Removal efficiency of calcium hydroxide dressing from the root canal

Comparative evaluation of removal of oil-based calcium hydroxide intracanal medicaments with two calcium chelators: An in vitro cone-beam computed tomography volumetric analysis

Background

Intracanal medicament (ICM) eliminates remaining bacteria and their toxins that were not removed by chemomechanical preparation during endodontic treatment.

Aim

The aim of this study was to compare and evaluate the removal of ozonated oil-based, silicone oil-based, and distilled water-based ICM with two calcium chelators, i.e., 0.2% chitosan and 17% ethylenediaminetetraacetic acid (EDTA).

Materials and Methods

A total of 54 mandibular permanent premolars were included and randomly allocated into 3 groups after cleaning and shaping along with thorough irrigation. Group 1 - ozonized calcium hydroxide group; Group 2 - Metapex group; Group 3 - Ca(OH)2 with distilled water group. Using an irrigant for removal, the teeth in each group were distributed at random to two subgroups - (A) 0.2% chitosan solution; (B) 17% EDTA solution. All the samples were ultrasonically agitated and the volume remaining in each tooth after retrieval was estimated using additional cone-beam computed tomography scans. The result was analyzed using one-way analysis of variance, following post hoc Tukey test.

Results

The mean percentage of ozonized Ca(OH)2, aqueous calcium hydroxide, and Metapex removed by 0.2% chitosan had greater values in comparison to 17% EDTA. When eliminating aqueous-based calcium hydroxide, both chelators showed similar effectiveness (P > 0.05). In contrast, 0.2% chitosan outperformed 17% EDTA in retrieving oil-based Ca(OH)2 (P < 0.05).

Conclusion

The aqueous-based form of Ca(OH)2 was removed more easily compared to the oil-based form. A combination of 0.2% chitosan and ultrasonics proved to be more effective than 17% EDTA in eliminating oil-based calcium hydroxide.

Comparative Evaluation of Novel Intracanal Medicaments on the Sealing Integrity of the Root Canal System: An In Vitro Study

AIM AND OBJECTIVE

This study aims to evaluate and compare the sealing integrity of endodontically treated teeth after the placement of novel nanoparticle-based intracanal medicaments through dye penetration.

MATERIALS AND METHODS

Total samples (n=56) with different experimental intracanal medicaments group 1: nano calcium oxide (nCaO) + propylene glycol (PPG) 400, group 2: nano zinc oxide (nZnO) + PPG400, group 3: nano magnesium oxide (nMgO) + PPG400, group 4: metapaste (control) were randomly divided for qualitative (n=28) and quantitative (n=28) analysis to determine the sealing integrity. The statistical analysis was performed using ANOVA, student t-test, and IBM SPSS Statistics for Windows, Version 20 (Released 2011; IBM Corp., Armonk, New York, USA), followed by determining sealing integrity using qualitative assay and quantitative assay.

RESULTS

Highly significant differences (p<0.0001) were observed between all four groups during intragroup comparison for qualitative assay. The nCaO-based intracanal medicament showed the maximum linear measurements of 2% methylene blue dye penetrated compared to metapaste. However, intragroup comparison for quantitative assay had non-significant differences (p<0.0001).

CONCLUSION

All intracanal medicaments allowed some leakage to occur. Minimum dye penetration was observed with the metapaste group (control) followed by nano zinc oxide (nZnO) + PPG400, nano magnesium oxide (nMgO) + PPG400, and maximum dye was absorbed with nano calcium oxide (nCaO) + PPG400.

Efficacy of various techniques in calcium silicate-based intracanal medicament removal: a micro-CT analysis

The purpose of this study was to evaluate the efficacy of different techniques in removing calcium silicate intracanal medicament (Bio-C Temp). Forty human single-canaled premolars were randomly distributed into five groups (n = 8). All root canals were instrumented, then filled with Bio-C Temp. Following 1-week incubation, the intra-canal medicament was removed using one of five techniques according to tooth group: conventional syringe irrigation, Endo Activator, passive ultrasonic irrigation (PUI), ProTaper Universal F3 and XP-endo Finisher (XPF). Micro-CT scanning was performed before and after removal of Bio-C Temp. All techniques significantly reduced the volume of Bio-C Temp (p < 0.001) without reaching complete elimination. The percentage of Bio-C Temp removed was significantly higher in the XPF group (98.2%) compared to conventional syringe irrigation (70.6%), the Endo Activator (75.7%), and the ProTaper Universal (76.6%). There was no significant difference between the XPF and PUI (95.1%) groups. None of the removal techniques were able to completely remove Bio-C Temp from the root canal. However, XPF was the most effective method, but was not statistically significant when compared to PUI. Clinical Relevance: This study demonstrated that both XPF and PUI outperform conventional irrigation in removing Bio-C Temp intracanal medicament.

Epoxy vs. Calcium Silicate-Based Root Canal Sealers for Different Clinical Scenarios: A Narrative Review

This study aimed to review the considerations for choosing a suitable sealer according to various endodontic scenarios. An electronic search of PubMed, Scopus, and the Web of Science was undertaken for the keywords of 'sealer choosing', 'appropriate sealer', 'suitable sealer', 'sealer for clinical scenario', and 'sealer for clinical situations'. However, the literature review revealed a lack of studies with practical clinical recommendations regarding the choice of appropriate endodontic root canal sealers for particular clinical situations of root canal treatment. Therefore, a narrative review was undertaken under the basis of the characteristics of an epoxy resin-based sealer (ERS) versus a calcium silicate-based sealer (CSS). Based on the evidence found through the review, the choice of an appropriate sealer in a variety of clinical scenarios was proposed. An ERS is recommended for one-visit non-vital cases, teeth with periodontal involvement, cracked teeth, and internal root resorption without root perforation. A CSS is recommended for vital or non-vital cases in multiple visits, teeth with internal root resorption with perforation or internal approach for external cervical resorption, teeth with open apices, and teeth with iatrogenic aberrations.

Efficacy of 2% Paradichlorobenzene, 10% Citric Acid, 17% Ethylenediaminetetraacetic Acid, and 0.2% Chitosan at Removing Calcium Hydroxide From the Root Canals

INTRODUCTION

Chronic infections often require the use of an intracanal medicament. Calcium hydroxide is the most commonly used intracanal medicament. However, retrieval of calcium hydroxide (CH) medicaments is a challenge.

AIM

This study evaluated the efficacy of 2% paradichlorobenzene, 10% citric acid, 17% ethylenediaminetetraacetic acid (EDTA), and 0.2% chitosan in removing calcium hydroxide from the root canals.

METHODS AND MATERIALS

Forty single-rooted mandibular premolars extracted for orthodontic reasons were selected for the study. After access opening, cleaning and shaping were performed following a standardized irrigation protocol, and the samples were pre-weighed for baseline weight. CH was placed in canals until the apex, and the specimen was incubated at 37 °C and 100% relative humidity for seven days. These samples were weighed again for quantitative analysis and subjected to cone beam computed tomography (CBCT) for volumetric analysis using ITK SNAP software (Penn Image Computing and Science Laboratory (PICSL), University of Pennsylvania, Philadelphia, PA). The samples were randomly divided into four groups based on the irrigant used for the removal of medicament. Group 1: 2% paradichlorobenzene; group 2: 10% citric acid; group 3: 17% EDTA; and group 4: 0.2% chitosan, all in combination with sonic agitation. After the removal of CH, weight and volumetric analyses were repeated, and the percentage difference was calculated.

STATISTICAL ANALYSIS

Statistical analysis was done using the one-way ANOVA test for both weight and volumetric assessment, and the inter-group comparison was made using the post hoc Tukey test.

RESULTS

The maximum retrieval was observed with 2% paradichlorobenzene by both weight (96.75%) and volumetric (91.42%) assessment, with p=0.00 and p=0.01, respectively. This was followed by 0.2% chitosan, 10% citric acid, and the least, 17% EDTA.

CONCLUSION

Two percent paradichlorobenzene combined with sonic agitation was most efficient in removing CH, followed by 0.2% chitosan, 10% citric acid, and 17% EDTA chitosan.

The efficacy of three passive ultrasonic irrigation systems on intracanal medicament removal in a novel standardised three-dimensionally printed model

This study compared the efficacy of several passive ultrasonic irrigation (PUI) systems in removing intracanal medicament using 3-dimensionally printed root canal model assembled with dentin specimen. After the placement of the model in the agar container (37°C), the intracanal medicament was removed using three different PUI instruments including CK file, Irrisafe and Endosonic Blue. Then, the area coated by the medicament and the volumetric percentage of the remaining medicament was measured. Irrisafe and Endosonic Blue showed higher removal efficacy than CK and the control regarding both the coated area and remaining volume (p < 0.05). CK showed the lowest efficacy among the tested PUI systems (p > 0.05). Notably, Endosonic Blue group showed the smallest coated area among the tested groups (p < 0.05). Conclusively, PUI systems made of nickel-titanium alloy with small dimensions, such as Endosonic Blue, have advantages for the removal of intracanal medicaments from curved root canals.

Farklı irrigasyon tekniklerinin kalsiyum hidroksit uzaklaştırma etkinliğinin Bilgisayarlı Sıvı Filtrasyon methodu kullanılarak mikrosızıntılarının değerlendirilmesi

Aim: To compare the efficiency of sonic irrigation, passive ultrasonic irrigation, and conventional syringe irrigation (CI) in removing pure and injectable calcium hydroxide (CH) from the root canals of mandibular second premolars by measuring the probable microleakage of residual CH particles in root canal obturation using computerized liquid filtration (CLF). Materials and Methods: Eighty instrumented mandibular second premolars were categorized into three experimental groups (n = 20 each) based on the irrigation method used for removing CH and a control group (n = 20) in which CH was not used. Each experimental group was divided into two equal groups (pure and injectable CH). After 1 week, CH was removed from the root canals, and the teeth were obturated. CLF measurements were performed 1 week after obturation. Nonparametric variables between two groups were compared using the Mann-Whitney U test, and the Kruskal-Wallis test was used to compare more than two groups. The significance level was set at p &lt; 0.05. Results: All experimental groups showed higher leakage values than the control group. The highest leakage values were evident in the CI group, and the lowest leakage values were found in the sonic (EDDY) irrigation group. No significant differences were detected among the different forms of CH. Conclusions: None of the analyzed techniques could completely remove CH from root canals, resulting in higher leakage values. Sonic irrigation with EDDY was the best in removing CH from root canals.

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

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.

Retrievability of Odontopaste and Metapex With 17% Ethylenediaminetetraacetic Acid and 10% Maleic Acid From Root Canals: An Invitro Study

Aim

To evaluate the efficacy of 10% maleic acid in comparison with 17% ethylenediaminetetraacetic acid (EDTA) in the removal of intracanal medicaments from the root canal system.

Materials and methods

Forty-eight extracted single-rooted mandibular premolars were decoronated to standardize the length of 14 mm. Chemomechanical preparation was done using the crown-down technique with Protaper files (Dentsply‑Maillefer, Ballaigues, Switzerland) till F4, followed by irrigation with 2 ml of 5.25% sodium hypochlorite (NaOCl) after each instrument, and 5 ml of 17% EDTA was used as the final irrigating agent.

Metapex (Meta Dental Corp. Ltd., Elmhurst, NY, USA) and Odontopaste (Australian Dental Manufacturing, Kenmore Hills, Qld, Australia) were the two intracanal medicaments that were used in this study.

Total samples were divided into two groups based on the intracanal medicament that was placed in the canal. In group 1, Metapex was injected into the root canal until the material extruded through the apex. In group 2, Odontopaste was placed into the canal until the material extruded through the root apex. Cleaning off the excess medicament was done with a moist cotton pellet. After temporary sealing with a cotton pellet and Cavit, all the samples were stored at 37 ºC and 100% relative humidity for a period of seven days. The teeth in each group were further randomly divided into three subgroups on the basis of the irrigant used for retrieval of medicament. In groups 1A and 2A, 1ml of 17% EDTA was used; in groups 1B and 2B, 1ml of 10% maleic acid was used; in groups 1C and 2C, 1ml of 0.9% saline was used. Sonic agitation for 1 minute, followed by a final rinse of 1 ml distilled water, was used in all the groups.

After the intracanal medicament was removed from the canal, the roots were longitudinally sectioned using a diamond disk (Bego, Berman, Germany). The residual medicament on each section was evaluated under a stereomicroscope (×30; Medilux, MDL-DS4-BI, Biosystems, Curitiba, PR, Brazil). The data were analyzed using SPSS version 23.0 software (IBM Corp., Armonk, NY). Kruskal-Wallis ANOVA and Mann-Whitney U test (post hoc) were applied for intergroup comparisons. A Wilcoxon signed-rank test was applied for intragroup comparisons.

Results

Both the chelators, 17% EDTA and 10% maleic acid, removed the Odontopaste significantly better than Metapex. However, 17% EDTA was more effective in the removal of Odontopaste. 10% Maleic acid showed better results in the removal of Metapex than 17% EDTA.

Conclusion

None of the chelating agents was able to totally retrieve the intracanal medicaments. When compared to Metapex, Odontopaste showed significantly better retrievability from the root canal with both 17% EDTA and 10% Maleic acid, whereas the retrievability of Metapex was significantly better with 10% Maleic acid in comparison to 17% EDTA.

The effects of root canal perforation repair materials on the bond strength of fiber posts

INTRODUCTION

This study aimed to evaluate the effect of calcium hydroxide and bioceramics used in perforation repair on the bonding strength of fiber posts via a push-out test.

METHODOLOGY

This study used 106 extracted single-rooted human mandibular premolar teeth. Root canal preparations were performed with a rotary file system and perforations were created in the middle third of each tooth. The samples were randomized into two main experimental groups, one with calcium hydroxide and one without. Each group had four subgroups in which different bioceramic cements were applied (n = 11) and a control group (n = 9). The root canals perforations were repaired using MTA, Biodentine, Bioaggregate, and Endosequence BC root repair material. A fiber post was applied to each tooth and a push-out test was performed. The samples were examined at 40× magnification with a digital microscope in order to identify fracture type.

RESULTS

Bonding strength was calculated in MPa. A statistical analysis showed that the calcium hydroxide had no effect on the bonding strength of the fiber posts. A comparison of the perforation repair materials revealed that Biodentine in the calcium hydroxide group and Bioaggregate in both groups decreased the bonding strength compared to the other materials (p < 0.05). The most common failure type was adhesive failure between the dentin and resin cement (38.16%).

CONCLUSIONS

The use of different perforation repair materials can affect the bonding strength of fiber posts. Therefore, the choice of perforation repair material should be made on an individual basis.

Efficacy of glycolic acid for the removal of calcium hydroxide from simulated internal Resorption cavities

OBJECTIVES

This study evaluated the efficacy of 5% and 10% glycolic acid solutions for the removal of calcium hydroxide medicament from artificial internal resorption cavities.

MATERIALS AND METHODS

A total of 170 human maxillary premolars were selected and artificial internal resorption cavities were prepared using round burs and 37% orthophosphoric acid in the apical third of the root halves. Entire canal and resorption cavity were filled with calcium hydroxide paste. Then, the specimens were assigned to 2 control groups or ten experimental groups according to the irrigating solutions used for medicament removal with and without activation with ultrasonic energy as following: 5% glycolic acid, 10% glycolic acid, 17% EDTA, and 10% citric acid and distilled water. The resorption cavities were examined under different magnifications using stereomicroscopy and scanning electron microscopy (SEM). The calcium hydroxide remnants in the resorption cavity were scored by 2 evaluators using a 4-scoring scale. The data were analyzed with Kruskal-Wallis H tests with 5% significance threshold.

RESULTS

There was no significant difference regarding the distribution of removal scores among non-activated solutions (P > 0.05). In activated groups, 10% glycolic acid irrigation removed significantly more amount of calcium hydroxide than EDTA and distilled water (P < 0.05). No significant difference was found between the efficacy of 10% glycolic and citric acid (P > 0.05). Citric acid, 5% glycolic acid, and EDTA showed similar removal scores (P > 0.05). Passive ultrasonic irrigation significantly improved calcium hydroxide removal scores in 10% glycolic acid, citric acid, and EDTA groups (P < 0.05). The SEM examination revealed that the specimens that were scored 0 are not entirely free of calcium hydroxide remnants.

CONCLUSION

Concentration of 10% glycolic acid removed significantly more calcium hydroxide paste from resorption cavities than EDTA when used with passive ultrasonic irrigation. Although passive ultrasonic irrigation favored medicament removal in all irrigating solutions, complete elimination of medicament remnants was unattainable.

CLINICAL RELEVANCE

This study showed the improved efficacy of ultrasonically activated 10% glycolic acid in removing the calcium hydroxide medicament from the internal resorption cavity.

Effect of tip insertion depth and irradiation parameters on the efficacy of cleaning calcium hydroxide from simulated lateral canals using Er:YAG laser- or ultrasonic-activated irrigation

Background/purpose

Laser-activated root canal irrigation (LAI) with an Er:YAG laser is considered more effective than other irrigation methods, whereas the effectiveness of LAI in cleaning lateral canals far from the laser tip remains unclear. This study aimed to compare the efficacy of removing calcium hydroxide [Ca(OH)₂] paste from lateral canals using LAI or ultrasonic-activated irrigation (UAI), and to examine the effect of tip insertion depth and laser irradiation parameters on cleaning efficacy.

Materials and methods

Radiopaque Ca(OH)₂ paste (Calcipex II) was injected into lateral canals 6 mm from the root apex in 192 J-shaped simulated root canal models. LAI (Erwin AdvErl; 30 or 70 mJ; 10 or 20 pulses per second; laser tip R200T or R600T) and UAI (ENAC SE10; output setting: 3) were performed 3 times for 20 s. The laser tip was placed at 8–0 mm coronal to the lateral canal location. The volume of Ca(OH)₂ paste before and after the experiment was measured using micro-CT (SMX-100CT).

Results

The Ca(OH)₂ removal rate by LAI was significantly higher than UAI at all tip insertion depths. Ca(OH)₂ removal rate in LAI was significantly lower at the 8 mm position compared with other positions (P < 0.05). When the tip insertion depth was fixed at this position, Ca(OH)₂ removal rate increased significantly when pulse energy and tip diameter were increased (P < 0.05).

Conclusion

LAI removed Ca(OH)₂ paste from lateral canals away from the tip more effectively than UAI. Increasing the pulse energy and tip diameter improved the removal efficiency.

Effect of Various Irrigating Devices on the Removal of Two Different Forms of Calcium Hydroxide from Internal Resorption Cavities

The present study aimed to investigate the efficiency of passive ultrasonic irrigation (PUI), EndoActivator (EA), standard needle irrigation (SNI), and XP-endo Finisher files in removing pure calcium hydroxide (pCH) and injectable CH from in vitro root resorption cavities. Using a rotary system, the root canals of 116 extracted single rooted teeth were prepared. Imitated internal resorption cavities were then created in root halves. The specimens were divided into two groups according to the form of CH (n = 58): (I) pCH; (II) injectable CH. The teeth of each group were randomly divided into six subgroups: negative control (n = 5), positive control (n = 5), PUI (n = 12), XP-endo Finisher (n = 12), EA (n = 12), and SNI (n = 12). The root canals were irrigated using NaOCl and EDTA and split longitudinally, and both halves were evaluated with a stereomicroscope. Kruskal–Wallis and Mann–Whitney U tests were used to analyze data. The present results revealed that PUI completely removed pCH in 79% and injectable CH in 70.8% of the internal resorption cavities which was significantly higher than other methods (p < 0.05). There was no statically significant difference between different forms of CH in terms of CH removal (p=0.918). The PUI technique was observed as the most efficient method of P-CH and injectable CH removal from a replicated internal resorption cavity. Finally, according to the findings, different forms of CH were comparable in terms of CH removal.

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

OBJECTIVES

This study aims to evaluate the efficacy of the rotary instrument XP-endo Finisher for the removal of Ca(OH)₂ aided by different irrigation regimens.

METHODS

Sixteen double-rooted upper premolar human teeth were selected for the study. Thirty-two canals were prepared using a ProTaper Next rotary system up to X3. Then, the canals were filled with Ca(OH)₂. The volume of Ca(OH)₂ inside the canals was measured by microcomputed tomography (micro-CT). After that, the teeth were randomly allocated into two experimental groups, i.e., A and B (n = 16 canals). In group A, Ca(OH)₂ was removed using the master apical file (X3). In group B, Ca(OH)₂ was removed using a XP-endo finisher. In half of both groups (n = 8), syringe irrigation (SI) was used, while passive ultrasonic irrigation (PUI) was used for the other half. After removal, the remaining volume of Ca(OH)₂ was measured. All data were statistically analyzed using two-way ANOVA with Tukey's post hoc test.

RESULTS

The percentages of remaining Ca(OH)₂ in the apical thirds of all canals were significantly higher as compared with the middle and coronal thirds in all groups (p < 0.05). There was no significant difference between different files and techniques (p > 0.05).

CLINICAL SIGNIFICANCE

This study presents a new method for the removal of Ca(OH)₂ from root canals.

Evaluation of the effect of calcium hydroxide and endodontic irrigants on the push-out bond strength of fiber post - an in vitro study

Background

In recent years, fibre-reinforced composite posts have been proposed for the restoration of root filled teeth as an alternative to pre-fabricated posts or metal dowels.

Aims and objectives

The aim of the study was to analyze the effect of endodontic irrigants used for removal of calcium hydroxide on the push-out bond strength of fiber posts to root canal dentin.

Methods

Forty human permanent single-rooted mandibular premolars with relatively straight roots were taken and access cavities were prepared and biomechanical preparation done using Rotar Y protaper file till size F2. The samples were divided into Experimental group and Control group. In Experimental groups Intracanal dressing of calcium hydroxide was removed by 2.5% NaOCl and 17% EDTA (Group1), MTAD (Group II) and Qmix (Group III). Control group did not receive Intracanal calcium hydroxide dressing. Canals were obturated using size F2 protaper gutta-percha points and AH plus sealer. After storage for 24 hours, post space was prepared. Forty Tenax fiber post (Coltene) were cemented with Rely X U200 resin. The roots were then transversally sectioned into 3 slices of 1mm thickness corresponding to cervical, middle and apical third. The slices obtained were subjected to micro-push-out bond strength test using a universal testing machine. The data obtained was subjected to statistical analysis using One-Way ANOVA test. P value of .05 was considered as statistically significant level.

Results

The mean push-out bond strength values for controls, NaOCl/EDTA, MTAD and QMIX group at cervical third were 10.17, 15.84, 20.39 and 20.98 whereas at apical third 4.78, 8.85, 11.66 and 12.10.

Conclusion

Qmix showed higher push-out bond strength values followed by MTAD and NaOCl/EDTA. All the groups showed lowest push-out bond strength values in the apical third followed by middle and the maximum in the cervical region.

Effectiveness of various irrigation protocols for the removal of calcium hydroxide from artificial standardized grooves

Objective

The aim of this study was to investigate the ability of laser-activated irrigation (LAI), XP-endo Finisher, CanalBrush, Vibringe, passive ultrasonic irrigation (PUI), and conventional syringe irrigation systems on the removal of calcium hydroxide (CH) from simulated root canal irregularities.

Material and Methods

The root canals of one hundred and five extracted single-rooted teeth were instrumented using Reciproc rotary files up to size R40. The teeth were split longitudinally. Two of the three standard grooves were created in the coronal and apical section of one segment, and another in the middle part of the second segment. The standardized grooves were filled with CH and the root halves were reassembled. After 14 days, the specimens were randomly divided into 7 experimental groups (n=15/group). CH was removed as follows: Group 1: beveled needle irrigation; Group 2: double side-vented needle irrigation; Group 3: CanalBrush; Group 4: XP-endo Finisher; Group 5: Vibringe; Group 6: PUI; Group 7: LAI. The amount of remaining CH in the grooves was scored under a stereomicroscope at 20× magnification. Statistical evaluation was performed using Kruskal–Wallis and Bonferroni-Correction Mann–Whitney U tests.

Results

Groups 1 and 2 were the least efficient in eliminating CH from the grooves. Groups 6 and 7 eliminated more CH than the other protocols; however, no significant differences were found between these two groups (P>.05).

Conclusions

Nevertheless, none of the investigated protocols were able to completely remove all CH from all three root regions. LAI and PUI showed less residual CH than the other protocols from artificial grooves.

Comparison of different irrigation and agitation methods for the removal of two types of calcium hydroxide medicaments from the root canal wall: an in-vitro study

Background and aim

Comparison of different irrigation and agitation methods for the removal of two types of calcium hydroxide medicaments from the root canal walls.

Methods

Fifty extracted single rooted teeth were selected for this study. After decoronation, the root canals of these teeth were prepared to the size F3 (30 no.) using rotary ProTaper file system. These samples were randomly divided into four groups. Group 1 (n=20) were filled completely with water based calcium hydroxide (CH), Group 2 (n=20) were filled with oil based CH using lentulo spiral, Group 3 (n=5) - the positive control group received the CH as intracanal medication, but no subsequent removal, Group 4 (n=5) - the negative control did not receive CH placement. Further on, Group 1 and Group 2 were divided into four sub-groups (n=5). In sub-group A we performed conventional syringe irrigation with side-vented needle sub-group B) manual dynamic agitation, sub-group C sonic agitation using endoactivator, sub-group D passive ultrasonic irrigation (PUI). Roots were split longitudinally into mesial and distal halves. Digital images of the root canal walls were acquired by a Dental Operating Microscope (DOM) and assessed by using a scoring criteria at different thirds (coronal, middle and apical) of the root canal as follows: score 1, score 2, score 3, and score 4. Data were analyzed applying one-way analysis of variance (ANOVA) and Tukey’s multiple comparison tests at a 95% confidence interval (P < 0.05).

Results

Statistically significant differences were not found between the experimental groups and the negative group in any one third of the root canal (P>0.05). However, a difference did exist between the experimental groups and the positive control group (P<0.05). None of the experimental groups totally removed CH substances from root canal walls.

Conclusion

Among all experimental groups, removal of CH was best achieved by sonic agitation using endoactivator followed by passive ultrasonic irrigation (PUI), manual dynamic agitation and conventional syringe irrigation with side-vented needle.

Efficacy of self-adjusting file, XP-endo finisher and passive ultrasonic irrigation on the removal of calcium hydroxide paste from an artificial standardized groove

The purpose of this study was to compare the effectiveness of self-adjusting file (SAF), XP-endo finisher (XP), passive ultrasonic irrigation (PUI) and conventional syringe and needle irrigation (SNI) in the removal of Ca(OH)₂ from an artificial groove. Eighty mandibular incisors with single oval canals were prepared to size 40/0.04 and split longitudinally. A standardised groove was prepared in the apical third and filled with Ca(OH)₂ . The root halves were reassembled and divided into two control groups (n = 4) and four experimental groups (n = 18) according to the removal methods used. The amount of residual Ca(OH)₂ was evaluated using a four-grade scoring system. The differences among the groups were analysed using the Kruskal-Wallis test (P < 0.05). SAF, XP and PUI removed significantly more Ca(OH)₂ than SNI (P < 0.001), although there were no significant differences among them (P = 0.209). None of the tested methods could completely clean Ca(OH)₂ from the groove.

Comparison of different techniques for removal of calcium hydroxide from straight root canals: an in vitro study

To compare four different techniques for removal of calcium hydroxide from straight root canals. The present study used the design suggested by Lee et al. (Int Endod J 37:607-612, 32) and van der Sluis et al. (Int Endod J 40:52-57, 17). One-hundred and ten extracted human teeth with straight root canals were prepared to ISO-size 50 and split longitudinally. Two lateral grooves were prepared, filled with calcium hydroxide and the root halves reassembled in a muffle. Calcium hydroxide was removed using one of five techniques: (1) passive ultrasonic irrigation, (2) hydrodynamic irrigation using RinsEndo^®, (3) sonic irrigation using the EndoActivator^®, (4) motor-driven plastic brush (CanalBrush™), and (5) manual irrigation with a syringe as the control group. Distilled water was used as irrigant. Cleanliness of the grooves was scored under a microscope with 40× magnification. For intraindividual reproducibility and interrater agreement, Cohens Kappa was calculated. Results of scoring were analyzed using a non-parametric test. Post hoc pairwise comparisons were used for irrigation techniques (α = 0.05). Passive ultrasonic irrigation performed significantly better than all other groups in the apical groove. Significant differences were found between RinsEndo and CanalBrush (P = 0.01855) and CanalBrush and syringe irrigation (P = 0.00021). In the coronal groove, passive ultrasonic irrigation performed significantly superior and hand irrigation performed significantly worse than all other groups. A statistically significant interaction was shown between irrigation technique and localization of the groove (P = 0.01358). The coronal grooves showed more remaining calcium hydroxide than the apical grooves. Complete removal of calcium hydroxide from the root canal could not be achieved with any of the techniques investigated. The highest degree of cleanliness resulted from the use of passive ultrasonic irrigation.

Removal of calcium hydroxide from Weine Type II systems using photon-induced photoacoustic streaming, passive ultrasonic, and needle irrigation: a microcomputed tomography study

Objective

This study compared the effectiveness of Er:YAG laser-activated irrigation (PIPS), passive ultrasonic irrigation (PUI) with EndoUltra and standard needle irrigation (SNI) in the removal of calcium hydroxide [Ca(OH)2] from the mesial roots of Weine Type II mandibular molars.

Material and Methods

Thirty mandibular molars were screened by µCT for the presence of mesial roots with complex intra-canal anatomy and a common apical foramen. The teeth were enlarged to a standardized 25/.06 preparation and filled with Ca(OH)2 paste. Specimens were divided into three groups (n=10) according to the technique used for Ca(OH)2 removal: PIPS, at 15 Hz and 20 mJ using a 9 mm long, 600 µm diameter tip; PUI using a 15/.02 tip; and SNI (30 Ga. side-vented needle). Equal volumes of 8.25% NaOCl and 17% EDTA were used in all groups. µCT was used to measure the initial amount of Ca(OH)2 present and to assess the residual volume of Ca(OH)2 following each irrigation protocol. Data were analyzed using Tukey HSD and Kruskal-Wallis tests (α=5%).

Results

The mean volume of Ca(OH)2 before removal was significantly higher in the coronal third than in the middle and apical third (p<0.001). Ca(OH)2 was similarly removed from the coronal and middle thirds with the three methods used (p>0.05). PIPS (median 0%; IQR: 0-0) showed significant higher Ca(OH)2 removal in the apical third than PUI (median 100%, IQR: 85-100) and SNI (median 47%; IQR: 16-72) (p<0.001).

Conclusions

PIPS laser-activation was more effective for the removal of Ca(OH)2 from mesial roots of mandibular molars with Weine Type II canal configurations than PUI with EndoUltra and SNI.

Retrievability of calcium hydroxide intracanal medicament with three calcium chelators, ethylenediaminetetraacetic acid, citric acid, and chitosan from root canals: An in vitro cone beam computed tomography volumetric analysis

Aim:

This study compared the amount of aqueous-based and oil-based calcium hydroxide remaining in the canal, after removal with two different chelators 17% EDTA, 20% Citric acid and 0.2% Chitosan in combination with ultrasonic agitation.

Methods and Material:

Cleaning and shaping of root canals of 28 mandibular premolar was done and canals were filled either with Metapex or Ca(OH)₂ mixed with distilled water. Volumetric analysis was performed utilizing cone beam-computed tomography (CBCT) after seven days of incubation. Ca(OH)₂ was removed using either 17% EDTA, 20% Citric acid or 0.2% Chitosan in combination with ultrasonic agitation.

Statistical analysis used:

Volumetric analysis was repeated and percentage difference was calculated and statistically analyzed using Kruskal-Wallis and Mann-Whitney U test.

Results:

All the three chelators failed to remove aqueous-based as well as oil-based Ca(OH)₂ completely from the root canal. Aqueous-based Ca(OH)₂ was easier to be removed than oil-based Ca(OH)₂. 0.2% Chitosan in combination with ultrasonics performed better than 17% EDTA and 20% citric acid in removal of Ca(OH)₂.

Conclusion:

Combination of 0.2% Chitosan and ultrasonic agitation results in lower amount of Ca(OH)₂ remnants than 17% EDTA, 20% Citric acid irrespective of type of vehicle present in the mix.

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

AIM

To compare the efficacy of the XP-endo finisher file (XP) (FKG Dentaire, La Chaux de Fonds, Switzerland) to that of passive ultrasonic irrigation (PUI) and conventional syringe and needle irrigation (SNI) in the removal of calcium hydroxide paste from an artificial standardized groove in the apical third of root canals.

METHODOLOGY

The root canals of 68 mandibular incisors with single oval canals were prepared using Mtwo instruments (VDW GmbH, Munich, Germany) up to size 40, .04 taper. Each tooth was split longitudinally, and in one half of the root, a standardized groove was prepared in the apical part of the specimen. The grooves were filled with Ca(OH)₂ , and the root halves were reassembled. The roots were randomly divided into two control groups (n = 4) and three experimental groups (n = 20) according to the Ca(OH)₂ methods used: XP, PUI and SNI. The amount of remaining medicament was evaluated under X25 magnification using a 4-grade scoring system. Kappa values were calculated for intra- and interobserver agreement evaluation. The differences in the Ca(OH)₂ scores amongst the different groups were analysed using the Kruskal-Wallis test.

RESULTS

None of the tested methods could completely clean the Ca(OH)₂ from the artificial standardized groove in the apical third of the root canals. XP and PUI removed significantly more Ca(OH)₂ than SNI (P < 0.001), with no significant differences between them (P = 0.238).

CONCLUSIONS

XP and PUI were more effective in removing Ca(OH)₂ from artificial standardized grooves in the apical third of root canals than SNI.

Effectiveness of four different techniques in removing intracanal medicament from the root canals: An in vitro study

Aim:

To evaluate the effectiveness of different techniques in removing calcium hydroxide (Ca(OH)₂) from the root canal.

Materials and Methods:

Twenty-four freshly extracted mandibular premolars were instrumented using ProTaper rotary instruments. The teeth were longitudinally split into two halves, cleaned of debris. The two halves were then reassembled and filled with Ca(OH)₂ and were divided into four groups. In Group I, the teeth were irrigated with 5 mL of 2.5% sodium hypochlorite (NaOCl) and 5 mL of 17% of ethylenediaminetetraacetic acid. In Group II, the teeth were irrigated with 5 mL of 2.5% NaOCl and a rotary ProTaper F3 instrument was used. In Group III, the teeth were irrigated with 5 mL of 2.5% NaOCl and agitated using an ultrasonic unit. In Group IV, the teeth were irrigated with 5 mL of 2.5% NaOCl and a CanalBrush was used to remove Ca(OH)₂. The roots were disassembled, and photographs were taken. The amount of residual Ca(OH)₂ was calculated using an image analysis software as a percentage of the total canal surface area. The data were analyzed using one-way analysis of variance and post-hoc Tukey test.

Results:

CanalBrush and ultrasonic techniques showed significantly less residual Ca(OH)₂ than irrigants and rotary techniques. There was no significant difference between the rotary and irrigant techniques.

Conclusion:

None of the techniques used were completely able to remove Ca(OH)₂ from the root canals. But the CanalBrush and ultrasonic techniques were significantly better than the rotary instrument and irrigant groups.

A titration model for evaluating calcium hydroxide removal techniques

Objective

Calcium hydroxide (Ca(OH)₂) has been used in endodontics as an intracanal medicament due to its antimicrobial effects and its ability to inactivate bacterial endotoxin. The inability to totally remove this intracanal medicament from the root canal system, however, may interfere with the setting of eugenol-based sealers or inhibit bonding of resin to dentin, thus presenting clinical challenges with endodontic treatment. This study used a chemical titration method to measure residual Ca(OH)₂ left after different endodontic irrigation methods.

Material and Methods

Eighty-six human canine roots were prepared for obturation. Thirty teeth were filled with known but different amounts of Ca(OH)₂ for 7 days, which were dissolved out and titrated to quantitate the residual Ca(OH)₂ recovered from each root to produce a standard curve. Forty-eight of the remaining teeth were filled with equal amounts of Ca(OH)₂ followed by gross Ca(OH)₂ removal using hand files and randomized treatment of either: 1) Syringe irrigation; 2) Syringe irrigation with use of an apical file; 3) Syringe irrigation with added 30 s of passive ultrasonic irrigation (PUI), or 4) Syringe irrigation with apical file and PUI (n=12/group). Residual Ca(OH)₂ was dissolved with glycerin and titrated to measure residual Ca(OH)₂ left in the root.

Results

No method completely removed all residual Ca(OH)₂. The addition of 30 s PUI with or without apical file use removed Ca(OH)₂ significantly better than irrigation alone.

Conclusions

This technique allowed quantification of residual Ca(OH)₂. The use of PUI (with or without apical file) resulted in significantly lower Ca(OH)₂ residue compared to irrigation alone.

Intra-canal calcium hydroxide removal by two rotary systems: A comparative study

Aim:

The presence of calcium hydroxide (Ca(OH)₂) in the root canal interferes with the apical root canal sealing and may result in periapical lesions in the long run. The present study was aimed to compare the efficacy of two rotary systems of Race and Mtwo in the removal of Ca (OH)₂ aqueous-based from distobuccal canals of human maxillary molars.

Materials and Methods:

A total of 44 distobuccal root canals of human maxillary molars were randomly distributed into two groups of 20 canals each and two control groups. Specimens in each group were instrumented with similar master apical rotary (MAR) and flexible files according to the manufacture's guidelines. The Ca (OH)₂ paste was placed in canals using # 20 lentulo and radiographs were taken from the two dimensions. The roots were incubated for 1 week at 37°C and 100% humidity and Ca (OH)₂ was removed from canals by MAR, afterward. Then, the roots were longitudinally split in halves by diamond disk and chisel without entering the root canals. Photos were taken from the canals’ walls by a stereomicroscope with × 10 magnification. Next, according to a defined scoring system, photos were scored by four endodontists, so that scores 1 and 2 (nonvisible remnants or scattered remnants of Ca(OH)₂) were considered as acceptable and scores 3 and 4 (distinct mass or densely-packed mass of Ca(OH)₂) were regarded as nonacceptable.

Results:

The obtained findings indicated that in coronal, middle, and apical portions of the root canal, 45, 60, and 65% of Mtwo specimens and 40, 50, and 55% of specimens prepared by the Race system acquired an acceptable score (1 and 2), respectively. Moreover, the results showed no significant difference between the two groups (P > 0.05).

Conclusions:

Both Mtwo and Race rotary systems with acceptable removal efficiency (score 1 and 2) were similarly able to remove Ca(OH)₂

Calcium Hydroxide Dressing Influences the Obturation of Simulated Lateral Canals

AIM

The aim of this study was to investigate the influence of calcium hydroxide dressing on the filling of simulated lateral canals by different obturation techniques.

MATERIALS AND METHODS

Sixty single-root-premolars were instrumented. Simulated lateral canals were drilled on each third of the roots. The teeth were divided into four groups: no dressing and obturation by lateral condensation technique (G1), dressing with calcium hydroxide and obturation by lateral condensation technique (G2), no dressing and obturation by hybrid technique (G3) and, dressing with calcium hydroxide and obturation by hybrid technique (G4). The teeth were maintained at 37°C in 100% humidity for 7 days, and obturation techniques were performed. Radiographs were taken and filled or unfilled lateral canals were counted. Data were analyzed using analysis of variance (ANOVA) followed by Tukey's test (a = 5%).

RESULTS

The hybrid technique filled large number of lateral canals as compared to lateral condensation technique, regardless the use of intracanal medication (p < 0.05). Calcium hydroxide decreased the number of lateral canals filled for both lateral and hybrid techniques (p < 0.05). Significant differences were observed when comparing the number of filled and unfilled lateral canals in the same root third of each group (p < 0.05).

CONCLUSION

Regardless the obturation technique, calcium hydroxide dressing reduced the penetration of filling material in simulated lateral canals.

CLINICAL SIGNIFICANCE

The persistence of calcium hydroxide residues reduces the penetration of filling material in simulated lateral canals, possibly representing a potential cause of failure in the future.

Effectiveness of different irrigation protocols on calcium hydroxide removal from simulated immature teeth after apexification

Aim: To evaluate the effectiveness of different irrigation solutions and ultrasonic activation of the irrigation solutions on the removal of calcium hydroxide (Ca(OH)₂) from the simulated immature root canals after apexification.

Materials and methods: One-hundred and one single-rooted teeth were used. The root canals were shaped with ProTaper rotary files up to F5. Simulation of roots with immature apices was carried out using size 4 Unicore drills. An injectable Ca(OH)₂ was injected into each root canal, and packed to the working length. Then, cotton pellets were placed over canal orifices, and apical and coronal parts of the roots were sealed with resin-modified glass ionomer cement, and light cured. Specimens were stored in distilled water for 3 months at 37°C. After 3 months, the temporary coronal seal was removed and the samples were randomly divided into: (a) saline (n = 20), (b) ultrasonic activation of saline (n = 20), (c) sodium hypochlorite (NaOCl) (n = 20), (d) ultrasonic activation of NaOCl (n = 15), (e) chlorhexidine digluconate (CHX) (n = 20) and one positive control group (n = 3) and one negative control group (n = 3). The amount of remaining Ca(OH)₂ on the canal walls was measured under stereomicroscope with 30× magnification. Comparisons between groups were made by the non-parametric Kruskal-Wallis test and Dunn post-test at a significance level of p < 0.05.

Results: There were no significant differences among the saline, ultrasonic activation of saline, NaOCl, ultrasonic activation of NaOCl and CHX (p > 0.05) groups.

Conclusions: Irrigation solutions and ultrasonic activation of the irrigation solutions could not completely remove Ca(OH)₂ from the simulated immature root canals.

Calcium hydroxide dressing residues after different removal techniques affect the accuracy of Root-ZX apex locator

OBJECTIVES

This study compared the ability of several techniques to remove calcium hydroxide (CH) from the root canal and determined the influence of CH residues on the accuracy of the electronic apex locator.

MATERIALS AND METHODS

Root canals of 90 human maxillary lateral incisors with confirmed true working length (TWL) were prepared and filled with CH. The teeth were randomly assigned to one of the experimental groups according to the CH removal technique (n = 14): 0.9% saline; 0.9% saline + master apical file (MAF); 17% ethylenediamine tetraacetic acid (EDTA); 17% EDTA + MAF; 5.25% sodium hypochlorite (NaOCl); 5.25% NaOCl + MAF. Six teeth were used as negative control. After CH removal, the electronic working length was measured using Root-ZX (Morita Corp.) and compared with TWL to evaluate Root-ZX accuracy. All specimens were sectioned longitudinally, and the area of remaining CH (CH) and total canal area were measured using imaging software.

RESULTS

The EDTA + MAF and NaOCl + MAF groups showed better CH removal than other groups (p < 0.05). Root-ZX reliability to prevent overestimated working length to be > 85% within a tolerance of ± 1.0 mm (p < 0.05). There was strong negative correlation between amount of CH residues and EAL accuracy (r = -0.800 for ± 0.5 mm; r = -0.940 for ± 1.0 mm).

CONCLUSIONS

The mechanical instrumentation improves the CH removal of irrigation solutions although none of the techniques removed the dressing completely. Residues of CH medication in root canals affected the accuracy of Root-ZX adversely.

Retrievabilty of calcium hydroxide intracanal medicament with Chitosan from root canals: An in vitro CBCT volumetric analysis

AIM

This study compared the amount of aqueous-based and oil-based calcium hydroxide [Ca(OH)2 ] remaining in the canal, after removal with two different chelators 17% EDTA and 0.2% Chitosan in combination with ultrasonic agitation.

MATERIALS AND METHODS

Cleaning and shaping of root canals of 28 mandibular premolar was done and canals were filled either with Metapex or Ca(OH)2 mixed with distilled water. Volumetric analysis was performed utilizing cone beam-computed tomography (CBCT) after 7 days of incubation. Ca(OH)2 was removed using either 17% EDTA or 0.2% Chitosan in combination with ultrasonic agitation. Volumetric analysis was repeated and percentage difference was calculated and statistically analysed using Kruskal-Wallis and Mann-Whitney U test.

RESULTS

Both the chelators failed to remove aqueous-based as well as oil-based Ca(OH)2 completely from the root canal. Aqueous-based Ca(OH)2 was easier to be removed than oil-based Ca(OH)2. 0.2% Chitosan was significantly more effective for removal of oil-based Ca(OH)2 (P < 0.01) while both 17% EDTA and 0.2% Chitosan were equally effective in removing aqueous-based Ca(OH)2 .

CONCLUSION

Combination of 0.2% Chitosan and ultrasonic agitation results in lower amount of Ca(OH)2 remnants than 17% EDTA irrespective of type of vehicle present in the mix.

Efficacy of ethylene-diamine-tetra-acetic acid associated with chlorhexidine on intracanal medication removal: a scanning electron microscopy study

The aim of this study was to evaluate the effectiveness of 17% ethylene-diamine-tetra-acetic acid (EDTA) used alone or associated with 2% chlorhexidine gel (CHX) on intracanal medications (ICM) removal. Sixty single-rooted human teeth with fully formed apex were selected. The cervical and middle thirds of each canal were prepared with Gates Glidden drills and rotary files. The apical third was shaped with hand files. The specimens were randomly divided into two groups depending on the ICM used after instrumentation: calcium hydroxide Ca(OH)(2) +CHX or Ca(OH)(2) +sterile saline (SS). After seven days, each group was divided into subgroups according to the protocol used for ICM removal: instrumentation and irrigation either with EDTA, CHX+EDTA, or SS (control groups). All specimens were sectioned and processed for observation of the apical thirds by using scanning electron microscopy. Two calibrated evaluators attributed scores to each specimen. The differences between the protocols for ICM removal were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Friedman and Wilcoxon signed rank tests were used for comparison between the score of debris obtained in each root canal third. Remains of Ca(OH)(2) were found in all specimens independently of the protocol and ICM used (P > 0.05). Seventeen percent EDTA showed the best results in removing ICM when used alone (P < 0.05), particularly in those associated with CHX. It was concluded that the chelating agent 17% EDTA significantly improved the removal of ICM when used alone. Furthermore, the type of the vehicle associated with Ca(OH)(2) also plays a role in the ICM removal.

Effect of rotary instrument associated with different irrigation techniques on removing calcium hydroxide dressing

Calcium hydroxide [Ca(OH)2 ] residues in root canals may compromise sealing of filling and endodontic treatment success. The aim of this study was to compare the efficacy of using rotary instrument associated with EndoActivator, EndoVac, passive ultrasonic irrigation (PUI), and conventional needle irrigation (CNI), in Ca(OH)2 removal from root canal, by means of scanning electron microscopy (SEM) images. Sixty-six human canines were prepared with the Protaper system up to F5 and filled with Ca(OH)2 . After 7 days, Ca(OH)2 was removed with rotary instrument F5 associated with the irrigation techniques used in each group (n = 15): GI (CNI), GII (EndoVac), GIII (EndoActivator) and GIV (PUI). In all groups 15 mL of 2.5% NaOCl and 3 mL of 17% EDTA were used for Ca(OH)2 removal. The Ca(OH)2 residues was evaluated by SEM in the middle and apical third using a system of scores. The results were analyzed by the Kruskal-Wallis and Dunn tests (α = 0.05). None of the techniques completely removed the Ca(OH)2 from root canals. There was no difference between EndoActivator, EndoVac and PUI (P > 0.05), but the three techniques removed more Ca(OH)2 than the CNI (P < 0,05), in the middle and apical thirds of the root canal. It was concluded that the rotary instrument combined with EndoActivator, EndoVac, and PUI was shown to be more efficient than the rotary instrument combined with the CNI in removing Ca(OH)2 from the root canal.

Eficácia da irrigação ultrassônica passiva na remoção de hidróxido de cálcio

INTRODUÇÃO: Remanescentes de Hidróxido de Cálcio [Ca(OH)2] podem interferir na qualidade da obturação endodôntica. OBJETIVO : Avaliar a eficácia da Irrigação Ultrassônica Passiva (IUP) associada à técnica convencional na remoção de medicação intracanal à base de Ca(OH)2. METODOLOGIA: Trinta dentes humanos anteriores monorradiculares foram usados. Os canais radiculares foram preparados com instrumentos manuais tipo K e preenchidos com medicação intracanal à base de Ca(OH)2, contendo PMCC e propilenoglicol. Após sete dias, a pasta de Ca(OH)2 foi removida de todos os canais radiculares com um instrumento manual e irrigação de NaOCl 1% com seringa. Os espécimes foram randomizados em dois grupos (n=12) de acordo com a irrigação final: Irrigação Manual - agitação manual de EDTA 17 % e irrigação de NaOCl 1%; IUP - agitação ultrassônica de NaOCl 1% (três ativações de 20s) seguida da ativação de EDTA 17% por 1 min. O Grupo Controle (n=6) não recebeu medicação intracanal. Todos os espécimes foram clivados e a quantidade de Ca(OH)2 remanescente foi calculada com o auxílio do estereomicroscrópio (20×). Os testes Kruskall-Wallis e Wilcoxon foram utilizados para avaliar a porcentagem de Ca(OH)2 remanescente. RESULTADO: O grupo da IUP apresentou, estatisticamente, as menores porcentagens de Ca(OH)2 remanescente, quando comparado ao grupo da Irrigação Manual, independentemente dos terços analisados (P < 0,05). O terço apical apresentou a maior quantidade de medicação residual, em ambos os grupos (P < 0,05). CONCLUSÃO : A associação da IUP com a técnica convencional demonstrou ser mais eficiente na remoção de medicação intracanal à base de Ca(OH)2 do que a combinação da Irrigação Manual com a técnica convencional.

Nonsurgical management of large periapical lesion in mature and immature teeth using different calcium hydroxide formulations: case series

This case series evaluates the effectiveness of different calcium hydroxide formulations with various vehicles in management of large periapical lesion in mature and immature teeth. This will help clinicians to make informed judgments about which formulations of calcium hydroxide should be used for specific endodontic procedures.

Removal efficiency of calcium hydroxide dressing from the root canal without chemically active adjuvant

AIM

Compare the efficiency in removing two calcium hydroxide [Ca(OH)2] preparations from root canal and apical third using single use syringe, ultrasonics and RinsEndo((®)) with saline solution.

MATERIALS AND METHODS

One hundred and eighty human singlerooted teeth were instrumented using ProTaper((®)) rotary system, divided into two groups according to Ca(OH)2 filling. A: Powder mixed with water, B: Pulpdent((®)). Each group was divided into three subgroups for the irrigation: A1, B1: Single use syringe; A2, B2: Ultrasonics; A3, B3: RinsEndo((®)). Teeth were split longitudinally, photographed and imported into Adobe Photoshop. The percentage ratios of Ca(OH)2 remaining in the canal and in the apical third were calculated. Data were statistically analyzed using 'ANOVA two-way' and 'univariate tests'.

RESULTS

(a) Remnants of medicament were found in all teeth, (b) no statistically significant difference in the elimination of both Ca(OH)2 from the entire canal (p = 0.436), however, mixed powder was better eliminated from the apical third (p = 0.005), (c) no statistically significant difference among the irrigation techniques in the whole canal (p = 0.608), though, RinsEndo((®)) and ultrasonics were the most effective in cleaning the apical third (p = 0.032) when mixed powder was used.

CONCLUSION

None of the techniques removed completely Ca(OH)2 from the canal. In the apical third, RinsEndo((®)) and ultrasonics were the most effective when mixed powder was used.

CLINICAL SIGNIFICANCE

Ca(OH)2, the most commonly used intracanal dressing, should be completely eliminated before the obturation to assure a good endodontic sealing. Based on the results of this study, RinsEndo((®)) and ultrasonics were the most effective in removal of Ca(OH)2 especially the powder mixed with water presentation.