Dentin penetrability evaluation of three different dyes in root-end cavities filled with mineral trioxide aggregate (MTA)

Comparative Evaluation of the Sealing Ability of Mineral Trioxide Aggregate (MTA)-Based, Resin-Based, and Zinc Oxide Eugenol Root Canal Sealers: An In Vitro Study

Root canal therapy is a crucial procedure in endodontics that is done to achieve complete obliteration of the root canal space. The success of this therapy depends on achieving a proper seal, which is facilitated using root canal sealers. This study aimed to compare the apical sealing ability of three different root canal sealers: MTA Fillapex, AH Plus, and zinc oxide eugenol (ZOE), using the dye penetration method. Forty freshly extracted single-rooted human maxillary incisors were collected and prepared for the study. The root canals were instrumented using the ProTaper system, and the canals were then obturated using the lateral condensation technique with the respective sealers. After one week of storage, the samples were coated with nail varnish, immersed in a rhodamine B dye solution, and then sectioned longitudinally. The depth of dye penetration was measured, and the results were analyzed statistically. The results revealed significant differences in apical leakage among the three experimental groups. Group 2 (AH Plus) showed the minimum leakage with a mean of 0.13 mm, while Group 4 (no sealer) exhibited the maximum leakage with a mean of 4.49 mm. Group 3 (ZOE) showed an intermediate level of leakage with a mean of 2.37 mm. The statistical analysis confirmed the significant difference in mean leakage among the groups. The findings of this study indicate that AH Plus exhibited superior apical sealing ability compared to MTA Fillapex and ZOE. AH Plus is a resin-based sealer known for its dimensional stability. On the other hand, MTA Fillapex, a newly introduced sealer containing mineral trioxide aggregate, resin, and silica, showed promising sealing properties but had slightly higher leakage compared to AH Plus. ZOE, a traditional sealer, demonstrated relatively higher leakage than the other sealers. In conclusion, choosing a root canal sealer is crucial in achieving a successful endodontic treatment outcome. AH Plus demonstrated superior apical sealing ability among the three sealers tested. Further research and long-term clinical studies are warranted to validate these findings and assess the impact of sealer choice on treatment outcomes and post-endodontic healing.

Evaluation of the Sealing Ability and Bond Strength of Two Endodontic Root Canal Sealers: An In Vitro Study

BACKGROUND

Obturation represents a critical step in endodontic treatment, which relies on a core material and a sealer. This study aims to evaluate the sealing ability and bond strength to the root canal walls of an epoxy resin-based sealer (AH-Plus®, Dentsply Sirona, Johnson City, TN, USA) and a bioceramic sealer (GuttaFlow Bioseal®, Coltène/Whaledent, GmbH + Co. KG, Langenau, Germany).

METHODS

Thirty-eight maxillary anterior teeth with single roots and identical round sections were separated into two experimental groups according to the root canal sealers used, namely, G1 = AH-Plus® and G2 = GuttaFlow Bioseal®, and two control groups, specifically, G3 = the negative control and G4 = the positive control. The sealing capacity was measured by the penetration of the radioactive isotope 99mTc. For the push-out test, the compressive force test was performed in a universal machine and the force was applied by exerting pressure on the surface of the material to be tested in the apical to the coronal direction and using three test points with different diameters.

RESULTS

GuttaFlow Bioseal® exhibited superior sealing ability compared to AH-Plus® (p = 0.003). Regarding the bond strength, AH-Plus® provided higher adhesion values than GuttaFlow Bioseal® in the three sections of the tooth root (p = 0.001).

CONCLUSIONS

GuttaFlow Bioseal® had significantly better sealing ability than AH-Plus® but lower adhesion values in the three zones of the root canal, with statistically significant differences between the groups. However, it is important to note that for the action of endodontic sealers to be maximized, the root-filling technique must be most appropriate.

Value addition property of a cationic surfactant on endodontic irrigant: A confocal laser scanning microscope study

Introduction:

Chlorhexidine (CHX) is a commonly used root canal irrigant with high surface tension which prevents its penetration into the isthmus and fins of the root canal. Surfactants have known to reduce the surface tension of the liquid. Cetylpyridinium chloride (CPC) is a cationic surfactant. The aim of this study is to assess the contact angle formed and depth of penetration of the endodontic irrigant with and without the addition of surfactant.

Methods:

Contact angle analysis – Ninety-nine freshly extracted and cleaned single-rooted mandibular premolars were obtained. Thirty-three teeth were sectioned longitudinally and then transversely. The sections were mounted on an acrylic block, polished to obtain a flat dentin surface. Five microliter of Group 1: 2% CHX as control, Group 2: 2% CHX + 0.1% CPC, and Group 3: 2% CHX + 0.2% CPC were placed on the dentin surface and subjected to contact angle analysis. Depth of penetration – Access cavity was prepared in sixty-six teeth and instrumented to working length till Protaper Gold F2. The samples were assigned to Groups 1, 2, and 3 and irrigated accordingly, and subjected to a confocal laser scanning Microscopy. Data were analyzed using one-way ANOVA and Tukey multiple comparison test. Karl Pearson's correlation test was performed to analyze the correlation between the two.

Results:

Group 3 had the lowest contact angle (12.82°) and the highest depth of penetration (222.74 μm) when compared to Group 1 and Group 2. Karl Pearson's correlation showed no correlation between the contact angle and the depth of penetration.

Conclusion:

Higher the concentration of CPC, lower is the contact angle formed with the dentin and higher is the depth of penetration into the dentinal tubule.

Is Gutta-Percha Still the “Gold Standard” among Filling Materials in Endodontic Treatment?

The paper is an extensive monographic review of the literature, and also uses the results of the authors’ own experimental research illustrating the noticed developmental tendencies of the filling material based on gutta-percha. The whole body of literature proves the correctness of the research thesis that this material is the best currently that can be used in endodontics. Caries is one of the most common global infectious diseases. Since the dawn of humankind, the consequence of the disease has been the loss of dentition over time through dental extractions. Both tooth caries and tooth loss cause numerous complications and systemic diseases, which have a serious impact on insurance systems and on the well-being, quality, and length of human life. Endodontic treatment, which has been developing since 1836, is an alternative to tooth extraction. Based on an extensive literature review, the methodology of qualifying patients for endodontic treatment was analyzed. The importance of selecting filling material and techniques for the development and obturation of the root canal during endodontic treatment was described. Particular attention was paid to the materials science aspects and the sequence of phase transformations and precipitation processes, as well as the need to ensure the stoichiometric chemical composition of Ni–Ti alloys, and the vacuum metallurgical processes and material processing technologies for the effects of shape memory and superelasticity, which determine the suitability of tools made of this alloy for endodontic purposes. The phenomena accompanying the sterilization of such tools, limiting the relatively small number of times of their use, play an important role. The methods of root canal preparation and obturation methods through cold side condensation and thermoplastic methods, including the most modern of them, the thermo-hydraulic condensation (THC) technique, were analyzed. An important element of the research hypothesis was to prove the assumption that to optimize the technology of development and obturation of root canals, tests of filling effectiveness are identified by the density and size of the gaps between the root canal wall, and the filling methods used and devices appropriate for material research, using mainly microscopy such as light stereoscopic (LSM) and scanning electron (SEM). The most beneficial preparations were obtained by making a longitudinal breakthrough of 48 natural human teeth, extracted for medical reasons, different from caries, with compliance with all ethical principles in this field. The teeth were prepared using various methods and filled with multiple obturation techniques, using a virtual selection of experimental variants. The breakthroughs were made in liquid nitrogen after a one-sided incision with a narrow gap created by a diamond disc using a materialographic cutter. The best effectiveness of the root canal filling was ensured by the technology of preparing the root canals with K3 rotary nitinol tools and filling the teeth with the THC thermoplastic method using the System B and Obtura III devices with studs and pellets of filling material based on gutta-percha after covering the root canal walls with a thin layer of AH Plus sealant. In this way, the research thesis was confirmed.

The Effect of Root End Cavity Preparation Using Er,Cr:YSGG Laser, Ultrasonic Retrotip, and Bur on the Apical Microleakage of Retrograde Cavity Filled with MTA Plus

Aim:

The sealing ability of the retrograde material is greatly affected by the technique used for root end preparation. Advances in retrograde preparation techniques such as lasers has shown to provide an efficient outcome. The study was to evaluate and compare the effect of various techniques of retrograde cavity preparation on apical microleakage.

Materials and Methods:

Forty-five single rooted teeth were decoronated. Biomechanical preparation was carried out up to size F2 ProTaper system and obturated. Glass–ionomer cement was used as an access restorative material. The apical root resection was done at 3 mm from the apex at angulation of 90° to the long axis of the root. The allocation of the samples was done into three groups of 15 each. Group A: Retrograde cavities prepared using conventional round bur; Group B: Retrograde cavities prepared using ultrasonic retro preparation diamond tip; and Group C: Retrograde cavities prepared using “Erbium, chromium: yttrium, scandium, gallium, garnet” (Er,Cr:YSGG). The retrograde cavities hence prepared were filled with MTA Plus. Nail varnish was used to coat the samples except at the apical end. Samples were immersed in methylene blue for 24h. Stereomicroscope was used for examination of the sectioned teeth. The data were analyzed using one-way analysis of variance (ANOVA) and post hoc Tukey test.

Results:

Results showed very highly significant difference between laser and bur (P value = 0.001).

Conclusion:

Retrograde preparation with Er,Cr:YSGG showed significantly less microleakage when compared to the use of ultrasonic retrotip and burs.

Apical Microleakage in Root Canals Containing Broken Rotary Instruments

INTRODUCTION

Broken instruments in root canals complicate routine endodontic treatment. This study aimed to compare apical microleakage in root canals containing broken rotary instruments filled with mineral trioxide aggregate (MTA), calcium-enriched mixture (CEM) cement, laterally compacted gutta-percha and injected gutta-percha.

METHODS AND MATERIALS

In this in vitro, experimental study, 80 extracted human premolars were decoronated and then the roots were randomly divided into four groups (n=20). Root canals were instrumented with Mtwo rotary files. The files were scratched 3 mm from the tip by a high speed handpiece and they were intentionally broken in the apical third of the canals. The middle and coronal thirds of the canals were then filled with MTA, CEM cement, gutta-percha with lateral compaction technique and injected gutta-percha. Apical microleakage was measured using dye penetration method. Data were analyzed using ANOVA and Tukey's test.

RESULTS

Root canals filled with CEM cement showed the lowest and those filled with injected gutta-percha showed the highest microleakage according to dye penetration depth. No significant difference was noted between the microleakage of CEM cement and MTA or between lateral compaction of gutta-percha and injected gutta-percha (P>0.05). However, CEM cement and MTA groups had significantly lower microleakage than laterally compacted and injected gutta-percha groups (P<0.05).

CONCLUSION

Due to their superior sealing ability, MTA and CEM cement are suitable for filling of root canals containing a broken instrument compared to laterally compacted and injected gutta-percha.

Sealing ability of MTA and amalgam in different root-end preparations and resection bevel angles: an in vitro evaluation using marginal dye leakage

This in vitro study evaluated the effect of different apicoectomy angles, instruments used in root-end preparation, and dental materials used in retrofilling on apical sealing. Root ends were resected at 45 or 90 degrees in 80 single-rooted teeth. For each type of apicoectomy, root-end cavities were prepared with either a round carbide #2 bur or an S12/90D ultrasonic tip. The root-end cavities in each subgroup (apicoectomy + root-end preparation) were filled with silver amalgam without zinc (Am) or with gray mineral trioxide aggregate -Angelus (MTA), and the specimens were immediately immersed in 0.2% rhodamine B for 24 h. Sealing was evaluated based on the dyed cross-sectional dentin area. Data were analyzed statistically by the Kruskal-Wallis test at 5% significance level. No group showed complete sealing of root-end areas. The only significant factor affecting microleakage was dental material, with MTA exhibiting less leakage.

Assessment of different dyes used in leakage studies

The goal of this in vitro study was to identify the most suitable dye for endodontic dye leakage studies, which could be a further step towards standardisation. The root canals of 70 extracted, single-rooted human adult teeth were enlarged to apical size 50 using hand instruments. The teeth were divided into seven groups (n = 10 each), and all root canals were completely filled by injection with one of the following dyes: methylene blue 0.5% and 5%, blue ink, black ink, eosin 5%, basic fuchsin 0.5% and drawing ink. Transverse root sections from the coronal, middle and apical part of the roots were examined, and the percentage of the dentine penetrated by dye was evaluated by software-supported light microscopy. In addition, the range of particle size of drawing ink particles was evaluated. There were conspicuous differences in the relative dye penetration into the root dentine and the penetration behaviour in the different root sections (two-way ANOVA, both p < 0.0001). One dye (drawing ink) penetrated less into the root dentine compared with all the others (p <0.0001). The particle size of this agent (0.1-2 microm) corresponds best with the size range of a representative selection of 21 species of pathogenic endodontic bacteria. Compared to the other dyes tested, drawing ink appears to be superior for use in endodontic dye leakage studies. The penetration behaviour into the root dentine of all the other dyes tested might be one factor that limits the applicability of these dyes in dye leakage studies.