[Impact of GuttaFlow Bioseal sealer on the vertical fracture resistance of oval-shaped canals].

PURPOSE: To investigate the effect of GuttaFlow Bioseal root canal sealer on the vertical root fracture resistance of oval-shaped root canals. METHODS: Sixty orthodontically subtracted maxillary and mandibular single-rooted premolar teeth were scanned with CBCT. Oval canals were eligible when the buccolingual diameter of the canal was greater than or equal to two times the mesiodistal diameter at a distance of 5 mm from the root apex. Thirty single-rooted premolars with oval-shaped root canals were prepared to F2 using the Protaper system and then randomly divided into the GuttaFlow Bioseal filling group and iRoot SP filling group. Each group was further divided for root canal filling using warm vertical compression, cold lateral condensation and single cone techniques. Five single-rooted premolars was chosen as a negative control group. After 30 days of storage in a constant thermotank at 37 ℃ and 100% humidity, the filled roots were vertically placed into a cylindrical model of self-polymerizing acrylic resin. Subsequently, the samples were fixed on the lower plate of a universal testing machine, and a ball of 4 mm in diameter was applied vertically with a downward pressure at a speed of 1 mm/min until fracture occurred. The load values were recorded in Newtons. The data were analyzed using SPSS 29.0 software package. Fracture patterns were examined under microscope. RESULTS: T test results showed no significant difference between the GuttaFlow Bioseal-filled and iRoot SP-filled groups (P=0.321). One-way ANOVA showed a significant difference in vertical fracture resistance between the groups(P＜0.05), and LSD analysis showed that the GuttaFlow Bioseal-filled sample teeth were significantly more resistant to vertical fracture than the iRoot SP when using the thermal vertical compression filling method and the single-tip method(P＜0.05). In contrast, the GuttaFlow BIoseal-filled group was significantly less resistant to vertical fracture than the iRoot SP group when using the cold lateral compression filling method(P＜0.05). CONCLUISIONS: GuttaFlow Bioseal has the potential to improve root resistance to vertical fracture when filling root canals using the thermal vertical pressurization method and the single-tip method, but more clinical trials are needed to validate this result and its long-term prognosis.

Quality of Root Canal Fillings and Procedural Errors for In Vivo Studies Prepared in Different Clinical Settings and with Rotary Systems: A Systematic Review.

BACKGROUND This systematic review of the literature aimed to identify published studies and evaluate them on the quality of root canal fillings (RCF) and procedural errors with rotary systems for in vivo studies prepared for different clinical settings. MATERIAL AND METHODS A full literature exploration was conducted in Clarivate Analytics' Web of Science, Elsevier's Scopus, Embase, and PubMed for studies published between January 2020 and March 2024. A manual search was also performed by reviewing the references of selected papers. The following keywords were used: quality of root canal filling(s) OR quality of root canal obturation, root canal obturation OR endodontic treatment, clinical setting (academic, private, governmental), AND/OR procedural errors and rotary instrumentation. RESULTS Sixteen clinical studies were included in this review. The acceptance percentages for obturation length, density, and taper were 76.3%, 74.7%, and 82.5%, respectively, indicating significantly high, good ratios. The overall RCF recorded showed that 68.2% of root canal obturations were considered acceptable. Acceptable rates remained higher than unacceptable rates in academic, hospital, and private settings, and percentages ranged from 65.2% to 93.0%. Only 5 studies reported procedural errors, namely, ledge formation, separated instruments, apical perforation, transportation, lateral perforation, and root/foramen perforation. CONCLUSIONS Using rotary instruments for different root canal treatment steps as instrumentation and obturations is highly recommended. Among different clinical setting and practice, these instruments resulted in a good and acceptable RCF, overall quality performed by those instruments, and few procedural errors.

Clinical outcome of non-surgical root canal treatment using different sealers and techniques of obturation in 237 patients: A retrospective study.

OBJECTIVES: The aim of this retrospective study was to compare the clinical results of two root canal sealers and three obturation techniques used for non-surgical root canal treatment. MATERIALS AND METHODS: A total of two hundred eighty-three root canal treated teeth in two hundred thirty-seven patients with minimum a 6-month follow-up was included for this study. The canals were filled with three different modes: 1) cold lateral condensation (CLC) and AH Plus Sealer; 2) continuous wave condensation technique (CWC) and AH Plus Sealer, and 3) sealer-based obturation technique (SBO) and AH Plus Bioceramic Sealer. The treatment outcome was analysed based on clinical signs and symptoms, and periapical radiograph (periapical index, PAI). RESULTS: There were no significant differences in treatment outcome between various sealers and filling techniques applied. The sealer extrusion was found most frequently in the CWC group (60.67%), followed by SBO (59.21%) and CLC (21.19%) with statistically significant differences (p < .05). The initial diagnosis, previous treatment and sealer extrusion (p < .05) were prognostic factors that affected treatment outcome. CONCLUSIONS: Based on the findings of this study, neither the sealer type nor the filling technique affected the treatment success while preoperative diagnosis, previous treatment and sealer extrusion had significant effect on the outcome. CLINICAL RELEVANCE: A bioceramic sealant applied along with the single-cone technique might be considered as an alternative method in root canal obturation.

Pre-Sealing of Endodontic Access Cavities for the Preservation of Anterior Teeth Fracture Resistance.

OBJECTIVE: Sodium hypochlorite solution (NaOCl) is an effective canal irrigant but interferes with the mechanical features of dentin and the bonding capability of adhesives when restoring endodontically treated teeth. This study evaluated whether access cavity resin sealing before using canal irrigant would augment the resistance of endodontically treated anterior teeth against fracture. METHODS: Sixty maxillary incisors underwent endodontic treatment in five groups (n = 12). Irrigation with 5.25% NaOCl and 17% ethylenediaminetetraacetic acid (EDTA) was performed in all groups except for Group 5. After root canal obturation, in Group 1, the access cavity was kept unrestored. In Group 2, immediate restoration after obturation was achieved. For Group 3, delayed restoration after 1 week was provided. In Group 4 (pre-sealed), before canal irrigation, the dentin surface of access cavities was sealed using self-adhesive composite resin (Vertise Flow) and then restored after obturation. In Group 5, which was saline irrigated, immediate restoration was performed. After storage and thermal cycling for 5000 cycles at 5°C-55°C with a dwell time of 15 s and a transfer time of 5 s, teeth were statically loaded by a universal testing machine until a fracture occurred. Data were collected as the fracture resistance (FR) and analyzed using the one-way analysis of variance and Tukey's tests. RESULTS: FR significantly differed between all groups (p < 0.001). The lowest FR was recorded in the unrestored group (284 ± 86 N), which was not statistically different from the immediately restored group (p = 0.065). The pre-sealed group exhibited the highest FR value (810 ± 127 N, p ≤ 0.02 vs. other groups). The FR of the saline-irrigated and delayed restored groups was almost similar (p = 0.13). CONCLUSIONS: NaOCl/EDTA irrigation resulted in an adverse effect on FR. Delayed restoration could reduce this adverse effect. Access cavity pre-sealing with flowable composites led to a higher FR than conventional methods and may be considered an effective step during treatment procedures.

Quality of different obturation techniques to fill perforating internal root resorption: a micro-computed tomographic study.

BACKGROUND: This study aimed to assess the quality of various obturation techniques to fill perforation caused by internal root resorption using Micro-computed Tomography. METHODS: Cone-beam computed tomography images of a maxillary central incisor tooth with perforating internal resorptive defect were used to create a 3D printed model of the affected tooth. The replicas were divided into four groups based on the obturation technique used. The techniques included Group 1: a polydimethylsiloxane-based sealer (GuttaFlow-2) with gutta-percha. Group 2: same as Group 1 except for using a pre-mixed Bioceramic-based sealer (NeoSEALER Flo). Group 3: the defect was filled entirely using the NeoSealer Flo Bioceramic-based sealer. Group 4: the samples were obturated using the warm vertical compaction technique with a resin-based sealer (ADSeal). The resin models were then scanned a micro-computed scanner to evaluate the percentage of voids in each group. RESULTS: The results showed that NeoSEALER Flo groups had significantly the highest volume of voids while GuttaFlow-2 and warm vertical compaction groups had the lowest void volume. CONCLUSIONS: GuttaFlow-2 and warm vertical compaction techniques performed best in filling the internal resorptive defect.

Evaluation of Microleakage of Nanoparticle-incorporated Cyanoacrylate Root Canal Sealer Using the Radioisotopic Method: An In Vitro Study.

AIM OF THE STUDY: The study aimed to assess the microleakage of nanoparticle-based (NPB) cyanoacrylate sealer and epoxy resin-based (ERB) sealer using radioisotope method and confocal laser scanning microscopy (CLSM). MATERIALS AND METHODS: A total of 100 single-rooted teeth were collected; specimens were accessed, instrumented, and irrigated, and randomly distributed into 4 groups of 25 samples each: Group I: Positive control, group II: Negative control, group III: Obturated with NPB sealer, and group IV: Obturated with ERB sealer. All samples were immersed in 99mTc pertechnetate solution, for 3 hours after which radioactivity was estimated under a Gamma camera. The radioactivity released by specimens before and after nail varnish removal was statistically analyzed. After 2 weeks, the same samples were used for CLSM analysis. The sealer tubular penetration depth was measured at the deepest level for each group using ZEN lite 2012. Data collected was statistically evaluated. RESULTS: The amount of radioactivity observed at first in group III and group IV was 194.76 and 599.12 units, respectively, with p-value < 0.001, indicating significant interaction, and after nail varnish removal, it was 89.68 and 468.44 units, respectively, with a p-value < 0.001; again, indicating statistical significance. Hence, the radioactivity of NPB sealer was found to be lower than ERB sealer in both cases, indicating better sealing of the former. The photomicrographs show that mean value of dye penetration in NPB sealer in first, second, and third segment from apex was 85.06, 75.73, and 66.09, respectively; while in the case of ERB sealer, those were 597.28, 461.17, and 195.68, respectively; with p-value < 0.001; signifying that NPB sealer exhibited higher resistance to microleakage than ERB sealer. CONCLUSION: The NPB sealer can become a potential root canal sealer in future endodontics due to superior physiochemical properties attributed to the cyanoacrylate and incorporated nanoparticles. CLINICAL SIGNIFICANCE: The study clinically signifies that we can equally use the radioisotopic method along with confocal method while conducting the microleakage studies. In addition, NPB sealer can be an emerging replacement with better properties than gold standard root canal sealers for clinical use. How to cite this article: Shetty C, Qaiser S, Shetty A, et al. Evaluation of Microleakage of Nanoparticle-incorporated Cyanoacrylate Root Canal Sealer Using the Radioisotopic Method: An In Vitro Study. J Contemp Dent Pract 2024;25(4):335-341.

Filling ability of ready-to-use or powder-liquid calcium silicate-based sealers after ultrasonic agitation.

This study evaluated the effect of ultrasonic agitation on the filling capacity of ready-to-use calcium silicate-based sealer Bio-C Sealer (BCS, Angelus, Paraná, Brazil) or powder-liquid BioRoot RCS (BR, Septodont, Saint-Maur-des-Fossés, France) using curved artificial canals by micro-computed tomography (micro-CT). Additionally, flow (mm) and flow area (mm2) were evaluated for both materials. Acrylic resin main canal (60° curvature and 5 mm radius, with 3 lateral canals in the cervical, middle, and apical thirds) were prepared up to size 40/.05 (Prodesign Logic, Brazil). The agitation method was used with ultrasonic tip (US, Irrisonic, Helse, Brazil): BCS, BCS/US, BR, and BR/US. All specimens were filled using the single-cone technique. The samples were scanned by micro-CT (8,74 µm) after obturation. The percentage of filling material and voids were calculated. Flow was evaluated based on ISO 6876/2012 standards (mm) and area (mm2). The data were statistically analyzed using ANOVA and Tukey tests (α = 0.05). BR/US showed lower percentage of filling material in the lateral canals than and, BCS/US (p<0.05). BR/US resulted in a higher percentage of voids than BR in the lateral apical third (p<0.05). BCS showed higher flow than BR (p<0.05). BCS and BR presented proper filling capacity in the simulated curved canals regardless of the use of ultrasonic agitation. However, BR/US showed more voids in the apical third. BCS demonstrates higher filling ability.

Effect of the filling technique on the filling removal from oval-shaped canals.

OBJECTIVES: This ex vivo study aimed to evaluate the influence of different filling techniques on the filling removal from oval root canals filled with bioceramic sealer. METHODS: Thirty-six mandibular incisors with single oval canals were filled with bioceramic sealer following the techniques (n = 12): single-cone, modified McSpadden, or continuous wave of condensation, and scanned by micro-computed tomography (micro-CT). The filling was removed using the Clearsonic ultrasound tip and Reciproc system up to the R40 instrument, and the working time was recorded. The teeth were scanned again by micro-CT. Percentage of remnant volume (mm³) of the filling material, dentin thickness, and root canal transportation were measured. The data was analyzed using parametric and non-parametric tests with a significance level of 5%. RESULTS: It took more time to remove the filling material using the continuous wave of condensation technique (p < 0.05), followed by the modified McSpadden and single-cone techniques. There was no difference (p > 0.05) when comparing the percentage of remaining filling material among the three groups, nor did it among the segments of each tooth. There was also no difference in the analysis of dentin thickness and transportation when comparing the groups (p > 0.05). CONCLUSIONS: The filling technique did not influence the amount of remaining filling material, dentin thickness, and transportation. The working time was longer with thermoplastic filling techniques. CLINICAL RELEVANCE: Endodontic retreatment in teeth filled with bioceramic sealers increases with their use. Several techniques are used to fill the root canals, thus, it is important to know whether the filling technique influences the non-surgical endodontic retreatment.

Effect of continuous vs sequential chelation on the mechanical properties of root dentin: An ex vivo study.

OBJECTIVES: To evaluate the mechanical properties of root canal dentin treated with sodium hypochlorite (NaOCl) in combination with hydroxyethylidene diphosphonic acid (HEDP) or ethylenediaminetetraacetic acid (EDTA). METHODS: For testing fracture resistance, 45 single-rooted teeth were instrumented and irrigated with NaOCl/HEDP, NaOCl/EDTA, or distilled water. Fifteen untreated teeth served as control. After obturation, specimens from the experimental groups were thermocycled, dynamically-loaded, and then statically-loaded in a universal testing machine until failure. For flexural strength analysis, 15 teeth were instrumented and irrigated with NaOCl/HEDP or NaOCl/EDTA. Root segments were sectioned into dentin bars and tested for flexural strength using a universal testing machine. For microhardness evaluation, 20 teeth were instrumented and irrigated with NaOCl/HEDP or NaOCl/EDTA. Dentin disks from the coronal-third of each root segment were prepared, one before and one after irrigation, for microhardness testing with a Knoop hardness tester. RESULTS: The highest fracture resistance was recorded in the untreated group, and the lowest in the EDTA group. Although the HEDP group had higher fracture resistance than the EDTA group, the distilled water group demonstrated even greater fracture resistance than the HEDP group. Specimens treated with HEDP had significantly higher flexural strength and microhardness values when compared with those treated with EDTA. CONCLUSION: The fracture resistance, flexural strength, and microhardness of root canal dentin were higher when root canals were irrigated with NaOCl/HEDP, when compared with NaOCl/EDTA. CLINICAL SIGNIFICANCE: Irrigating root canals with NaOCl combined with HEDP significantly improves the mechanical integrity of root canal dentin compared to the use of NaOCl with EDTA.

Influence of sealer and supplementary approach on filling material removal during endodontic retreatment.

Both root canal sealer-based and supplementary protocols may influence removal of filling material during endodontic retreatment. Mesial root canals of extracted mandibular molars were prepared using HyFlex EDM 25/.08, and filled with a calcium silicate sealer (Bio-C Sealer), or an epoxy resin (AH Plus), using the single cone technique (n = 12). Retreatment was performed using ProDesign Logic (PDL) RT and PDL 35/.05. The specimens were randomly divided into two experimental groups (n = 12), and the sealers were distributed similarly. A supplementary protocol was performed with PDL 50/.01 or XP-endo Finisher. Root canal transportation and volume, in addition to the remaining filling material percentage were evaluated using high-resolution (5 µm voxel size) micro-CT. Statistical analysis was performed using t-tests (α = 0.05). Root canals filled with AH Plus presented high residual filling material (p < 0.05). Both protocols decreased residual volume of filling material in the apical third (p < 0.05). PDL 50/.01 increased the apical root canal volume (p < 0.05). No difference was observed between the systems regarding canal transportation (p > 0.05). In conclusion, AH Plus is more difficult to remove from the apical third than Bio-C Sealer. PDL 50/.01 and XP-endo Finisher enabled greater removal of filling materials in the apical third, in the retreatment of curved root canals, without promoting apical transport.

Micro-CT determination of the porosity of two tricalcium silicate sealers applied using three obturation techniques.

PURPOSE: Using X-ray micro-computed tomography (micro-CT), the aim of this study was to measure the porosity of two tricalcium silicate sealers (EndoSequence BC and NeoSealer Flo) applied using three obturation techniques (single-cone, warm-vertical, and cold-lateral) to six single-rooted human teeth. METHODS: Six extracted, single-rooted human teeth were shaped with ProTaper Next rotary files and obturated with EndoSequence BC or NeoSealer Flo sealers and gutta-percha (GP) using one of the three techniques above. Micro-CT was used to map the full length of the canals. Deep learning cross-sectional segmentation was used to analyze image slices of the apical (0-2 mm) and coronal (14-16 mm from the apex) regions (n = 230-261 per tooth) for the areas of GP and sealer, as well as porosity. Median (%) with interquartile range of porosity were calculated , and the results were statistically analyzed with the Kruskal-Wallis test. RESULTS: In the apical region, EndoSequence BC had significantly fewer pores than NeoSealer Flo with the single-cone obturation (% median-interquartile range, IQR: 0.00-1.62) and warm-vertical condensation (5.57-10.32) techniques, whereas in the coronal region, NeoSealer Flo had significantly fewer pores than EndoSequence BC with these two techniques (0.39-5.02) and (0.10-0.19), respectively. There was no significant difference in porosity between the two sealers for the cold-lateral condensation technique in both the apical and coronal regions. CONCLUSION: For optimal obturation, the choice of technique and sealer is critical.

Clinical and radiographic success rate of the root canal filling materials used in primary teeth: A systematic review.

One of the most important factors that determine the success of pulpectomy in primary teeth is the root canal filling material used. This systematic review is an update on the success rates of various materials used for obturation in primary teeth. An electronic search was carried out in the PubMed, Scopus, Web of Science, and Cochrane Library databases with the preset inclusion and exclusion criteria. Only randomized or quasi-randomized clinical and controlled trials with a minimum follow-up of 12 months were included for analysis. Nine articles were considered potentially eligible for inclusion in this review. All the included trials had zinc oxide-eugenol (ZOE) cement as a control group. The time span of the included trials extended from 12 to 30 months. Only 2 trials were at low risk of bias. Evidence to support the success rates of obturating materials used in primary teeth is scarce, which necessitates further highquality randomized controlled clinical trials with regard to this issue.

The effect of cone beam computerized tomography voxel size and the presence of root filling on the assessment of middle mesial canals in mandibular molar teeth.

INTRODUCTION: The study aims to compare the detection of the middle mesial canal (MMC) in mandibular molar teeth using cone beam computed tomography (CBCT) with different voxel sizes when the mesiobuccal (MB) and mesiolingual (ML) canals have three distinct phases (unpreparation, preparation and obturation and the removal of the obturation and repreparation). METHODS: Two hundred forty-two extracted human mandibular molars were collected and kept in a physiological saline solution prior to use. 0.2-, 0.28- and 0.35-mm voxel sizes CBCT (n = 242) were performed in three phases (Ph): Ph1, no MB and ML canal preparation or obturation; Ph2, after MB and ML canals preparation and obturation; and Ph3, after the removal of the obturation of MB and ML canals and canals repreparation. Images were analyzed using OnDemand3D® software. After the CBCT acquisition in Ph3, all the samples were clarified to visualize the presence of the MMC directly. A blinded, previously calibrated examiner analyzed all the images. RESULTS: The MMC was detected in 15 of the 242 teeth after the clearing technique. The lowest MMC detection rate was observed at 0.35-mm voxel size regardless of the ML and MB canal condition, while the highest was observed at 0.2-mm voxel size (P < 0.05). There is no statistically significant difference between 0.2-mm and 0.28-mm voxel sizes (P > 0.05). In all voxel sizes, the highest rate of detectability of the MMC was seen in Phase 1, while the lowest was in Phase 2. CONCLUSIONS: It may be appropriate to take a 0.20-mm voxel size CBCT image, especially after the removal of root canal filling. CLINICAL RELEVANCE: An appropriate CBCT voxel size and the absence of root canal filling in the root canal system help to detect the missing MMC.

Micro-CT evaluation of the presence of voids in endodontic obturation.

Identifying the presence, size, type and location of voids in an endodontic obturation is of great clinical importance because it enables evaluation of the three-dimensionality of the sealing techniques, which can be related to the success of the endodontic treatment. AIM: To analyze by micro-CT the presence of voids in lower single-rooted premolar root canal obturations prepared using the single cone and ultrasound vibration technique. MATERIALS AND METHODS: Twenty extracted single-rooted lower premolars were selected, and the root canal prepared surgically and chemically. In GROUP 1 - Without Vibration, the canal was obturated with a single cone and bioceramic, without applying vibration. In GROUP 2 - With Vibration, the gutta-percha cone inside the root canal was held with a cotton plier to which ultrasound vibration was applied for 3 periods of 3 seconds each. A micro-CT scanner was used to acquire and reconstruct images for analysis. RESULTS: No significant difference was found between obturation techniques, though there were differences between thirds, with the cervical third having a higher percentage of voids than the middle and apical thirds. CONCLUSIONS: The results suggest that the volume of closed, open and total voids does not differ between treatments with and without ultrasound vibration. In the cervical third, the highest volume of voids was related to oval geometry in the teeth evaluated.

La presencia de vacíos en la obturación endodóntica, su tamaño y el tipo y localización tiene gran importancia clínica ya que permite evaluar la tridimensionalidad de las técnicas de sellado y relacionarlas con el éxito del tratamiento endodóntico. OBJETIVO: analizar mediante microtomografía la presencia de vacíos en la obturación del conducto radicular de premolares inferiores unirradiculares, utilizando la técnica de cono único y vibración con ultrasonido. MATERIALES Y MÉTODOS: se seleccionaron 20 premolares inferiores unirradiculares a los que se les realizó la preparación quirúrgica y química del conducto radicular. Se realizó la obturación con cono único y biocerámico GRUPO 1- sin vibración. En el GRUPO 2 - con vibración se aplicó vibración por ultrasonido, se tomó del cono de gutapercha colocado en el interior del conducto con pinza de algodón que fue vibrada durante 3 períodos de 3 segundos cada uno. Las mismas fueron adquiridas y reconstruidas en un microtomógrafo para posterior análisis de las imágenes obtenidas. RESULTADOS: No se evidenciaron diferencias significativas entre ambas técnicas de obturación comparadas, pero si entre los tercios analizados, siendo el cervical el que mayor porcentaje de vacíos presenta en comparación a los cortes correspondientes al tercio medio y apical. CONCLUSIONES: Los resultados sugieren que el volumen de vacíos cerrados, abiertos y total no varía en los tratamientos donde se aplica vibración por ultrasonido. En el tercio cervical, el mayor volumen de vacíos se relaciona con la geometría oval que presentaron las piezas dentarias evaluadas en este estudio.

Effects of Access Cavity Design and Placement Techniques on Mineral Trioxide Aggregate Obturation Quality in Simulated Immature Teeth: A Micro-Computed Tomography Study.

Background and Objectives: In teeth with open apices, performing single session apexification is a challenging treatment due to the difficulty in handling mineral trioxide aggregate (MTA). Minimally invasive approaches in dentistry have also influenced the cavity designs in endodontics. Until now, different techniques have not been investigated in addition to manual condensation during the process of placing MTA in traditional (TradACs) or conservative (ConsACs) endodontic access cavities. The aim of this in vitro study was to compare and evaluate the obturation quality of MTA apical plugs placed with different techniques in TradACs or ConsACs. Materials and Methods: Sixty upper central teeth were divided into two main groups based on cavity design, and then each main group was further divided into three subgroups according to MTA placement techniques (n = 10): TradAC-manual, TradAC-manual + indirect ultrasonic activation, TradAC-manual + XP-endo Shaper (XPS), ConsAC-manual, ConsAC-manual + indirect ultrasonic activation, and ConsAC-manual + XPS. Subsequently, the porosity percentages in the MTA apical plug were analyzed using micro-computed tomography. The statistical analysis was performed using the Kruskal-Wallis H test and Mann-Whitney U test. Statistical significance was set at p < 0.05. Results: There were differences in volume of porosity percentages (%) according to cavity designs and MTA application techniques (p < 0.05). Except for the XPS group, more porosity was observed in ConsACs compared to TradACs. In TradACs, the significantly lowest open and total porosity was observed in the manual, ultrasonic, and XPS techniques, respectively. In ConsACs, the significantly lowest porosity was observed in the manual, XPS, and ultrasonic techniques, respectively (p < 0.05). Conclusions: In MTA obturation, cavity designs and application techniques had an impact on the MTA porosity. Creating an apical plug in ConsACs may result in more porosity compared to TradACs, especially when manual or indirect ultrasonic activation is preferred. Opting for the manual technique alone may be considered sufficient for controlling porosity for both TradACs and ConsACs.

Post-operative pain in non-surgical root canal treatment after sealer-based obturation versus warm vertical compaction: A randomized clinical trial.

AIM: Post-operative pain may occur after non-surgical root canal treatment (NSRCT). The root filling technique and choice of sealer may be contributing factors. This randomized controlled clinical trial compared post-operative pain and analgesics intake after NSRCT using a sealer-based obturation technique (SBO) with single-cone gutta-percha and calcium silicate sealer (CSS) versus a warm-vertical compaction (WVC) technique with gutta-percha and a resin-based sealer (RBS). METHODOLOGY: This study was designed as a parallel-two arm, double-blind, randomized superiority clinical trial registered at www. CLINICALTRIALS: gov (NCT04753138). Patients referred for NSRCT fulfilling the inclusion criteria participated in this study. Pre-operative periapical radiographs and CBCT scans were taken and numerical rating scale (NRS) pain scores were recorded. Upon completion of canal instrumentation, participants were randomly allocated to either Group SBO: SBO with CSS or Group WVC: Warm-vertical compaction with RBS. Post-operative pain and analgesics intake were recorded at 1, 3 and 7 days after endodontic treatment completion. Non-parametric Mann-Whitney U and Friedman tests and a generalized estimating equation were used to assess differences in pain scores between the groups, within each treatment group at different time points and for correlations, respectively. RESULTS: The study included 195 participants (212 teeth). One participant declined to submit the NRS form. Therefore, 194 participants (211 teeth) were included in the final analysis (99.5% response rate). No statistically significant differences in post-operative pain or analgesic intake existed between the two groups at any time point (p > .05). Age, pre-operative pain, apical diagnosis and post-operative analgesic intake were significantly related to post-operative pain (p < .05). CONCLUSIONS: Sealer-based obturation technique with CSS was associated with similar post-operative pain levels and analgesics intake as WVC with RBS. Regarding post-operative pain, SBO with CSSs may be a suitable clinical alternative.

Root canal re-treatment with gutta percha - which techniques influence success?

OBJECTIVE: A systematic review and meta-analysis of the literature was carried out assessing the success rate of root canal retreatment using gutta percha. DATA SOURCES: Four of the largest databases were used to identify existing literature with no date or language restrictions. PubMed, Cochrane, ScienceDirect, Scopus and other additional sources were searched. Grey literature was also reviewed. STUDY SELECTION: Two authors, with Master's degrees in endodontics and with extensive university teaching experience, were selected to screen the databases to identify suitable studies. In case the authors were not able to agree during the study selection process, a third investigator was consulted. Specific inclusion and exclusion criteria were outlined and adhered to in the study selection. Two randomised controlled trials, seven single arm prospective studies and one single arm ambispective study published before the 10th of December 2022 were included. These studies evaluated the success of root canal re-treatment, obturated with gutta percha with at least a 1-year follow-up. Nine of the studies were published between 1998 and 2022. Seven studies were conducted in Europe, one in North America and one in Asia. DATA EXTRACTION AND SYNTHESIS: Standard Cochrane methods to assess interval validity were used. Risk of bias in individual studies was assessed using The Newcastle-Ottawa quality assessment scale (NOS) for single-arm studies, and the Cochrane risk of bias tool (RoB2) was used for randomised controlled trials. Outcome measures were standardised as either success or failure of root canal retreatment. Success was classified into 2 different criteria: Strict criteria = absence of clinical signs and symptoms and radiographically normal periodontal ligament space; and Loose criteria = absence of clinical signs and symptoms and absence or reduction of apical radiolucency in the control radiograph. Statistical analysis was undertaken using R software and the Freeman-Turkey transformation was performed. Results were visualised using forest plots. Heterogeneity between studies was measured using the Cochrane Q test and I2 values. RESULTS: Whilst following strict criteria, the success rate of non-surgical root canal retreatment obturated with gutta percha was 71% for 1-3 years follow-up (95% CI, 0.66-0.77) and 77% for 4-5 years follow-up (95% CI, 0.67-0.86). Heterogeneity was moderate (I2 = 61.4) and low (I2 = 0.0), respectively. Factors reducing the success rate of root canal re-retreatment under the strict criteria were older patients, mandibular teeth, molar teeth, the presence of a peri-apical radiolucency, teeth with a previous radiolucency, large peri-apical radiolucency's, higher initial periapical index scores and multiple visit-retreatments. Following the loose criteria, the success rate of non-surgical root canal re-treatment obturated with gutta percha was 87% for 1-3 years follow-up (95% CI, 0.79-0.93) with significant heterogeneity across the studies (I2 = 88.5%). Factors influencing the success rate under the loose criteria were large periapical lesions >5 mm and higher initial periapical index (PAI) scores. CONCLUSIONS: Non-surgical root canal retreatment results in favourable outcomes. However, there are several factors which can result in a lower success rate: the presence and size of a periapical radiolucency, a higher initial PAI score, multiple-visit retreatments, and the size and position of the tooth.

Performance of obturation techniques in anatomical irregularities located at different thirds of the root canal system.

This study aimed to compare the quality of root canal obturation (ratio of area occupied by gutta-percha (G), sealer (S), and presence of voids (V)) in different anatomical irregularities (intercanal communications, lateral irregularities, and accessory canals) located at different thirds of the root canal system of mandibular molar replicas. Sixty-seven 3D printed replicas of an accessed mandibular molar were prepared using ProGlider and ProTaper Gold rotatory systems. Three specimens were randomly selected to be used as controls and did not receive further treatment. The rest were randomly distributed in 4 experimental groups to be obturated using either cold lateral compaction (LC), continuous wave of condensation (CW), and core-carrier obturation (ThermafilPlus (TH) or GuttaCore (GC)) (n=16 per group). AHPlus® sealer was used in all groups. The three controls and a specimen from each experimental group were scanned using micro-computed tomography. The rest of the replicas were sectioned at the sites of anatomical irregularities and examined at 30× magnification. The G, S, and V ratios were calculated dividing the area occupied with each element by the total root canal area and then compared among groups using the Kruskal-Wallis test. Voids were present in all obturation techniques with ratios from 0.01 to 0.15. CW obtained a significantly higher G ratio in the irregularity located in the coronal third (0.882) than LC (0.681), TH (0.773), and GC (0.801) (p<0.05). TH and GC achieved significantly higher G ratios in those located in the apical third (p<0.05). The worst quality of obturation was observed in the loop accessory canal with all obturation techniques. Whitin the limitations of this study, it can be concluded that CW and core-carrier obturation are respectively the most effective techniques for obturating anatomical irregularities located in the coronal and the apical third.

Evaluation of various obturation techniques with bioceramic sealers in 3D-printed C-shaped canals.

This in vitro study compared various obturation techniques with bioceramic sealers for filling C-shaped 3D-printed replicas. A mandibular molar with a C-shaped root canal with a C1 configuration was obtained. After instrumenting with M3 Pro Gold files (United Dental, Shanghai, China) up to size #30/0.04, a CBCT scan of the tooth was taken. Sixty 3D-printed replicas of the tooth were created. The samples were obturated with EndoSeal TCS sealer (E. TCS; Maruchi, Wonju, Korea) or EndoSeal MTA (E. MTA; Maruchi, Wonju, Korea) (n = 30). The samples in each group were obturated with the following techniques (n = 10): (1) single-cone technique (SC), (2) SC with ultrasonic activation (UA), and (3) cold hydraulic compaction (CHC). Following incubation, the replicas' apical, middle, and coronal thirds were inspected under a digital microscope, and the proportion of filling material and void were calculated. Also, the obturation time and sealer extrusion were recorded. Data were analyzed using ANOVA, LSD post-hoc, and the chi-square tests (α = 0.05). The results indicated that in the apical third, E. TCS-SC, E. TCS-UA, and E. MTA-UA had the lowest void percentage among groups (p < 0.05). In the middle thirds, samples obturated with E. TCS-UA showed a significantly lower void percentage among all groups (p < 0.05). However, in the coronal third, E. TCS-CHC showed the least void percentage (p < 0.05), followed by E. TCS-UA and E. MTA-CHC. The E. TCS-SC and E. TCS-UA were the least time-consuming methods (p < 0.05). Sealer extrusion significantly differed among the groups, with E. MTA-UA and E. TCS-UA showing higher incidence (p = 0.019). It was concluded that E. TCS-UA was the most convenient obturation technique. However, care must be taken when obturating the canals with high flow and ultrasonic activation near the vital anatomical landmarks.

The Effect of Adding Various Antibiotics on the Push-out Bond Strength of a Resin-based Sealer: An In Vitro Study.

AIM: This study aimed to compare the bond strength of AH Plus sealer to root canal dentin when used with or without various antibiotics including amoxicillin, clindamycin, and triple antibiotic mixture (TAM). MATERIALS AND METHODS: A total of 80 single-rooted extracted human teeth were instrumented and obturated with gutta-percha and four different sealer-antibiotic combinations (n = 20). Group I: AH Plus without any antibiotics, Group II: AH Plus with amoxicillin, Group III: AH Plus with clindamycin, and Group IV: AH Plus with TAM. After seven days, the roots were sectioned perpendicular to their long axis and 1 mm thick slices were obtained from the midroots. The specimens were subjected to a push-out bond strength test and failure modes were also evaluated. Data was analyzed using Kruskal-Wallis and Dunn's post hoc tests. RESULTS: Group IV had significantly higher bond strength compared to other groups (p ≤ 0.05). No significant differences were found between other groups. While the sealer-antibiotic groups predominantly showed cohesive failure modes, the control group displayed both cohesive and mixed failure modes. CONCLUSION: Within the limitations of this study, the addition of TAM increased the push-out bond strength of AH Plus. CLINICAL SIGNIFICANCE: Amoxicillin, clindamycin, or TAM can be added to AH Plus for increased antibacterial efficacy without concern about their effects on the bond strength of the sealer. How to cite this article: Adl A, Shojaei NS, Ranjbar N. The Effect of Adding Various Antibiotics on the Push-out Bond Strength of a Resin-based Sealer: An In Vitro Study. J Contemp Dent Pract 2024;25(3):231-235.