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This study evaluated the impact of canal irrigation using surfactants associated to NaOCl on the percentage of voids of root canal filling through micro‐computed tomographic (micro‐CT) analysis. 27 mandibular mesial roots with Vertucci type II canal configuration with isthmus were selected and scanned in a micro‐CT device. The specimens were assigned to three groups (n = 9), according to the irrigation solution during instrumentation: 2.5% NaOCl without additives (control), 2.5% NaOCl with 0.1% Benzalkonium Chloride and 2.5% NaOCl with 0.1% Tween 80. After obturation, the specimens were rescanned, and the percentage of voids were calculated. Data were analysed using one‐way ANOVA with a significance level of 5%. The percentage of voids were similar among the groups (p > 0.05). None of the specimens showed completely voids‐free areas. The addition of surfactants to NaOCl irrigation did not improve the quality of root canal filling of mandibular mesial root canals. [ABSTRACT FROM AUTHOR]

Aim: To assess the periapical alveolar bone pattern and the serum levels of proinflammatory cytokines, biochemical markers and metabolites in rats subjected to chronic alcohol and nicotine consumption and induced apical periodontitis. Methodology: Twenty‐eight male Wistar rats were divided into four groups: Control, Alcohol, Nicotine and Alcohol+Nicotine. The alcohol groups were exposed to self‐administration of a 25% alcohol solution, while the other groups were given only filtered water. The nicotine groups received daily intraperitoneal injections of a nicotine solution (0.19 μL of nicotine/mL), whereas the other groups received saline solution. Periapical lesions were induced by exposing the pulps of the left mandibular first molars for 28 days. After euthanasia, the mandibles were removed and the percentage bone volume, bone mineral density, trabecular thickness, trabecular separation and trabecular number of the periapical bone were measured using micro‐computed tomography images. Serum samples were collected for analysis of proinflammatory cytokines (IL‐1β, IL‐4, IL‐6 and TNF‐α), biochemical and metabolomic analysis. Statistical analysis was performed with a significance level of 5%. Nonparametric data were analysed using the Kruskal‐Wallis test followed by Dunn's test, while one‐way anova followed by Tukey's test was performed for parametric data. Results: The groups exposed to alcohol or nicotine consumption exhibited an altered bone pattern indicating lower bone density and higher levels of IL‐1β, IL‐6 and TNF‐α compared to the Control group (p <.05). Significant differences were observed among the groups in the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, cholesterol, triglycerides, urea, creatinine, albumin, uric acid, bilirubin and calcium. Metabolomic analysis revealed significant differences in glycine, phosphocholine, lysine, lactate, valine, pyruvate and lipids (CH2CH2CO), n(CH2) and n(CH3). Most of these parameters were even more altered in the simultaneous consumption of both substances compared to single consumption. Conclusion: Alcohol and nicotine chronic consumption altered several metabolic markers, impaired liver and kidney function, increased the production of systemic proinflammatory mediators and harmed the periapical bone microarchitecture in the presence of apical periodontitis. The simultaneous consumption of alcohol and nicotine intensified these detrimental effects. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to evaluate the volumetric change of root canal sealers through micro‐computed tomographic analysis using a novel in vivo model and to compare the results with those obtained using an ex vivo test. Methodology: Eighteen single‐rooted teeth were cut to 5 mm length from the root apex. The root canals were uniformly enlarged and filled with EndoSequence BC Sealer or AH Plus Jet root canal sealers. Samples were stored at 37°C and 95% relative humidity for 24 h and then scanned with a micro‐CT device. Twelve samples (n = 6 for each sealer) were implanted in the subcutaneous tissue of Wistar rats, while six samples (n = 3 for each sealer) were immersed in 20 mL of phosphate‐buffered saline (PBS) at 37°C at neutral pH. After 7 and 30 days, teeth were removed from subcutaneous tissue or PBS and rescanned. Statistical analysis of volume changes was performed using Shapiro–Wilk's test and independent t‐test (p <.05). Results: AH Plus Jet had smaller volume changes (−2.2 to +0.77%) than EndoSequence BC Sealer (−2.0 to +4.0%) (p <.05), in the two tested models. The volume of the root canal sealers decreased over time (p <.05), in vivo. AH Plus Jet results varied between the in vivo and ex vivo results (p <.05), while EndoSequence BC Sealer presented similar volume losses for both experimental models (p >.05). Conclusion: EndoSequence BC Sealer lost more volume than AH Plus Jet. The experimental conditions influenced the volumetric change of AH Plus Jet but not the EndoSequence BC Sealer. The ex vivo model should be further explored as a methodological alternative to assess the volumetric changes of root canal sealers without causing harm to animals. [ABSTRACT FROM AUTHOR]

This study assessed the influence of pH variation on the volumetric change of EndoSequence BC Sealer compared to AH Plus Jet. Eighteen single‐rooted teeth were uniformly prepared and filled with one of the sealers. After 24‐h storing, samples were scanned in a micro‐CT device. Then, roots were immersed in 20 ml phosphate‐buffered saline (PBS) with pH of 5, 7 or 12 at 37°C for 7 and 30 days and rescanned. Statistical analysis was performed using Shapiro–Wilk's test, one‐way ANOVA and Tukey's or Student's t‐tests (p < 0.05). Differences between sealers were observed only at neutral pH and after 30 days of acidic pH exposure, with a higher loss of EndoSequence (p < 0.05). After 7 days, alkaline pH reduced and increased the volumetric loss of EndoSequence and AH Plus, respectively, compared to neutral pH (p < 0.05). It can be concluded that the pH directly influenced the volumetric change of both tested root canal sealers in different ways. [ABSTRACT FROM AUTHOR]

Objective: This study evaluated the effect of various endodontic irrigation regimens, using NaOCl followed by different agents for smear layer removal, on the surface and interface of Biodentine with dentine. Materials and methods: Furcal perforations were produced in 60 permanent mandibular molars. The walls of the perforated area were contaminated with blood and then perforations were covered with Biodentine and the teeth were divided into six groups (n = 10). In the control group, all irrigation procedures were performed using distilled water. In the other five groups 5.25% NaOCl was used as initial irrigant followed by: distilled water (DW group); 17% ethylenediaminetetraacetic acid (EDTA group); 37% phosphoric acid (PA group); 10% citric acid (CA group); and 7% maleic acid (MA group). The specimens were analysed using scanning electron microscopy (SEM) before and after the irrigation procedure to evaluate the morphology of Biodentine on the surface. SEM images were analysed qualitatively using a score system (Score 0, no modification between initial and final images; Score 1, modification between initial and final images). Pushout bond strength test was performed 7 days after sample preparation. Data were statistically analysed using Kruskal--Wallis and Dunn tests (P < 0.05). Results: All irrigation regimens modified the topography of Biodentine. The regimens that used NaOCl/DW and NaOCl/EDTA showed significantly lower push-out bond strength values when compared to NaOCl/PA, NaOCl/CA, NaOCl/MA and control (P < 0.05). Conclusions: The regimens using NaOCl/DW or NaOCl/EDTA compromised the push-out bond strength results when compared with other groups. [ABSTRACT FROM AUTHOR]

Objective: This study assessed the push-out bond strength (POBS) of an epoxy resin-based sealer in oval-shaped root canals after a final irrigation protocol using XP-endo Finisher and ultrasonic activation. Materials and methods: Thirty oval-shaped human root canals were prepared with Reciproc R25 and a final irrigation regimen using 5.25% sodium hypochlorite and 17% ethylenediaminetetraacetic acid (EDTA) was performed. The teeth were divided into three groups (n = 10) according to the final irrigation activation technique: no activation (control), ultrasonic activation and XP-endo Finisher activation. Specimens were filled only with AH Plus sealer and the POBS test was used to measure the bond strength between the root canal dentine and AH Plus sealer. The data obtained from the POBS test were analysed using two-way analysis of variance and Tukey post-hoc tests (P < 0.05). Results: The POBS values decreased from the coronal to the apical direction (P < 0.05). There was a significant association between the activation technique and the root canal third (P < 0.05). In the coronal and middle third, XP-endo Finisher and ultrasonic activation showed higher POBS than the control group (P < 0.05). In the apical third, XP-endo Finisher showed higher POBS than ultrasonic activation (P < 0.05) and the control group (P < 0.001). Ultrasonic activation also showed higher POBS values in the apical third when compared to the control group (P < 0.05). Conclusions: The activation of root canal irrigants influenced POBS of root canal sealers in the different root thirds of oval-shaped canals. The use of XP-endo Finisher file resulted in better POBS than ultrasonic activation in the apical third. [ABSTRACT FROM AUTHOR]

Aim: This study assessed the ability of Reciproc R25 instruments in maintaining the original profile of root canal anatomy in simulated curved canals (SCC) after multiple uses. The bending resistance of R25 before and after each use was evaluated. Materials and methods: Fifty SCC manufactured in clear resin blocks and ten R25 instruments were used. Each instrument prepared five SCC with four reuses, without intermediate sterilization. The flexibility of each instrument was determined by 45-degree bending tests before and after reuse. Colour stereomicroscopic images from each block were taken at the same position before and after instrumentation. All image processing and data analysis were performed with Fiji program. Evaluation of canal transportation was obtained for straight and curved canal regions. Univariate analysis of variance and Tukey's test were used (P < 0.05). Results: No significant difference was observed in bending resistance before and after multiple uses (P > 0.05). There was no difference in canal transportation resulting from utilizing R25 instruments after five multiple uses (P > 0.05). However, canal transportation was more severe in curved canal portions than straight portions (P < 0.05). Conclusions: Bending resistance and the final shape obtained in plastic blocks following R25 instrument use did not vary significantly between the first and the fifth use. [ABSTRACT FROM AUTHOR]

This case report aimed to demonstrate the importance of cone beam computed tomography (CBCT) for the diagnosis, follow-up and treatment planning of internal root resorption (IRR). A 10-year-old male patient was referred for clinical examination, which revealed a dental fusion in the mandibular right lateral incisor (tooth 42). One year after the sectioning of the fused teeth, a well demarcated radiolucency in tooth 42 was observed by radiography, similar to IRR. CBCT scanning was performed in order to distinguish between external and internal root resorption. After the IRR diagnosis, root canal treatment was performed and no progression of the lesion was observed after 2 years. Thus, CBCT images were useful to delimit the extent of the IRR lesion, being able to identify possible communication sites with the periodontal space, and should be applied in IRR cases. [ABSTRACT FROM AUTHOR]

A root‐end filling material is required to fill the root‐end cavity without gaps or voids, to prevent root canal reinfection and to provide periapical healing. Thus, this study evaluated the volume of marginal gaps and voids of three root‐end filling materials using microcomputed tomography (micro‐CT). Thirty maxillary incisors were prepared and filled with gutta‐percha and endodontic sealer. The specimens were scanned using micro‐CT and distributed into three groups (n = 10): White MTA, MTA Repair HP, and Bio‐C Repair. The root tips were resected at 90° to the longitudinal axis and the cavity (3 mm depth) was prepared with an ultrasonic tip. The materials were handled, and the cavities were filled. The specimens were rescanned and the percentual volume of gaps and voids were analyzed. The data were analyzed using Kruskal–Wallis and Dunn tests (p <.05). No statistical difference was found in the percentage of gaps among the tested materials (p >.05). White MTA presented less voids than Bio‐C and MTA Repair HP (p <.05). The materials presented a similar percentual volume of gaps and White MTA presented less voids than other tested materials. [ABSTRACT FROM AUTHOR]

This study evaluated the ability of reciprocating glide path instruments to reach the full working length (RFWL). Thirty mesial roots of mandibular molars were matched into 2 groups (n = 15 teeth, 30 root canals), according to the system used for glide path: WaveOne Gold Glider (WOGG) and R‐Pilot. The samples with fractured instruments or when it was not possible to RFWL were scanned using micro‐computed tomography. Fractured instruments were also visualised through a scanning electron microscopy to verify the type of fracture. The parameters were compared statistically by Fisher's and chi‐square tests (P < 0.05). No instrument fractures were observed in the R‐pilot, while 2 fractures occurred in the WOGG group (P > 0.05). RFLW was achieved in 29 canals (96.66%) and 28 canals (93.33%) with R‐pilot and WOGG instruments, respectively (P > 0.05). The instruments are able to RFWL in mesial canals of mandibular molars. WOGG showed two fractures while no R‐Pilot instruments fractured. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the shaping ability of XP‐endo Shaper and Mtwo systems in oval‐shaped canals preparation by microcomputed tomography (micro‐CT) along the entire canal. The volume, surface area and percentage of unprepared area were evaluated by image processing in entire canal and apical third (5 mm). Apical transportation and centring ability were evaluated at 3, 5 and 7 mm from the apex. Forty single‐canal oval canines were paired in two groups (n = 20) according to the instrumentation system: XP‐endo Shaper and Mtwo. The teeth were scanned by micro‐CT before and after instrumentation, using a thermal vat at 37°C. The XP‐endo Shaper system was more effective in the instrumentation of oval‐shaped canals when compared to Mtwo system, resulting in greater volume increases and lower percentage of unprepared canals walls in apical region. Regarding apical transportation and centring ability, no statistical difference was observed. [ABSTRACT FROM AUTHOR]

Accumulated hard tissue debris (AHTD) in root canal irregularities may negatively impact adequate root canal disinfection. In light of this, the efficacy of passive ultrasonic irrigation (PUI) to reduce AHTD has been largely studied in in vitro studies, which have adopted different analytic methods of varying accuracy to determine the extent of AHTD more correctly. Therefore, the aim of this study was to compare how well PUI and non-activated irrigation (NAI) systems perform in reducing AHTD during final irrigation protocols, based exclusively on studies whose analyses used microCT scanning. A systematic search of the studies published up to April 2020 was performed using MeSH terms and free terms, in the following databases: PubMed, Scopus, Web of Science, BVS (Lilacs and BBO) and Embase. The inclusion criteria consisted of laboratory studies that evaluated the amount of AHTD, and compared PUI with NAI protocols using microCT analysis. The risk of bias in the selected studies was assessed critically by two reviewers. A meta-analysis was performed using the RevMan software program (P<0.05), and included studies providing the standardized mean difference (SMD), using a fixed effect model, and adopting a confidence interval of 95%. In all, 3495 studies were identified, three of which met the inclusion criteria. All three were considered as having a low risk of bias. The meta-analysis comparing the ability of PUI and NAI protocols to remove hard tissue debris showed a higher percentage of AHTD reduction (P<0.01) for PUI, with a confidence interval of 1.41 [0.79, 2.02]. The heterogeneity among the studies was 82% (I2). Considering the limitations of the present study, this systematic review and meta-analysis showed that PUI was more effective than NAI in removing hard tissue debris, based exclusively on studies that used microCT scanning to provide a more precise analysis of the two techniques used. The findings presented in the present study reinforce the concept that PUI can increase residue removal and improve the cleanliness of the root canal in endodontic treatments. [ABSTRACT FROM AUTHOR]

Copyright of Dental Press Endodontics is the property of Dental Press International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dental Press Endodontics is the property of Dental Press International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dental Press Endodontics is the property of Dental Press International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dental Press Endodontics is the property of Dental Press International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To evaluate the efficacy of a 37% phosphoric acid solution delivered by conventional irrigation, Endovac®, sonic and ultrasonic activated tips and plastic file on Ca(OH)2 removal using micro-CT. Methods: Fifty mesial roots of mandibular molars were manually instrumented. Ca(OH)2 paste was inserted into the root canal system with a 25 K-file. All teeth were scanned by micro-CT to determine the initial dressing volume. After 7 days, the Ca(OH)2 was removed with a 25 K-file and 10 mL of NaOCl. The specimens were allocated in 5 groups irrigated with phosphoric acid (n = 10): conventional irrigation (CI); Endovac (EV); Sonic irrigation (SI); Passive ultrasonic irrigation (PUI) and Plastic file (PF). The teeth were re-scanned by micro-CT. Results: The percentage volume of Ca(OH)2 removal was calculated. Data was evaluated by Kruskal-Wallis, Mann-Whitney and Wilcoxon tests (p < 0.05). PUI removed significantly more Ca(OH)2 than CI, EV and PF. Clinical Significance: The use of 37% phosphoric acid associated with PUI or SI showed a better performance on Ca(OH)2 removal compared with other agitation systems. [ABSTRACT FROM AUTHOR]

Objetivo: o objetivo do presente estudo foi avaliar in vitro a microinfiltração coronária em cavidades complexas seladas com materiais restauradores temporários (MRT). Métodos: as cavidades foram preparadas em 60 pré-molares superiores extraídos de humanos, e os espécimes foram divididos em três grupos, de acordo com o MRT utilizado: G1 = IRM; G2 = Coltosol; G3 = Fill Magic Tempo. Três dentes serviram como controle negativo e não tiveram cavidades preparadas. Antes do selamento das cavidades com o MRT, uma esponja de colágeno foi deixada dentro da câmara pulpar, para avaliação binária da penetração do corante. Dez dentes de cada grupo não foram submetidos à ação de termociclagem e força mecânica oclusal, enquanto outros dez foram submetidos a essas ações. A amostra foi imersa em corante Rodamina B a 0,5% a 37°C, por 7 dias. Resultados: todos os dentes examinados (100%), exceto os controles negativos, apresentaram infiltração pelo corante. Todos os dentes selados com Coltosol (100%) fraturaram após ensaio mecânico, enquanto aqueles com IRM e Fill Magic Tempo mantiveram-se intactos macroscopicamente. A ação ou não das intempéries térmicas e mecânicas não interferiu na penetração do corante nas amostras no presente estudo. Conclusão: nenhum dos materiais testados impediu a infiltração do corante. No entanto, o Coltosol não deve ser indicado para utilização em cavidades complexas onde há incidência de forças mastigatórias, devido ao seu alto índice de fratura. [ABSTRACT FROM AUTHOR]

Aim: The present study investigated the influence of apical periodontitis (AP) on the severity of rheumatoid arthritis (RA) using a Wistar rat model., Methodology: Forty male Wistar rats were distributed across four groups (n = 10) based on the induction of RA and AP: Control, RA, AP, and RA + AP. RA was induced through two immunisations with type II collagen emulsified in incomplete Freund's adjuvant, followed by one immunisation with complete Freund's adjuvant. After 21 days of RA induction, AP was induced by exposing the pulp of four molars. Animals were euthanized after 28 days of pulp exposure. Through the experiment, visual and behavioural assessments tracked RA development and the knees and hind paw joints were measured. Micro-computed tomography scans of knees and hind paws, as well as mandibles and maxillae, were conducted to evaluate RA severity and the presence of AP, respectively. Serum samples were collected to analyse proinflammatory cytokines (IL-1β, IL-2, IL-17, and TNF-α). Non-parametric data were analysed using the Kruskal-Wallis test followed by Student-Newman-Keuls test, while one-way anova followed by Tukey's test was performed for parametric data. A significance level of 5% was employed., Results: All molars submitted to access cavity developed AP. All joints subjected to arthritis induction developed the disease, with AP + RA demonstrating a higher arthritis severity when compared to the RA group (p < .05). RA + AP group displayed a significantly larger hind paw and knee circumference compared to the RA group (p < .05). Micro-CT images of RA and RA + AP groups revealed joints with erosions and bone deformities, with a significantly lower bone surface density, lower trabecular number and higher trabecular separation in the hind paw and a significantly lower percent bone volume and higher trabecular separation in the knees of RA + AP group compared to RA group (p < .05). RA + AP group exhibited a significantly higher level of TNF-α and a lower level of IL-2 compared to all other groups (p < .05). Both RA and RA + AP groups had significantly higher IL-17 levels (p < .05), while there was no significant difference in IL-1β levels among the groups (p > .05)., Conclusion: The findings from this study underscore a possible relationship between apical periodontitis and the exacerbation of rheumatoid arthritis., (© 2024 British Endodontic Society. Published by John Wiley & Sons Ltd.)

Statement of Problem: Prefabricated and custom glass fiber posts have been successfully used to reconstruct endodontically treated teeth. However, the performance of computer-aided design and computer-aided manufacture (CAD-CAM) milled glass fiber posts is unclear., Purpose: The purpose of this systematic review with meta-analysis was to compare the fracture and bond strength and cement layer thickness of CAD-CAM milled glass fiber posts with prefabricated or custom glass fiber posts., Material and Methods: The protocol was registered in the Open Science Framework (http://osf.io/65jm7). Two reviewers searched the PubMed/MEDLINE, Web of Science, Embase, Scopus, and ProQuest databases for articles up to September 2023. In addition, the reference lists were hand searched. A meta-analysis was performed by using the RevMan 5.4 program. The risk of bias was assessed using the RoBDEMAT tool., Results: After screening, a total of 18 studies were included. The CAD-CAM milled glass fiber posts showed higher fracture strength (P=.02; Standardized Mean Difference [SMD]: 0.57; 95% Confidence Interval [CI]: 0.07 to 1.07), bond strength (P=.010; SMD: 1.07; 95% CI: 0.26 to 1.89), and lower cement layer thickness (P=.009; SMD: -2.94; 95% CI: -5.15 to -0.73) when compared with prefabricated glass fiber posts. However, fracture strength (P=.53; SMD: 0.38; 95% CI: -0.79 to 1.54) and bond strength (P=.90; SMD: -0.05; 95% CI: -0.81 to 0.72) were statistically similar between CAD-CAM milled and custom glass fiber posts. Significant and substantial heterogeneity was observed in all meta-analyzes (P<.01; I>60%). The studies sufficiently reported most domains related to bias, except for randomization of samples, sample size rationale and reporting and operator blinding., Conclusions: CAD-CAM milled and custom glass fiber posts provide an effective and safe option for restoring endodontically treated teeth, especially for weakened teeth or enlarged root canals. However, further well-designed clinical research is recommended to strengthen these findings., (Copyright © 2024 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

This study evaluates the effect of two in-office bleaching agents with different compositions on the bond strength to enamel surface. Fifty bovine teeth were divided into five groups (n = 10 teeth per group), according to the bleaching agent used and the time elapsed to perform the restorative procedures: restorative procedures performed without bleaching (control group); bleaching with 35% hydrogen peroxide (HP), with restorative procedures 24 hours or 7 days after bleaching (HP/24h and HP/7d groups, respectively); and bleaching with 35% HP with calcium compost, with restorative procedures 24 hours or 7 days after bleaching (HP AutoMixx/24h and HP AutoMixx/7d groups, respectively). The specimens were stored at 37°C in artificial saliva. Restored teeth were submitted to a micro-shear bond strength test. The specimens were analyzed using a stereoscope to determine the fracture pattern, classified as adhesive, cohesive, or mixed. The results of the bond strength test were evaluated by analysis of variance, with significance set at P < .05. The groups showed similar bond strength values without significant difference among them (P > .05). There was a predominance of the adhesive-type fracture pattern in all groups. The bleaching agents with different compositions showed similar bond strength values when the restoration was performed 24 hours and 7 days after bleaching, and the results were similar to the control group.

Background: The present study assessed the quality of images and the presence of marginal gaps on cone-beam computed tomography (CBCT) images of teeth restored with all-ceramic and metal-ceramic crowns and compared the gap sizes observed on CBCT images with those obtained on micro-CT images., Methods: Thirty teeth restored with metal-ceramic and all-ceramic crowns, properly adapted and with gaps of 0.30 and 0.50 mm, were submitted to micro-CT and CBCT scans. Linear measurements corresponding to the marginal gap (MG) and the absolute marginal discrepancy (AMD) were obtained. The objective assessment of the quality of CBCT images was performed using the contrast-to-noise ratio (CNR), and the subjective assessment was defined by the diagnoses made by five examiners regarding the presence or absence of gaps., Results: The measurements were always higher for CBCT, with a significant difference regarding AMD. No significant difference in image quality was observed using CNR between the crowns tested. Low accuracy and sensitivity values could be observed for both crowns., Conclusion: Marginal mismatch measures were overestimated in CBCT images. No difference in image quality was observed between the crowns. The correct diagnosis of gaps was considered low, irrespective of crown type and gap size., Competing Interests: The authors do not have any financial interests in the companies whose materials are included in this article. The authors do not have any competing interests., (©2022 The Author(s).)

This study evaluated the antimicrobial effectiveness of 6.5% Vitis vinifera grape seed extract (GSE) against Enterococcus faecalis biofilm using confocal laser scanning microscopy (CLSM). Saline solution (SS), 5.25% sodium hypochlorite (NaOCl) and 2% chlorhexidine (CHX) were used for comparison. Dentin discs were inoculated with E. faecalis strain establishing a 3-week-old biofilm. Discs (n = 10) were exposed to 5.25% NaOCl, 2% CHX, 6.5% GSE and SS (negative control) for 10 min. Discs were stained with the fluorescent LIVE/DEAD-BacLight™ dye and analysed using CLSM. The proportion of dead cells in biofilm was analysed using one-way anova and Tukey tests (P < 0.05). A higher proportion of dead cells was found in GSE group compared with CHX and SS (P < 0.05). NaOCl group was associated with the highest proportion of dead cells (P < 0.05). GSE presented antimicrobial activity against E. faecalis; however, NaOCl was the most effective irrigant solution. GSE was more effective than CHX and SS., (© 2019 Australian Society of Endodontology Inc.)

The aim of this study was to evaluate the root canal configuration of maxillary premolars using cone-beam computed tomography (CBCT). CBCT images of 999 maxillary premolars from a database were analysed to determine the frequency of the number of roots, root canals and Vertucci's classification. The associations among these variables were evaluated by Chi-square test (P < 0.05). In the first premolars, 42.2% of single-rooted teeth had a type II configuration, whereas 98.7% of 2-rooted teeth showed type IV. In the second premolars, type I was the most prevalent (49.9%). The presence of two roots was more prevalent in first premolars, and the presence of one root was more prevalent in second premolars (P < 0.05). Male patients had a higher percentage of two roots compared with female patients (P < 0.05). Type IV and I was more prevalent in first and second premolars respectively (P < 0.05). There was a high frequency of 2-rooted and single-rooted teeth among maxillary first and second premolars respectively., (© 2018 Australian Society of Endodontology Inc.)

This study evaluated the effect of previous irrigation with chlorhexidine (CHX) on the bond strength of a calcium silicate-based material, Biodentine, when used for furcal repair. Furcal perforations were produced in 30 extracted mandibular molars. Teeth were divided into 3 groups according to the irrigant used: distilled water (DW), CHX followed by DW (CHX), and CHX followed by ethylenediaminetetraacetic acid (EDTA) and DW (CHX/EDTA). Biodentine was used to repair the perforations. A push-out bond strength test was performed after 7 days, and data were statistically analyzed using Kruskal-Wallis and Dunn tests (P < 0.05). The CHX/EDTA group showed significantly lower values than the DW and CHX groups (P < 0.05). The failure mode of the DW group was mainly mixed, while that of the CHX group was cohesive. The CHX/EDTA group exhibited adhesive and mixed failures. Irrigation with CHX prior to furcation repair did not result in a statistically significant difference, compared to the use of DW, in the push-out bond strength of Biodentine., Competing Interests: The authors report no conflicts of interest pertaining to any of the products or companies discussed in this article.

Context: The lack of thorough knowledge regarding morphological and anatomical variations of the root canal system can result in failure to identify all root canals and lead to inadequate instrumentation and consequent failure of the endodontic treatment., Aims: The aim of the study was to evaluate the anatomy of single-rooted mandibular canines using micro-computed tomography (micro-CT)., Subjects and Methods: Eighty mandibular canines were scanned by micro-CT to determine anatomic parameters: Vertucci's classification, number of lateral canals, roundness, and minor and major diameters. The shape of root canal orifices, volume, surface area, and convexity structure model index (SMI) were also evaluated., Analysis Used: The CTAn and CTvol software were used to three-dimensional and morphometric analysis., Results: All canals were classified as Vertucci Type I. Lateral canals were verified in 42.4% of the roots, in apical third. The canal diameters were decreased near the apex. The cross sections at the cementoenamel junction and 1 mm from the apex were oval in 38.3% and 79.4% of the canals, respectively. The mean canal volumes and surface areas were 11.48 ± 4.41 mm 3 ≥ and 67.29 ± 19.18 mm 2 , respectively. The SMI values indicated that mandibular canine was approximately rod like., Conclusions: The morphology of the root canal of single-rooted canines varied widely at different root levels., Competing Interests: There are no conflicts of interest.

Objective: To evaluate the fracture resistance of different intra-radicular post systems in flared root canals., Methods: Sixty human canines were used. The coronal portion was removed and the root length was standardized at 17 mm. Canals were prepared and filled with gutta-percha/AH Plus sealer. Roots were embedded in self-polymerising acrylic resin blocks. According to the material used, the teeth were randomly divided into three groups (n=20): glass fibre post (GFP): GFP and Z350 resin composite core; pre-fabricated metal post (PMP): PMP and Z350 resin composite core; and cast metal core (CMC): CMC with silver-tin alloy. Coronal reconstruction involved fabrication of metal copings. Samples were submitted to mechanical compression testing at 45º in a universal test machine. Fracture pattern was evaluated under a stereoscope. The fracture strength values were submitted to one-way analysis of variance (ANOVA) and Tukey tests (α=0.05)., Results: There was no statistically significant difference between the resistance values among groups (P=0.193). With regard to fracture pattern, GFP showed 55% and PMP 45% of Type I fractures, which considered repairable or favourable, whereas MCC presented 50% of Type V, which was considered irreparable or unfavourable., Conclusion: Glass fibre and pre-fabricated metal posts have good fracture resistance to compression and may be used for restoring flared root canals, since they presented fractures mainly involving the filling core, thus facilitating later repair., Competing Interests: Conflict of Interest: No conflict of interest was declared by the authors., (Copyright: © 2020 European Endodontic Journal.)