Clinical and laboratorial performance of rehabilitation of endodontically treated teeth: A systematic review.

OBJECTIVE: This systematic review aimed to analyze the clinical (survival rate, failure risk, or fracture) and laboratory performance (fracture mode or failure) of rehabilitations of endodontically treated teeth, with and without posts. MATERIALS AND METHODS: A systematic search was conducted in the Pubmed, Scopus, Web of Science, Embase, Cochrane Library, and OpenGrey databases up to March 2023, according to PRISMA guidelines. In vitro and clinical studies that compared the clinical and laboratory performance of endodontically treated teeth with and without intraradicular posts were included. Studies selection, data extraction, and risk of bias analysis were performed. RESULTS: Thirty-one in vitro and 7 clinical studies were included. For in vitro studies, fiberglass post (n = 24) was the most mentioned. The follow-up time of the clinical studies ranged from 1 to 17 years, with the fiber-reinforced composite post (n = 3) being the most evaluated, and only failure risk proved to be more favorable for using intraradicular posts. CONCLUSION: Rehabilitations of endodontically treated teeth with and without intraradicular retainers showed no difference in fracture resistance and failure mode, evaluated by in vitro studies. Clinical studies showed no difference in survival rate, but failure risk proved to be more favorable for the use of posts. CLINICAL SIGNIFICANCE: This analysis revealed significant variability between results, however, most laboratory and clinical studies revealed no difference with using the post. Furthermore, it is important to emphasize the need to evaluate the coronary remnant and the general characteristics of the tooth in each situation.

A new method of adhesive system application improves the bond strength between fiber post and root dentin

Abstract This study evaluated a new method of adhesive system application on the bond strength between fiber post and root dentin using two adhesive systems. The canals of sixty bovine incisors were prepared and obturated. The roots were divided into six groups (n=10) according to the adhesive system (Clearfil SE - CSE and Single Bond Universal - SBU) and the application strategy (microbrush - MB; rotary brush - RB; and ultrasonic tip - US). The glass fiber posts were cemented with resin cement (RelyX ARC). The roots were sectioned perpendicularly to their long axis, and three slices per root were obtained. Previously to the push-out test, confocal laser scanning microscopy (CLSM) was performed to illustrate the interfacial adaptation of the cement to the root canal walls. Failure patterns were analyzed with 40x magnification. Shapiro-Wilk indicated a normal distribution of the data. The bond strength values were compared using one-way ANOVA and Tukey's tests. Student's T test analyzed the differences between the adhesive systems within each third and protocol. A significance level of 5% was used. CSE with RB showed higher mean bond strength values compared to MB (conventional technique) (P < 0.05). US application resulted in intermediate bond strength values for CSE (P > 0.05). The application of SBU using RB generated higher mean bond strength values compared to MB and US (P < 0.05). Adhesive failures were predominant (65.5%). CSE and SBU application with the new rotary brush improved the bond strength of fiber posts to root dentin compared to the conventional strategy.

Resumo Este estudo avaliou o efeito de um novo método para aplicação do sistema adesivo na resistência de união entre pino de fibra e dentina radicular usando dois sistemas adesivos. Os canais de sessenta incisivos bovinos foram preparados e obturados. As raízes foram divididas em seis grupos (n=10) de acordo com o sistema adesivo (Clearfil SE - CSE e Single Bond Universal - SBU) e com a estratégia de aplicação (microbrush - MB, escova rotatória - RB e inserto ultrassônico - US). Os pinos de fibra foram cimentados utilizando cimento resinoso (RelyX ARC). As raízes foram seccionadas perpendicularmente ao seu longo eixo e três fatias foram obtidas. Previamente ao teste de push-out, foi realizada microscopia de varredura confocal a laser para ilustrar a adaptação interfacial do cimento às paredes do canal radicular. Os padrões de falha foram analisados com magnificação de 40x. O teste de Shapiro-Wilk indicou distribuição normal dos dados. Os valores de resistência de união foram comparados usando o teste ANOVA de uma via e post hoc de Tukey. As diferenças entre os sistemas adesivos em cada terço e de acordo com cada protocolo foram analisadas pelo teste T de Student. O nível de significância foi de 5%. CSE aplicado com RB apresentou maiores valores médios de resistência de união do que quando aplicado com MB (técnica convencional) (P<0,05). Aplicação com US apresentou valores intermediários de resistência de união para o CSE (P>0,05). A aplicação do SBU utilizando RB gerou maiores valores médios de resistência de união comparados com MB e US (P<0,05). Falhas adesivas foram predominantes (65,5%). A aplicação do CSE e SBU com a nova escova rotatória melhorou a resistência de união dos pinos de fibra à dentina radicular comparados com a estratégia convencional.

Clinical longevity of metallic versus fiberglass intraradicular posts: a systematic review / Longevidade clínica de pinos intraradiculares metálicos versus de fibra de vidro: uma revisão sistemática

Objective: This systematic review aims to compare the clinical longevity of metallic and fiberglass intraradicular posts in teeth with severely compromised crowns, utilizing randomized clinical trials and case reports published in the last eleven years. Material and Methods: The research was conducted on PubMed, Medline, Lilacs, and BBO databases using the first search strategy with the descriptors 'dental posts,' 'longevity,' 'fiberglass-reinforced posts' or 'metallic posts.' The second search strategy involved analyzing the references of articles identified by the first search. Both studies were carried out with stringent inclusion and exclusion criteria. Results: No statistically significant and clinically relevant differences in longevity were observed between metallic and fiberglass posts. Conclusion: The clinical success and durability of the restorative procedure using intraradicular posts primarily depend on the remaining amount around the post (ferrule), the type and position of the tooth in the arch (impacting the masticatory forces exerted on the restored tooth), and the correct application of the cementation technique. It is noteworthy that fiberglass posts offer substantial advantages by presenting a modulus of elasticity similar to dental structure, ensuring a more homogeneous distribution of masticatory forces and reducing the risk of fractures. These findings have practical implications for material selection in restorative procedures involving intraradicular posts.(AU)

Objetivo: Esta revisão sistemática visa comparar a longevidade clínica de pinos intrarradiculares metálicos e de fibra de vidro em dentes com coroas severamente comprometidas, através de estudos clínicos randomizados e relatos de casos, publicados nos últimos onze anos. Material e Métodos: A pesquisa foi conduzida nas bases de dados PubMed, Medline, Lilacs e BBO, utilizando a primeira estratégia de busca com os s 'pinos dentais' e 'longevidade' e 'pinos reforçados com fibra de vidro' ou 'pinos metálicos'. A segunda estratégia de busca consistiu na análise das referências dos artigos identificados pela primeira estratégia. Ambos os estudos foram delineados com critérios rigorosos de inclusão e exclusão. Resultados: Não se constataram diferenças estatisticamente significativas e clinicamente relevantes na longevidade entre pinos metálicos e de fibra de vidro. Conclusão: O êxito clínico e a durabilidade do procedimento restaurador empregando pinos intrarradiculares dependem primordialmente da quantidade de remanescente ao redor do pino (férula), do tipo e posição do dente na arcada (o que impacta nas forças mastigatórias exercidas sobre o dente restaurado) e da aplicação correta da técnica de cimentação.Destaca-se que o pino de fibra de vidro oferece vantagens substanciais ao apresentar módulo de elasticidade similar à estrutura dentária, assegurando uma distribuição mais homogênea das forças mastigatórias e reduzindo o risco de fraturas (AU)

Looking for related posts on GitHub discussions.

Software teams increasingly adopt different tools and communication channels to aid the software collaborative development model and coordinate tasks. Among such resources, software development forums have become widely used by developers. Such environments enable developers to get and share technical information quickly. In line with this trend, GitHub announced GitHub Discussions-a native forum to facilitate collaborative discussions between users and members of communities hosted on the platform. Since GitHub Discussions is a software development forum, it faces challenges similar to those faced by systems used for asynchronous communication, including the problems caused by related posts (duplicated and near-duplicated posts). These related posts can add noise to the platform and compromise project knowledge sharing. Hence, this article addresses the problem of detecting related posts on GitHub Discussions. To achieve this, we propose an approach based on a Sentence-BERT pre-trained general-purpose model: the RD-Detector. We evaluated RD-Detector using data from three communities hosted in GitHub. Our dataset comprises 16,048 discussion posts. Three maintainers and three Software Engineering (SE) researchers manually evaluated the RD-Detector results, achieving 77-100% of precision and 66% of recall. In addition, maintainers pointed out practical applications of the approach, such as providing knowledge to support merging the discussion posts and converting the posts to comments on other related posts. Maintainers can benefit from RD-Detector to address the labor-intensive task of manually detecting related posts.

Effect of irrigation protocols on smear layer removal, bond strength and nanoleakage of fiber posts using a self-adhesive resin cement.

Objectives: This study aimed to investigate the effect of the application method of 2% chlorhexidine (CHX) and its influence on the adhesion of fiberglass posts cemented with a self-adhesive resin cement. Materials and Methods: Sixty human mandibular premolars were endodontically treated and divided into 5 groups (n = 12), according to the canal irrigant and its application method: 2 groups with conventional syringe irrigation (CSI)-2.5% sodium hypochlorite (NaOCl) (control) and 2% CHX- and 3 groups with 2% CHX irrigation/activation-by passive ultrasonic irrigation (PUI), Easy Clean file, and XP-Endo Finisher file. Two roots per group were evaluated for smear layer (SL) removal by scanning electron microscopy. For other roots, fiber posts were luted using a self-adhesive resin cement. The roots were sectioned into 6 slices for push-out bond strength (BS) (7/group) and nanoleakage (NL) (3/group). Data from SL removal were submitted to Kruskal-Wallis and Student-Newman-Keuls tests (α = 0.05). Data from BS and NL were evaluated by 2-way analysis of variance and Tukey's test (α = 0.05). Results: For SL removal and BS, the CHX irrigation/activation promoted better values than CSI with CHX (p < 0.05), but it was not significantly different from CSI with NaOCl (p > 0.05). For NL, the lowest values were obtained by the chlorhexidine irrigation/activation groups (p < 0.05). Conclusions: Active 2% CHX irrigation can be used to improve the post space cleaning and adhesion before fiber post cementation with self-adhesive resin cements.

Bond Strength and Failure Mode of Glass Fiber Posts with Different Surface Treatments Prior to Silanization: An In Vitro Comparative Study.

Aim: The use of chemical agents in the surface treatment of glass fiber posts can improve their bond strength to the root canal. The aim of this study was to assess the bond strength and failure mode of glass fiber posts that received different surface treatments prior to silanization. Materials and Methods: In this cross-sectional and in vitro experimental study, 50 human lower premolar roots were randomly divided into five groups and subsequently prepared to receive the cementation of a fiberglass post prior to silanization. They were distributed as group 1 (with 24% hydrogen peroxide), group 2 (with 37% phosphoric acid), group 3 (with 1.23% acidulated phosphate fluoride for 2 minutes), group 4 (with 1.23% acidulated phosphate fluoride for 6 minutes), and group 5 (without pretreatment). After cementation, the roots were sectioned into two discs for each cervical, middle, and apical region. Bond strength was assessed using the push out technique. Adhesive, mixed, and cohesive failure modes were also assessed. For data analysis, ANOVA and Tukey's post hoc tests were used, as well as Pearson's chi-square test. A significance of P < 0.05 was considered in all statistical analyses. Results: When comparing the bond strength of root regions, significant differences were obtained in groups pretreated with phosphoric acid (P = 0.018) and acidulated phosphate fluoride for 2 and 6 minutes (P = 0.001 and P = 0.000, respectively). Furthermore, significant differences were obtained between posts treated only with silane and those that received phosphoric acid pretreatment (P = 0.006) and acidulated phosphate fluoride for 6 minutes (P = 0.001). Significant association of mixed failure mode was observed with hydrogen peroxide (P = 0.014) and phosphoric acid (P = 0.006) pretreatments. Cohesive failure was significantly associated with acidulated phosphate fluoride pretreatment for 2 minutes (P = 0.032) and with posts that did not receive treatment prior to silanization (P = 0.000). Conclusion: Posts treated only with silane and pretreated with hydrogen peroxide and acidulated phosphate fluoride for 2 minutes presented significantly higher bond strength with respect to those pretreated with phosphoric acid and acidulated phosphate fluoride for 6 minutes. However, acidulated phosphate fluoride for 2 minutes and silane were associated with a better bonding type.

Overview and characterization of penile cancer content across social media platforms.

Background: Social media platforms (SMP) are an emerging resource that allows physicians, patients, and families to converse on cancer prevention, diagnosis, and treatment. We aimed to characterize penile cancer (PC) content shared on SMP. Methods: We searched PC posts on Twitter, Facebook, and Instagram from July 1st, 2021, through June 30th, 2022. Two independent, blinded reviewers analyzed the hashtags: #PenileCancer, #PenileCancerAwareness, and #PenileNeoplasm. Descriptive statistics were used for posts characterization, Pearson´s correlation coefficient for associations, and Cohen's weighted kappa coefficient for inter-rater agreement rate. Results: A total of 791 posts were analyzed, with Twitter accounting for 52%, Facebook for 12.2%, and Instagram for 35.5%, and. Most posts originated from high-income countries, such as the United Kingdom (48.8%). We found no correlation between the number of posts with PC incidence (p = 0.64) or users on SMP (p = 0.27). Most accounts were classified as "support and awareness communities" (43.6%) and "physicians and clinical researchers" (38.2%). Urology was the most common medical specialty to post (60.9%), followed by oncology (11.3%). Most posts were classified as "prevention and awareness for users" (45.1%). Global inter-reviewer agreement rate was almost perfect (k=0.95; p ≤ 0.01). On Twitter, "physicians and clinical researchers" shared more content on "treatment updates and medical papers published in medical journals," while on Facebook and Instagram, "support and awareness communities" focused on "personal and support comments." Conclusion: Overall, the number of PC posts was low compared to other neoplasms across the SMP evaluated in this study. "Physicians and clinical researchers" shared more content on Twitter, while "support and awareness communities" on Facebook and Instagram. Encouraging the use of a common SMP among the medical community and general users could lead to a more effective communication between physicians, patients, and support groups, and to increased awareness of PC.

Effect of root perforation repair with mineral aggregate-based cements on the retention of customized fiberglass posts.

The purpose of this study was to investigate whether the root perforation repair with mineral aggregate-based cements affects the retention of customized fiberglass posts to bovine intraradicular dentin. Sixty-four bovine mandibular incisors had their root canals endodontically treated and prepared for fiberglass posts luting. Teeth were randomly distributed into four groups (n = 16), according to the cement used for the perforations repair (MTA HP; calcium aluminate cement-CAC; and CAC + calcium carbonate nanoparticles-nano-CaCO3) and control group (no perforation). The groups were redistributed according to the fiberglass posts luting protocol (n = 8): total-etching (TE) (MTA HP/TE; CAC/TE; CAC + CaCO3/TE and control/TE) and self-etching (SE) (MTA HP/SE; CAC/SE; CAC + CaCO3/SE and control/SE). Roots were sectioned into 1.3 mm-thick dentin slices obtaining samples that were submitted to the push-out test in Universal Testing Machine (Instron, Model 4444-0.5 mm/min). The fractured samples were analyzed under stereomicroscope and Scanning Electron Microscope (SEM). CAC/TE and CAC/SE groups had significant difference between the cervical and middle thirds (p < 0.05). When the root thirds were not considered, CAC/SE had the lowest bond strength and differed statistically from CAC/TE and CAC + CaCO3/TE groups, which had the highest mean bond strength values (p < 0.05). The root perforations repair did not affect the bond strength of resin cement/customized fiberglass posts to bovine dentin. The increase in bond strength is luting protocol dependent.

Influence of customization and light-curing device on the bond strength of glass fiber posts - in vitro study / Influência da reanatomização e do aparelho fotopolimerizador na resistência de união de pinos de fibra de vidro - estudo in vitro

Introduction: Endodontically treated teeth are usually affected by extensive structure loss requiring the use of intraradicular posts to provide retention and restoration. Objective: An in vitro assessment was performed on the bonding of glass fiber posts to the root dentin. Material and method: Ninety (n = 10) single bovine roots were used in a 3 x 3 x 3 factorial study with subdivided plots: post customization varying the presence and type of resin (without customization, conventional resin, and Bulk Fill resin), light-curing device (Valo, Radii-Cal, Rainbow), and root third (cervical, middle, and apical). Result: For the customization factor, Tukey's test (5%) showed the superiority of the Bulk Fill (8.16 MPa) and Z350 (7.40 MPa) groups compared to the control group (4.92 MPa), without differing from each other. All light-curing devices differed, showing the superiority of Valo (9.36 MPa), Radii (6.96 MPa) as an intermediate, and the inferiority of Rainbow (4.17 MPa). The cervical root third (7.81 MPa) was superior, the apical third was inferior (5.80 MPa), and the middle third (6.88 MPa) was an intermediate without differing from the others. Conclusion: The customization of glass fiber posts increases the bond strength to the root dentin, regardless of the resin used. There was a compromise in the apical third and when using light-curing devices with lower light intensity.

Introdução: Dentes com extensa perda de estrutura podem comprometer a retenção das restaurações ao remanescente dental, onde pinos intraradiculares são indicados. Objetivo: Avaliou-se in vitro a união de pinos de fibra de vidro à dentina radicular em função de diferentes modos de reanatomização, fotopolimerizadores e regionalização radicular. Material e método: Noventa (n=10) raízes bovinas uniradiculares foram usadas num estudo fatorial 3 x 3 x 3 com parcelas subdivididas: Reanatomização do pino, variando a presença e tipo de resina (Sem reanatomização, Resina Convencional e Resina Bulkfill); Fotopolimerizador (Valo, Radii-cal, Rainbow); e Terço radicular (cervical, médio e apical). Resultado: O teste de Tukey (5%) evidenciou para o Fator Reanatomização superioridade dos grupos BulkFill (8.16MPa) e Z350 (7.40MPa) ao grupo Controle (4.92MPa), sem diferirem entre si. Todos os fotopolimerizadores diferiram entre si, com superioridade de Valo (9.36MPa), Radii (6.96MPa) intermediário, e inferioridade de Raiwbow (4.17MPa). O terço radicular cervical (7.81MPa) foi superior e o apical inferior (5.80MPa), com o terço médio (6.88MPa) intermediário e sem diferir dos demais. Conclusão: Conclui-se que a reanatomização de pinos de fibra de vidro aumenta a resistência de união à dentina radicular, independentemente da resina utilizada, havendo prejuízo no terço apical e quando são empregados fotopolimerizadores com menor intensidade luminosa.

Influência da férula na resistência à fratura de restaurações com utilização ou não de retentores intrarradiculares em dentes tratados endodonticamente: uma revisão da literatura / Influence of the ferrule on the fracture resistance of restorations with or without the use of intraradicular posts in endodontically treated teeth: a literature review

Objetivo: realizar uma revisão de literatura narrativa sobre a importância e a influência do efeito férula na resistência à fratura de restaurações em dentes tratados endodonticamente com utilização ou não de retentores intrarradiculares. Metodologia: Foram utilizados os seguintes descritores indexados no DeCS (Descritores em Ciências da Saúde): "Férula", Prótese Dentária", "Falha da Restauração Dentária", "Técnica de Retentor Intrarradicular" e "Pinos de Retenção Dentária" para busca nas bases de dados PubMed, Embase, Lilacs, Web of Science, Scopus e Cochrane Library. Resultados: Os dados da maioria dos estudos in vitro ou in vivo incluídos nesta revisão sugerem o uso da férula para aumento da resistência à fratura e longevidade dos dentes tratados endodonticamente. Tem sido recomendada a confecção de uma férula com altura uniforme de 2 mm e espessura superior a 1,5 mm. Conclusão: O uso de retentores radiculares foi indicado pela maioria dos trabalhos, sendo geralmente recomendados os pinos de fibra de vidro ao invés de núcleos metálicos fundidos para minimizar os riscos de fratura radicular em razão do módulo de elasticidade semelhante à dentina, além de possibilidade de retratamentos em casos de falhas adesivas. Apesar disso, ainda são necessários estudos clínicos com acompanhamento a longo prazo para avaliar a longevidade das restaurações de dentes tratados endodonticamente utilizando pinos de fibra de vidro sem ou com a presença de férula em diferentes espessuras e alturas.

Objective: This study aimed to conduct a narrative literature review on the importance and influence of the ferrule effect on the fracture resistance of restorations in endodon-tically treated teeth with or without the use of intraradicular posts. Methodology: The following descriptors indexed in the DeCS (Health Sciences Descriptors) were used: "Ferrule", Dental Prosthesis", "Dental Restoration Failure", "Post and Core Technique", and "Dental Posts", to search on the databases of PubMed, Embase, Lilacs, Web of Science, Scopus, and Cochrane Library data. Results: Data from most of the in vitro or in vivo studies included in this review suggest the use of the ferrule to increase fracture resistance and longevity of endodontically treated teeth. It has been recommended to make a ferrule with a uniform height of 2 mm and a thickness greater than 1.5 mm. Conclusion: The use of intraradicular posts was indicated by most studies, and fiberglass posts are generally recommended instead of cast metal cores to minimize the risk of root fracture due to the modulus of elasticity similar to dentin, in addition to the possibility of retreatments in ad-hesive failure cases. Despite this, clinical studies with a long-term follow-up are essential to evaluating the longevity of restorations of endodontically treated teeth using fiberglass posts without or with the presence of ferrule in different thicknesses and heights.

Comparing Techniques for Removing Fiber Endodontic Posts: A Systematic Review.

AIM: This systematic review aimed to establish the available techniques for fiber post removal, pointing out where each method stands out evaluating its advantages, and where they fall short indicating the possible harmful effects. MATERIALS AND METHODS: This systematic review was registered in PROSPERO (CRD42020193799). A broad search of the electronic databases PubMed, Web of Science, Scopus, and Virtual Health Library was carried out before April 27, 2020, for in vitro studies about techniques for removing fiber posts luted with resin cements of endodontically treated teeth. The methodological quality of included studies was evaluated based on the critical assessment tool for in vitro studies. RESULTS: Thirteen articles were selected and included after applying the inclusion and exclusion criteria. All included studies received an assessment of methodological quality between high and moderate. Most studies used ultrasonic inserts as a strategy to remove fiber posts, manufactured removal kits and drills were also widely used, only one study evaluated the removal capacity of the Er:YAG laser. Ultrasonic inserts seem to lead to a greater working time for removal of the fiber post, tend to generate significant volume changes in the root structure and increase the temperature on the root canal and clean the root canal walls further. CONCLUSION: Although the results tend to show greater agility in removing fiber posts with manufactured removal kits and the ultrasonic inserts seem to work better in removing fiber remains and luting agent, there is still no consensus in the literature as to which technique is the best. CLINICAL SIGNIFICANCE: In some cases, clinicians may be faced with the need to remove fiber posts in order to regain access to the root canal due to the need for endodontic retreatment which directly implies the search for the most appropriate removal technique. How to cite this article: Purger LO, Tavares SJO, Martinez RLCH, et al. Comparing Techniques for Removing Fiber Endodontic Posts: A Systematic Review. J Contemp Dent Pract 2021;22(5):587-595.

Resistance to fracture of intraradicular posts made of biological materials.

BACKGROUND: The aim was to analyze the fracture resistance of human teeth treated endodontically and restored with posts made of bovine dentin, human dentin, or glass fiber, and to evaluate the fracture pattern. METHODS: Cylindrical posts of 1.5 mm in diameter cemented to the roots of human maxillary canines presented a length of 15 mm, cervical diameter of 5-5.5 mm in the mesiodistal direction, and 7-7.5 mm in the vestibule-palatal direction. The groups studied were: Group I-10 glass fiber posts; Group II-10 human dentin posts; Group III-10 bovine dentin posts (self-adhesive resin cement); and Group IV-10 bovine dentin posts (resin-modified glass-ionomer cements). The coronal part of tooth was restored with a standardized core build-up using composite. All of the groups were submitted to a compression force test and the resistance to fracture was verified using a universal testing machine. The fracture pattern was likewise evaluated. RESULTS: The values of resistance to fracture were: 723.3N in group I, 561.5N in group II, 556.6N in group III, and, 613.27N in group IV. However, no statistically significant difference was observed among the groups. The fractures in groups I and II were most commonly found in the middle/apical third and were considered irreparable. For restored teeth in group III, half of the fractures appeared in the cervical third and were reparable. In group IV, all of the fractures were reparable, with the majority in the cervical thirds. CONCLUSION: Bovine dentin can be used as intraradicular post to substitute human dentin and glass fiber posts. The greater the malleability of the post, the greater the chances of survival of the teeth when subjected to fracture testing.

Effect of different intraradicular posts in the dimensions of root canal computed tomography images.

OBJECTIVES: To evaluate the effect of different intraradicular posts on the dimensions of computed tomography (CT) images in cone-beam and fan-beam equipment. MATERIALS AND METHODS: : A total of 15 root canals of bovine teeth were instrumented up to a file #50 and root-filled by the active lateral condensation technique. The teeth were randomly divided into three groups, according to the type of intraradicular post: 1) tight fiberglass post; 2) anatomical fiberglass post; and 3) metal post. The root canals were desobturated in 10 mm and tomographic images were acquired in two devices, a cone-beam and fan-beam equipment. Then, the intraradicular posts were cemented using an automix self-conditioning and self-adhesive resin cement, and the final acquisitions of the CT images were performed for analysis. The diameter of the canal was compared before and after cementation of the intraradicular posts. The t-test was used between the initial and final measurements of each tomograph and also between the cone-beam and fan-beam tomographs (α = 0.05). RESULTS: The anatomical fiberglass post presented the smallest dimensional change among the initial and final measurements, followed by the tight fiberglass post, with the metal post being the material that showed the most considerable dimensional difference in the cone-beam. CONCLUSION: All of the intraradicular posts used promoted a change in the size of the CT image. The fan-beam scanner promoted greater dimensional change in the images.

Assessment of the Ability of Different Cleaning Protocols to Remove Eugenol-based Endodontic Sealer from the Root Dentin.

AIM: The aim of this study is to assess three protocols for removing a eugenol-based filling endodontic sealer from root dentin and the bond strength of fiberglass posts luted with resin cement. MATERIALS AND METHODS: Sixty single-rooted bovine teeth were prepared and filled with the Endofill endodontic sealer and gutta-percha cones. After 7 days, 9 mm of the filling was removed and divided into five groups (n = 12) according to the cleaning protocol: G1 (negative control), unfilled; G2 (positive control), saline solution; G3, 95% alcohol; G4, amyl acetate; and G5, Largo bur. The canals were hybridized and fiberglass posts were luted with resin cement. They were cross-sectioned in slices of 1 mm and subjected to the push-out test. The other samples were sectioned longitudinally and visualized in a scanning electron microscope (SEM), and the existing chemical elements were quantified by energy dispersive spectroscopy (EDS). The statistical analysis used variance analysis (ANOVA)-one way and Fisher's test, at a 5% significance level. RESULTS: The 95% alcohol was more effective for cleaning the canal, resulting in a clean dentinal surface and bond strength statistically similar to the negative control. The Largo bur was also statistically similar to the negative control, with only a few debris impregnated on the wall. Amyl acetate showed more sealer residues on the canal walls, with a consequent lower bond strength value than the other groups, only higher than the positive control. CONCLUSION: The 95% alcohol and Largo burs may be used after removing the canal filling, so that the bond strength is improved when using the eugenol-based sealer.

Nueva técnica de reconstrucción postendodóncica: resina bulk-fill intraconducto vs postes de fibra de vidrio / New postendodontic reconstruction technique: bulk-fill intracanal resin vs glass fiber posts

Introducción: El uso de postes de fibra de vidrio es el método actual más utilizado para la reconstrucción postendodóncica. Sin embargo, su adhesión sigue siendo impredecible debido al control limitado de su técnica de cementación. Las resinas bulk-fill revelan valores de fuerza flexural similares a la dentina y su empleo en la reconstrucción postendodóncica podría ser una alternativa viable y conservadora. Objetivo: Comparar tres técnicas de reconstrucción postendodóncica al medir su resistencia a fuerzas de desalojo, clasificar el tipo de fractura y falla adhesiva, evaluar su costo y tiempo de trabajo. Material y métodos: Se realizan 18 muestras divididas en tres grupos: grupo 1: poste más cemento de un paso, grupo 2: poste más cemento de tres pasos y grupo 3: reconstrucción postendodóncica con resina bulk-fill. Resultados: En la evaluación de la fuerza al desalojo no se encontró diferencia estadísticamente significativa en los tres grupos. Respecto al comportamiento y falla adhesiva, se encontró una diferencia significativa p < 0.001, favoreciendo a los grupos 2 y 3, por su adhesión en la porción radicular. El tipo de fractura fue restaurable para los tres grupos. Respecto al tiempo y costo, fueron significativamente menores para el grupo 3. Conclusión: En nuestro estudio no existió diferencia significativa en la fuerza al desalojo en los tres grupos; sin embargo, la hubo en el comportamiento, falla adhesiva, costo y tiempo, favoreciendo mayormente al grupo 3. La técnica de reconstrucción con resina puede ser una técnica predecible, suficientemente resistente, conservadora, rápida y de menor costo

Introduction: The use of fiberglass posts is the current method most used for post-endodontic reconstruction. However, its adhesion remains unpredictable due to the limited control of its cementing technique. Bulkfill resins reveal values of flexural strength similar to dentin and their use in post-endodontic reconstruction could be a viable and conservative alternative. Objective: Compare three post-endodontic reconstruction techniques by measuring their resistance to eviction forces, classifying the type of fracture and adhesive failure, evaluating their cost and time of work. Material and methods: 18 samples are divided into 3 groups: group 1: post plus cement of 1 step, group 2: post plus cement of 3 steps and group 3: post-endodontic reconstruction with bulk-fill resin. Results: In the evaluation of the force to the eviction, no statistically significant difference was found in the 3 groups. Regarding the behavior and adhesive failure, a significant difference was found p < 0.001, favoring groups 2 and 3, due to its adhesion in the root portion. The type of fracture was restorable for the 3 groups. Regarding time and cost, they were significantly lower for group 3. Conclusion: In our study there was no significant difference in the force to the eviction in the three groups, however there was in the behavior, adhesive failure, cost and time, favoring mainly the group 3. The technique of reconstruction with resin can be a predictable technique, Sufficiently resistant, conservative, fast and of lower cost (AU)

Effect of different root dentin pretreatment protocols on the bond strength of fiber posts cemented with core buildup material / Efeito de diferentes protocolos de pré tratamento de dentinas radiculares na força de adesão de pinos de fibra cimentados com material de núcleo de preenchimento

Objective: The purpose of the study was to evaluate the push out bond strength of fiber posts -after cementaion with core build up material and dentin pretreatment using different adhesive protocolsin different root regions. Material and Methods: 28 endodonticaly treated human premolars were divided into 4 groups. The post spaces were treated with 1 of 4 different dentin bonding protocols: total etch light cured adhesive, solobond m; total etch dual cured adhesive, Excite f DSC; self-etching light cured adhesive, single bond universal; or selfetching dual cured adhesive, futura bond dc. Fiber posts, were luted with dual cured core material. The roots were cut into 2-mm-thick sections, in cervical, middle, and apical regions. Push-out tests were performed with a universal testing machine, and bond strength values (MPa) were calculated. Data were analyzed with 1- and 2-way analysis of variance and Tukey multiple comparison tests (a=.05). Failure modes were examined under stereo microscope. Results: The highest mean bond strength values were obtained for self-etch dual cured adhesive, (9.69 MPa). The Total etch light cured adhesive (2.81 MPa) showed the lowest bond strength. Self-etch light-polymerized and total etch dual-polymerized adhesives provided similar bond strengths (5.37, 5.72 respectively). The regional bond strength values were reduced significantly in apical post space (P<0.01). The most predominant failure type was mixed failure followed by adhesive failure. Conclusion: Dentin pretreatment using self-etch dual cured adhesives prior to fiber posts cementation offers a high bond strength. While using total-etch light cured adhesives is not recommended due to the low bonding quality.(AU)

Objetivo: O objetivo do estudo foi avaliar a força de adesão dos pinos de fibra após o cimentação com material de núcleo e o pré-tratamento da dentina utilizando diferentes protocolos adesivos em diferentes regiões radiculares. Material e Métodos: 28 pré-molares humanos tratados endodonticamente foram divididos em 4 grupos. Os condutos foram tratados com 1 de 4 diferentes protocolos de união à dentina: adesivo fotopolimerizável total, solobond m; adesivo de polimerização dual de condicionamento total, Excite f DSC; adesivo fotopolimerizável autocondicionante, Single Bond universal; ou adesivo de dupla curado autocondicionante, futura bond dc. Núcleos de fibra, foram cimentados com material resinoso e polimerizados. As raízes foram cortadas em seções de 2 mm de espessura, nas regiões cervical, média e apical. Testes de push-out foram realizados com uma máquina de testes universal, e os valores de resistência de união (MPa) foram calculados. Os dados foram analisados com análise de variância de 1 e 2 fatores e testes de comparação múltipla de Tukey (a = 0,05). Modos de falha foram examinados sob estéreo-microscópio. Resultados: Os valores médios mais elevados de resistência adesiva foram obtidos para o adesivo dual autocondicionante (9,69 MPa). O adesivo fotopolimerizável Total etch (2,81 MPa) apresentou a menor resistência de união. Os adesivos autocondicionantes fotopolimerizáveis e os de condicionamento tal duais, proporcionaram forças de adesão semelhantes (5,37, 5,72, respectivamente). Os valores de força de união regional foram significativamente reduzidos na região apical (P<0,01). O tipo de falha mais predominante foi falha mista seguida de falha adesiva. Conclusão: O pré-tratamento com dentina utilizando adesivos duais autocondicionantes antes da cimentação dos pinos de fibra oferece uma alta resistência de união. Enquanto que os adesivos de condicionamento total fotopolimerizáveis não sforam recomendados devido à baixa qualidade da adesão proporcionada. (AU)

Evaluation of the effect of chlorhexidine and sodium hypochlorite in adhesive cementation of fiber posts - in vitro study / Avaliação do efeito da clorexidina e do hipoclorito de sódio na cimentação adesiva de pinos - estudo in vitro

Abstract Introduction The attachment of fiberglass posts is achieved through an adhesive process. Failures in adhesion may occur due to the hydrolytic degradation of the adhesives, or to the degradation of the collagen fibres of the hybrid layer by intrinsic enzymes. Objective To evaluate the effect of chlorhexidine and sodium hypochlorite treatment on bond strength to dentin. Material and method Thirty bovine roots were randomly distributed into 3 groups (n=10): a) Control, b) 2% Chlorhexidine, and c) 5% Sodium Hypochlorite. Next, RelyX® ARC resin cement was used to cement the post. Each specimen resulted in samples from the three root thirds that were submitted to the pushout test (MPa) at 24 hours and 12 months. Bond strength values were analysed using the Kolmogorov-Smirnov, 3-way ANOVA and Tukey tests. The fracture mode of the pin was also analysed using stereomicroscopy. Result There were no significant differences between treatments at the immediate time (p=0.0644) or in the interaction of factors (p=0.1935). After one year, the experimental groups showed no significant differences in bond strength in relation to the control group, with the exception of the cervical third of the chlorohexidine group in which there was a significant loss of adhesion. As for the fracture mode, there was a predominance of the mixed type in all groups and thirds. Conclusion The use of chlorhexidine or hypochlorite provides neither benefits nor losses in the adhesive bond strength of fiberglass posts. However, there is an influence of the root thirds, with the worst bond strength in the apical third.

Resumo Introdução A fixação de pinos de fibra de vidro é realizada através de um processo adesivo. Falhas podem ocorrer na adesão devido à degradação hidrolítica dos adesivos, ou pela degradação das fibras colágenas da camada híbrida por enzimas intrínsecas. Objetivo Avaliar o efeito do tratamento com clorexidina e hipoclorito de sódio sobre a resistência de união adesiva à dentina. Material e método Trinta raízes bovinas foram distribuídas aleatoriamente em 3 grupos (n=10): a) Controle, b) Clorexidina 2% e c) Hipoclorito de Sódio 5%. Após, para a cimentação do pino radicular, utilizou-se o cimento resinoso RelyX® ARC. Cada espécime resultou corpos-de-prova dos três terços radiculares, os quais foram submetidos ao teste de pushout (MPa) nos períodos de 24 horas e 12 meses. Valores de resistência de união foram analisados pelos testes de Kolmogorov-Smirnov, ANOVA (three-way) e de Tukey. Analisou-se ainda o modo de fratura do pino, através de estereomicroscopia. Resultado Não houve diferenças significativas entre tratamento no tempo imediato (p=0,0644) ou na interação dos fatores (p=0,1935). Após um ano, os grupos experimentais não promoveram diferença significante na resistência de união em relação ao controle, com exceção do terço cervical do grupo clorexidina, onde houve uma perda significativa de adesão. Quanto ao modo de fratura, houve predominância do tipo mista em todos os grupos e terços. Conclusão O uso de clorexidina ou hipoclorito não promove benefícios ou prejuízos na resistência de união adesiva de pinos de fibra, mas há influência dos terços radiculares, sendo a pior resistência de união no terço apical.

Challenges in luting fibre posts: Adhesion to the post and to the dentine.

OBJECTIVE: To investigate the relationship between physicochemical interactions of resin luting cements with dentine and retention of fibre posts in root canals. METHODS: Retention of fibre posts (RelyX Fiber Post) was assessed by the pull-out method. The diffusion zone of the cements and their chemical interaction with dentine were estimated by micro-Raman spectroscopy. Resin luting cements employing etch-and-rinse (Rely X Ultimate and Variolink II), self-etch (Rely X Ultimate and Panavia F2.0), or self-adhesive (RelyX Unicem 2) modes were investigated. Data were analyzed by analysis of variance followed by Tukey HSD tests. RESULTS: The retention of the fibre posts decreased in the following order: RelyX Ultimate, etch-and-rinse mode>RelyX Unicem 2≥RelyX Ultimate, self-etch mode≥Panavia F2.0≥Variolink II (p<0.05). One of the etch-and-rinse mode cements presented the deepest diffusion zone, while the other, along with the self-adhesive cement, produced the shallowest zone. Cements used in the self-etch mode showed intermediary diffusion into dentine (p<0.05). All resin luting cements showed some degree of chemical interaction with dentine, the highest recorded for RelyX Ultimate used in the etch-and-rinse mode and the lowest for Panavia F2.0 (p<0.05). The retention of fibre posts in the root canal could be attributed neither to the mode of interaction of the luting cements with dentine nor to their ability to diffuse into dentine. SIGNIFICANCE: Chemical interaction between the resin luting cement and the dentine paired with adequate post pretreatment contribute positively to the retention of fibre posts.

Estabilizador Endodóntico en Fractura Complicada de Raíz en visita única / Endodontic Stabilizer in Complicated Root Fracture in a single visit

Introducción: La fractura complicada de raíz del tercio medio es una entidad compleja de pronóstico mayormente desfavorable y curso sintomático, donde el éxito clínico en no pocas oportunidades se convierte en una utopía, dado que la estabilidad en el afrontamiento de los bordes libres de los fragmentos fracturados es difícil de lograr. En este sentido el estabilizador edodóntico busca garantizar un anclaje bilateral satisfactorio, que posibilite unificar en una consulta los tiempos operatorios necesarios para un tratamiento exitoso. Objetivo: Describir la factibilidad del uso de un estabilizador endodóntico en el manejo de una fractura complicada de raíz del tercio medio en una visita. Presentación del caso: Paciente de 60 años, femenina que acude a consulta tras sufrir traumatismo dentoalveolar consistente con fractura complicada de raíz del tercio medio en 21; a los rayos X se observa ligero ensanchamiento periodontal y bordes discontinuos. Se realiza tratamiento edodóntico radical mediante la aplicación de un estabilizador intraconducto en la reducción de la fractura. Conclusiones: El uso de un estabilizador endodóntico en el manejo de una fractura complicada de raíz del tercio medio realizado en una sola visita es una alternativa factible de realizar en el tratamiento mediato e inmediato, ya que supone una rápida recuperación de las funciones buco-dentales del paciente(AU)

Introduction:The complicated fracture of the medium third of the root is a complex entity, particularly with an unfavorable prognosis and a symptomatic course in which the clinical success becomes a utopia in not just a few opportunities because the stability by confrontation of the free edges of the fractured fragments is difficult to achieve. In this respect, the endodontic stabilizer is used to guarantee a satisfactory bilateral anchorage that gives the possibility to unify, in a single visit, the necessary operation times for a successful treatment. Objective: To describe the feasibility of the use of an endodontic stabilizer in the management of a complicated fracture of the medium third of the root in a single visit. Case presentation: Female 60-year-old patient who comes to the consulting room after suffering from a consistent dentoalveolar trauma with a complicated fracture of the medium third of the root in tooth no.21; radiograph reveals a slight periodontal widening, and discontinuous edges. Radical endodontic treatment is performed with the placement of an intraductal stabilizer in the reduction of the fracture. Conclusions: The use of an endodontic stabilizer in the management of a complicated fracture of the medium third of the root in a single visit to the dentist is a feasible alternative in the mediate and immediate treatment seeing that it supposes a fast recovery of the bucco-dental functions of the patient(AU)

La mujer cubana: evolución de derechos y barreras para asumir puestos de dirección / Cuban women: evolution of rights and barriers to occupy direction posts

Los derechos de las mujeres cubanas a través de la historia han ido evolucionando como resultado de una incansable lucha. Se realiza una revisión de esta problemática para valorar objetivamente dicha evolución y las barreras que aún existen para que las féminas ocupen cargos de dirección. Se establecen diferentes etapas para el análisis. Se precisaron los momentos de inicio de su derecho al voto, a la igualdad ante el matrimonio y al reclamo del divorcio, comprobándose que estos derechos conquistados por ellas fueron el fruto de grandes luchas por sus reivindicaciones políticas, sociales y culturales. Se expone que existen aún numerosos aspectos que constituyen barreras a la ocupación de cargos de dirección por parte de la mujer, entre ellos los conflictos entre lo laboral y lo doméstico, la necesidad de viajes y traslados al centro laboral diariamente, las responsabilidades familiares, los horarios excesivos y la poca flexibilidad en los mismos, así como el poco tiempo para dedicar a las actividades sociales y recreativas y al cuidado personal (AU).

The rights of Cuban women have evolved through the history as a result of an indefatigable fight. A review of this problem was carried out to objectively appraise that evolution and the barriers still existing for women to occupy managerial positions. Several stages are established to perform the analysis. It was confirmed the date women were given the right to vote, the equality of rights in the marriage and the right of asking for the divorce, stating that these rights conquered by them were the result of a long struggle for their political, social and cultural demands. It is exposed that there are still several aspects arising as barriers against women occupying direction posts, among them the conflicts between work tasks and house tasks, trips for working reasons, daily displacement to work, the excessive hours and the little flexibility in them, and also the few time for social and leisure time activities, and for personal care (AU).