Correlation between clinical success and apical dye penetration

Sealing ability of various endodontic sealers with or without ethylenediaminetetraacetic acid (EDTA) treatment on bovine root canal

This study investigated the wettability and consistency of various endodontic sealers, both inorganic and organic, and evaluated their sealing ability of root canals using the single-cone obturation technique, with and without ethylenediaminetetraacetic acid (EDTA) treatment. Bovine root canals were endodontically prepared and filled in preparation for the dye penetration test with toluidine blue solution. All sealers exhibited contact angles similar to or lower than dentin and displayed superior consistency. Among the sealers, organic sealers used without EDTA treatment showed reduced dye penetration compared to inorganic sealers. However, some inorganic and organic sealers showed dye penetration in the sealer and dentin of root canals subjected to EDTA treatment. In conclusion, the single-cone obturation technique, combined with these endodontic sealers, achieved close contact with root canal dentin due to their wettability and consistency. However, the sealing ability of certain sealers was influenced by EDTA treatment.

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.

Methodologies used for testing the sealability of endodontic temporary fillings in vitro: A narrative review

Introduction

The ability of the temporary filling to seal endodontic access cavities may be crucial for the success of endodontic treatment. Numerous in vitro studies have investigated the sealability of the temporary fillings used in endodontic treatments. However, in vitro sealability studies have been criticized for their inconsistent results and questionable clinical relevance. Some journals have imposed moratoriums on publishing such studies to encourage researchers to test their validity and clinical relevance. Since the implementation of this moratorium, little progress has been made in this field. To further encourage researchers to investigate the reliability of these studies, this review presents an overview of the methodologies of studies that examine the ability of temporary filling materials to seal the endodontic access cavity in vitro and discusses the criticisms of these studies in detail.

Materials and Methods

PubMed, Scopus, and Embase electronic databases were searched to identify studies that tested in vitro the ability of temporary filling materials to seal endodontic access cavities. Only original articles published in English between 01/01/1970 and 28/02/2022 were included.

Results

The search yielded 551 results. After removing duplicates and excluding studies that did not meet the inclusion criteria, 94 studies were included in this review.

Conclusion

Although clinical studies may be the best way to test the performance of temporary fillings, the ethical importance of conducting preliminary in vitro studies is undeniable. It seems that questioning the reliability of in vitro sealability studies is not based on sufficient scientific evidence and that the inconsistencies in the results of these studies may be due to differences in the methodological and clinically relevant variables between them, rather than due to their unreliability.

Bacterial leakage assessment in root canals sealed with AH Plus sealer modified with silver nanoparticles

BACKGROUND

Successful endodontic therapy requires prevention of bacterial leakage between the root canal filing and root-canal walls. Sealing quality of a root canal filling depends strongly on the sealing ability of the sealer used. The present study aimed to evaluate the bacterial leakage resistance of AH Plus sealer modified with silver nanoparticles.

METHODS

Forty sound teeth were obturated using lateral compaction technique except for five teeth as the negative controls. After considering five teeth as the positive controls (filled without sealer), the remaining teeth were assigned to two groups (n = 15) in terms of the sealer used (AH Plus sealer and silver nanoparticle-modified AH Plus). Bacterial leakage was evaluated in saliva using the two-chamber technique in every 24 h. When all the samples in the test groups were contaminated, the study was terminated. The data were analyzed with log-rank statistical test.

RESULTS

All samples in both experimental groups were contaminated during the 3-months period of observation. There was no significant difference in contamination time between study groups (P > 0.05).

CONCLUSIONS

Silver nanoparticles used in tested concentration did not improve the bacterial leakage resistance of AH Plus sealer.

Efficacy of MTA Modified by Nanosilver for the Prevention of Coronal Leakage

Background:

Numerous materials have been introduced as coronal barriers, however, they have shown various degrees of microleakage. Therefore, attempts are undertaken to introduce more reliable materials with the potential to provide a long-term coronal seal.

Introduction:

This in vitro study aimed to assess the efficacy of gray ProRoot Mineral Trioxide Aggregate (MTA) modified by a suspension of silver nanoparticles (AgNPs) as an orifice plug using a bacterial leakage method.

Methods:

40 extracted human teeth were prepared and filled (except for the negative control group) using the lateral compaction technique. The coronal 2 mm of the root filling was removed in the experimental groups. The teeth were randomly divided into two experimental (n = 15) and two control (n = 5) groups. In the experimental group 1 (MTA group) and the experimental group 2 (Ag-MTA group), MTA modified by a suspension of AgNPs was used as an orifice plug. In the negative control group, the entire root surfaces were covered with two layers of nail varnish. In the positive control group, the root canals were filled with a single gutta-percha cone without a sealer and no orifice plug. Bacterial leakage was assessed using a two-chamber system. The teeth were incubated at 37°C and 100% humidity for 120 days, and human saliva was added to the samples every 3 days. Bacterial microleakage was assessed by daily monitoring and observating the turbidity of the Brain Heart Infusion (BHI) broth. The data were analyzed using the log-rank test.

Results:

All positive controls showed contamination after 5 days. None of the negative controls were contaminated during the experiment. The Ag-MTA group demonstrated a significantly better coronal seal than the MTA group (p = 0.031).

Conclusion:

Gray ProRoot MTA modified by AgNPs has the potential for being used as an orifice plug in endodontically treated teeth.

Comparative evaluation of microleakage after root-end resection by erbium, chromium: Yttrium-scandium-gallium-garnet (Er, Cr:YSGG) laser and carbide bur with or without placement of mineral trioxide aggregate: An in vitro study

Background:

Root-end resection followed by retrofilling is one of the prime requisites to avoid apical microleakage.

Aim:

It comparatively evaluated the microleakage after root-end resection by erbium, chromium:yttrium, scandium, gallium, and garnet laser and carbide bur with or without placement of mineral trioxide aggregate (MTA).

Materials and Methods:

In this study, 60 maxillary central incisors were decoronated and biomechanically prepared. Out of 60 samples, 48 were included in the experimental group while the rest 12 were in the control group. The samples in the experimental group were obturated, whereas the samples in the control group were not obturated. The experimental group samples were divided into two: one group resected with the laser and the other half resected with carbide bur. These groups were further subdivided into two – one group retrofilled with MTA and the other half without MTA. The control group had both laser- and carbide bur-resected samples with positive and negative controls. All the samples were dyed, decalcified, and cleared. Digital photograph of each sample was taken, and the area of dye penetration was measured with the help of ImageJ software.

Statistical Analysis:

Analysis of variance and Tukey's test were done.

Results:

The highest microleakage was seen in carbide without MTA and the least was seen with laser with MTA.

Conclusion:

Laser-resected MTA-retrofilled samples showed minimum leakage.

Evaluation of the sealing ability of different root canal sealers: a combined SEM and micro-CT study

Objective

The purpose of this study was to analyze the ability of multiple compounds to seal the dental tubules using scanning electron microscopy (SEM) and micro-computed tomogra-phy (micro-CT).

Material and Methods

Twenty-four single-root human mandibular premolars were selected and instrumented with nickel-titanium rotary file and the final file size was #40/06. They were then randomly allocated into 2 groups, and all samples were filled with single cone gutta-percha (#40/06) and one of the tested sealers (AH Plus and EndoSequence BC sealers). All specimens were scanned using micro-CT and then three from each group were randomly selected for SEM analysis.

Results

According to SEM, both root canal sealers showed sufficient adaptation to dentin along the whole length of the root canal, though the coronal sections presented superior sealing than the apical sections. Micro porosity analyses revealed that the volume of closed pores and the surface of closed pores had the largest values in the coronal sections, followed by the middle and the apical sections for both sealants (p<0.05). However, no significant difference was observed for those two parameters between AH Plus and EndoSequence BC sealers in any of the three sections (p>0.05), whereas they were larger in the apical section when the AH Plus sealer was used.

Conclusions

By using the single cone technique, neither EndoSequence or AH Plus pro-vides a porosity-free root canal filling. The EndoSequence BC sealer may have similar sealing abilities regarding the whole root canal as the AH Plus sealer. A better sealing effect could be obtained in the coronal and middle sections of a root canal than the apical part by using the tested sealers.

The Repair of Furcal Perforations in Different Diameters with Biodentine, MTA, and IRM Repair Materials: A Laboratory Study Using an E. Faecalis Leakage Model

The aim of this study is to evaluate the microleakage of repair materials MTA, IRM, and Biodentine applied on furcal perforations with different diameters. One hundred and forty extracted human teeth were used in this study. The teeth were divided into 2 main groups (60 teeth in each) which were then divided into 3 subgroups (n = 20). The remaining 20 teeth were divided into 2 groups (10 in each) to serve as controls. The furcal areas of the teeth were perforated with #2 cylindrical burs in Group 1 whereas perforations were made using #4 cylindrical burs in Group 2. Each subgroup of both Groups 1 and 2 received ProRoot MTA (ProRoot, USA), Biodentine (Septodont), or IRM (Dentsply, USA) to repair the perforations. An experimental set-up was established to contaminate repaired perforations with E. Faecalis (ATCC29212). The turbidity of bacteria was observed on the 7th, 15th, 30th, and 45th days. The data was analysed by chi-square test (p > 0.05). The number of bacteria in the group perforated by bur #2 and closed by MTA was found to be lower than the other groups on the 7th day (p < 0.05). There was no statistical difference in the bacterial counts of other groups on the 15th, 30th, and 45th days (p > 0.05). ProRoot MTA was found to be more successful in the prevention of bacterial leakage compared to IRM and Biodentine in smaller perforations during the 1st week.

Apical dye leakage of two single-cone root canal core materials (hydrophilic core material and gutta-percha) sealed by different types of endodontic sealers: An in vitro study

Aim of the Study:

The aim of this study was to compare the apical sealing ability of two single-cone filling materials when sealed with different types of root canal sealers.

Materials and Methods:

Eighty extracted maxillary and mandibular canines were selected and their crowns were cut. The root canals were prepared using ProTaper Universal rotary system until size F4 and then divided into seven experimental groups (n = 10 each) and two control groups (n = 5 each). Samples of Groups 1, 2, and 3 were filled with single-cone gutta-percha and AH Plus, MTA Fillapex, and EndoSequence BC, respectively. Samples of Groups 4, 5, and 6 were filled similar to the previous groups with the exception of using a single-cone CPoint. Samples of Group 7 were filled with cold gutta-percha lateral condensation technique. To assess apical microleakage, the apical linear dye penetration was measured microscopically and data were statistically analyzed.

Results:

All experimental groups showed significantly different dye apical leakage values (P = 0.000). No significant differences were found between Groups 1, 2, 4, 6, and 7 (P < 0.05). The lowest mean leakage value was observed in Group 6 (0.95 ± 0.56 mm) while Groups 3 (2.68 ± 0.71 mm) and 5 (2.61 ± 0.71 mm) showed significantly higher mean leakage values.

Conclusions:

The lowest apical leakage value was observed with single-cone CPoint/EndoSequence BC but without significant differences when compared with single-cone gutta-percha/AH Plus, single-cone gutta-percha/MTA Fillapex, single-cone CPoint/AH Plus, and lateral condensation technique. Higher apical leakage values were observed with single-cone gutta-percha/EndoSequence BC and CPoint/MTA Fillapex.

Apical Microleakage in Root Canals Obturated With 2 Different Endodontic Sealer Systems in Canine Teeth of Dogs

An apical dye leakage test was utilized to compare 2 endodontic sealer systems commonly used in veterinary endodontic treatment. Rotary instrumentation followed by injection of 2 different sealers (GuttaFlow 2 and AH Plus) and a single master cone obturation technique were compared. Following obturation and restoration, specimens were immersed in India ink for 48 hours. A tooth mineral clearing technique was utilized to render the tooth samples transparent. Subsequently, the apices were evaluated for prevalence and magnitude of apical dye penetration under magnification. Statistical analysis of the results revealed no significant differences in the prevalence or magnitude of apical dye penetration between groups.

Evaluation of the Sealing Ability of Three Obturation Techniques Using a Glucose Leakage Test

The aim of this study was to evaluate the sealing ability of three different canal filling techniques. Sixty-four roots of extracted human maxillary anterior teeth were prepared using ProTaper® rotary instruments. The specimens were then randomly divided into 3 experimental groups (n = 16) and 2 control groups (n = 8). The root canals were filled using cold lateral compaction (CLC group), continuous wave condensation technique using the Elements Obturation Unit® (EOU group), and ProTaper obturators (PT group). For the negative control group, 8 roots were filled using lateral compaction as in the CLC group, and the teeth were covered twice with a layer of nail varnish (NCG group). Another 8 roots were filled using lateral compaction, but without sealer, and these were used as the positive control (PCG group). A glucose leakage model was used for quantitative evaluation of microleakage for 24 hours and 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 weeks. No significant difference in the cumulative amount of leakage was found between the three experimental groups at all observation times. The lateral condensation of cold gutta-percha can guarantee a similar seal of canal fillings as can be achieved by using thermal methods, in the round canals.

Volumetric Evaluation of Different Obturation Techniques in Primary Teeth Using Spiral Computed Tomography

BACKGROUND

Various obturation techniques have been evaluated for better filling of the root canals in primary teeth using different methods. Spiral Computed Tomography (SCT) is a new revolution in the pediatric endodontics for assessment of quality of the obturation from 3 dimensions.

OBJECTIVES

To evaluate the efficiency of 5 different obturation methods in delivering the filling material into the canals of primary teeth using Spiral Computed Tomography scan.

STUDY DESIGN

A total of 50 canals of primary teeth were prepared, divided into 5 groups with 10 canals in each group and obturated with Zinc Oxide Eugenol cement using 5 different obturation techniques such as Local anesthetic syringe, Tuberculin syringe, Endodontic plugger, hand held Lentulo-spiral, and Lentulo-spiral mounted on slow speed hand piece. The pre and post obturation volume and finally the Percentage of Obturated Volume (POV) were calculated using SCT scan for each group. The data obtained was statistically analyzed using One-way Analysis of Variance (ANOVA) and Tukey's post-hoc test.

RESULTS

Lentulo-spiral hand held showed highest POV value followed by Lentulospiral mounted to hand piece, Tuberculin syringe and Endodontic plugger; whereas Anesthetic syringe had least POV (P < 0.05).

CONCLUSION

Lentulo-spiral hand held is the best obturating technique among the 5 groups evaluated as the canals of this group showed maximum percentage of filled material. However, a further study with large sample size is highly essential.

In vitro evaluation of a newly produced resin-based endodontic sealer

OBJECTIVES

A variety of root canal sealers were recently launched to the market. This study evaluated physicochemical properties, biocompatibility, and sealing ability of a newly launched resin-based sealer (Dia-Proseal, Diadent) compared to the existing root canal sealers (AHplus, Dentsply DeTrey and ADseal, Metabiomed).

MATERIALS AND METHODS

The physicochemical properties of the tested sealers including pH, solubility, dimensional change, and radiopacity were evaluated. Biocompatibility was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. For microleakage test, single-rooted teeth were instrumented, and obturated with gutta-percha and one of the sealers (n = 10). After immersion in 1% methylene blue solution for 2 weeks, the specimens were split longitudinally. Then, the maximum length of staining was measured. Statistical analysis was performed by one-way analysis of variance followed by Tukey test (p = 0.05).

RESULTS

Dia-Proseal showed the highest pH value among the tested sealers (p < 0.05). ADseal showed higher dimensional change compared to AHplus and Dia-Proseal (p < 0.05). The solubility values of AHplus and Dia-Proseal were similar, whereas ADseal had the lowest solubility value (p < 0.05). The flow values of sealer in increasing order were AHplus, DiaProseal, and ADseal (p < 0.05). The radiopacity of AHplus was higher than those of ADseal and Dia-Proseal (p < 0.05). The cell viability of the tested materials was statistically similar throughout the experimental period. There were no significant differences in microleakage values among the tested samples.

CONCLUSIONS

The present study indicates that Dia-Proseal has acceptable physicochemical properties, biocompatibility, and sealing ability.

Quantitative microleakage analysis of root canal filling materials in single-rooted canals

The purpose of this study was to analyze the sealing ability of different root canal filling materials over a 6-week period using a glucose penetration model. Forty-six recently extracted human premolars were used in this study. The root canals were enlarged to 40/0.06. Prepared canals were randomly assigned into four groups (n = 10) as follows: Group 1, Gutta-Percha (GP)/AH Plus with cold lateral compaction; Group 2, GP/AH Plus with continuous wave compaction; Group 3, RealSeal SE obturation system; and Group 4, OrthoMTA. The remaining specimens were used as positive and negative controls, and all specimens underwent thermocycling (10,000; 5-55 °C). The sealing ability of all samples was evaluated at 24 h, 1, 2, 4, and 6 weeks using a quantitative glucose leakage model, and scanning electron microscope (SEM) images were taken. A mixed effect analysis using R statistical language was performed. Groups 1, 2, and 4 showed low leakage levels during experimental periods. Group 3 showed low leakage levels for the first 2 weeks; however, the leakage level was significantly increased after 2 weeks compared to negative control group (p < 0.05). In the SEM results, Group 3 showed imperfect dentin bonding, whereas Group 4 showed calcium silicate hydrate short tags, which are formed at the access of the dentin tubules. GP/AH Plus and OrthoMTA showed less microleakage than RealSeal SE obturation system when used as root canal filling materials. Traditional GP/AH Plus sealer and the newly developed OrthoMTA are more appropriate for ideal sealing of the root canals.

Quantitative microleakage analysis of endodontic temporary filling materials using a glucose penetration model

OBJECTIVE

The purpose of this study was to analyze the sealing ability of different temporary endodontic materials over a 6-week period using a glucose penetration model.

MATERIALS AND METHODS

Standardized holes were formed on 48 dentin discs from human premolars. The thicknesses of the specimens were distributed evenly to 2 mm, 3 mm and 4 mm. Prepared dentin specimens were randomly assigned into six groups (n = 7) and the holes in the dentin specimens were filled with two kinds of temporary filling materials as per the manufacturers' instructions as follows: Caviton (GC Corporation, Tokyo, Japan) 2 mm, 3 mm, 4 mm and IRM (Dentsply International Inc., Milford, DE) 2 mm, 3 mm, 4 mm. The remaining specimens were used as positive and negative controls and all specimens underwent thermocycling (1000; 5-55°C). The sealing ability of all samples was evaluated using the leakage model for glucose. The samples were analyzed by a spectrophotometer in quantitative glucose microleakage test over a period of 6 weeks. As a statistical inference, a mixed effect analysis was applied to analyze serial measurements over time.

RESULTS

The Caviton groups showed less glucose penetration in comparison with the IRM groups. The Caviton 4 mm group demonstrated relatively low glucose leakage over the test period. High glucose leakage was detected throughout the test period in all IRM groups. The glucose leakage level increased after 1 week in the Caviton 2 mm group and after 4 weeks in the Caviton 3 mm and 4 mm groups (p < 0.05).

CONCLUSIONS

Caviton had better sealing ability than IRM in the glucose penetration model during 6 weeks. Temporary filling of Caviton to at least 3 mm in thickness is necessary and temporary filling periods should not exceed 4 weeks.

Fluid flow evaluation of coronal microleakage intraorifice barrier materials in endodontically treated teeth

Objective:

The objective of this study was to compare the coronal microleakage intraorifice barrier materials, called CoroSeal (CS), fissur sealant (FS), flowable composite FC, and policarboksilate cement (PC), by using the computerized fluid filtration method.

Materials and Methods:

Fifty freshly extracted, single-canal human maxillary central teeth were used in this study. The teeth were decoronated to a standardized root length of 15 mm. After preparation and irrigation, all the teeth were obturated with gutta-percha and AH-Plus. In all teeth, the coronal 2 mm of root filling was removed and replaced with one of the intraorifice barriers. According to intraorifice barriers, teeth were divided randomly into 4 experimental groups (n = 10) and 2 control groups (n = 5). Group 1: CS; Group 2: FS; Group 3: FC; and Group 4: PC.

Positive Control Group:

No barrier material was used.

Negative Control Group:

Roots were completely coated with the nail polish, including the orifice. Leakage was evaluated by using a computerized fluid filtration model. Differences in fluid filtration among groups were subjected to statistical analysis using the Kruskal-Wallis Test and multiple comparisons test.

Results:

A value of P < 0.05 was statistically significant. Statistical analysis has indicated that the CS leaked significantly less than other groups (P < 0.05). There was a significant difference between FS and PC (P < 0.05), in contrast there was no significant difference between FS and FC (P > 0.05).

Conclusions:

Using the CS material as an intraorrifice barrier material reduced amount of microleakage as compared with FS, FC, and PC.

Evaluation of efficacy of chlorhexidine intracanal medicament on the periodontal healing of concomitant endodontic-periodontal lesions without communication: an interventional study

BACKGROUND

Treatment of concomitant endodontic-periodontal lesions remains a challenge in clinical practice and requires effective endodontic and regenerative periodontal therapy. Among other factors, cross seeding and recolonization of flora may affect the outcome of periodontal therapy. Intracanal medicaments have been shown to exert antimicrobial activity on the external root surface, and local delivery of antimicrobials has been suggested to be a complementary approach in the management of periodontitis. Therefore, the objective of this study is to determine the influence of chlorhexidine (CHX) intracanal medicament on the clinical outcomes of therapy.

METHODS

Thirty-one patients were divided into two treatment groups: 1) open flap debridement (OFD) in endodontically treated teeth (control); and 2) OFD in endodontically treated teeth with CHX placed in the coronal space (test). The clinical variables evaluated were probing depth (PD), clinical attachment level (CAL), and percentage of sites with PD ≥5 mm. Reevaluation was performed at 3 and 6 months post-surgery.

RESULTS

Both treatments resulted in improvement in all the clinical variables evaluated. Postoperative measurements from test and control groups showed reductions in mean PD of 2.22 ± 1.27 and 0.91 ± 0.81 mm, mean CAL gains of 2.16 ± 1.12 and 0.60 ± 0.93 mm, and 43.33% ± 31.37% and 17.71% ± 14.23% reduction in sites with PD ≥5 mm. Significantly more PD reduction, CAL gain, and percentage reduction in sites with PD ≥5 mm were observed in the test group at 6 months (P <0.05).

CONCLUSION

CHX may be used as an effective intracanal medicament for promoting periodontal healing in concomitant endodontic-periodontal lesions.

Ability of new obturation materials to improve the seal of the root canal system: a review

New obturation biomaterials have been introduced over the past decade to improve the seal of the root canal system. However, it is not clear whether they have really produced a three-dimensional impervious seal that is important for reducing diseases associated with root canal treatment. A review of the literature was performed to identify models that have been employed for evaluating the seal of the root canal system. In vitro and in vivo models are not totally adept at quantifying the seal of root canals obturated with classic materials. Thus, one has to resort to clinical outcomes to examine whether there are real benefits associated with the use of recently introduced materials for obturating root canals. However, there is no simple answer because endodontic treatment outcomes are influenced by a host of other predictors that are more likely to take precedence over the influence of obturation materials. From the perspective of clinical performance, classic root filling materials have stood the test of time. Because many of the recently introduced materials are so new, there is not enough evidence yet to support their ability to improve clinical performance. This emphasizes the need to translate anecdotal information into clinically relevant research data on new biomaterials.

Bond strength to root dentin and fluid filtration test of AH Plus/gutta-percha, EndoREZ and RealSeal systems

OBJECTIVES

To investigate the bond strength and seal ability produced by AH Plus/gutta-percha, EndoREZ and RealSeal systems to root canal dentin.

MATERIAL AND METHODS

Sixty extracted single-root human teeth, instrumented manually to size 40, were divided into three groups (n=20) according to the sealer used; G1: AH Plus, G2: EndoREZ, and G3: RealSeal sealers. After filling using the lateral condensation technique, each sealer group was randomly divided into two subgroups according to the tests applied (n=10 for µPush-out test and n=10 for fluid filtration test). A fluid filtration method was used for quantitative evaluation of apical leakage. Four 1-mm-thick slices (cervical and medium level) were obtained from each root sample and a µPush-out test was performed. Failure modes were examined under microscopy at 40x, and a one-way ANOVA was applied to analyze the permeability. Non-parametrical statistics for related (Friedman's and Wilcoxon's rank tests) or unrelated samples (Kruskal-Wallis' and Mann-Whitney's tests) allowed for comparisons of µPush-out strength values among materials at the different levels. Statistical significance was accepted for p values <.05.

RESULTS

There are no significant differences among fluid filtration of the three sealers. The sealer/core material does not significantly influence the µPush-out bond strength values (F=2.49; p=0.10), although statistically significant differences were detected with regard to root level (Chi2=23.93; p<0.001). AH Plus and RealSeal obtained higher bond strength to intraradicular dentin in the medium root slices.

CONCLUSIONS

There are no significant differences between the permeability and global µPush-out bond strength to root canal dentin achieved by AH Plus/gutta-percha, EndoREZ and RealSeal systems.

Influence of the Method in Root Canal Filling Using Active Lateral Compaction Techniques

The aim of this study was to evaluate, by stereomicroscopy and confocal laser microscopy, the influence of different lateral compaction methods for the obturation quality, as well as the time spent for the procedure. Thirty root canals of freshly extracted single-rooted human teeth were prepared with the ProTaper system up to F5 instrument and filled with gutta-percha and AH Plus sealer by the lateral compaction technique. The teeth were divided into 3 groups (n=10) in accordance with the method used for the lateral compaction, as follows: Manual, Mechanical and Ultrasonic. The sealers were stained with rhodamine B dye in a proportion of 0.1% per gram in weight to allow for the analysis under a confocal microscope. During the root filling procedure, the time spent was recorded with a stopwatch. The specimens were stored at 37 °C for 48 h, and then sectioned at 2, 4 and 6 mm from the apex. The percentage of gutta-percha, sealer and void areas were evaluated using a stereomicroscope and sealer penetration perimeter by confocal laser microscope. Statistical analyses were performed using the Kruskall-Wallis and Dunn tests (p<0.05). The mechanical method required a shorter time for the lateral compaction than the manual method (p<0.05). There were no significant differences (p>0.05) for the perimeter of the dentin with sealer penetration among all groups. The mechanical method showed a higher (p<0.05) percentage of gutta-percha and less sealer at the 4 mm section in comparison with the manual method. The ultrasonic group showed intermediate values. The void areas found in the root filling were similar (p>0.05) between the three methods. In conclusion, the fastest lateral compaction was achieved with the mechanical method, and all the methods showed void areas in the root filling.

Evaluation of the apical sealing ability and adaptation to the dentin of two resin-based Sealers: An in vitro study

AIM

To quantitatively evaluate the apical sealing ability and adaptation of two resin-based sealers to dentin.

MATERIALS AND METHODS

Fifty freshly extracted mandibular first premolars were taken and sectioned at the cemento-enamel junction. Thirty teeth were subjected to a leakage study by the resin infiltration method with two groups of 10 teeth each. Group I teeth were obturated with methacrylate resin-based sealer (EnoRez) and Group II teeth were obturated with epoxy resin-based sealer (AH Plus). The remaining 10 teeth were used as controls (positive and negative of five teeth each). Twenty teeth were divided into two groups and obturated as in the leakage study and subjected to a scanning electronic microscopy (SEM) analysis for adaptation and resin depth penetration.

RESULTS

Both the sealers produced apical leakage to a certain extent. The adaptation and resin sealer penetration in the coronal and middle thirds was better than in the apical third of the root canal under SEM observation. The hybridized resin sealer tags in the coronal and middle thirds of Group I were much longer than that shown by Group II.

CONCLUSION

We conclude that the physical integrity of the sealer matrix may also be important in providing resistance to leakage.

Lack of correlation between obturation limits and apical leakage

The aim of this paper was to evaluate a possible correlation between obturation limits and leakage. Thirty-six extracted human mandibular incisors were used, characterized by straight and single canals, non-anatomical complexities, absence of previous endodontic treatment, complete root formation and patent foramen. For standardization of the specimens for the leakage analysis, foraminal instrumentation was performed up to a Flexofile #25 (Dentsply-Maillefer, Ballaigues, Switzerland). All specimens were instrumented and filled following the same protocol, and the obturation limits were measured using Axiovision 4.5 Software (Carl Zeiss Vision, Hallbergmoos, Germany). The specimens were then separated into three groups (n=12) according to the following variables: Group I--obturation limits ranging from 0 mm to 0.76 mm of the main apical foramen. Group II--obturation limits ranging from 0.77 mm to 0.98 mm of the main apical foramen. Group III--obturation limits ranging from 0.99 mm to 1.68 mm of the main apical foramen. Apical leakage was quantified by fluid filtration. The analyses were confronted using Pearson's test (p>0.05). Groups I, II and III showed Pearson correlation values (r2) of -0.152, -0.186 and 0.058, respectively. No correlation was found between the obturation limits and apical leakage.

3D analyses of interface voids in root canals filled with different sealer materials in combination with warm gutta-percha technique

OBJECTIVES

The aim of the present study was to analyze the formation of voids and gaps in root canals obturated with different sealer materials in combination with warm gutta-percha vertical compaction technique by using BeeFill® 2in1.

MATERIALS AND METHODS

Twenty-four single-rooted teeth were collected, and root canals were prepared by using rotary files. All teeth were randomly allocated into three groups. Each group was obturated by using the BeeFill® 2in1 system in combination with Sealapex (non-eugenol, calcium hydroxide polymeric root canal sealer; Kerr Sybron, USA), RoekoSeal (polydimethylsiloxane-based sealer; Roeko, Germany), or 2Seal (epoxy-amine resin-based sealer; VDW, Germany). Following preparation, all teeth were scanned with a micro-computed tomography (CT) scanner, and a three-dimensional reconstruction of the obturated root canals was performed to analyze the volume of interface voids and gaps in the obturated teeth.

RESULTS

Statistical analysis demonstrated that the silicon-based sealer RoekoSeal induced significantly less voids and gaps than other tested materials. The amount of voids and gaps significantly was higher in the apical region.

CONCLUSIONS

These data indicate that none of the root canal-filled teeth were free of gaps. Teeth obturated with RoekoSeal demonstrated to have the highest quality in terms of voids and gaps formation in combination with the BeeFill® 2in1 obturation system.

CLINICAL RELEVANCE

These findings point to the potential benefit of micro-CT analyses for in vitro evaluation of root canal obturation systems and provide further information about sealer materials used in combination with a warm gutta-percha vertical compaction technique.

Root canal hydrophobization by dentinal silanization: improvement of silicon-based endodontic treatment tightness

A new strategy to improve silicon-based endodontic treatment tightness by dentine hydrophobization is presented in this work: root dentine was silanized to obtain a hydrophobic dentine-sealer interface that limits fluid penetration. This strategy was based on the grafting of aliphatic carbon chains on the dentine through a silanization with the silane end groups [octadecyltrichlorosilane (OTS) and octadecyltriethoxysilane]. Dentine surface was previously pretreated, applying ethylenediaminetetraacetic acid and sodium hypochlorite, to expose hydroxyl groups of collagen for the silane grafting. Collagen fibers exposure after pretreatment was visible with scanning electron microscopy, and Fourier transform infrared (FTIR) spectroscopy showed their correct exposition for the silanization (amide I and II, with 1630, 1580, and 1538 cm⁻¹ peaks corresponding to the vibration of C=O and C--N bonds). The grafting of aliphatic carbon chains was confirmed by FTIR (peaks at 2952 and 2923 cm⁻¹ corresponding to the stretching of C--H bonds) and by the increasing of the water contact angle. The most efficient hydrophobization was obtained with OTS in ethyl acetate, with a water contact angle turning from 51° to 109°. Gas and liquid permeability tests showed an increased seal tightness after silanization: the mean gas and water flows dropped from 2.02 × 10⁻⁸ to 1.62 × 10⁻⁸ mol s⁻¹ and from 10.8 × 10⁻³ to 5.4 × 10⁻³ µL min⁻¹, respectively. These results show clear evidences to turn hydrophilic dentine surface into a hydrophobic surface that may improve endodontic sealing.

In vitro comparative study of sealing ability of Diadent BioAggregate and other root-end filling materials

AIM

This in vitro study evaluated and compared sealing ability of Diadent BioAggregate (DBA) as a new root-end filling material (REFM) versus amalgam, intermediate restorative material (IRM) and white mineral trioxide aggregate (WMTA).

MATERIALS AND METHODS

Crowns of sixty extracted human maxillary incisors were sectioned at the cemento-enamel junction (CEJ). All the roots were instrumented and obturated with gutta-percha and resin sealer. Obturated roots were divided randomly into 2 control groups and 4 experimental groups of 10 samples each. In the negative control group (group I), roots were kept without any further preparation. In the positive and experimental groups roots, were apically resected and root-end cavities were prepared and filled with: (a) gutta-percha (group 2-positive control group); (b) amalgam (group 3); (c) IRM (group 4); (d) WMTA (group 5); (e) DBA (group 6). Apical leakage was assessed using dye penetration technique. Data were submitted to statistical analysis by the one-way analysis of variance (ANOVA) and Tukey's test.

RESULTS

Significant difference of sealing ability was found among 4 tested groups. DBA followed by MTA showed the highest sealing ability.

CONCLUSIONS

DBA with its high sealing ability can be considered a possible alternative to MTA.

Is endodontic re-treatment mandatory for every relatively old temporary restoration? A narrative review

OBJECTIVES AND BACKGROUND

In this review, the authors examine whether there is any decisive evidence to support the revision of root fillings that have been exposed to the oral environment for more than three months, undertaken solely because of suspicions of microleakage. Researchers in numerous endodontic studies have addressed the evaluation of coronal microleakage by using different tracers and techniques. The need to achieve a tight, permanent coronal seal as soon as possible after the completion of endodontic treatment is obvious. However, the clinical importance of microleakage studies recently has been questioned because of their wide range and even contradictory results, and findings from only a few clinical investigations have demonstrated a clear relationship between the endodontic success rate and failure rate owed to coronal microleakage in cases involving high-quality endodontic therapy.

METHODS

The authors analyzed commonly cited articles regarding the clinical relevance of microleakage studies and the success rate of teeth with compromised restorations.

CONCLUSIONS

In a review of the literature, the authors found no clear evidence to support immediate replacement of well-obturated endodontic treatment that has lasted more than three months solely because of suspicions of microleakage. It may be prudent in such cases to make a new coronal restoration immediately and to observe the tooth for at least three months before placing the permanent crown.

Seal capability of interim post and core crown with temporary cements

The purpose of the present study was to evaluate the in vitro seal capability of interim post and core crown restorations. Eighty teeth were selected and divided into 8 groups. Four experimental groups received interim posts and core crowns. Half of each group was decoronated at the cementum-enamel junction, groups PCCH and PCZO. The other half was sectioned 2 mm coronal to the cementum-enamel junction, groups PCrZO and PCrCH. The interim post and core crowns were luted with Rely X Temp NE, groups PCrZO and PCZO; Hydro C was used for Groups PCrCH and PCCH. The control groups, PC and PCr, received uncoated post and core crowns; groups OTg and OT were left without interim post and core crowns and were totally open. Infiltration was accessed by dye exposure followed by demineralization of the teeth. The length of the infiltration was measured using digital images taken from the specimens. The images were inserted into the Image Tool 3.0 software. Kruskal-Wallis analysis of variance and Dunn's multiple comparison method were used to test for significant differences among test groups (P < .05). Groups PCrZO and PCrCH showed the least dye penetration, followed by groups PCZO and PCCH. Teeth restored with interim post and core crowns will be subject to leakage. Ethics Committee: 095/2008.

Resin materials for root canal obturation

With the appearance of more in vivo and ex vivo publications, methacrylate based resin sealers are becoming more popular in endodontics. Their ease of use and favorable clinical performance offer an attractive alternative to conventional endodontics. This article reviews the development of resin-based sealers and biocompatibility tests. The many, mostly opposing views are analyzed to put what has been published thus far in perspective. A critical analysis of the facts leads to the consensus that methacrylate based resin sealers are here to stay and offer a suitable alternative to conventional endodontic treatment.

Volumetric analysis of root fillings using spiral computed tomography: an in vitro study

AIM

To analyse volumetrically using spiral computed tomography (SCT) the efficacy of various techniques to fill root canals.

METHODOLOGY

Root canals in 40 maxillary central incisors were instrumented with K-files to size 60 and the volume of the canal measured using SCT. The teeth were divided into four groups of 10 each and root filled by lateral compaction, Thermafil, Obtura II and System B techniques, respectively. AH plus was used as sealer with all techniques. The filled volume in each canal was measured using SCT and the percentage of obturated volume (POV) was calculated. The data were statistically analysed using Kruskal-Wallis test and Mann-Whitney U-test.

RESULTS

The four groups were comparable in canal volume. The overall POV was 80.4%, 93.3%, 84.8% and 93.7% for lateral compaction, Thermafil, Obtura II and System B, respectively (P < 0.05).

CONCLUSION

The greatest POV was obtained with System B and Thermafil. Voids were seen in all root fillings.

Strategies for the endodontic management of concurrent endodontic and periodontal diseases

Endodontic and periodontal diseases can provide many diagnostic and management challenges to clinicians, particularly when they occur concurrently. As with all diseases, a thorough history combined with comprehensive clinical and radiographic examinations are all required so an accurate diagnosis can be made. This is essential since the diagnosis will determine the type and sequence of treatment required. This paper reviews the relevant literature and proposes a new classification for concurrent endodontic and periodontal diseases. This classification is a simple one that will help clinicians to formulate management plans for when these diseases occur concurrently. The key aspects are to determine whether both types of diseases are present, rather than just having manifestations of one disease in the alternate tissue. Once it is established that both diseases are present and that they are as a result of infections of each tissue, then the clinician must determine whether the two diseases communicate via the periodontal pocket so that appropriate management can be provided using the guidelines outlined. In general, if the root canal system is infected, endodontic treatment should be commenced prior to any periodontal therapy in order to remove the intracanal infection before any cementum is removed. This avoids several complications and provides a more favourable environment for periodontal repair. The endodontic treatment can be completed before periodontal treatment is provided when there is no communication between the disease processes. However, when there is communication between the two disease processes, then the root canals should be medicated until the periodontal treatment has been completed and the overall prognosis of the tooth has been reassessed as being favourable. The use of non-toxic intracanal therapeutic medicaments is essential to destroy bacteria and to help encourage tissue repair.

The quality of single cone and laterally compacted gutta-percha fillings in small and curved root canals as evidenced by bidirectional radiographs and fluid transport measurements

OBJECTIVE

The aim of this study was to examine the quality of root fillings in small and curved root canals using bidirectional radiographs and fluid transport (FT) measurements.

STUDY DESIGN

Root canals in eighty 38 degrees -curved mesial roots of mandibular molars were prepared using a balanced force technique. Samples were divided into 4 groups of 20 each and obturated by either the cold lateral compaction (LC) or the single cone (SC) technique, using either epoxy resin-based or zinc oxide-eugenol sealers. Bidirectional (buccolingual and mesiodistal) radiographs were acquired from each root. The voids along the root filling were assessed. The FT along the root filling was measured using an FT monitoring device. The differences between the groups regarding FT and the bidirectional radiographic score were analyzed by means of a Kruskal-Wallis test. The correlation between the FT values and the radiographic scores were analyzed using a Spearman test.

RESULTS

Three groups of LC or SC fillings containing epoxy resin-based sealers exhibited similar radiographic scores and FT values (P > .05). The group of SC fillings that contained zinc oxide-eugenol sealer had worse radiographic scores than the other groups (P = .047). The bidirectional radiographic scores and the FT values for the 80 filled roots were strongly correlated (r(2) = 0.519; P = .00001).

CONCLUSION

Root fillings of similar quality were confirmed in small and curved root canals filled using either a single cone or laterally compacted gutta-percha and epoxy resin-based sealers.

Bacterial and dye penetration through interim restorations used during endodontic treatment of molar teeth

INTRODUCTION

The purpose of this study was to investigate the association between dye and bacterial penetration through interim restorations used during endodontic treatment.

METHODS

Sixty-four extracted human teeth were used, with 2 teeth each as positive and negative controls. Endodontic access with a mesio-occluso-distal cavity was prepared. Palatal cusps of maxillary molars and buccal cusps of mandibular molars were removed. Cotton was placed over the canals and covered with Cavit. Thirty teeth were restored with Ketac Silver (KS) and 30 with KS reinforced with a stainless steel band (KSSB). Samples were submersed in India ink mixed with brain heart infusion broth containing Streptococcus gordonii. After 3 months of simulated chewing, structural integrity and dye and bacterial penetration were assessed.

RESULTS

Positive controls had both dye and bacterial penetration. Negative controls had no dye or bacterial penetration. All KS restorations debonded, whereas 18 KSSB restorations (60%) debonded. KS restorations were 1.67 times more likely to debond than KSSB restorations (Fisher exact test). KS was 1.3 times more likely to have dye penetration than KSSB (Fisher exact test) and 3 times more likely to have bacterial penetration, although not statistically significant (chi(2) test). Overall, 88.3% of specimens had dye penetration, and 20% had bacterial penetration. This 68.3% difference indicated no association between dye and bacterial penetration (exact McNemar test).

CONCLUSIONS

Stainless steel bands helped maintain structural integrity of KS restorations under masticatory function. Bands helped prevent dye penetration but not bacterial penetration. There was no association between dye and bacterial penetration.

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.

Gas permeability: a new quantitative method to assess endodontic leakage

AIM

The aim of this study was to evaluate a new endodontic leakage measurement method.

MATERIALS AND METHODS

Permeability was assessed measuring the gas flow passing through the root. Positive and negative tests were carried out to assess the validity of the method. We used glass capillaries for calibration (diameters of 15, 30, 40, 50 and 75 microm). The applicability of the method was assessed with human teeth using three sealing methods: GuttaFlow (GF) and a single cone; Pulp Canal Sealer (PCS) and a single cone; PCS and system B.

RESULTS

This method demonstrated to be highly reproducible as the standard deviation was approximately 1% on average with glass capillaries. Significantly higher leakage (p<0.05) was recorded for endodontic treatment with GF and single cone compared to PCS and single cone and PCS with system B.

CONCLUSION

Gas permeability is quantitative, sensitive, non-destructive and reproducible and seems appropriate for endodontic tests. It would participate in the indirect comprehension of leakage phenomena.