|Year : 2018 | Volume
| Issue : 3 | Page : 287-292
The efficiency of different irrigation solutions and techniques for the removal of triple antibiotic paste from simulated immature root canals
Y Ustun1, S Düzgün2, T Aslan1, A Aktı3
1 Department of Endodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey
2 Fatma Kemal Timuçin ADSM Hospital, Adana, Turkey
3 Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Selçuk University, Konya, Turkey
|Date of Acceptance||02-May-2017|
|Date of Web Publication||09-Mar-2018|
Dr. Y Ustun
Department of Endodontics, Faculty of Dentistry, Erciyes University, Melikgazi, 38039 Kayseri
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Introduction: The purpose of this study was to evaluate the efficiencies of different irrigation protocols in the removal of triple antibiotic paste (TAP) from root canals. Materials and Methods: A total of 127 extracted human maxillary incisor teeth were prepared. Then, root-end resection of 3 mm was accomplished to simulate immature apex model. The root canals were filled with TAP, after 21 days, randomly divided into nine groups according to irrigation systems and solutions (n = 13). Conventional irrigation (CI) groups - Group 1: Root canal irrigation was performed with CI by Peracetic acid (PAA) solution, Group 2: Root canal irrigation was performed with CI by etidronic acid 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP) + sodium hypochlorite (NaOCl) solution, Group 3: Root canal irrigation was performed with CI by ethylenediaminetetraacetic acid (EDTA)/NaOCl solutions. Vibringe system groups - Group 4: Root canal irrigation was performed with Vibringe system by PAA solution, Group 5: Root canal irrigation was performed with Vibringe system by HEBP + NaOCl solution, Group 6: Root canal irrigation was performed with Vibringe system by EDTA/NaOCl solution. EndoVac system groups - Group 7: Root canal irrigation was performed with EndoVac system by PAA solution, Group 8: Root canal irrigation was performed with EndoVac system by HEBP + NaOCl solution, Group 9: Root canal irrigation was performed with EndoVac system by EDTA/NaOCl solution. Control Group: (n = 0). Samples were sectioned vertically, and the amount of remaining medicament was scored for each root half and data were statistically analyzed. Results: Among the irrigation systems, CI groups showed the highest scores at both apical and coronal parts (P < 0.05). In comparisons among the solutions, at the apical part, PAA groups showed the highest scores (P < 0.05). At the coronal part, EDTA + NaOCl groups showed the lowest score values (P < 0.05). Conclusion: The use of irrigation systems improved the removal of TAP from the simulated immature root canals. Also, as an irrigation solution EDTA gives more promising results than PAA and HEBP solutions.
Keywords: EndoVac, immature teeth, irrigation, triple antibiotic paste, Vibringe
|How to cite this article:|
Ustun Y, Düzgün S, Aslan T, Aktı A. The efficiency of different irrigation solutions and techniques for the removal of triple antibiotic paste from simulated immature root canals. Niger J Clin Pract 2018;21:287-92
|How to cite this URL:|
Ustun Y, Düzgün S, Aslan T, Aktı A. The efficiency of different irrigation solutions and techniques for the removal of triple antibiotic paste from simulated immature root canals. Niger J Clin Pract [serial online] 2018 [cited 2020 Aug 8];21:287-92. Available from: http://www.njcponline.com/text.asp?2018/21/3/287/226962
| Introduction|| |
Dental trauma is a frequently occurring situation in children which can lead to pulpal necrosis. The prevalence of dental trauma injuries are reported as 4%–59% and most of these injuries occurred in incisor teeth. If pulp necrosis occurs in an immature permanent tooth, it may lead to uncompleted root formation with thin and short root canal walls that increase the risk of subsequent fracture. An optimal approach for treating the immature permanent tooth with a necrotic pulp should be the induction of apical papilla stem cells to regenerate a pulp-like tissue.
Regenerative endodontics has been defined as “biologically based procedures designed to replace damaged structures, including dentin and root structures, as well as cells of the pulp-dentin complex.” The success of this “stem cell–based therapy” depends on the survival and differentiation capacities of stem cells. With this point of view, in a regenerative procedure, the optimum disinfection of the root canal system is the most crucial step for survival, proliferation, and differentiation of stem cells.
Many disinfection protocols include the use of intracanal medicaments. Several successful case reports used a triple antibiotic (ciprofloxacin, metronidazole, and minocycline) paste triple antibiotic paste (TAP) for disinfection of root canal systems before the inducing blood for initiation of regeneration. TAP is an effective antimicrobial agent, that creates suitable conditions for tissue revascularization.
Ruparel et al. found that TAP had detrimental effects on human apical papilla stem cells. Therefore, TAP should be completely removed from root canals to inhibit its detrimental effects. In addition, residual TAP in the root canal space could have negative effects on sealer penetration and tooth discoloration.
Sodium hypochlorite (NaOCl) solutions are widely used for the removal of TAP with traditional syringe irrigation techniques.,,, However, complete cleaning of the root canal system could not be achieved with NaOCl. Different devices for irrigation delivery have been recommended to increase the penetration of irrigation solutions within the root canal system.
The Vibringe System (Vibringe B. V. Corp, Amsterdam, the Netherlands) is an irrigation device that combines manual delivery and sonic activation of the solution. The Vibringe is a cordless handpiece that fits in a special disposable 10-mL Luer-Lock syringe that is compatible with every irrigation needle. Another system, EndoVac (Discus Dental, Culver City, CA, USA) is an apical negative pressure irrigation device designed to deliver irrigating solutions to the apical portion of the canal system and to suction out debris. The negative pressure of the EndoVac system effectively cleans dentinal walls. Apical negative pressure irrigation at a sufficient volume and flow removes the smear layers and displaces debris. 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP), also known as etidronate or etidronic acid has been recommended as a potential alternative to ethylenediaminetetraacetic acid (EDTA) or citric acid because this agent does not show short-term reactivity with NaOCl. Peracetic acid (PAA) is one of the strongest disinfectants known. PAA has antibacterial, antiviral, sporicidal, and antifungal effects. Currently, PAA solutions are frequently used in water treatment, the food industry, veterinary medicine, and the decontamination and sterilization of thermosensitive medical and hospital equipment and devices. PAA has been used for the elimination of biofilm formation in different areas. The acetic acid content is suggested to be responsible for the inorganic material dissolution. In smear layer removal, 2.25% PAA solution has comparable effects as 17% EDTA. Nevertheless, PAA is recommended for use in lower concentrations such as 0.5% because 2.25% PAA is reported to be relatively caustic when it is in contact with oral mucosa.,,,
The purpose of this study was to evaluate the efficiencies of different irrigation protocols in the removal of TAP from root canals. The null hypothesis was that irrigation protocols did not differ in the removal of TAP.
| Materials and Methods|| |
Ethical approval was obtained from the Review Committee of the research foundation of Erciyes University of Medical Sciences in Kayseri, Turkey (2015/333), before investigation.
A total of 127 single-rooted, noncarious human maxillary incisor teeth with completed apices were selected. Soft tissues and calculus were removed mechanically from the root surfaces with a periodontal scaler. Buccolingual and mesiodistal radiographs were taken from the specimens to evaluate root canal anatomy. Teeth with severely curved canals, cracks, and resorptive defects were excluded from the study. Only teeth with single and straight root canals were chosen. The teeth were then stored in 4°C distilled water until used. The root canals were shaped with ProTaper rotary files (Dentsply Maillefer, Ballaigues, Switzerland) up to an F5 (size 50) master apical file size. During preparation, the root canal was irrigated with 2 mL of 5% NaOCl solution after each instrument. Then, root-end resection of 3 mm was accomplished by use of no. 702 tapered fissure bur in low-speed straight handpiece to simulate immature apex model.
Equal portions of metronidazole (IE Ulagay, Istanbul, Turkey), ciprofloxacin (Biofarma, Istanbul, Turkey) and minocycline (Zentiva, Frankfurt, Germany) were mixed with distilled water (a powder/liquid ratio of 3:1). The root canals were filled with TAP using a lentulo spiral, and intracanal filling material was gently condensed with a hand plugger to be sure if completely filled. Then, specimens were remounted in the Eppendorf vials. Access to the root canals was temporarily sealed with a cotton pellet and the temporary filling material (Cavit, Espe, Seefeld, Germany), and specimens were then kept at 37°C with 95% relative humidity for 3 weeks. To simulate in vivo clinical conditions of an immature permanent tooth, in terms of a relative resistance against the irrigation pressure samples were embedded into arrangement foam.
The specimens were divided randomly into nine groups (n = 13) and irrigated as follows:
The root canals were irrigated conventionally with a 27-gauge side-vented irrigation needle (KerrHawe Irrigation Probe; KerrHawe SA, Bioggio, Switzerland) that was inserted apically 1 mm short of predetermined working length, and the root canals were flushed with 10 mL 0.5% PAA solution for 1 min.
Five milliliter 5% NaOCl solution and 5 ml 18% HEBP solution were mixed and 10 ml 9% HEBP/2.5% NaOCl solution was obtained. Then, conventional irrigation (CI) was performed with 10 ml 9% HEBP/2.5% NaOCl solution for 1 min as described in Group 1.
CI was performed with 5 ml %17 EDTA solution for 30 s as described in Group 1. Then, following 17% EDTA irrigation, 5 ml 5% NaOCl irrigation is performed for 30 s for each tooth.
Vibringe disposable syringe was filled with 10 ml 0.5% PAA solution. The 27-gauge side vented irrigation needle was placed 1 mm short of the predetermined working length. The root canal was flushed with activated Vibringe system for 1 min.
Five milliliter 5% NaOCl solution and 5 ml 18% HEBP solution were mixed and 10 ml 9% HEBP/2.5% NaOCl was obtained. Vibringe disposable syringe was filled with 10 ml 9% HEBP/2.5% NaOCl solution. The 27-gauge side-vented irrigation needle was placed 1 mm short of the predetermined working length. The root canal was flushed with activated Vibringe system for 1 min.
First, Vibringe disposable syringe was filled with 5 ml 17% EDTA solution. The irrigation needle was placed 1 mm short of the predetermined working length. The root canal was irrigated with activated Vibringe system for 30 s. Then, Vibringe disposable syringe is filled with 5 ml 5%NaOCl solution. The irrigation needle was placed 1 mm short of the predetermined working length. The root canal was flushed with activated Vibringe system for 30 s.
The canals were first irrigated for 1 min with 10 ml 0.5% PAA solution using the EndoVac system macrocannulas. When a clogging occurred during the suctioning procedure, the macrocanulla replaced with a new one.
A volume of 5 ml 5% NaOCl solution and 5 ml 18% HEBP solution were mixed, and 10 ml 9% HEBP/2.5% NaOCl solution was obtained. The canals were first irrigated for 1 min with 10 ml 9% HEBP/2.5% NaOCl solution using the EndoVac system macrocannulas. When a clogging occurred during the suctioning procedure, the macrocanulla replaced with a new one.
The canals were first irrigated for 30 s with 5 ml 17% EDTA solution and after then for 30 s with 5 ml 5%NaOCl irrigation, using the EndoVac system macrocannulas. When a clogging occurred during the suctioning procedure, the macrocanulla replaced with a new one.
Five roots were left empty as a negative control group, and five roots were filled with TAP, but no irrigation procedure was applied and accepted as a positive control group.
After the final irrigation, 2 ml distilled water was used to remove any remaining irrigation solution. The canals were dried with paper points, and longitudinal grooves were prepared on the buccal and lingual surfaces of each root with a diamond disk without penetrating the root canal. Thirteen roots in each group were sectioned into 2 halves; thus, 26 samples were obtained from each group (n = 26). The amount of remaining medicament at coronal and apical root thirds of each root half was evaluated The root canal surfaces were acquired for this purpose using a digital camera mounted on a stereomicroscope (Leica MZ16 A; Leica Microsystems, Wetzlar, Germany) at 30x magnification and transferred to the computer. Three calibrating dentists were blinded to the technique used to remove TAP, and the residual amount of TAP in the root canal was scored according to the scoring system described by Van Der Sluis et al.:
- Score 0, the canal was empty
- Score 1, TAP was present in less than half of the canal
- Score 2, TAP covered more than half of the canal
- Score 3, the canal was completely filled with TAP.
Data were subjected to statistical interpretation using Kruskal–Wallis and Tukey post hoc tests at a 95% confidence level (α = 0.05).
| Results|| |
Medians, standard errors of the means, and 25%–75% quartiles are shown in [Table 1]. The scores for the removal of TAP are shown in [Figure 1]. None of the groups showed complete removal of TAP from the root canals [Table 1].
In comparisons among the irrigation methods, CI groups showed the highest score values at both apical and coronal parts (P< 0.05); however, no statistically significant difference was found among EndoVac and Vibringe groups (P > 0.05).
In comparisons among the irrigants used, PAA groups showed the highest score values at the apical part (P< 0.05); besides, no statistically significant difference was found among EDTA + NaOCl groups and HEBP + NaOCl groups (P > 0.05). At the coronal part, EDTA + NaOCl groups showed the lowest score values (P< 0.05), and no statistically significant difference was found among PAA groups and HEBP + NaOCl groups (P > 0.05).
When the groups were compared for each part of the root canal, a significant difference was found (P< 0.05) in terms of TAP removal. Significant differences are shown in [Table 1].
| Discussion|| |
The aim of this study was to compare the efficacy of the different irrigation protocols in the removal of TAP from the simulated immature root canal system model. Several studies including removal of the intracanal medicaments have been limited to teeth with mature root morphologies.,, There is only one study in the literature that evaluated the removal of TAP from immature teeth model. For this reason, the results of experiments performed using with mature roots do not reflect the results of teeth with incomplete root development. Immature necrotic permanent teeth have a wide root canal and apical foramen. Thus, root-end resection of 3 mm was accomplished for obtaining immature permanent tooth. However, immature teeth have different dentine structure than mature teeth have. This could be one of the limitations of the present study. To simulate in vivo clinical conditions and create a selective resistance against irrigant flow, immature permanent tooth model was embedded into arrangement foam.
In regenerative endodontic applications, TAP has been left up to 3 weeks in root canals, and therefore, in the present study, TAP was left in the root canals for 3 weeks to simulate clinical conditions.
Several methods such as of digital photographs, stereomicroscopes, scanning electron microscopes, micro–computed tomography imaging, and spiral computed tomographic imaging have been used to evaluate the amount of residues on the canal walls.,,, In the present study, stereomicroscopy was used, and the remnants of TAP on the root canal walls were evaluated using a scoring method similar to that used in a previous study.
Arslan et al. evaluated the various irrigation protocols on the removal of TAP from the apical root third, and they reported that PUI with 1% NaOCl improved the removal of TAP when compared with conventional syringe Irrigation (CI). Berkhoff et al. evaluated on radiolabeled TAP removal by different irrigation procedures, and they concluded that positive pressure using a syringe, Endoactivator (Dentsply, Tulsa, OK, USA), EndoVac, and PUI groups showed quite similar mean percentage removal of radiolabeled TAP. Akman et al. investigated the removal efficiency of modified TAP from the mature root canals with different irrigation protocols (CI, Self-Adjusting File (SAF; ReDent-Nova, Ra'anana, Israel), PUI, EndoVac, and Endoactivator). They reported that CI was the least efficient technique for TAP removal.
The results of the present study were in accordance with the study of Akman et al. and CI was the least efficient method for removal of TAP in apical and coronal parts, and there was no significant difference between the EV and Vibringe groups at apical and coronal parts. Although there was no significant difference between the EV and Vibringe groups at apical and coronal parts, at the apical part, the scores of EV group was lower than Vibringe group.
To the best to our knowledge, there is no information in literature searching the efficiency of Vibringe in removal of TAP. Thus, data were not available for comparing other irrigation techniques. The previous studies mentioned that agitation methods improve the removal efficiency of intracanal medicaments., The results of the present study were in accordance with this information, Vibringe was superior to CI for removal of TAP. It continuously serves to deliver irrigant in a pulsating manner directly into the root canal through standard needle. It uses sonic flow technology combined with acoustic streaming.
Sagsen et al. evaluated the effect of PAA on removing calcium hydroxide from the root canals, and they concluded that 1% PAA was superior for the removal of Ca(OH)2 from the root canals. Previous studies used NaOCl or EDTA irrigation solutions for removal of TAP.,,, The present study was the first study used PAA and HEBP irrigation solutions for the removal of TAP intracanal medication. In comparisons among the irrigation solutions, there were significant differences. Sagsen et al. reported that 1% PAA was superior to EDTA and NaOCl. However, in the present study, PAA group had the worst scores at the apical part. This may be occurred because of the different chemical contents of Ca(OH)2 and TAP. At the coronal part, EDTA/NaOCl group was superior to other groups.
HEBP was stated as a weak chelator which does not harm the mineral content of dentine, and it does not diminish the activity of NaOCl in combined usage., In the present study at apical parts, HEBP showed better performance than PAA. This result could be related to different chemical ingredients of irrigants. Further researches are needed about this subject.
Berkhoff et al. reported that labeled TAP could not be removed with the use of EDTA and different irrigation activation methods. They used a quantitative method for the measurement of the remaining TAP and reported that more than 85% of the TAP was found in the dentin. They also showed that most of the TAP was found in depths >350 mm. In the present study, another chelating agents including PAA and HEBP besides EDTA were used. Contradictory to the results of Berkhoff et al., the use of irrigation activation techniques improved the removal of TAP from the root canals in the present study. However, TAP medicament was not radiolabelled in the present study. Thus, only macroresidues that were visible on 30x magnified stereomicroscope photos were evaluated. This could be another limitation of the study.
| Conclusion|| |
Within the limitations of this study, it can be concluded that the use of irrigation activation regimens significantly improved the removal of TAP from the root canals when compared with conventional syringe irrigation. However, none of the activation regimens completely removed TAP from the root canals. In addition, EDTA irrigation solution may be recommended for removal TAP. Further research requires evaluating the efficiency of HEBP and PAA irrigation solutions.
This manuscript is supported by Erciyes University Scientific Reseach Projects Department (Project number: TSA-2014-5587).
Financial support and sponsorship
This manuscript is supported by Erciyes University Scientific Reseach Projects Department (Project number: TSA-2014-5587).
Conflicts of interest
There are no conflicts of interest.
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