\u0026thinsp;0.05).\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eResults showed that there were statistically significant differences for the studied three groups (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), where G2 exhibited significantly higher bond strength values compared to G3 (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), while the lowest push-out strength was observed in G1. For the failure modes, there were statistically significant differences in the failure mode between the three groups (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). For different levels of root, there were statistically significant differences (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05): the majority were cohesive failures 80%) in the coronal thirds of G2 and G3, while in G1, mixed failure was common, followed by adhesive failure to a lesser extent.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eWithin the limitations of this \u003cem\u003ein vitro\u003c/em\u003e study, drying with (70% Isopropanol, 95% Ethanol) enhanced the bond strength between AH Plus sealer and dentinal tubules more effectively than the conventional paper point drying method when using the warm vertical condensation technique, with 70% isopropanol superior to the rest of the studied groups.\u003c/p\u003e","manuscriptTitle":"The Effect of Different Drying Protocols on the Bond Strength of AH Plus Sealer Using Vertical Condensation Technique. (A Comparative in Vitro Study)","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-19 09:36:22","doi":"10.21203/rs.3.rs-8450719/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3f9890bb-44bf-4e04-b755-a41186b6f21d","owner":[],"postedDate":"January 19th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":61280649,"name":"Health sciences/Health care"},{"id":61280650,"name":"Health sciences/Medical research"}],"tags":[],"updatedAt":"2026-02-17T05:25:02+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-19 09:36:22","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8450719","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8450719","identity":"rs-8450719","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}