Five methods of calcium hydroxide intracanal placement: an in vitro evaluation

Micro-computed tomography analysis of calcium hydroxide delivery efficacy in C-shaped canal system of mandibular second molars

BACKGROUND

Calcium hydroxide [Ca(OH)2] is widely accepted as a biocompatible interappointment intracanal medicament. This study aimed to analyze the efficacy of Ca(OH)2 placement into the C-shaped canal system of mandibular second molars using the syringe method with and without lentulo spiral utilizing micro-computed tomography (micro-CT).

METHODS

Twenty-four extracted mandibular second molars were instrumented and classified into C-shaped floors (n = 12) and non-C-shaped floors (n = 12). Both groups were placed with Ca(OH)2 using the syringe system, then all teeth were scanned and cleaned, and placed with Ca(OH)2 again but with the syringe system followed by lentulo spiral and rescanned. The specimens were scanned using micro-CT to analyze the volume, volume percentage, uncontacted surface area, and uncontacted surface area percentage of Ca(OH)2 with the two delivery methods in the entire canal and at the apical 4 mm of the canal. Mann-Whitney test and Wilcoxon signed-rank test were used to determine the statistical differences among the groups.

RESULTS

Syringe administration used in conjunction with lentulo spiral presented lower uncontacted surface area, a lower percentage of uncontacted surface area, larger volume, and a higher percentage of volume than syringe without lentulo spiral (P < 0.05). There was no significant difference between the C-shaped floor group and the non-C-shaped floor group (P > 0.05) in the Ca(OH)2 uncontacted surface area, volume, and percentages at different regions of canals and among different delivery techniques groups.

CONCLUSIONS

The lentulo spiral and syringe technique combination can increase the volume and contacted surface area of Ca(OH)2 in the C-shaped canal system of mandibular second molars.

Assessment of Four Obturation Methods in Deciduous Teeth Using Digital Radiography: An In Vivo Study

Aim and objective

This study was carried out to comparatively assess the efficiency of four methods of obturation viz Lentulo spiral, Navi tip syringe, Bi directional spiral, and Past inject carrier in deciduous teeth using vista scan.

Materials and methods

A total sample of 100 primary root canals [4 groups of 25 canals each] with 2/3^rd of root length were selected and randomly allocated into four different obturating techniques, i.e., Group I: Lentulo spiral, Group II: Navi tip syringe, Group III: Bi directional spiral, and Group IV: Past inject carrier. The quality of obturation [Coll and sadrain, 1996] and presence or absence of voids were evaluated by using Vista scan. The recorded data was statistically analyzed.

Results

The highest mean rank value of optimally filled canals was obtained by Group IV [58.00] followed by Group I [50.00] with no significant difference. The highest mean rank value of under filled canals and over filled canals were obtained by Group III and Group II, respectively, and these results were statistically significant. All the four obturation techniques showed presence of voids with no significant difference.

Conclusion

Both Lentulo spiral and Past inject carrier were equally efficient in attaining an optimally filled homogenous obturation in deciduous teeth.

How to cite this article

Raju SS, Reddy RE, Rani TS, et al. Assessment of Four Obturation Methods in Deciduous Teeth Using Digital Radiography: An In Vivo Study. Int J Clin Pediatr Dent 2022;15(S-1):S52-S56.

Comparison of calcium hydroxide extrusion with syringe versus spiral filler delivery: A pilot study

This study aimed to evaluate Ca(OH)₂ extrusion in relation to delivery technique, apical size and depth of placement. Plastic blocks had j-shaped canals shaped to apical sizes #35 and #45 (n = 32 each). Amounts of calcium hydroxide extrusion was determined relative to apical taper, depth of insertion and whether syringe or spiral filler at 500 rpm was used. Blocks were immersed in pH-sensitive gel and observed for colour change. Extent of extrusion was expressed in mm² . Extrusion occurred in 48/64 of the samples. At 3 mm from the canal terminus, the device affected the frequency of extrusion, with syringe placement causing extrusion significantly (P < 0.01) more frequently, irrespective of apical size. Extrusion was significantly greater at 2 mm short of the canal terminus (median 27.44 mm² ) compared to 3 mm (median 19.69 mm² ). Under in-vitro conditions, a spiral filler at 500 rpm, 3 mm short of the apex, minimised extrusion of Ca(OH)₂ from root canals.

Comparison of Various Root Canal Filling Materials and Obturation Techniques for Primary Teeth Using Microcomputed Tomography

Aim:

The aim of this study was to compare the effectiveness of different filling materials and obturation techniques for root canal obturation in primary teeth.

Materials and Methods:

Eighty maxillary primary incisors were included in this in vitro study. After biomechanical preparation, all samples were scanned using microcomputed tomography (micro-CT) and root canal volumes were calculated. Samples were grouped according to filling materials and obturation techniques, with ten samples in each group. The samples were filled with zinc oxide eugenol (ZOE) and Vitapex using four different obturation techniques (local anesthesia syringe, lentulo spiral, pastinject, and lentulo spiral–ultrasonic activation). After filling, samples were scanned a second time using micro-CT and root canal volumes were calculated. The statistical analysis was performed using SPSS version 24.0. Data were analyzed by Kruskal–Wallis and Mann–Whitney U tests.

Results:

When the ZOE and Vitapex were compared, it was observed that there were no significant differences between their postobturated volumes, percentage obturated volume (POV), internal void (IV), and percentage of internal void volume (PIV) ( P > .05). The local anesthesia syringe group had a significantly lower postobturated volume and POV, and a significantly higher IV and PIV for both filling materials than that by the other groups ( P < .05). There was no significant difference between the other obturation techniques ( P > .05). For the local anesthesia syringe group, postobturated volume and POV were significantly higher and IV and PIV were significantly lower with Vitapex than with ZOE ( P < .05). There was no significant difference between the other obturation techniques filled either with ZOE or Vitapex ( P > .05).

Conclusion:

Except for the syringe technique, no difference was observed between the ZOE and Vitapex materials. The syringe technique used in the primary root canal filling was less effective than the other techniques, which had similar efficacy, and in this technique, more effective canal filling was achieved with Vitapex.

Hardened exogenous material after extrusion of calcium hydroxide with barium sulfate: Case study and histopathologic and laboratory analyses

BACKGROUND AND OVERVIEW

Although calcium hydroxide (Ca[OH]₂) paste associated with barium sulfate (BaSO₄) is considered a safe agent, there is a lack of clinical research on its effects on periodontal and submucosal tissues. The aim of the authors was to report the effects of extrusion of Ultracal XS paste (Ultradent Products) in 2 cases. The authors also analyzed the paste constituents and compared them with the proportion reported by the manufacturer and the material extruded.

CASE DESCRIPTION

The authors present 2 cases in which root canals were restored with Ultracal XS paste after cleaning and shaping, and there was unintentional overextension of the paste into periradicular tissues, with a hardened exogenous material observed associated with inflammatory signs and symptoms. A biopsy was performed, and the material was subjected to histopathologic analysis and characterization through scanning electron microscopy, energy dispersive x-ray spectroscopy, Fourier transform infrared spectroscopy, and x-ray diffraction.

CONCLUSIONS

BaSO₄ and calcium carbonate (CaCO₃) were associated with a hardened material after Ultracal XS paste extrusion. The Ca(OH)₂ percentage on the Ultracal XS paste was approximately 2 times greater than the proportion reported by the manufacturer.

PRACTICAL IMPLICATIONS

Ca(OH)₂ with BaSO₄ paste application should be performed carefully, and its extrusion to periradicular and submucosal tissues should not occur. Its extrusion may result in the formation of a persistent exogenous material of hardened consistency associated with inflammatory signs and symptoms.

Comparative evaluation of three obturation systems in primary molars - A randomized clinical trial

OBJECTIVES

The objective of this study is to evaluate and compare the radiographic efficacy of the quality of obturation and to assess the number of voids and the obturation time in primary teeth using Pastinject™, disposable needle, and capillary tips.

MATERIALS AND METHODS

A total of 34 teeth with 103 canals were randomly divided into three groups using chit method, based on used application: Group 1: Pastinject™ (Micro-Mega, Besancon, France); Group 2: Disposable needle (23G short needle BD Discardit™, Becton Dickinson India Pvt. Ltd.), and Group 3: Capillary tips (Meta Biomed^© Co. Ltd., China). All the groups were named based on obturation systems used. To compare the quality of obturation, the Chi-square test was used; to assess the number of voids, Kruskal-Wallis ANOVA test was used; and to evaluate the obturation time, post hoc Scheffe one-way ANOVA test was used. All P values having <0.05 were considered as statistical significant (P < 0.05). Kappa statistics were performed to check interexaminer reliability. Descriptive statistics were used for evaluation using SPSS (version. 21).

RESULTS

Capillary tips resulted in better optimal filled canals and less obturation time, compared to disposable needle and Pastinject (P < 0.001). There was no significant difference evident among three groups in relation to voids (P = 0.111).

CONCLUSION

Capillary tip technique proved to be the most effective, yielding a higher number of optimally filled canals and minimal voids, combined with easier placement of the material into the canals when compared to Pastinject and disposable needle obturation.

Clinical Assessment of Various Obturating Techniques for Primary Teeth: A Comparative Study

INTRODUCTION

Lifelong preservation of tooth in a healthy state is the ultimate goal of dentistry. Premature loss of primary teeth is common due to caries, dental trauma or other causes. As the primary teeth are the best space maintainers, teeth with infected pulps should be retained until exfoliation, whenever possible.

AIM

The purpose of this in vivo study was to evaluate and compare the efficacy of different obturating methods used in primary teeth.

MATERIALS AND METHODS

Forty one patients aged four to nine years with a total of 60 teeth were selected. Out of the 60 teeth, 32 were primary mandibular first molars and 28 were primary mandibular second molars, the sample was randomly divided into three groups. Disposable syringe, lentulo spiral and past inject were used for obturation. Postoperative evaluation was done for; quality of canal obturation, presence of voids using postoperative radiographs following obturation of teeth. The data were analysed to assess the success rate of the three methods used for obturation using Chi-square test.

RESULTS

Among the three groups of the study, past inject exhibited the maximum number of optimally filled canals. Maximum number of underfilled canals was found with lentulospiral, and the maximum number of overfilled canals was seen with disposable syringe. Least number of voids was observed in canals filled with the past inject technique and disposable syringe.

CONCLUSION

The results suggest that the most successful technique for obturation of primary teeth was past inject.

Evaluation of hydroxyl ion diffusion in dentin and injectable forms and a simple powder-water calcium hydroxide paste: an in vitro study

Background:

Intra canal medicaments are used to reduce the number of bacteria and reinfection in endodontic procedures. Calcium Hydroxide was introduced to endodontics by Herman as an intracanal antimicrobial agent.

Objectives:

The aim of this study was to present an injectable formulation of calcium hydroxide then compare the final pH of this new formulation with Metapaste and evaluate the effect of a mixture of Calcium Hydroxide powder with water on human extracted teeth.

Patients and Methods:

A total of 49 extracted human single-canal roots without caries and visible microcracks were included in this study. The teeth were decoronated and length of teeth was measured 1 mm anatomic apex. The canals were prepared using step-back technique. A cavity was created in the middle third of the buccal surface of all roots. The teeth were randomly divided into five groups: Group A (n = 15): In this group the root canals were filled with a mixture of calcium hydroxide powder and distilled water. Group B (n = 15): Included roots that were filled with Metapaste. Group C (n = 15): Root canals of this group were filled with new formulation of calcium hydroxide paste. Group D (negative control, n = 2): Included roots that were filled with a mixture of calcium hydroxide powder and distilled water. Group E (positive control, n = 2): Root canals of this group were filled with a mixture of calcium hydroxide powder and distilled water. Each tooth was immersed in a separate closed container with 4 mL saline for 2 weeks, pH of liquids were measured with an electrical pH meter after 7 and 14 days. The SPSS software (version 13) was used for data analysis. Analysis of variance (ANOVA) and Tukey tests were used for the statistical evaluation of results.

Results:

There was no significant difference at 7th day between the groups (P = 0.17) but at 14th day, a significant difference was observed between the groups (P = 0.04).

Conclusions:

The new formulation of calcium hydroxide with methylcellulose base has slower ionic dissolution, more durability and longevity of alkaline properties in comparison to combination of powder with distilled water and is comparable with other commercial products.

Intracanal placement of calcium hydroxide: a comparison of specially designed paste carrier technique with other techniques

Background

This study compared the effectiveness of a Specially Designed Paste Carrier technique with the Syringe-Spreader technique and the Syringe-Lentulo spiral technique in the intracanal placement of calcium hydroxide.

Methods

Three groups, each containing 15 single-rooted human anterior teeth were prepared using standardized Mtwo rotary instruments to a master apical file size 40 with 0.04 taper. Each group was filled with calcium hydroxide paste using: Syringe and #25 finger spreader (Group 1); Syringe and #4 rotary Lentulo spiral (Group 2), Specially Designed Paste Carrier (Group 3). Using pre-filling and post-filling radiographs in buccolingual and mesiodistal planes, the radiodensities at 1 mm, 3 mm, 5 mm, and 7 mm from the apical foramen were analyzed by ANOVA and Bonferroni post hoc tests.

Results

Overall, The Specially Designed Paste Carrier technique showed a statistically significantly higher mean radiodensity than the two other compared techniques. No significant difference was detected between the Syringe-Lentulo spiral and the Syringe-Spreader techniques.

Conclusion

The Specially Designed Paste Carrier technique was more effective than the Syringe-Spreader technique and the Syringe-Lentulo spiral technique in the intracanal placement of calcium hydroxide.

Definition and endodontic treatment of dilacerated canals: a survey of Diplomates of the American Board of Endodontics

AIM

To gather data from Diplomates of the American Board of Endodontics regarding treatment of dilacerated canals.

MATERIALS AND METHODS

A questionnaire addressing definition, endodontic treatment procedures and prognosis was constructed and distributed via e-mail to 708 Diplomates of the American Board of Endodontics. Data from 150 respondents, a 21% response rate, were collected by using a Web-based interface. For statistical analysis, Chi-square tests were used.

RESULTS

More than 25% of respondents believed that a dilacerated root should have a curvature > 40°. One-visit treatment is the best therapeutic approach and transportation is the most likely complication in preparation of these canals. A crown-down technique, watch-winding motion and a master apical file # 25 are the best choices for preparation of these canals. Any warm obturation technique is preferred over lateral compaction by most respondents.

CONCLUSION

A crown-down technique for root canal preparation and a thermoplastic obturation technique are recommended for canals whose curvature is more than 40°. The prognosis of the treatment of these canals is judged not lower than normal canals.

CLINICAL SIGNIFICANCE

Crown-down technique and thermoplastic obturation are recommended for dilacerated canals.

Calcium hydroxide inactivates lipoteichoic acid from Enterococcus faecalis

Calcium hydroxide is a widely used endodontic medicament for eliminating viable bacteria and inactivating virulence factors. Enterococcus faecalis, a pathogenic gram-positive bacterium, has been associated with refractory apical periodontitis. Because lipoteichoic acid (LTA) is a major virulence factor of gram-positive bacteria, we examined whether calcium hydroxide could detoxify LTA from E. faecalis. An enzyme-linked immunosorbent assay showed that calcium hydroxide-killed E. faecalis was less potent than heat-killed bacteria in stimulating the release of tumor necrosis factor-alpha by a murine macrophage line, RAW 264.7 (P < 0.05). Pretreatment of LTA with calcium hydroxide remarkably abrogated the ability of LTA to induce the release of tumor necrosis factor-alpha (P < 0.05). Furthermore, calcium hydroxide-treated LTA was not able to stimulate Toll-like receptor 2, which recognizes functionally intact LTA. These results suggest that calcium hydroxide could detoxify LTA, resulting in attenuation of the inflammatory responses to E. faecalis and its LTA.

Influence of calcium hydroxide points on the quality of intracanal dressing filling

Purpose

The aim of this study was to evaluate, in vitro, the quality of calcium hydroxide [Ca(OH)₂] paste filling (Ultracal, Ultradent) associated or not with Ca(OH)₂-containing gutta-percha points (Calcium Hydroxide Plus Points™, Roeko) in curved root canals.

Material and Methods

One hundred and twenty roots of extracted human teeth, randomly divided into three curvature ranges (mild - 0 to 14°; moderate - 15° to 29°; severe - >30°) were used. After chemomechanical preparation, the roots were assigned to 4 groups (n=30), according to the technique of intracanal dressing placement: group 1 - Ca(OH)₂ paste was applied with a lentulo spiral; group 2 - Ca(OH)₂ paste was applied with a lentulo spiral and a Ca(OH)₂ point was inserted into the canal; group 3 - Ca(OH)₂ paste was applied with a Navitip™ tip (supplied with Ultracal system); group 4 - Ca(OH)₂ paste was applied with a Navitip™ tip and a Ca(OH)₂ point was inserted into the canal. The roots were cleared and the quality of apical third filling was assessed by a calibrated experienced examiner. The specimens were examined under stereomicroscopy and scored 1 to 4 (i.e., from inadequate to complete root canal filling). The results were analyzed statistically by ANOVA and Duncan's post hoc test at 5% significance level.

Results

There were no statistically significant differences (p>0.05) among the curvature degrees in groups 1, 3 and 4. Severely curved roots in group 2 presented bordering significance (p=0.05). The groups that associated the use of Ca(OH)₂ paste and points (2 and 4) showed better apical filling than the other groups, but this difference was statistically significant (p<0.001) only for roots with severe curvature.

Conclusion

According to the results of this study, the curvature degree did not influence the quality of filling. The techniques that used Ca(OH)₂-containing gutta-percha points yielded better filling of the apical third in roots with severe curvature.

Calcium hydroxide dressings using different preparation and application modes: density and dissolution by simulated tissue pressure

AIM

To study the effect of different apical shapes in prepared simulated root canals on the application of a commercially prepared calcium hydroxide paste by a syringe or lentulo spiral.

METHODOLOGY

Three different types of root canal preparation were performed in 90 simulated canals: group A to an apical size 20 and a 0.10 taper using hand and rotary instruments, group B to an apical size 30 and a 0.08 taper using GT rotary instruments and group C to an apical size 40 and a 0.04 taper using ProFile 0.04 instruments. The insertion of calcium hydroxide [Ca(OH)2] paste was accomplished using either a lentulo spiral or a syringe. After 1 week of simulated fluid pressure applied to the apical end of the canal using physiological saline solution, the solution was evaluated for released Ca(OH)2. The specimens were weighed initially, after preparation, after insertion of Ca(OH)2 paste, after temporization with Cavit and after 1 week of simulated fluid pressure. Digital radiographs of the filled canals were taken and canal areas in mm2, gray values of the Ca(OH)2 dressings, total area of voids in mm2, as well as location of voids in the apical, middle or coronal thirds of the root canals were measured. Analyses of variance, with Scheffe's post-hoc tests, as well as chi-square tests were performed.

RESULTS

Canals in group C had significantly fewer (P < 0.01) radiographic voids than canals in groups A and B. Using a lentulo spiral resulted in significantly (P < 0.05) fewer voids compared with the injection technique. More voids were detected coronally compared with middle and apical root canal thirds (P < 0.05).

CONCLUSIONS

Canal shape and method of application had an impact on the amount and radiodensity of calcium hydroxide dressings in simulated root canals. Canals prepared to an apical size 40 and a taper of 0.04 had the least number of voids; Ca(OH)2 was placed with significantly fewer voids using a lentulo spiral compared with the injection technique.

Growth at high pH increases Enterococcus faecalis adhesion to collagen

AIM

To evaluate the effect of growth at pH levels from 7.1 to 9.5 on the adherence of Enterococcus faecalis to bovine serum albumin (BSA) and collagen type I.

METHODOLOGY

Enterococcus faecalis strain A197A was grown in broth of adjusted pHs varying between 7.1 and 9.5. Aliquots of bacterial suspensions were added to wells coated either with BSA or with collagen type I. Bacteria adhering to the surfaces were stained with crystal violet. Spectrophotometric measurements of the dissolved stain were used to assess the number of bacteria adhering to the surfaces. The data obtained were analysed using the Kolmogorov-Smirnov test, Levene's test and Student's t-test, with alpha = 0.05 as the level for statistical significance.

RESULTS

The adhesion of E. faecalis to BSA-coated surfaces decreased inversely with alkalinity of the growth medium. The pH 7.1-grown bacteria bound to BSA significantly more than the other BSA groups. On the contrary, the adhesion to collagen type I-coated surfaces of bacteria grown at pH 8.0 and 8.5 was significantly greater than for those grown at pH 7.1.

CONCLUSIONS

A minor increase in pH up to 8.5, which may be a consequence of insufficient treatment with alkaline medicaments such as calcium hydroxide, increases the collagen-binding ability of E. faecalis, in vitro. This can be a critical mechanism by which E. faecalis predominates in persistent endodontic infections.

Intracanal Placement of Calcium Hydroxide: A Comparison of Techniques, Revisited

The goal of this in vitro study was to compare the effectiveness of three different placement techniques of calcium hydroxide paste in a curved canal. An acrylic resin block with a 44-degree curvature was instrumented to a #40 Flex-R file. The canal was filled with radiopaque calcium hydroxide paste using the following techniques: group 1, the paste was injected with an Ultradent tip; group 2, the paste was injected as in group 1 and followed by a size 35 Lentulo to working length; and group 3, the paste was placed with a size 35 Lentulo only, to working length. Each technique was performed 25 times. The radiodensity of the simulated canal was measured at 1, 3, 5, and 7 mm from the canal terminus. At 1 mm, the Lentulo was significantly better than the other two techniques. At 3 mm, the Lentulo technique and the combined technique were better than the Ultradent tip alone.

Effects of calcium hydroxide paste medication on coronal leakage

The purpose of this in vitro study was to examine the coronal leakage of canals medicated with Ca(OH)(2) compared with the canals which did not receive Ca(OH)(2) medication before obturation with laterally condensed gutta-percha points and sealer. Sixty-one single rooted permanent canines and premolars were used. The crowns were removed from the cemento-enamel junction. After the canals were chemomechanically prepared, the roots were divided into three experimental groups as group 1, 2 and 3. The canals in group 1 and 2 were treated with ethylenediaminetetraacetic acid (EDTA) and NaOCl in order to remove the smear layer and then the canals were filled with Ca(OH)(2) paste. The coronal 3 mm of the cavities were sealed with Cavit and the samples were kept in an incubator at 37 degrees C for 7 days. No intra-canal medication was applied in group 3. The root canals were irrigated with NaOCl in group 1 and with EDTA and NaOCl in group 2, in order to remove Ca(OH)(2) before obturation. Two samples from group 1 and two from group 2 were examined under SEM in order to reveal the removal of Ca(OH)(2) paste. Following this, the canals in the experimental groups were obturated with gutta-percha and sealer. The roots were placed in India ink for 7 days and the linear dye penetration was evaluated. No significant statistical difference was found in the amount of coronal dye leakage between experimental groups (P > 0.05). The results of the present study indicated that the application of Ca(OH)(2) as a temporary dressing material had no effect on coronal leakage.

Intracanal placement of calcium hydroxide: a comparison of two different mixtures and carriers

Objective. The purpose of this study was to compare the placement techniques of Ca(OH)(2). Study Design. Forty simulated curved canals (42 degrees) in transparent resin blocks were used and separated into 4 experimental groups, 10 canals each. A paste of Ca(OH)(2) was mixed with either water or glycerin and placed into canals with Lentulo spiral or Pastinject. Radiographs were taken of each sample. The canal fillings were evaluated by 3 endodontists and scored as to length of placement and completeness of fill. Cohen's kappa test was used to measure agreement between raters, and Kruskal-Wallis analysis of variance test was used to determine statistical differences between the 4 groups. Results. As to length of placement, statistically significant differences were found between Ca(OH)(2) + water pastes filled with Lentulo spiral (group 1) and Ca(OH)(2) + glycerin pastes filled with either Pastinject or Lentulo spiral. The findings of group 1 showed that the paste was short of the apex by more than 2 mm, whereas the other 3 groups were either at the apex or only 1 to 2 mm short. As to middle and coronal completeness of fill, differences were found to be statistically significant between Ca(OH)(2) + water paste filled with Lentulo spiral group and the other groups. Most of the canals in group 1 had greater than one-half void space at apical third, whereas the canals had less than one-fourth void space when Ca(OH)(2) + glycerin pastes were filled with Pastinject. Conclusions. Ca(OH)(2) when mixed with glycerin and placed into the canals, either with a Lentulo spiral or Pastinject, provided satisfactory results. Pastinject showed better fillings with Ca(OH)(2) + water pastes than Lentulo spiral.