KACD
Articles
- Page Path
- HOME > Restor Dent Endod > Volume 43(2); 2018 > Article
- Research Article Effect of ultrasonic agitation on push-out bond strength and adaptation of root-end filling materials
-
Murilo Priori Alcalde1
, Rodrigo Ricci Vivan1, Marina Angélica Marciano2, Jussaro Alves Duque1, Samuel Lucas Fernandes1, Mariana Bailo Rosseto1, Marco Antonio Hungaro Duarte1 -
DOI: https://doi.org/10.5395/rde.2018.43.e23
Published online: April 27, 2018
1Department of Restorative Dentistry, Dental Materials and Endodontics, Bauru Dental School, University of São Paulo, Bauru, SP, Brazil.
2Department of Restorative Dentistry, School of Dentistry of Piracicaba, State University of Campinas, Piracicaba, SP, Brazil.
- Correspondence to: Jussaro Alves Duque, DDS, MS. PhD Student, Department of Restorative Dentistry, Dental Materials and Endodontics, Bauru Dental School, University of São Paulo, Al. Octávio Pinheiro Brisola No. 9-75 Bauru, SP 17012-901, Brazil. jussaroduque@usp.br
• Received: December 23, 2017 • Accepted: March 8, 2018
Copyright © 2018. The Korean Academy of Conservative Dentistry
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (https://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
- 22 Views
- 0 Download
Abstract
-
Objectives This study evaluated the effect of ultrasonic agitation of mineral trioxide aggregate (MTA), calcium silicate-based cement (CSC), and Sealer 26 (S26) on adaptation at the cement/dentin interface and push-out bond strength.
-
Materials and Methods Sixty maxillary canines were divided into 6 groups (n = 10): MTA, S26, and CSC, with or without ultrasonic activation (US). After obturation, the apical portions of the teeth were sectioned, and retrograde cavities were prepared and filled with cement by hand condensation. In the US groups, the cement was activated for 60 seconds: 30 seconds in the mesio-distal direction and 30 seconds in the buccal-lingual direction, using a mini Irrisonic insert coupled with the ultrasound transducer. After the materials set, 1.5-mm thick sections were obtained from the apexes. The presence of gaps and the bond between cement and dentin were analyzed using low-vacuum scanning electron microscopy. Push-out bond strength was measured using a universal testing machine.
-
Results Ultrasonic agitation increased the interfacial adaptation of the cements. The S26 US group showed a higher adaptation value than MTA (p < 0.05). US improved the push-out bond strength for all the cements (p < 0.05).
-
Conclusions The US of retrograde filling cements enhanced the bond to the dentin wall of the root-end filling materials tested.
INTRODUCTION
Endodontic surgery is a resource used in cases when conventional endodontic treatment fails. The surgical method involves the production of a cavity in the apical region with subsequent sealing using a retrograde filling material. For successful surgical therapy, good adaptation of this retrograde filling material to the dentin walls is extremely important, in order to prevent fluids from percolating into the canal space [1].
Mineral trioxide aggregate (MTA) is one of the most widely used materials for retrograde fillings [2]. This cement is widely known for its biological properties, which include stimulation of tissue repair and induction of mineralization [3]. Despite its adequate properties, some characteristics of MTA have been questioned [4,5]. The consistency of this material is sandy and dry, which makes it difficult to insert into cavities [4]. To improve the handling characteristics of MTA, some authors have evaluated different mixing vehicles, including propylene glycol [4]. Bismuth oxide, present in MTA, has been reported to cause negative interference with MTA [6,7,8] and for this reason, other options for radiopacifiers have also been tested [9,10].
A novel calcium silicate-based cement (CSC) containing zirconium oxide as a radiopacifier and propylene glycol/water in its liquid form was recently developed [10,11]. Zirconium oxide has been tested as a substitute for bismuth oxide due to its adequate radiopacity [10,12] and because it does not interfere with the hydration of CSC [13]. Moreover, propylene glycol associated with distilled water has positive effects on the handling characteristics, flowability, and film thickness of CSCs [4,11].
Sealer 26 (S26; Dentsply, Petrόpolis, RJ, Brazil) is an epoxy resin-based endodontic sealer that contains calcium hydroxide [14]. Calcium hydroxide promotes calcium ion release and alkalinity, which favor tissue repair [15]. S26 has a satisfactory sealing ability for preventing bacterial leakage [16,17]. A thicker consistency of this sealer was suggested for use as a retrograde filling material [17]. After testing, an adequate biological response was found, and S26 showed similar results to those of MTA [17].
Ultrasonic energy has been used to improve the flow of various materials within root canals [18,19,20,21]. Ultrasonic activation (US) of an endodontic sealer promotes greater sealer penetration into the dentinal tubules and improves the sealer/dentin interface [21]. The acoustic microstreaming energy transmitted improves the cleaning ability of irrigating solutions, diffusion of medicaments, and the interfacial adaptation of root canal sealers [18,20,21]. US of retrograde filling materials has previously been tested in MTA [22]. A method of inserting the material into root canals using US was evaluated in comparison with hand condensation [23,24]. Yeung et al. [23] found denser material when MTA was inserted using hand condensation followed by indirect US. The US may have increased penetration into the dentinal tubules and influenced the push-out bond strength.
The aim of the study was to evaluate the effect of US of retrograde filling materials (MTA, S26, and CSC) on adaptation to the dentinal walls and push-out bond strength. The null hypothesis tested was that the US would not improve the adaptation and push-out bond strength of the retrograde filling cements.
MATERIALS AND METHODS
The study was approved by the Ethics Committee of Bauru Dental School, University of São Paulo (080/2011). Sixty extracted maxillary canine teeth with a curvature of less than 5° were selected, as described by Schneider [25]. The coronal portions were sectioned using a 0.3-mm Isomet saw (Buehler, Lake Bluff, IL, USA), and the root canal length was standardized at 15 mm. The working length was established by measuring the penetration of a size 10 K-file (Dentsply Maillefer, Ballaigues, Switzerland) until it reached the apical foramen and then subtracting 1 mm. The root canals were shaped using the Reciproc system (VDW, Munich, Germany) to size R50/0.05 and then irrigated with 2 mL of 2.5% sodium hypochlorite. A final flush of 2 mL of 17% ethylenediaminetetraacetic acid (Biodinâmica, Ibiporã, PR, Brazil) for 3 minutes was used to eliminate the smear layer, and the canals were finally washed with 2 mL of distilled water and dried with paper points (Dentsply Maillefer). The canals were filled with size R50/0.05 (VDW) gutta-percha single cones coated with AH Plus sealer (Dentsply Maillefer). The excess of gutta-percha was removed with a heated instrument and vertically compacted. Filled roots were stored in 100% humidity at 37°C for 48 hours to allow the sealer to set. Then, the specimens were embedded in polyester resin, fixed in an apparatus using the Godiva impression compound (Nova DFL, Rio de Janeiro, RJ, Brazil), and horizontally sectioned at 3 mm from the apex, at an angle of approximately 90° to the long axis of roots, using No. 699 steel burs (KG Sorensen, Cotia, SP, Brazil) under continuous water-cooling.
The specimens were fixed in a device to create the retrograde cavities and to favor parallelism of the dentin walls, according to Vivan et al. [26]. The retrograde cavities were prepared with a 12/90D diamond insert coupled to a piezoelectric ultrasonic device (Piezon master 200, EMS, Nyon, Switzerland) measuring 3 mm in depth and 1.5 mm in diameter, with constant irrigation.
The teeth were divided into 6 groups (n = 10) according to the cement used and whether US was performed. In the S26 group, S26 alone was used, while in the S26 US group, S26 was used with US. Likewise, in the MTA group, white MTA (Angelus, Londrina, PR, Brazil) alone was used, and in the MTA US group, white MTA (Angelus) was ultrasonically activated. In the CSC group, only CSC was used, and in the CSC US group, CSC was ultrasonically activated. Before the push-out test, all specimens were analyzed by low-vacuum scanning electron microscopy to verify marginal adaptation.
The CSC was prepared using a proportion of 80% calcium silicate (Portland Cement, Irajazinho, Cimento Rio Branco, Rio de Janeiro, Brazil) to 20% zirconium oxide (Sigma-Aldrich, St. Louis, MO, USA) by weight. The powder-to-liquid ratio used for manipulating CSC was 4:1. The liquid was composed of 80% water and 20% propylene glycol (C3H8O2; Pharmácia Specífica, Bauru, SP, Brazil) by volume. MTA was prepared according to the manufacturer's instructions. S26 was mixed to a denser consistency, with a powder-to-resin ratio of 5:1 [4].
After mixing, the cements were inserted and vertically compacted into retrograde cavities with a condenser (S. S. White, Rio de Janeiro, RJ, Brazil). In the S26 US, MTA US, and CSC US groups, the cement was activated using an ultrasonic unit (Jet-Sonic Four Plus, Gnatus, Ribeirão Preto, SP, Brazil) set to the Endo mode and 30% power for 1 minute (30 seconds in the mesio-distal direction and 30 seconds in the buccal-lingual direction), with a mini Irrisonic tip (Helse Ultrasonic, Santa Rosa do Viterbo, SP, Brazil, Figure 1), which was a prototype of an ultrasonic tip that will be commercially produced. The samples were stored at 37°C and 100% humidity for 72 hours.
Figure 1
Mini Irrisonic tip used for ultrasonic activation (US) of the cements (A). US of the cement on retrograde cavity in the lateral (B) and top views (C). Images depicting agitation of the filling materials.
From the apical portion of the specimens, 3 mm was horizontally sectioned using a 0.3 mm Isomet saw (Buehler) at 200 rpm with continuous water cooling to prevent frictional heat. Then, the surfaces were polished using 200- and 600-grit SiC abrasive paper (Buehler) under running water (Politriz, Arotec, Cotia, SP, Brazil) until 1.5-mm thick sections were obtained (Figure 2A). The thickness of the discs was controlled using a digital micrometer (Starrett Indústria & Comércio Ltda., Itu, SP, Brazil).
Figure 2
(A) Illustrative image of a specimen fixed in polyester resin and horizontally sectioned. (B) Illustrative image of a specimen fixed on the metal apparatus with a vertical force applied in the middle of the canal using the metal point of the test machine.
The specimens were viewed under a low-vacuum scanning electron microscope (SEM; PSEM eXpress, Aspex Corp., Delmont, PA, USA), which did not require metallization of the sample, so that the samples could be reused. Scanning electron micrographs of the material-tooth interface were recorded at ×50 and ×250. The higher magnification was applied to confirm the presence or the absence of gaps. Image analysis was performed using Image J (National Institutes of Health, Bethesda, MD, USA). The images were analyzed for marginal adaptation of the retrograde cement to the dentinal walls. The total perimeter of the canal and the perimeter of gaps at the cement/dentin interface were used to calculate the adaptation of each cement to the dentin. After evaluating the interface, all the specimens were subjected to the push-out test, and the type of failure (adhesive, cohesive, or mixed) was then verified and quantified using a stereomicroscope at ×20 magnification (Stemi 2000C, Carl Zeiss, Jena, Germany) and the AxioVision software (Carls Zeiss).
The samples were subjected to the push-out bond strength test to determine bond strength at the cement/dentin interface. For this purpose, each resin/dentin/root-end filling material disc was placed in a mechanical test machine (EMIC DL 2000, Instron, Barueri, SP, Brazil). A vertical force was applied in the middle of the canals, from the cervical to the apical direction, using the metal point of the test machine (EMIC DL 2000) at a speed of 1 mm/min (Figure 2B). The area (mm2) under load was calculated by the cylinder lateral surface area formula: bonding area = 2πrh, where r is the radius of the preparation circumference, and h is the thickness of the root slice (1.5 mm). The push-out strength value in megapascals (MPa) was calculated by dividing the load (N) by the bonding area (mm2). The maximum force to dislocate the cement from canal was measured in newtons (N). The bond strength was calculated in MPa by dividing the force in N by the area of the canal in mm2 [26].
Statistical analysis was performed using the non-parametric Kruskal-Wallis and Dunn tests for the interface test (p < 0.05), because the Shapiro-Wilk test did not confirm a normal distribution. Analysis of variance and the Tukey's test were used to analyze push-out bond strength, because a normal distribution was confirmed by the D'Agostino-Pearson test (p < 0.05).
RESULTS
The median, minimum, and maximum values of interfacial adaptation are shown in Table 1. There was a statistically significant difference in the comparison of S26 US with MTA (p < 0.05). The cement in the S26 US group presented no gaps at the dentin/cement interface. The other comparisons showed no statistically significant differences (Figure 3). The type of failure observed was predominantly adhesive for all the tested materials.
Table 1
Median, minimum, and maximum values of interfacial adaptation (gaps in dentin/cement interface) and number of samples according to the type of failure
Figure 3
Representative images of interfacial adaptation at ×50 magnification by scanning electron microscope in the (A) mineral trioxide aggregate (MTA), (B) MTA/ultrasonic activation (US), (C) calcium silicate-based cement (CSC), (D) CSC/US, (E) Sealer 26 (S26), and (F) S26/US groups. The white arrows indicate the presence of interfacial gaps.
The mean and standard deviation of the push-out bond strength of the tested cements are presented in Table 2. US significantly improved the bond strength of all the tested cements (p < 0.05). Comparisons of the cements without US showed similar push-out bond strengths among them.
Table 2
Push-out bond strength of the tested cements to dentin
| Group | Bond strength (MPa) |
|---|---|
| S26 | 2.264 ± 0.973a |
| S26 US | 4.072 ± 1.103b |
| MTA | 1.770 ± 1.114a |
| MTA US | 3.208 ± 0.674b |
| CSC | 2.241 ± 0.673a |
| CSC US | 4.018 ± 1.113b |
DISCUSSION
US improved the push-out bond strength of cements at the dentin/cement interface. Interfacial adaptation was significantly altered only in the comparison between the S26 US and MTA groups (p < 0.05). Thus, the null hypothesis was partially rejected. The push-out bond strength analysis, when only the cements without US were compared, showed no statistically significant difference; this was also the case when only the cements with US were compared. This suggests that the greatest influence on the push-out bond strength was the use of US, not the type of cement used.
The use of ultrasound has been proposed for various endodontic treatment procedures, from the agitation of irrigants to the activation of root canal sealers [18,19,20,21,27,28]. Promising results were found for improvements in the intratubular penetration of sealers [21]. We tested whether agitation of MTA during its insertion increased its adaptation to the root canal walls. High levels of cement adaptation at the dentin/cement interface favors sealing, thereby preventing bacterial leakage [29,30]. Previous studies have tested the US of MTA and obtained good results in terms of solubility, density, and sealing capacity [23,24,28]. Aminoshariae et al. [22] used a different methodology that applied US as a cement placement method, and not as a complement to the hand condensation method. In the present investigation, the cements were activated after being previously inserted by means of hand condensation, as previously described [23]. This method resulted in a denser material than was achieved with simple hand condensation [23]. Those results are in accordance with the results of the present study, in which push-out bond strength was enhanced with the use of US. This suggests that the density might have increased the push-out bond strength of the materials tested.
A CSC containing zirconium oxide as a radiopacifier was recently developed [10,11]. This material was previously suggested as a sealer with a powder-to-liquid ratio of 0.3 [11]. In the present study, for manipulating the CSC, a powder-to-liquid ratio of 4:1 was used to obtain a denser consistency for retrograde fillings. The formulation of this cement contained liquid propylene glycol, as previously described [4]. The addition of 20% propylene glycol to distilled water improved the handling characteristics of MTA, enhanced the bond to dentinal walls, and did not interfere with its biological properties [4,8]. In the present study, no differences in interfacial adaptation or push-out bond strength were found among CSC, MTA, and S26.
The interfacial adaptation values of the cements to the root canal walls were higher in the groups in which US was applied; however, no statistically significant differences were found when the values were compared with those of the same cement, either ultrasonically activated or not. The only statistically significant difference was found between the S26 US and MTA groups (p < 0.05). In this case, in addition to ultrasonic agitation, the composition of the materials could have influenced the results. S26 is a resinous material that has been reported to show high flowability [14], while MTA is based on tricalcium silicate, which is known for its low flow rate [4]. Thus, in addition to S26 having a higher flow rate than MTA, when treated with ultrasonic agitation, this flow rate was even higher, thereby improving the penetration of the cement and its interfacial adaptation.
The type of failure observed was predominantly adhesive. This suggests that the bond of these materials to dentin was not effective. For MTA and CSC, this was expected, as these materials were hydraulic and not resinous. For S26, the remnant smear layer present on the dentin surface before cement application might have obstructed the tubules, preventing adequate penetration.
In this study, the push-out bond strength increased with the US of the cements (p < 0.05). High interface bond strength to the canal walls was found for all the ultrasonically activated groups. This property is crucial for preventing cement displacement from the cavity and subsequent gaps at the interface. A previous report showed that US improved the penetration of root canal sealers into the dentinal tubules, resulting in superior interfacial adaptation [21].
Taking into account the limitations of this study, in which the samples were subjected to humidity, whereas clinically the retrograde cavity would be exposed to blood, further studies are needed to demonstrate whether blood interferes with interfacial adaptation and push-out bond strength. Additional studies are needed to determine whether the effect of US on improving the push-out bond strength of cements is related to changes in their structures or limited only to their increased adaptation to the canal walls.
CONCLUSIONS
The US of retrograde filling cements favored higher bond strength to the dentin walls of the root-end filling materials tested and may be a protocol suitable for clinical use.
-
Conflict of Interest: No potential conflict of interest relevant to this article was reported.
-
Author Contributions:
Conceptualization: Vivan RR, Duarte MAH.
Data curation: Alcalde MP, Fernandes SL, Rosseto MB.
Formal analysis: Alcalde MP, Fernandes SL, Rosseto MB.
Funding acquisition: Vivan RR, Duarte MAH.
Investigation: Alcalde MP, Fernandes SL, Rosseto MB.
Methodology: Alcalde MP, Fernandes SL, Rosseto MB.
Project administration: Vivan RR, Duarte MAH.
Resources: Vivan RR, Duarte MAH.
Software: Marciano MA, Duque JA.
Supervision: Vivan RR, Duarte MAH.
Validation: Vivan RR, Duarte MAH.
Visualization: Marciano MA, Duque JA.
Writing - original draft: Marciano MA, Duque JA.
Writing - review & editing: Marciano MA, Duque JA.
ARTICLE INFORMATION
- 1. Friedman S, Rotstein I, Koren L, Trope M. Dye leakage in retrofilled dog teeth and its correlation with radiographic healing. J Endod 1991;17:392-395. ArticlePubMed
- 2. Lee SJ, Monsef M, Torabinejad M. Sealing ability of a mineral trioxide aggregate for repair of lateral root perforations. J Endod 1993;19:541-544. ArticlePubMed
- 3. Maroto M, Barbería E, Planells P, García Godoy F. Dentin bridge formation after mineral trioxide aggregate (MTA) pulpotomies in primary teeth. Am J Dent 2005;18:151-154. PubMed
- 4. Duarte MAH, Alves de Aguiar K, Zeferino MA, Vivan RR, Ordinola-Zapata R, Tanomaru-Filho M. Evaluation of the propylene glycol association on some physical and chemical properties of mineral trioxide aggregate. Int Endod J 2012;45:565-570. ArticlePubMed
- 5. Salem Milani A, Froughreyhani M, Charchi Aghdam S, Pournaghiazar F, Asghari Jafarabadi M. Mixing with propylene glycol enhances the bond strength of mineral trioxide aggregate to dentin. J Endod 2013;39:1452-1455. ArticlePubMed
- 6. Camilleri J. Hydration mechanisms of mineral trioxide aggregate. Int Endod J 2007;40:462-470. ArticlePubMed
- 7. Coomaraswamy KS, Lumley PJ, Hofmann MP. Effect of bismuth oxide radioopacifier content on the material properties of an endodontic Portland cement-based (MTA-like) system. J Endod 2007;33:295-298. ArticlePubMed
- 8. Marciano MA, Costa RM, Camilleri J, Mondelli RF, Guimarães BM, Duarte MAH. Assessment of color stability of white mineral trioxide aggregate angelus and bismuth oxide in contact with tooth structure. J Endod 2014;40:1235-1240. PubMed
- 9. Cutajar A, Mallia B, Abela S, Camilleri J. Replacement of radiopacifier in mineral trioxide aggregate; characterization and determination of physical properties. Dent Mater 2011;27:879-891. ArticlePubMed
- 10. Duarte MAH, de Oliveira El Kadre GD, Vivan RR, Guerreiro Tanomaru JM, Tanomaru Filho M, de Moraes IG. Radiopacity of portland cement associated with different radiopacifying agents. J Endod 2009;35:737-740. ArticlePubMed
- 11. Marciano MA, Duarte MAH, Camilleri J. Calcium silicate-based sealers: Assessment of physicochemical properties, porosity and hydration. Dent Mater 2016;32:e30-e40. ArticlePubMed
- 12. Camilleri J, Grech L, Galea K, Keir D, Fenech M, Formosa L, Damidot D, Mallia B. Porosity and root dentine to material interface assessment of calcium silicate-based root-end filling materials. Clin Oral Investig 2014;18:1437-1446.PubMed
- 13. Camilleri J, Sorrentino F, Damidot D. Investigation of the hydration and bioactivity of radiopacified tricalcium silicate cement, Biodentine and MTA Angelus. Dent Mater 2013;29:580-593. ArticlePubMed
- 14. Bernardes RA, de Amorim Campelo A, Junior DS, Pereira LO, Duarte MAH, Moraes IG, Bramante CM. Evaluation of the flow rate of 3 endodontic sealers: Sealer 26, AH Plus, and MTA obtura. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:e47-e49.Article
- 15. Duarte MAH, Demarchi AC, Giaxa MH, Kuga MC, Fraga SC, de Souza LC. Evaluation of pH and calcium ion release of three root canal sealers. J Endod 2000;26:389-390. ArticlePubMed
- 16. Siqueira JF, Roças IN, Valois CR. Apical sealing ability of five endodontic sealers. Aust Endod J 2001;27:33-35. PubMed
- 17. Tanomaru-Filho M, Luis MR, Leonardo MR, Tanomaru JM, Silva LA. Evaluation of periapical repair following retrograde filling with different root-end filling materials in dog teeth with periapical lesions. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;102:127-132. ArticlePubMed
- 18. Harrison AJ, Chivatxaranukul P, Parashos P, Messer HH. The effect of ultrasonically activated irrigation on reduction of Enterococcus faecalis in experimentally infected root canals. Int Endod J 2010;43:968-977. ArticlePubMed
- 19. Huffaker SK, Safavi K, Spangberg LS, Kaufman B. Influence of a passive sonic irrigation system on the elimination of bacteria from root canal systems: a clinical study. J Endod 2010;36:1315-1318. ArticlePubMed
- 20. Duarte MAH, Balan NV, Zeferino MA, Vivan RR, Morais CA, Tanomaru-Filho M, Ordinola-Zapata R, Moraes IG. Effect of ultrasonic activation on pH and calcium released by calcium hydroxide pastes in simulated external root resorption. J Endod 2012;38:834-837. ArticlePubMed
- 21. Guimarães BM, Amoroso-Silva PA, Alcalde MP, Marciano MA, de Andrade FB, Duarte MAH. Influence of ultrasonic activation of 4 root canal sealer on the filling quality. J Endod 2014;40:964-968. PubMed
- 22. Aminoshariae A, Hartwell GR, Moon PC. Placement of mineral trioxide aggregate using two different techniques. J Endod 2003;29:679-682. ArticlePubMed
- 23. Yeung P, Liewehr FR, Moon PC. A quantitative comparison of the fill density of MTA produced by two placement techniques. J Endod 2006;32:456-459. ArticlePubMed
- 24. Bernabé PF, Gomes-Filho JE, Bernabé DG, Nery MJ, Otoboni-Filho JA, Dezan E Jr, Cintra LT. Sealing ability of MTA used as a root end filling material: effect of the sonic and ultrasonic condensation. Braz Dent J 2013;24:107-110. PubMed
- 25. Schneider SW. A comparison of canal preparations in straight and curved root canals. Oral Surg Oral Med Oral Pathol 1971;32:271-275. ArticlePubMed
- 26. Vivan RR, Guerreiro-Tanomaru JM, Bosso-Martelo R, Costa BC, Duarte MAH, Tanomaru-Filho M. Push-out bond strength of root-end filling materials. Braz Dent J 2016;27:332-335. ArticlePubMed
- 27. Basturk FB, Nekoofar MH, Günday M, Dummer PM. The effect of various mixing and placement techniques on the compressive strength of mineral trioxide aggregate. J Endod 2013;39:111-114. ArticlePubMed
- 28. Duque JA, Fernandes SL, Bubola JP, Duarte MAH, Camilleri J, Marciano MA. The effect of mixing method on tricalcium silicate-based cement. Int Endod J 2018;51:69-78. PubMed
- 29. Xavier CB, Weismann R, de Oliveira MG, Demarco FF, Pozza DH. Root-end filling materials: apical microleakage and marginal adaptation. J Endod 2005;31:539-542. ArticlePubMed
- 30. Maltezos C, Glickman GN, Ezzo P, He J. Comparison of the sealing of Resilon, Pro Root MTA, and Super-EBA as root-end filling materials: a bacterial leakage study. J Endod 2006;32:324-327. ArticlePubMed
REFERENCES
Tables & Figures
REFERENCES
Citations
Citations to this article as recorded by 
ePub Link
Cite
XML DownloadEffect of ultrasonic agitation on push-out bond strength and adaptation of root-end filling materials
Figure 1 Mini Irrisonic tip used for ultrasonic activation (US) of the cements (A). US of the cement on retrograde cavity in the lateral (B) and top views (C). Images depicting agitation of the filling materials.
Figure 2 (A) Illustrative image of a specimen fixed in polyester resin and horizontally sectioned. (B) Illustrative image of a specimen fixed on the metal apparatus with a vertical force applied in the middle of the canal using the metal point of the test machine.
Figure 3 Representative images of interfacial adaptation at ×50 magnification by scanning electron microscope in the (A) mineral trioxide aggregate (MTA), (B) MTA/ultrasonic activation (US), (C) calcium silicate-based cement (CSC), (D) CSC/US, (E) Sealer 26 (S26), and (F) S26/US groups. The white arrows indicate the presence of interfacial gaps.
Figure 1
Figure 2
Figure 3
Effect of ultrasonic agitation on push-out bond strength and adaptation of root-end filling materials
Median, minimum, and maximum values of interfacial adaptation (gaps in dentin/cement interface) and number of samples according to the type of failure
| Group | Gap (µm) | Failure | ||
|---|---|---|---|---|
| Adhesive | Cohesive | Mixed | ||
| MTA | 6.79 (0.00–27.10)a | 7 | 2 | 1 |
| MTA US | 1.90 (0.00–17.34)ab | 8 | 1 | 1 |
| S26 | 1.18 (0.00–8.40)ab | 7 | 1 | 2 |
| S26 US | 0.00 (0.00–4.75)b | 6 | 2 | 2 |
| CSC | 4.66 (0.00–15.08)ab | 7 | 1 | 2 |
| CSC US | 1.15 (0.00–13.04)ab | 8 | 0 | 2 |
Different lowercase superscript letters indicate statistically significant differences between groups (p < 0.05).
MTA, mineral trioxide aggregate; US, ultrasound activation; S26, Sealer 26; CSC, calcium silicate-based cement.
Push-out bond strength of the tested cements to dentin
| Group | Bond strength (MPa) |
|---|---|
| S26 | 2.264 ± 0.973a |
| S26 US | 4.072 ± 1.103b |
| MTA | 1.770 ± 1.114a |
| MTA US | 3.208 ± 0.674b |
| CSC | 2.241 ± 0.673a |
| CSC US | 4.018 ± 1.113b |
Data were presented in means ± standard deviations.
Different lowercase superscript letters represent signifcant differences among the groups (p < 0.05).
S26, Sealer 26; US, ultrasound activation; MTA, mineral trioxide aggregate; CSC, calcium silicate-based cement.
Table 1 Median, minimum, and maximum values of interfacial adaptation (gaps in dentin/cement interface) and number of samples according to the type of failure
Different lowercase superscript letters indicate statistically significant differences between groups (
MTA, mineral trioxide aggregate; US, ultrasound activation; S26, Sealer 26; CSC, calcium silicate-based cement.
Table 2 Push-out bond strength of the tested cements to dentin
Data were presented in means ± standard deviations.
Different lowercase superscript letters represent signifcant differences among the groups (
S26, Sealer 26; US, ultrasound activation; MTA, mineral trioxide aggregate; CSC, calcium silicate-based cement.
