Acessibilidade / Reportar erro

Endodontic cement penetration after removal of calcium hydroxide dressing using XP-endo finisher

Abstract:

We aimed to evaluate the penetration of endodontic cement following the removal of calcium hydroxide (Ca(OH)2) dressing using the XP-endo Finisher in association with different irrigating solutions. Sixty premolars were instrumented and applied with a Ca(OH)2 dressing. To remove Ca(OH)2, the teeth were divided into six groups, each with a different volume of sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA), as well as solution stirring time with XP-endo Finisher (0, 30, and 60 sec). Root canals were filled using the lateral condensation technique. Fluorescein dye was added to the cement for microscopic laser scanning analysis. In the generated images, linear measurements were taken in micrometers, and their averages were calculated. To analyze the perimeter penetration ratio of the cement, the total perimeter of the canal and the segment of the total perimeter of the canal where the endodontic cement penetrated into the dentinal tubules were measured in micrometers. We found that using an XP-endo Finisher in irrigation was more effective than using a needle and syringe during the extension and penetration of endodontic cement. Shaking with XP-endo Finisher with 17% EDTA increased the extent and perimeter of the penetration of the endodontic cement into the dentinal tubules. However, using the XP-endo Finisher with EDTA only was more efficient than using the instrument interchangeably in NaOCl and EDTA. Although XP-endo Finisher contributes to the removal of Ca(OH)2, none of the protocols or instruments used removed all Ca(OH)2 from the root system.

Keywords:
Calcium Hydroxide; Microscopy, Confocal; Edetic Acid; Sodium Hypochlorite; Therapeutic Irrigation

Introduction

A successful root canal treatment depends on appropriate access cavity preparation, as well as proper shaping, appropriate cleaning, and accurate tridimensional sealing of the root canal system.11 Haapasalo M, Endal U, Zandi H, Coil JM. Eradication of endodontic infection by instrumentation and irrigation solutions. Endod Topics. 2005 Aug;10(1):77-102. https://doi.org/10.1111/j.1601-1546.2005.00135.x
https://doi.org/10.1111/j.1601-1546.2005...
However, removing every pathological entity present in the root canal system remains especially challenging.22 Nair PN. On the causes of persistent apical periodontitis: a review. Int Endod J. 2006 Apr;39(4):249-81. https://doi.org/10.1111/j.1365-2591.2006.01099.x
https://doi.org/10.1111/j.1365-2591.2006...

Since mechanical instrumentation and irrigation cannot completely eliminate microbiota,33 Ghoddusi J, Javidi M, Zarrabi MH, Bagheri H. Flare-ups incidence and severity after using calcium hydroxide as intracanal dressing. N Y State Dent J. 2006 Jun-Jul;72(4):24-8.,44 Memon NA, Memon MR, Ali FU, Ane N. Assessment of the interappointment pain by using two different intracanal medicaments. Pak Oral Dent J. 2013 Apr;33(1):145-50. https://doi.org/10.5395/rde.2020.45.e26
https://doi.org/10.5395/rde.2020.45.e26...
an approach for supplementing the disinfecting effects of conventional chemo-mechanical procedures with intracanal medication has been recommended.55 Uzunoglu E, Eymirli A, Uyanik MÖ, Çalt S, Nagas E. Calcium hydroxide dressing residues after different removal techniques affect the accuracy of Root-ZX apex locator. Restor Dent Endod. 2015 Feb;40(1):44-9. https://doi.org/10.5395/rde.2015.40.1.44
https://doi.org/10.5395/rde.2015.40.1.44...
Calcium hydroxide (Ca(OH)2) is considered the most favorable antimicrobial agent33 Ghoddusi J, Javidi M, Zarrabi MH, Bagheri H. Flare-ups incidence and severity after using calcium hydroxide as intracanal dressing. N Y State Dent J. 2006 Jun-Jul;72(4):24-8.,66 Orstavik D. Root canal disinfection: a review of concepts and recent developments. Aust Endod J. 2003 Aug;29(2):70-4. https://doi.org/10.1111/j.1747-4477.2003.tb00515.x
https://doi.org/10.1111/j.1747-4477.2003...

7 Law A, Messer H. An evidence-based analysis of the antibacterial effectiveness of intracanal medicaments. J Endod. 2004 Oct;30(10):689-94. https://doi.org/10.1097/01.DON.0000129959.20011.EE
https://doi.org/10.1097/01.DON.000012995...
-88 Athanassiadis B, Walsh LJ. Aspects of solvent chemistry for calcium hydroxide medicaments. Materials (Basel). 2017 Oct;10(10):1219-27. https://doi.org/10.3390/ma10101219
https://doi.org/10.3390/ma10101219...
and is a universally accepted inter-appointment intracanal medicament because of its biocompatibility, antimicrobial properties, and tissue dissolution ability.99 Khaleel HY, Al-Ashaw AJ, Yang Y, Pang AH, Ma JZ. Quantitative comparison of calcium hydroxide removal by EndoActivator, ultrasonic and ProTaper file agitation techniques: an in vitro study. J Huazhong Univ Sci Technolog Med Sci. 2013 Feb;33(1):142-5. https://doi.org/10.1007/s11596-013-1087-x
https://doi.org/10.1007/s11596-013-1087-...
However, Ca(OH)2 is typically insoluble in most dental vehicles, which in association with the RCS complexity limits its complete removal.1010 Donnermeyer D, Wyrsch H, Bürklein S, Schäfer E. Removal of calcium hydroxide from artificial grooves in straight root canals: sonic activation using EDDY versus passive ultrasonic irrigation and XPendo finisher. J Endod. 2019 Mar;45(3):322-6. https://doi.org/10.1016/j.joen.2018.11.001
https://doi.org/10.1016/j.joen.2018.11.0...
Residues of dental vehicles can also significantly reduce the setting time and flowability of sealers; this increases the risk of void formation between gutta-percha, sealer, and dentin, and impairs its interaction with dentin collagen to limit stable adhesion to the substrate,1010 Donnermeyer D, Wyrsch H, Bürklein S, Schäfer E. Removal of calcium hydroxide from artificial grooves in straight root canals: sonic activation using EDDY versus passive ultrasonic irrigation and XPendo finisher. J Endod. 2019 Mar;45(3):322-6. https://doi.org/10.1016/j.joen.2018.11.001
https://doi.org/10.1016/j.joen.2018.11.0...

11 Alkhudhairy FI, Yaman P, Dennison J, McDonald N, Herrero A, Bin-Shuwaish MS. The effects of different irrigation solutions on the bond strength of cemented fiber posts. Clin Cosmet Investig Dent. 2018 Oct;10:221-30. https://doi.org/10.2147/CCIDE.S155688
https://doi.org/10.2147/CCIDE.S155688...

12 Neelakantan P, Sriraman P, Gutmann JL. Removal of calcium hydroxide intracanal medicament by different irrigants and irrigating techniques: a cone beam computed tomography analysis. Gen Dent. 2017 Nov-Dec;65(6):45-9.

13 Rödig T, Hirschleb M, Zapf A, Hülsmann M. Comparison of ultrasonic irrigation and RinsEndo for the removal of calcium hydroxide and Ledermix paste from root canals. Int Endod J. 2011 Dec;44(12):1155-61. https://doi.org/10.1111/j.1365-2591.2011.01937.x
https://doi.org/10.1111/j.1365-2591.2011...
-1414 Goldberg F, Artaza LP, De S. Influence of calcium hydroxide dressing on the obturation of simulated lateral canals. J Endod. 2002 Feb;28(2):99-101. https://doi.org/10.1097/00004770-200202000-00012
https://doi.org/10.1097/00004770-2002020...
affecting adaptation of the filling material to the root canal walls and influencing the bond strength of dentin.

Ca(OH)2 removal is as crucial as removing the smear layer and debris from the root canal before filling, to better adapt the filling material to the canal walls.1515 Kim SK, Kim YO. Influence of calcium hydroxide intracanal medication on apical seal. Int Endod J. 2002 Jul;35(7):623-8. https://doi.org/10.1046/j.1365-2591.2002.00539.x
https://doi.org/10.1046/j.1365-2591.2002...
RCS complexity makes removal of the Ca(OH)2 dressing, especially in the apical third, more critical when only the conventional syringe irrigation technique and needle are used1313 Rödig T, Hirschleb M, Zapf A, Hülsmann M. Comparison of ultrasonic irrigation and RinsEndo for the removal of calcium hydroxide and Ledermix paste from root canals. Int Endod J. 2011 Dec;44(12):1155-61. https://doi.org/10.1111/j.1365-2591.2011.01937.x
https://doi.org/10.1111/j.1365-2591.2011...
,1616 Marques-da-Silva B, Alberton CS, Tomazinho FS, Gabardo MC, Duarte MA, Vivan RR, et al. Effectiveness of five instruments when removing calcium hydroxide paste from simulated internal root resorption cavities in extracted maxillary central incisors. Int Endod J. 2020 Mar;53(3):366-75. https://doi.org/10.1111/iej.13223
https://doi.org/10.1111/iej.13223...
.

Ca(OH)2 may be eliminated by the mechanical action of instruments in the reaming motion1717 Taşdemir T, Celik D, Er K, Yildirim T, Ceyhanli KT, Yeşilyurt C. Efficacy of several techniques for the removal of calcium hydroxide medicament from root canals. Int Endod J. 2011 Jun;44(6):505-9. https://doi.org/10.1111/j.1365-2591.2011.01854.x
https://doi.org/10.1111/j.1365-2591.2011...
and the chemical and physical action of irrigants.1818 Balvedi RP, Versiani MA, Manna FF, Biffi JC. A comparison of two techniques for the removal of calcium hydroxide from root canals. Int Endod J. 2010 Sep;43(9):763-8. https://doi.org/10.1111/j.1365-2591.2010.01718.x PMID:20546045
https://doi.org/10.1111/j.1365-2591.2010...
Several techniques have been proposed to remove the Ca(OH)2 dressing from the root canal system, including the use of endodontic hand files,1919 Lambrianidis T, Kosti E, Boutsioukis C, Mazinis M. Int Endod J. Removal efficacy of various calcium hydroxide/chlorhexidine medicaments from the root canal. 2006 Jan;39(1):55-61. https://doi.org/10.1111/j.1365-2591.2005.01049.x
https://doi.org/10.1111/j.1365-2591.2005...
sonic activation,2020 Wiseman A, Cox TC, Paranjpe A, Flake NM, Cohenca N, Johnson JD. Efficacy of sonic and ultrasonic activation for removal of calcium hydroxide from mesial canals of mandibular molars: a microtomographic study. J Endod. 2011 Feb;37(2):235-8. https://doi.org/10.1016/j.joen.2010.11.019
https://doi.org/10.1016/j.joen.2010.11.0...
passive ultrasonic irrigation (PUI),2121 van der Sluis LW, Wu MK, Wesselink PR. The evaluation of removal of calcium hydroxide paste from an artificial standardized groove in the apical root canal using different irrigation methodologies. Int Endod J. 2007 Jan;40(1):52-7. https://doi.org/10.1111/j.1365-2591.2006.01182.x
https://doi.org/10.1111/j.1365-2591.2006...
and nickel-titanium (NiTi) rotary instruments.2222 Kenee DM, Allemang JD, Johnson JD, Hellstein J, Nichol BK. A quantitative assessment of efficacy of various calcium hydroxide removal techniques. J Endod. 2006 Jun;32(6):563-5. https://doi.org/10.1016/j.joen.2005.10.065
https://doi.org/10.1016/j.joen.2005.10.0...
,2323 Soares JA, Leonardo MR, Silva LA, Tanomaru Filho M, Ito IY. Effect of rotary instrumentation and of the association of calcium hydroxide and chlorhexidine on the antisepsis of the root canal system in dogs. Braz Oral Res. 2006 Apr-Jun;20(2):120-6. https://doi.org/10.1590/S1806-83242006000200006
https://doi.org/10.1590/S1806-8324200600...
The most commonly described method for Ca(OH)2 removal is instrumentation along with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) irrigant solutions combined with a “master apical file” at working length (WL).2424 Salgado RJ, Moura-Netto C, Yamazaki AK, Cardoso LN, de Moura AA, Prokopowitsch I. Comparison of different irrigants on calcium hydroxide medication removal: microscopic cleanliness evaluation. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Apr;107(4):580-4. https://doi.org/10.1016/j.tripleo.2008.12.008
https://doi.org/10.1016/j.tripleo.2008.1...
,2525 Lambrianidis T, Margelos J, Beltes P. Removal efficiency of calcium hydroxide dressing from the root canal. J Endod. 1999 Feb;25(2):85-8. https://doi.org/10.1016/S0099-2399(99)80002-8
https://doi.org/10.1016/S0099-2399(99)80...

Although various systems for Ca(OH)2 dressing removal have been cited in the literature, none have removed all of the Ca(OH)2.2626 Alturaiki S, Lamphon H, Edrees H, Ahlquist M. Efficacy of 3 different irrigation systems on removal of calcium hydroxide from the root canal: a scanning electron microscopic study. J Endod. 2015 Jan;41(1):97-101. https://doi.org/10.1016/j.joen.2014.07.033
https://doi.org/10.1016/j.joen.2014.07.0...
Studies on different Ca(OH)2 removal protocols have also shown residual volumes of 3%–20%, mainly in the apical region.2222 Kenee DM, Allemang JD, Johnson JD, Hellstein J, Nichol BK. A quantitative assessment of efficacy of various calcium hydroxide removal techniques. J Endod. 2006 Jun;32(6):563-5. https://doi.org/10.1016/j.joen.2005.10.065
https://doi.org/10.1016/j.joen.2005.10.0...

The XP-endo Finisher (FKG Dentaire, La Chaux de Fonds, Switzerland) is a rotary root canal instrument available in the market. It is a universal NiTi-based instrument measuring ISO 25 in diameter with zero taper, and it is indicated for use in instrumentation of canals with complex morphology and inaccessible areas. This file is highly flexible and can be expanded. The new technology behind XP-endo Finisher file manufacturing is based on the shape-memory principles of the NiTi alloy. These features help in dentine preservation and enable the file to access areas that are inaccessible to conventional instruments. In addition, the medication inside the canal and residual obturation material during retreatment can be removed.2727 Denna J, Shafie LA, Alsofi L, Al-Habib M, AlShwaimi E. Efficacy of the rotary instrument xp-endo finisher in the removal of calcium hydroxide intracanal medicament in combination with different irrigation techniques: a microtomographic study. Materials (Basel). 2020 May;13(10):2222-33. https://doi.org/10.3390/ma13102222
https://doi.org/10.3390/ma13102222...

This study aimed to evaluate the penetration of endodontic cement following the removal of Ca(OH)2 dressing with XP-endo Finisher in combination with different irrigating solutions.

Methodology

Sample Selection

Sixty single-rooted premolar teeth were selected after the study was approved by the research ethics committee (PUC Minas; no. 59289716.0.0000.5137). By evaluating two periapical radiographs (Kodak 2200, 70 kV, phosphor photoactive plate) of each tooth in the vestibular-palatal and mesiodistal directions, teeth with more than one canal, incomplete rhizogenesis, resorption (i.e., internal and external), fracture lines, root curvature, or instrumented or filled canals were excluded. The selected teeth were randomly distributed into six groups, each containing 10 specimens, which were stored in distilled water and 2.5% NaOCl, in a proportion of 10:1.

Criteria for root standardization and instrumentation

All the procedures were performed by a single endodontic specialist. Using a carborundum disc (SS White Dental Articles, Rio de Janeiro, Brazil), the crowns were removed at the amelo–cementitious junction and the roots were cut at the cervical portion, standardizing the total length to 14.0 mm.

Initially, canal patency length was visually determined by introducing a #10 K file (Maillefer, Ballaigues, Switzerland) until reaching the apical foramen, and the specimens were fixed in a lathe to facilitate the chemical–mechanical preparation. The teeth were instrumented with ProTaper Next (Dentsply, Maillefer, Ballaigues, Switzerland) files to the X5 file (0.5 mm) from the apex (WL).

For canal irrigation, a 27-gauge hypodermic needle (Ultradent Products, South Jordan, USA) coupled with a 5-mL syringe was used. The canals were irrigated at each instrument exchange with 1 mL of 2.5% NaOCl solution and a size-10 K patency file (Maillefer, Ballaigues, Switzerland). After instrumentation, the canals were irrigated with 1 mL of 17% EDTA solution and 1 mL of 2.5% NaOCl solution to remove the smear layer. The canals were then dried with absorbent paper tips (ProTaper, Maillefer, Ballaigues, Switzerland).2828 Ordinola-Zapata R, Bramante CM, Graeff MS, Carpio Perochena A, Vivan RR, Camargo EJ, et al. Depth and percentage of penetration of endodontic sealers into dentinal tubules after root canal obturation using a lateral compaction technique: a confocal laser scanning microscopy study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Sep;108(3):450-7. https://doi.org/10.1016/j.tripleo.2009.04.024
https://doi.org/10.1016/j.tripleo.2009.0...

Calcium hydroxide P.A. (Biodynamic, Ibiporã, Brazil) intracanal dressing was handled with distilled water according to the manufacturer's recommendations. Using a thin-walled drill (Dentsply, Maillefer, Ballaigues, Switzerland), the Ca(OH)2 slurry was drawn into the root canals, after which the teeth were sealed with temporary cement (Coltosol, Vigodente SA, Bom Sucesso, Brazil). The dressing was maintained for 14 days, and the teeth were stored in an oven at 37 °C under suitable conditions of 90%–95% humidity.

Removal of the intracanal dressing

The Ca(OH)2 dressing was removed from the canals differently in each experimental group (Table 1). XP-endo Finisher (FKG Dentaire, La Chaux de Fonds, Switzerland) was used with an X Smart endodontic motor (Dentsply Sirona, Ballaigues, Switzerland) at a speed of 800 rpm and torque of 1 N.cm.2929 Hamdan R, Michetti J, Pinchon D, Diemer F, Georgelin-Gurgel M. The XP-Endo Finisher for the removal of calcium hydroxide paste from root canals and from the apical third. J Clin Exp Dent. 2017 Jul;9(7):e855-60. https://doi.org/10.4317/jced.53962
https://doi.org/10.4317/jced.53962...
,3030 Keskin C, Sariyilmaz E, Sariyilmaz Ö. Efficacy of XP-endo finisher file in removing calcium hydroxide from simulated internal resorption cavity. J Endod. 2017 Jan;43(1):126-30. https://doi.org/10.1016/j.joen.2016.09.009
https://doi.org/10.1016/j.joen.2016.09.0...
,3131 Kfir A, Blau-Venezia N, Goldberger T, Abramovitz I, Wigler R. Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove. Aust Endod J. 2018 Apr;44(1):26-31. https://doi.org/10.1111/aej.12204
https://doi.org/10.1111/aej.12204...

Table 1
Experimental groups

All solutions used were heated to 37°C following the method of Hamdan et al.2929 Hamdan R, Michetti J, Pinchon D, Diemer F, Georgelin-Gurgel M. The XP-Endo Finisher for the removal of calcium hydroxide paste from root canals and from the apical third. J Clin Exp Dent. 2017 Jul;9(7):e855-60. https://doi.org/10.4317/jced.53962
https://doi.org/10.4317/jced.53962...
and Kfir et al.3131 Kfir A, Blau-Venezia N, Goldberger T, Abramovitz I, Wigler R. Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove. Aust Endod J. 2018 Apr;44(1):26-31. https://doi.org/10.1111/aej.12204
https://doi.org/10.1111/aej.12204...
The lateral condensation technique with endodontic cement (AH Plus, Dentsply Detrey GmbH, Konstanz, Germany) was used to fill the canals after drying with an absorbent paper cone. Fluorescein dye (Sigma-Aldrich, St. Louis, MO, USA) was added to the cement for microscopic laser scanning analysis. The teeth were carefully sealed with Coltosol (Vigodente SA, Bom Sucesso, Brazil). The samples were stored at 37 °C under 90%– 95% humidity for 48 h.

Analysis of teeth with confocal laser scanning microscopy

After 48 h, the teeth were cross-sectioned into 0.3-mm thick pieces using an Isomet™ 1000 precision cutter (Buehler Ltd., Illinois, USA) at 200 rpm with the continuous use of water under refrigeration at 3, 6, and 9 mm of the root apex.

The dentin segments were inserted into glass slides polished with progressive granulation sieves 300, 600, and 1,200 with the respective identification of the group and number of specimens analyzed. The slides were then examined using a TCS–SPE confocal laser scanning microscope (CLSM; Leica, Mannheim, Germany). The images were processed in a single focal plane of 512 × 512 pixels at 10× magnification, and excitation was performed with a 488-nm diode laser for fluorescein, following the method of Ordinola-Zapata et al.2828 Ordinola-Zapata R, Bramante CM, Graeff MS, Carpio Perochena A, Vivan RR, Camargo EJ, et al. Depth and percentage of penetration of endodontic sealers into dentinal tubules after root canal obturation using a lateral compaction technique: a confocal laser scanning microscopy study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Sep;108(3):450-7. https://doi.org/10.1016/j.tripleo.2009.04.024
https://doi.org/10.1016/j.tripleo.2009.0...
and Silva et al.3232 Silva RV, Silveira FF, Horta MC, Duarte MA, Cavenago BC, Morais IG, et al. Filling effectiveness and dentinal penetration of endodontic sealers: a stereo and confocal laser scanning microscopy study. Braz Dent J. 2015 Oct;26(5):541-6. https://doi.org/10.1590/0103-6440201300138
https://doi.org/10.1590/0103-64402013001...

Data tabulation

The images obtained by CLSM were stored in a USB drive. For the analysis and tabulation of data, ImageJ (National Institutes of Health, Bethesda, USA) was used. In the generated images, four points were standardized (vestibular, lingual, mesial, and distal) in each image based on the method proposed by Silva et al.,3232 Silva RV, Silveira FF, Horta MC, Duarte MA, Cavenago BC, Morais IG, et al. Filling effectiveness and dentinal penetration of endodontic sealers: a stereo and confocal laser scanning microscopy study. Braz Dent J. 2015 Oct;26(5):541-6. https://doi.org/10.1590/0103-6440201300138
https://doi.org/10.1590/0103-64402013001...
Bitter et al.,3333 Bitter K, Paris S, Martus P, Schartner R, Kielbassa AM. A Confocal Laser Scanning Microscope investigation of different dental adhesives bonded to root canal dentine. Int Endod J. 2004 Dec;37(12):840-8. https://doi.org/10.1111/j.1365-2591.2004.00888.x
https://doi.org/10.1111/j.1365-2591.2004...
and Gharib et al.3434 Gharib SR, Tordik PA, Imamura GM, Baginski TA, Goodell GG. A confocal laser scanning microscope investigation of the epiphany obturation system. J Endod. 2007 Aug;33(8):957-61. https://doi.org/10.1016/j.joen.2007.03.011
https://doi.org/10.1016/j.joen.2007.03.0...
Linear measurements were then taken in micrometers, and their averages were calculated (Figure 1). To analyze the perimeter penetration ratio of the cement, the total perimeter of the canal and the segment where the endodontic cement penetrated into the dentinal tubules were measured in micrometers.3333 Bitter K, Paris S, Martus P, Schartner R, Kielbassa AM. A Confocal Laser Scanning Microscope investigation of different dental adhesives bonded to root canal dentine. Int Endod J. 2004 Dec;37(12):840-8. https://doi.org/10.1111/j.1365-2591.2004.00888.x
https://doi.org/10.1111/j.1365-2591.2004...
,3434 Gharib SR, Tordik PA, Imamura GM, Baginski TA, Goodell GG. A confocal laser scanning microscope investigation of the epiphany obturation system. J Endod. 2007 Aug;33(8):957-61. https://doi.org/10.1016/j.joen.2007.03.011
https://doi.org/10.1016/j.joen.2007.03.0...
Subsequently, the penetration perimeter value was divided by the total perimeter of the canal to obtain the penetration perimeter ratio (Figure 2). After calculation, all measurements were transferred to a Microsoft Office Excel 2010 worksheet (Microsoft Corporation, Redmond, USA), in which they were tabulated and prepared for statistical analysis.

Figure 1
All teeth had their image recorded in the confocal laser scanning microscope with four standardized points (line blue) for linear gauging.
Figure 2
Image recorded in the confocal laser scanning microscope with penetration perimeter (red line).

Statistical analysis

The data were subjected to D'Agostino–Pearson's normality test, which showed non-normal distribution. Data were initially analyzed using descriptive statistics, including the median, minimum, and maximum.

The Friedman test followed by Dunn's post hoc test for the comparison of pairs was used to evaluate differences in cement penetration (i.e., linear measurements and penetration perimeter ratio) between the apical third, middle third, and cervical third. Both tests were performed separately for each group.

The Kruskal–Wallis test followed by Dunn's post hoc test for the comparison of pairs was then used to evaluate differences in cement penetration (i.e., linear measurements and penetration perimeter ratio) between the six groups. The tests were performed separately for all thirds, apical third, middle third, and cervical third.

All analyses were performed using GraphPad Prism (GraphPad Software, San Diego, USA).

Results

Once the cement penetration was assessed by linear measurements, when the thirds were compared within the same experimental group, a statistical difference was observed only in the G4 between the apical third (3 mm from the root apex) and the cervical third (9 mm from the root apex), with the latter showing more penetration of endodontic cement. When the experimental groups were compared independently in each third, for all thirds grouped, the compared pairs G1-G3, G2-G3, G2-G5, G3-G4, G3-G5, and G3-G6 showed statistically significant differences, with G3 showing the highest value. In both the middle third (6 mm from the root apex) and cervical third (9 mm from the root apex), the compared pairs G2-G3 and G2-G4 showed statistically significant differences, with G2 showing the smallest values. In the apical third, no differences were observed between the experimental groups (Table 2).

Table 2
Cement penetration assessed by linear measurements (median, minimum, maximum, and comparisons)

In terms of differences in cement penetration according to the penetration perimeter ratio, when the thirds were compared within the same group, a statistical difference was found only in G4 group between the apical third (3 mm from the root apex) and cervical third (9 mm from the root apex), with the latter showing the highest penetration perimeter ratio. When the experimental groups were compared independently in each third, for all thirds grouped, only the compared pair G2-G4 showed a statistically significant difference, with G4 showing a higher value. No differences were observed between the experimental groups in the apical third, middle third, and cervical thirds (Table 3).

Table 3
Cement penetration assessed by penetration perimeter ratio (median, minimum, maximum, and comparisons)

Discussion

To avoid negative interactions between the obturator material and the intracanal dressing and to maximize the adaptation of the sealant to the root walls, the temporary medication must be removed completely before filling the root canal. However, root canal morphology and its complexities can affect this process. Numerous studies have suggested attempts for removing Ca(OH)2 from the root canal walls.2424 Salgado RJ, Moura-Netto C, Yamazaki AK, Cardoso LN, de Moura AA, Prokopowitsch I. Comparison of different irrigants on calcium hydroxide medication removal: microscopic cleanliness evaluation. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Apr;107(4):580-4. https://doi.org/10.1016/j.tripleo.2008.12.008
https://doi.org/10.1016/j.tripleo.2008.1...
,2626 Alturaiki S, Lamphon H, Edrees H, Ahlquist M. Efficacy of 3 different irrigation systems on removal of calcium hydroxide from the root canal: a scanning electron microscopic study. J Endod. 2015 Jan;41(1):97-101. https://doi.org/10.1016/j.joen.2014.07.033
https://doi.org/10.1016/j.joen.2014.07.0...
,3535 Berkhoff JA, Chen PB, Teixeira FB, Diogenes A. Evaluation of triple antibiotic paste removal by different irrigation procedures. J Endod. 2014 Aug;40(8):1172-7. https://doi.org/10.1016/j.joen.2013.12.027
https://doi.org/10.1016/j.joen.2013.12.0...
However, the current status of Ca(OH)2 removal remains uncertain, as its removal has been difficult and incomplete.3636 Chawla A, Kumar V. Evaluating the efficacy of different techniques and irrigation solutions for removal of calcium hydroxide from the root canal system: A scanning electron microscope study. J Conserv Dent. 2018 Jul-Aug;21(4):394-400. https://doi.org/10.4103/JCD.JCD_246_17
https://doi.org/10.4103/JCD.JCD_246_17...

The present study used CLSM to analyze materials marked with fluorescein to show the extent and perimeter of penetration of endodontic cement into the root canals after removal of the Ca(OH)2 dressing with XP-endo Finisher, associated with NaOCl and EDTA.2828 Ordinola-Zapata R, Bramante CM, Graeff MS, Carpio Perochena A, Vivan RR, Camargo EJ, et al. Depth and percentage of penetration of endodontic sealers into dentinal tubules after root canal obturation using a lateral compaction technique: a confocal laser scanning microscopy study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Sep;108(3):450-7. https://doi.org/10.1016/j.tripleo.2009.04.024
https://doi.org/10.1016/j.tripleo.2009.0...

Labeling materials detected by CLSM, as used in this study, seems to be an adequate and economical way of assessing the penetration of the materials present inside the dentinal tubules.2929 Hamdan R, Michetti J, Pinchon D, Diemer F, Georgelin-Gurgel M. The XP-Endo Finisher for the removal of calcium hydroxide paste from root canals and from the apical third. J Clin Exp Dent. 2017 Jul;9(7):e855-60. https://doi.org/10.4317/jced.53962
https://doi.org/10.4317/jced.53962...
,3737 Kok D, Rosa RA, Barreto MS, Busanello FH, Santini MF, Pereira JR, et al. Penetrability of AH plus and MTA fillapex after endodontic treatment and retreatment: a confocal laser scanning microscopy study. Microsc Res Tech. 2014. June;77(6):467-71. https://doi.org/10.1002/jemt.22371
https://doi.org/10.1002/jemt.22371...
,3838 Piai GG, Duarte MA, Nascimento AL, Rosa RA, Só MV, Vivan RR. Penetrability of a new endodontic sealer: A confocal laser scanning microscopy evaluation. Microsc Res Tech. 2018 Nov;81(11):1246-9. https://doi.org/10.1002/jemt.23129
https://doi.org/10.1002/jemt.23129...

CLSM has several advantages over scanning electron microscopy (SEM), including reliable identification of marked materials and simpler sample preparation in the absence of prior processing, which allows observation as close to normal conditions as possible and minimizes artifact production.3939 Van Meerbeek B, Vargas M, Inoue S, Yoshida Y, Perdigão J, Lambrechts P, et al.; Microscopy investigations. Microscopy investigations. Techniques, results, limitations. Am J Dent. 2000 Nov;13(Spec No):3D-18D.

Regarding the removal of the Ca(OH)2 dressing and the consequent endodontic cement penetration in the tubules, in this study, XP-endo Finisher promoted greater penetration of the endodontic cement compared with conventional irrigation with needle and syringe, which suggests its greater efficiency in removing calcium hydroxide and confirms previous results.3030 Keskin C, Sariyilmaz E, Sariyilmaz Ö. Efficacy of XP-endo finisher file in removing calcium hydroxide from simulated internal resorption cavity. J Endod. 2017 Jan;43(1):126-30. https://doi.org/10.1016/j.joen.2016.09.009
https://doi.org/10.1016/j.joen.2016.09.0...
,3131 Kfir A, Blau-Venezia N, Goldberger T, Abramovitz I, Wigler R. Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove. Aust Endod J. 2018 Apr;44(1):26-31. https://doi.org/10.1111/aej.12204
https://doi.org/10.1111/aej.12204...
,4040 Wigler R, Dvir R, Weisman A, Matalon S, Kfir A. Efficacy of XP-endo finisher files in the removal of calcium hydroxide paste from artificial standardized grooves in the apical third of oval root canals. Int Endod J. 2017 Jul;50(7):700-5. https://doi.org/10.1111/iej.12668
https://doi.org/10.1111/iej.12668...

A similar study compared the efficacy of Xp-endo Finisher and PUI in removing Ca(OH)2 paste from the root canals and the apical third, and the results showed superiority in removing the dressing by P-Endo® Finisher when compared to PUI.2929 Hamdan R, Michetti J, Pinchon D, Diemer F, Georgelin-Gurgel M. The XP-Endo Finisher for the removal of calcium hydroxide paste from root canals and from the apical third. J Clin Exp Dent. 2017 Jul;9(7):e855-60. https://doi.org/10.4317/jced.53962
https://doi.org/10.4317/jced.53962...
In parallel, Gokturk et al.4141 Gokturk H, Ozkocak I, Buyukgebiz F, Demir O. Effectiveness of various irrigation protocols for the removal of calcium grooves. J Appl Oral Sci. 2017 Jun;25(3):290-8. https://doi.org/10.1590/1678-7757-2016-0414
https://doi.org/10.1590/1678-7757-2016-0...
observed that PUI removed more Ca(OH)2 than XP-endo Finisher in the apical region of the teeth and found no statistically significant difference between PUI and XP-endo Finisher in removing Ca(OH)2 in the coronal and middle thirds. The same was observed by Lu Shi et al., who found greater efficacy of PUI when compared to other activation techniques, although without a statistically significant difference, noting that the complete removal of Ca(OH)2 from the apical curvature of the S-shaped root canals remains a challenge for irrigation protocols.4242 Shi L, Wu S, Yang Y, Wan J. Efficacy of five irrigation techniques in removing calcium hydroxide from simulated S-shaped root canals. J Dent Sci. 2022 Jan;17(1):128-34. https://doi.org/10.1016/j.jds.2021.05.015
https://doi.org/10.1016/j.jds.2021.05.01...

In another study using only optical microscopy to analyze Ca(OH)2 residue, Wigler et al.4040 Wigler R, Dvir R, Weisman A, Matalon S, Kfir A. Efficacy of XP-endo finisher files in the removal of calcium hydroxide paste from artificial standardized grooves in the apical third of oval root canals. Int Endod J. 2017 Jul;50(7):700-5. https://doi.org/10.1111/iej.12668
https://doi.org/10.1111/iej.12668...
observed that XP-endo Finisher and PUI removed significantly more Ca(OH)2 than conventional needle irrigation, corroborating the present results.

The results of a similar study in which the effectiveness of Ultrasonic, EndoActivator®, EDDY®, XP-endo® Finisher, and XP-endo® Shaper instruments for removing Ca(OH)2 remnants was verified using optics and scanning electron microscopy. Two of the root canals demonstrated the inability of all instruments tested to completely remove Ca(OH)2 slurries from the canals, altough EDDY® and XP-endo® Finisher were associated with less Ca(OH)2 remaining when creating the bur/acid cavity analyzed by SEM.1616 Marques-da-Silva B, Alberton CS, Tomazinho FS, Gabardo MC, Duarte MA, Vivan RR, et al. Effectiveness of five instruments when removing calcium hydroxide paste from simulated internal root resorption cavities in extracted maxillary central incisors. Int Endod J. 2020 Mar;53(3):366-75. https://doi.org/10.1111/iej.13223
https://doi.org/10.1111/iej.13223...

Consistent with the findings of this study, Denna et al.2727 Denna J, Shafie LA, Alsofi L, Al-Habib M, AlShwaimi E. Efficacy of the rotary instrument xp-endo finisher in the removal of calcium hydroxide intracanal medicament in combination with different irrigation techniques: a microtomographic study. Materials (Basel). 2020 May;13(10):2222-33. https://doi.org/10.3390/ma13102222
https://doi.org/10.3390/ma13102222...
and Kfir et al.3131 Kfir A, Blau-Venezia N, Goldberger T, Abramovitz I, Wigler R. Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove. Aust Endod J. 2018 Apr;44(1):26-31. https://doi.org/10.1111/aej.12204
https://doi.org/10.1111/aej.12204...
showed that XP-endo Finisher is a superior method for removing Ca(OH)2 from the apical third,3131 Kfir A, Blau-Venezia N, Goldberger T, Abramovitz I, Wigler R. Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove. Aust Endod J. 2018 Apr;44(1):26-31. https://doi.org/10.1111/aej.12204
https://doi.org/10.1111/aej.12204...
although it is also unable to completely remove Ca(OH)2 from the channel. For Denna et al., this result can be justified because of the lack of sufficient contact time between the file and the channel wall during the 1-min window indicated by the manufacturer's instructions. More testing would be worthwhile, keeping XP running longer or using it for several cycles to see if it could perform more effectively in removing Ca(OH)2.2727 Denna J, Shafie LA, Alsofi L, Al-Habib M, AlShwaimi E. Efficacy of the rotary instrument xp-endo finisher in the removal of calcium hydroxide intracanal medicament in combination with different irrigation techniques: a microtomographic study. Materials (Basel). 2020 May;13(10):2222-33. https://doi.org/10.3390/ma13102222
https://doi.org/10.3390/ma13102222...
,3131 Kfir A, Blau-Venezia N, Goldberger T, Abramovitz I, Wigler R. Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove. Aust Endod J. 2018 Apr;44(1):26-31. https://doi.org/10.1111/aej.12204
https://doi.org/10.1111/aej.12204...

Silva et al. then observed that PUI and XP could remove a greater amount of Ca(OH)2 in the middle third than in the cervical third, differing from this and other studies comparing the removal of Ca(OH)2 by thirds.4343 Tavella E Silva NC, Gibin JT, Rivera IC, Rached Junior FJ, Leoni GB, Raucci-Neto W. Calcium hydroxide paste removal strategies and bond strengths of epoxy- and silicate-based sealers. Aust Endod J. 2021 Aug;47(2):236-44. https://doi.org/10.1111/aej.12460
https://doi.org/10.1111/aej.12460...

Solutions such as NaOCl and EDTA, alone and in combination, have been used to remove Ca(OH)2.4444 Arslan H, Capar ID, Saygili G, Uysal B, Gok T, Ertas H, et al. Efficacy of various irrigation protocols on the removal of triple antibiotic paste. Int Endod J. 2014 Jun;47(6):594-9. https://doi.org/10.1111/iej.12194
https://doi.org/10.1111/iej.12194...
For a long time, NaOCl at different concentrations was the main irrigation solution used for disinfecting root canals. This solution has a broad spectrum of antimicrobial activity against microorganisms and biofilms that are difficult to eradicate. Meanwhile, EDTA is the most approved chemical for removal of the smear layer. It is also the most widely accepted irrigation solution and a recognized procedure in endodontic therapy for disinfection. As indicated by several studies, switching between these solutions during channel preparation procedures reduces the accumulation of debris and results in cleaner channels.4545 Berutti E, Marini R, Angeretti A. Penetration ability of different irrigants into dentinal tubules. J Endod. 1997 Dec;23(12):725-7. https://doi.org/10.1016/S0099-2399(97)80342-1
https://doi.org/10.1016/S0099-2399(97)80...

With a methodology similar to that described by Hamdan et al.2929 Hamdan R, Michetti J, Pinchon D, Diemer F, Georgelin-Gurgel M. The XP-Endo Finisher for the removal of calcium hydroxide paste from root canals and from the apical third. J Clin Exp Dent. 2017 Jul;9(7):e855-60. https://doi.org/10.4317/jced.53962
https://doi.org/10.4317/jced.53962...
and Kfir et al.,3131 Kfir A, Blau-Venezia N, Goldberger T, Abramovitz I, Wigler R. Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove. Aust Endod J. 2018 Apr;44(1):26-31. https://doi.org/10.1111/aej.12204
https://doi.org/10.1111/aej.12204...
the final irrigation solutions in this study were heated to 37° C to simulate body temperature, in an attempt to improve the effectiveness of XP-endo Finisher. According to the manufacturer, exposing the instrument to temperatures above 35 °C causes its molecular conformation for the austenitic phase, expands the instrument, and ultimately improves the cleaning of channels.

Several studies claim that Ca(OH)2 removal by ultrasonic agitation is superior to techniques with irrigators only.2121 van der Sluis LW, Wu MK, Wesselink PR. The evaluation of removal of calcium hydroxide paste from an artificial standardized groove in the apical root canal using different irrigation methodologies. Int Endod J. 2007 Jan;40(1):52-7. https://doi.org/10.1111/j.1365-2591.2006.01182.x
https://doi.org/10.1111/j.1365-2591.2006...
However, Balvedi et al.1818 Balvedi RP, Versiani MA, Manna FF, Biffi JC. A comparison of two techniques for the removal of calcium hydroxide from root canals. Int Endod J. 2010 Sep;43(9):763-8. https://doi.org/10.1111/j.1365-2591.2010.01718.x PMID:20546045
https://doi.org/10.1111/j.1365-2591.2010...
reported that there was no significant difference between syringe irrigation and PUI in the apical third of the root canals.

A recent study also evaluated the influence of irrigation protocols used to remove Ca(OH)2 on the adhesion of tricalcium silicate-based materials used as an apical barrier. Their results did not show a statistically significant difference between the irrigation techniques used in terms of resistance to biodentin displacement. However, less resistance to displacement was detected after using XP-endo Finisher compared to the other techniques in the groups, corroborating the results of the present study. The authors associate this fact with the superiority of XP-endo Finisher in removing Ca(OH)2 from irregularly shaped root canals, whose presence can interfere with the adhesion of these cements.4646 Ulusoy Öİ, Olcay K, Ulusoy M. Effect of various calcium hydroxide removal protocols on the dislodgement resistance of biodentine in an experimental apexification model. J Dent Sci. 2021 Jul;16(3):964-70. https://doi.org/10.1016/j.jds.2020.10.010
https://doi.org/10.1016/j.jds.2020.10.01...

Although not statistically significant, the apical third (3 mm from the root apex) often showed smallest values of cement penetration (linear measurements and penetration perimeter ratio) than the middle third (6 mm from the root apex) and cervical third (9 mm from the root apex). This may be due to the transport and accumulation of residual Ca(OH)2 to the apical region, with smaller area receiving a smaller volume of irrigating solution, and the complex anatomy of the periapical region.2727 Denna J, Shafie LA, Alsofi L, Al-Habib M, AlShwaimi E. Efficacy of the rotary instrument xp-endo finisher in the removal of calcium hydroxide intracanal medicament in combination with different irrigation techniques: a microtomographic study. Materials (Basel). 2020 May;13(10):2222-33. https://doi.org/10.3390/ma13102222
https://doi.org/10.3390/ma13102222...

Other factors that may have influenced cement penetration were sclerotic dentin and a low density of dentinal tubules in the apical region.2828 Ordinola-Zapata R, Bramante CM, Graeff MS, Carpio Perochena A, Vivan RR, Camargo EJ, et al. Depth and percentage of penetration of endodontic sealers into dentinal tubules after root canal obturation using a lateral compaction technique: a confocal laser scanning microscopy study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Sep;108(3):450-7. https://doi.org/10.1016/j.tripleo.2009.04.024
https://doi.org/10.1016/j.tripleo.2009.0...
The proportion of penetration of endodontic cement into the dentinal tubules was different in each experimental group. In all groups, irrigation with 17% EDTA was used to promote Ca(OH)2 chelation and facilitate its removal by NaOCl.4747 Margelos J, Eliades G, Verdelis C, Palaghias G. Interaction of calcium hydroxide with zinc oxide-eugenol type sealers: a potential clinical problem. J Endod. 1997 Jan;23(1):43-8. https://doi.org/10.1016/S0099-2399(97)80206-3
https://doi.org/10.1016/S0099-2399(97)80...

In this study, EDTA agitation with the XP-endo finisher for 60 s promoted the endodontic cement penetration, as well as expanded its penetration perimeter in comparison with the groups in which the agitation lasted only 30 s, probably due to the greater chelation of Ca(OH)2.4747 Margelos J, Eliades G, Verdelis C, Palaghias G. Interaction of calcium hydroxide with zinc oxide-eugenol type sealers: a potential clinical problem. J Endod. 1997 Jan;23(1):43-8. https://doi.org/10.1016/S0099-2399(97)80206-3
https://doi.org/10.1016/S0099-2399(97)80...

The present study has limitations resulting from an in vitro investigation, as well as those related to the methodology used. One of these limitations is the anatomy of root canals; although they have similar volumes, they could have been flatter and therefore influenced the results. Moreover, because a sample size calculation was not performed, the lack of statistical significance between peer comparisons should be carefully considered, as it may be due to low statistical power. Despite this, the results of this study can provide information that can help clinicians select the best protocol for use in clinical practice. However, more experiments are needed to identify an irrigation protocol that can effectively remove Ca(OH)2 residues and allow cement penetration into root canal spaces (Figure 3).

Figure 3
Demonstrative confocal laser scanning microscope images of each group (apical third), showing the cement penetration into root canal spaces.

Conclusion

Using XP-endo Finisher in irrigation was more effective than when using a needle and syringe in extending the penetration and penetration perimeter of endodontic cement. Stirring with XP-endo Finisher with 17% EDTA solution also contributed to an increase in the extent of penetration of endodontic cement into dentinal tubules, as well as the perimeter of penetration. Finally, the exclusive use of XP-endo Finisher and EDTA was more efficient in extending the penetration and perimeter of endodontic cement than when the instrument was used interchangeably with NaCOL and EDTA.

Acknowledgments

This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001.

References

  • 1
    Haapasalo M, Endal U, Zandi H, Coil JM. Eradication of endodontic infection by instrumentation and irrigation solutions. Endod Topics. 2005 Aug;10(1):77-102. https://doi.org/10.1111/j.1601-1546.2005.00135.x
    » https://doi.org/10.1111/j.1601-1546.2005.00135.x
  • 2
    Nair PN. On the causes of persistent apical periodontitis: a review. Int Endod J. 2006 Apr;39(4):249-81. https://doi.org/10.1111/j.1365-2591.2006.01099.x
    » https://doi.org/10.1111/j.1365-2591.2006.01099.x
  • 3
    Ghoddusi J, Javidi M, Zarrabi MH, Bagheri H. Flare-ups incidence and severity after using calcium hydroxide as intracanal dressing. N Y State Dent J. 2006 Jun-Jul;72(4):24-8.
  • 4
    Memon NA, Memon MR, Ali FU, Ane N. Assessment of the interappointment pain by using two different intracanal medicaments. Pak Oral Dent J. 2013 Apr;33(1):145-50. https://doi.org/10.5395/rde.2020.45.e26
    » https://doi.org/10.5395/rde.2020.45.e26
  • 5
    Uzunoglu E, Eymirli A, Uyanik MÖ, Çalt S, Nagas E. Calcium hydroxide dressing residues after different removal techniques affect the accuracy of Root-ZX apex locator. Restor Dent Endod. 2015 Feb;40(1):44-9. https://doi.org/10.5395/rde.2015.40.1.44
    » https://doi.org/10.5395/rde.2015.40.1.44
  • 6
    Orstavik D. Root canal disinfection: a review of concepts and recent developments. Aust Endod J. 2003 Aug;29(2):70-4. https://doi.org/10.1111/j.1747-4477.2003.tb00515.x
    » https://doi.org/10.1111/j.1747-4477.2003.tb00515.x
  • 7
    Law A, Messer H. An evidence-based analysis of the antibacterial effectiveness of intracanal medicaments. J Endod. 2004 Oct;30(10):689-94. https://doi.org/10.1097/01.DON.0000129959.20011.EE
    » https://doi.org/10.1097/01.DON.0000129959.20011.EE
  • 8
    Athanassiadis B, Walsh LJ. Aspects of solvent chemistry for calcium hydroxide medicaments. Materials (Basel). 2017 Oct;10(10):1219-27. https://doi.org/10.3390/ma10101219
    » https://doi.org/10.3390/ma10101219
  • 9
    Khaleel HY, Al-Ashaw AJ, Yang Y, Pang AH, Ma JZ. Quantitative comparison of calcium hydroxide removal by EndoActivator, ultrasonic and ProTaper file agitation techniques: an in vitro study. J Huazhong Univ Sci Technolog Med Sci. 2013 Feb;33(1):142-5. https://doi.org/10.1007/s11596-013-1087-x
    » https://doi.org/10.1007/s11596-013-1087-x
  • 10
    Donnermeyer D, Wyrsch H, Bürklein S, Schäfer E. Removal of calcium hydroxide from artificial grooves in straight root canals: sonic activation using EDDY versus passive ultrasonic irrigation and XPendo finisher. J Endod. 2019 Mar;45(3):322-6. https://doi.org/10.1016/j.joen.2018.11.001
    » https://doi.org/10.1016/j.joen.2018.11.001
  • 11
    Alkhudhairy FI, Yaman P, Dennison J, McDonald N, Herrero A, Bin-Shuwaish MS. The effects of different irrigation solutions on the bond strength of cemented fiber posts. Clin Cosmet Investig Dent. 2018 Oct;10:221-30. https://doi.org/10.2147/CCIDE.S155688
    » https://doi.org/10.2147/CCIDE.S155688
  • 12
    Neelakantan P, Sriraman P, Gutmann JL. Removal of calcium hydroxide intracanal medicament by different irrigants and irrigating techniques: a cone beam computed tomography analysis. Gen Dent. 2017 Nov-Dec;65(6):45-9.
  • 13
    Rödig T, Hirschleb M, Zapf A, Hülsmann M. Comparison of ultrasonic irrigation and RinsEndo for the removal of calcium hydroxide and Ledermix paste from root canals. Int Endod J. 2011 Dec;44(12):1155-61. https://doi.org/10.1111/j.1365-2591.2011.01937.x
    » https://doi.org/10.1111/j.1365-2591.2011.01937.x
  • 14
    Goldberg F, Artaza LP, De S. Influence of calcium hydroxide dressing on the obturation of simulated lateral canals. J Endod. 2002 Feb;28(2):99-101. https://doi.org/10.1097/00004770-200202000-00012
    » https://doi.org/10.1097/00004770-200202000-00012
  • 15
    Kim SK, Kim YO. Influence of calcium hydroxide intracanal medication on apical seal. Int Endod J. 2002 Jul;35(7):623-8. https://doi.org/10.1046/j.1365-2591.2002.00539.x
    » https://doi.org/10.1046/j.1365-2591.2002.00539.x
  • 16
    Marques-da-Silva B, Alberton CS, Tomazinho FS, Gabardo MC, Duarte MA, Vivan RR, et al. Effectiveness of five instruments when removing calcium hydroxide paste from simulated internal root resorption cavities in extracted maxillary central incisors. Int Endod J. 2020 Mar;53(3):366-75. https://doi.org/10.1111/iej.13223
    » https://doi.org/10.1111/iej.13223
  • 17
    Taşdemir T, Celik D, Er K, Yildirim T, Ceyhanli KT, Yeşilyurt C. Efficacy of several techniques for the removal of calcium hydroxide medicament from root canals. Int Endod J. 2011 Jun;44(6):505-9. https://doi.org/10.1111/j.1365-2591.2011.01854.x
    » https://doi.org/10.1111/j.1365-2591.2011.01854.x
  • 18
    Balvedi RP, Versiani MA, Manna FF, Biffi JC. A comparison of two techniques for the removal of calcium hydroxide from root canals. Int Endod J. 2010 Sep;43(9):763-8. https://doi.org/10.1111/j.1365-2591.2010.01718.x PMID:20546045
    » https://doi.org/10.1111/j.1365-2591.2010.01718.x
  • 19
    Lambrianidis T, Kosti E, Boutsioukis C, Mazinis M. Int Endod J. Removal efficacy of various calcium hydroxide/chlorhexidine medicaments from the root canal. 2006 Jan;39(1):55-61. https://doi.org/10.1111/j.1365-2591.2005.01049.x
    » https://doi.org/10.1111/j.1365-2591.2005.01049.x
  • 20
    Wiseman A, Cox TC, Paranjpe A, Flake NM, Cohenca N, Johnson JD. Efficacy of sonic and ultrasonic activation for removal of calcium hydroxide from mesial canals of mandibular molars: a microtomographic study. J Endod. 2011 Feb;37(2):235-8. https://doi.org/10.1016/j.joen.2010.11.019
    » https://doi.org/10.1016/j.joen.2010.11.019
  • 21
    van der Sluis LW, Wu MK, Wesselink PR. The evaluation of removal of calcium hydroxide paste from an artificial standardized groove in the apical root canal using different irrigation methodologies. Int Endod J. 2007 Jan;40(1):52-7. https://doi.org/10.1111/j.1365-2591.2006.01182.x
    » https://doi.org/10.1111/j.1365-2591.2006.01182.x
  • 22
    Kenee DM, Allemang JD, Johnson JD, Hellstein J, Nichol BK. A quantitative assessment of efficacy of various calcium hydroxide removal techniques. J Endod. 2006 Jun;32(6):563-5. https://doi.org/10.1016/j.joen.2005.10.065
    » https://doi.org/10.1016/j.joen.2005.10.065
  • 23
    Soares JA, Leonardo MR, Silva LA, Tanomaru Filho M, Ito IY. Effect of rotary instrumentation and of the association of calcium hydroxide and chlorhexidine on the antisepsis of the root canal system in dogs. Braz Oral Res. 2006 Apr-Jun;20(2):120-6. https://doi.org/10.1590/S1806-83242006000200006
    » https://doi.org/10.1590/S1806-83242006000200006
  • 24
    Salgado RJ, Moura-Netto C, Yamazaki AK, Cardoso LN, de Moura AA, Prokopowitsch I. Comparison of different irrigants on calcium hydroxide medication removal: microscopic cleanliness evaluation. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Apr;107(4):580-4. https://doi.org/10.1016/j.tripleo.2008.12.008
    » https://doi.org/10.1016/j.tripleo.2008.12.008
  • 25
    Lambrianidis T, Margelos J, Beltes P. Removal efficiency of calcium hydroxide dressing from the root canal. J Endod. 1999 Feb;25(2):85-8. https://doi.org/10.1016/S0099-2399(99)80002-8
    » https://doi.org/10.1016/S0099-2399(99)80002-8
  • 26
    Alturaiki S, Lamphon H, Edrees H, Ahlquist M. Efficacy of 3 different irrigation systems on removal of calcium hydroxide from the root canal: a scanning electron microscopic study. J Endod. 2015 Jan;41(1):97-101. https://doi.org/10.1016/j.joen.2014.07.033
    » https://doi.org/10.1016/j.joen.2014.07.033
  • 27
    Denna J, Shafie LA, Alsofi L, Al-Habib M, AlShwaimi E. Efficacy of the rotary instrument xp-endo finisher in the removal of calcium hydroxide intracanal medicament in combination with different irrigation techniques: a microtomographic study. Materials (Basel). 2020 May;13(10):2222-33. https://doi.org/10.3390/ma13102222
    » https://doi.org/10.3390/ma13102222
  • 28
    Ordinola-Zapata R, Bramante CM, Graeff MS, Carpio Perochena A, Vivan RR, Camargo EJ, et al. Depth and percentage of penetration of endodontic sealers into dentinal tubules after root canal obturation using a lateral compaction technique: a confocal laser scanning microscopy study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Sep;108(3):450-7. https://doi.org/10.1016/j.tripleo.2009.04.024
    » https://doi.org/10.1016/j.tripleo.2009.04.024
  • 29
    Hamdan R, Michetti J, Pinchon D, Diemer F, Georgelin-Gurgel M. The XP-Endo Finisher for the removal of calcium hydroxide paste from root canals and from the apical third. J Clin Exp Dent. 2017 Jul;9(7):e855-60. https://doi.org/10.4317/jced.53962
    » https://doi.org/10.4317/jced.53962
  • 30
    Keskin C, Sariyilmaz E, Sariyilmaz Ö. Efficacy of XP-endo finisher file in removing calcium hydroxide from simulated internal resorption cavity. J Endod. 2017 Jan;43(1):126-30. https://doi.org/10.1016/j.joen.2016.09.009
    » https://doi.org/10.1016/j.joen.2016.09.009
  • 31
    Kfir A, Blau-Venezia N, Goldberger T, Abramovitz I, Wigler R. Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove. Aust Endod J. 2018 Apr;44(1):26-31. https://doi.org/10.1111/aej.12204
    » https://doi.org/10.1111/aej.12204
  • 32
    Silva RV, Silveira FF, Horta MC, Duarte MA, Cavenago BC, Morais IG, et al. Filling effectiveness and dentinal penetration of endodontic sealers: a stereo and confocal laser scanning microscopy study. Braz Dent J. 2015 Oct;26(5):541-6. https://doi.org/10.1590/0103-6440201300138
    » https://doi.org/10.1590/0103-6440201300138
  • 33
    Bitter K, Paris S, Martus P, Schartner R, Kielbassa AM. A Confocal Laser Scanning Microscope investigation of different dental adhesives bonded to root canal dentine. Int Endod J. 2004 Dec;37(12):840-8. https://doi.org/10.1111/j.1365-2591.2004.00888.x
    » https://doi.org/10.1111/j.1365-2591.2004.00888.x
  • 34
    Gharib SR, Tordik PA, Imamura GM, Baginski TA, Goodell GG. A confocal laser scanning microscope investigation of the epiphany obturation system. J Endod. 2007 Aug;33(8):957-61. https://doi.org/10.1016/j.joen.2007.03.011
    » https://doi.org/10.1016/j.joen.2007.03.011
  • 35
    Berkhoff JA, Chen PB, Teixeira FB, Diogenes A. Evaluation of triple antibiotic paste removal by different irrigation procedures. J Endod. 2014 Aug;40(8):1172-7. https://doi.org/10.1016/j.joen.2013.12.027
    » https://doi.org/10.1016/j.joen.2013.12.027
  • 36
    Chawla A, Kumar V. Evaluating the efficacy of different techniques and irrigation solutions for removal of calcium hydroxide from the root canal system: A scanning electron microscope study. J Conserv Dent. 2018 Jul-Aug;21(4):394-400. https://doi.org/10.4103/JCD.JCD_246_17
    » https://doi.org/10.4103/JCD.JCD_246_17
  • 37
    Kok D, Rosa RA, Barreto MS, Busanello FH, Santini MF, Pereira JR, et al. Penetrability of AH plus and MTA fillapex after endodontic treatment and retreatment: a confocal laser scanning microscopy study. Microsc Res Tech. 2014. June;77(6):467-71. https://doi.org/10.1002/jemt.22371
    » https://doi.org/10.1002/jemt.22371
  • 38
    Piai GG, Duarte MA, Nascimento AL, Rosa RA, Só MV, Vivan RR. Penetrability of a new endodontic sealer: A confocal laser scanning microscopy evaluation. Microsc Res Tech. 2018 Nov;81(11):1246-9. https://doi.org/10.1002/jemt.23129
    » https://doi.org/10.1002/jemt.23129
  • 39
    Van Meerbeek B, Vargas M, Inoue S, Yoshida Y, Perdigão J, Lambrechts P, et al.; Microscopy investigations. Microscopy investigations. Techniques, results, limitations. Am J Dent. 2000 Nov;13(Spec No):3D-18D.
  • 40
    Wigler R, Dvir R, Weisman A, Matalon S, Kfir A. Efficacy of XP-endo finisher files in the removal of calcium hydroxide paste from artificial standardized grooves in the apical third of oval root canals. Int Endod J. 2017 Jul;50(7):700-5. https://doi.org/10.1111/iej.12668
    » https://doi.org/10.1111/iej.12668
  • 41
    Gokturk H, Ozkocak I, Buyukgebiz F, Demir O. Effectiveness of various irrigation protocols for the removal of calcium grooves. J Appl Oral Sci. 2017 Jun;25(3):290-8. https://doi.org/10.1590/1678-7757-2016-0414
    » https://doi.org/10.1590/1678-7757-2016-0414
  • 42
    Shi L, Wu S, Yang Y, Wan J. Efficacy of five irrigation techniques in removing calcium hydroxide from simulated S-shaped root canals. J Dent Sci. 2022 Jan;17(1):128-34. https://doi.org/10.1016/j.jds.2021.05.015
    » https://doi.org/10.1016/j.jds.2021.05.015
  • 43
    Tavella E Silva NC, Gibin JT, Rivera IC, Rached Junior FJ, Leoni GB, Raucci-Neto W. Calcium hydroxide paste removal strategies and bond strengths of epoxy- and silicate-based sealers. Aust Endod J. 2021 Aug;47(2):236-44. https://doi.org/10.1111/aej.12460
    » https://doi.org/10.1111/aej.12460
  • 44
    Arslan H, Capar ID, Saygili G, Uysal B, Gok T, Ertas H, et al. Efficacy of various irrigation protocols on the removal of triple antibiotic paste. Int Endod J. 2014 Jun;47(6):594-9. https://doi.org/10.1111/iej.12194
    » https://doi.org/10.1111/iej.12194
  • 45
    Berutti E, Marini R, Angeretti A. Penetration ability of different irrigants into dentinal tubules. J Endod. 1997 Dec;23(12):725-7. https://doi.org/10.1016/S0099-2399(97)80342-1
    » https://doi.org/10.1016/S0099-2399(97)80342-1
  • 46
    Ulusoy Öİ, Olcay K, Ulusoy M. Effect of various calcium hydroxide removal protocols on the dislodgement resistance of biodentine in an experimental apexification model. J Dent Sci. 2021 Jul;16(3):964-70. https://doi.org/10.1016/j.jds.2020.10.010
    » https://doi.org/10.1016/j.jds.2020.10.010
  • 47
    Margelos J, Eliades G, Verdelis C, Palaghias G. Interaction of calcium hydroxide with zinc oxide-eugenol type sealers: a potential clinical problem. J Endod. 1997 Jan;23(1):43-8. https://doi.org/10.1016/S0099-2399(97)80206-3
    » https://doi.org/10.1016/S0099-2399(97)80206-3

Publication Dates

  • Publication in this collection
    02 May 2022
  • Date of issue
    2022

History

  • Received
    17 June 2021
  • Reviewed
    22 Feb 2022
  • Accepted
    02 Feb 2022
Sociedade Brasileira de Pesquisa Odontológica - SBPqO Av. Prof. Lineu Prestes, 2227, 05508-000 São Paulo SP - Brazil, Tel. (55 11) 3044-2393/(55 11) 9-7557-1244 - São Paulo - SP - Brazil
E-mail: office.bor@ingroup.srv.br