Effect of Gutta-percha Solvents on the Bond Strength of Sealers to Intraradicular Dentin: A Systematic Review

Introduction: The aim of our systematic review was to assess the impact of gutta-percha solvents on the bond strength of endodontic sealers to intraradicular dentin using the push-out bond test. Methods and Materials: The literature was searched in databases (PubMed, Web of Science and Scopus) up to September 2020, using the following search terms: (bond strength AND solvent* AND sealer* AND (tooth root OR dentin OR retreatment OR root canal). No date limits were implemented, and English languages were included. The question research was constructed based on the PICO (Population, Intervention, Comparison, and Outcome) strategy: “Does gutta-percha solvents effect the bond strength of sealers to intraradicular dentin?”. The studies were analyzed by two reviewers and were included if they utilized extracted permanent human teeth with completely formed apices, as well as assessed the influence of gutta-percha solvents on the bond strength of sealers to intraradicular dentin using push-out bond test. Review articles, case reports and studies that included immature, bovine or artificial teeth were excluded. The risk of bias was evaluated based on the Cochrane criteria adopted to in vitro studies.  Results: Thirty-two papers were analyzed, seven accomplished the eligibility criteria and were selected for our systematic review. The global risk of bias was high. Due to variations in the methodological variables, a meta-analysis could not be performed. Conclusion: Our systematic review highlighted the adverse effect of chloroform, which decreased the bond strength of different sealers, and the generally higher bond strength of epoxy resin-based sealers, detected with the push-out bond test. We recommend the standardization of methods in future studies to obtain a more definitive conclusion about the influence of solvents on the bond strength of sealers to intraradicular dentin

Avaliação da qualidade de tratamentos endodônticos realizados por estudantes de Medicina Dentária

Objectives: To assess radiographically the technical quality of root fillings placed by undergraduate students at the Faculty of Dental Medicine of the University of Porto. Methods: The records of 318 patients were assessed, of which 225 radiographs of root canal fillings in single-rooted teeth were selected. The radiographs were examined using the VixWin Platinum v1.1 Imaging Software (Gendex, USA). The quality of root canal filling was graded as "acceptable" when both length and density were adequate. Procedural errors were registered. Chi-square tests were used for statistical analysis, considering a 0.05 significance level. Results: Root canal fillings were considered acceptable in 53.3% of the cases. There was a greater percentage of adequate density (70.7%) than adequate length (64%). There was a statistically significant association between the quality of the filling and the type of tooth, with maxillary anterior teeth presenting higher quality (p=0.027). The most common reason for inadequate length was short-filling (33%). There was a statistically significant relationship between the academic year and the density of the fillings (p=0.009). Overall procedural errors occurred in 3.6% of the cases, with the most common being ledge formation and apical transportation. Conclusions: The quality of root canal fillings in single-rooted teeth performed by junior dental students at the University of Porto was considered acceptable in 53.3% of cases.Objetivos: Avaliar radiograficamente a qualidade das obturações de tratamentos endodônticos realizados por estudantes do Mestrado Integrado da Faculdade de Medicina Dentária da Universidade do Porto. Métodos: Foram avaliados os registos de 318 pacientes, dos quais foram selecionadas 225 radiografias periapicais de dentes monorradiculares. As radiografias foram examinadas utilizando o software de imagem VixWin Platinum v1.1 (Gendex, EUA). A qualidade do tratamento endodôntico foi classificada como "aceitável" quando o comprimento e a densidade estavam adequados. Os erros iatrogénicos foram registados. O teste qui-quadrado foi utilizado para análise estatística, considerando um nível de significância de 0,05. Resultados: O tratamento endodôntico foi considerado aceitável em 53,3% dos casos. Houve uma maior percentagem de densidade adequada (70,7%) do que comprimento adequado (64%). Verificou-se uma associação estatisticamente significativa entre a qualidade da obturação e o tipo de dente, sendo os dentes anteriores superiores a apresentar maior qualidade (p = 0,027). A razão mais comum para o comprimento inadequado foram as obturações curtas (33%). Verificou-se uma relação estatisticamente significativa entre o ano letivo e a densidade da obturação (p = 0,009). Erros iatrogénicos ocorreram em 3,6% dos casos, sendo os mais comuns a formação de degraus e o transporte apical. Conclusões: A qualidade dos tratamentos endodônticos em dentes monorradiculares realizados por estudantes de Medicina Dentária da Universidade do Porto foi considerada aceitável em 53,3% dos casos.- (undefined

The precision of propex Pixi with different instruments and coronal preflaring procedures

Objective:This study aimed to evaluate the influence of the instrument regarding the apical fit and type of the alloy and coronal preflaring procedures in the accuracy of Propex Pixi.Methods: A total of 40 extracted human single-rooted permanent teeth with apical diameters of 200 mu m were selected. A #10 K-file was inserted in the root canal until its end could be observed by a dental microscope to obtain the actual working length (WL). Electronic measurements were performed using Propex Pixi to the root apex ("0.0"). Different file alloys (stainless steel [SS] and nickel titanium [NiTi]) and sizes (#10, #15, and #20) were used before and after coronal flaring. Statistical analysis was performed by a factorial analysis of variance (P <= 0.05).Results: Results showed that the measurements of electronic length (EL) were closer to the actual working length (WL) after coronal flaring (P<0.05). A significant intraclass correlation was observed between EL and WL. In addition, results showed no significant differences between files with different sizes or alloys.Conclusion: Under the conditions of this study, Propex Pixi demonstrated adequate precision. Its accuracy was enhanced by coronal preflaring procedures regardless of the instrument type used (SS or NiTi) and the apical fit.- (undefined

Complicações que podem surgir durante o Uso do Hipoclorito de Sódio no Tratamento Endodôntico

ResumoA solução de hipoclorito de sódio, em diferentes concentrações, é o irrigante mais utilizado durante o tratamento endodôntico. Embora a sua utilização seja geralmente segura, sequelas graves podem ocorrer quando da sua extrusão para além do apex do canal radicular, afectando os tecidos periapicais.Neste artigo procura-se alertar o Médico Dentista (e outros profissionais de Saúde Oral) para os principais acidentes que podem ocorrer com o uso do hipoclorito de sódio durante o tratamento endodôntico.AbstractSodium hypochlorite is the most common irrigant used in endodontic practice. Usually, the use of sodium hypochlorite is safe, although severe sequelae may occur if this solution is extruded beyond the root apex. This article's aim is to draw the Dentist's attention (and other oral health professionals) to the principal accidents that may occur with the use of sodium hypochlorite during the endodontic treatment

Simulated root canals preparation time, comparing ProTaper Next and WaveOne Gold systems, performed by an undergraduate student

The aim of this study was to compare the WaveOne Gold and ProTaper Next systems regarding the time spent preparing simulated canals performed by an inexperienced student. 0 simulated L-shaped canals were randomly divided into two groups (n = 40) and numbered in order of instrumentation. Canals were instrumented with WaveOne Gold (group 1) and ProTaper Next (group 2) systems. The effective instrumentation time and the number of instrumentation cycles were recorded. All procedures were performed by the same operator. Statistical analysis was obtained by the Mann - Whitney, Kruskal - Wallis test with significance of p<0.05. There were no statistically significant differences regarding the mean instrumentation time between the two instrumentation systems. The instrumentation time decreased over the experimental period, regardless of the technique used. Through a short learning curve, an inexperienced operator can prepare simulated canals in a very predictable time. Time spent was similar in a multi-file instrument system (ProTaper Next) and a single-file system (WaveOne Gold)

First experience of an undergraduate dental student with a reciprocating system in simulated root canals - a pilot study

Rotary instrumentation has been proposed in undergraduate teaching. The aim of this study was to evaluate student’s performance, through the obturation quality and treatment time, in a sequential range of L-simulated root canals. A senior undergraduate dental student sequentially prepared randomly numbered canals from 1 to 40, with the WaveOne Gold glider and primary file, according to the manufacturer instructions. A gutta-percha cone matched with the finishing instrument and epoxy resin-based sealer (AH Plus) was selected for the obturation. Three independent observers evaluated the obturation quality according to both density and length. Active, total instrumentation and obturation times were also measured. Statistical analysis was obtained by Mann–Whitney and Kruskal–Wallis tests with a significance level of p < 0.05. The quality of the obturation was independent of the number of prepared canals with adequate length and density in 87.5% of the prepared canals. Both active and total instrumentation, as well as obturation times, reduced significantly as the number of the prepared canals by the student increased (p < 0.05). The use of WaveOne Gold instrumentation and matched cone obturation by an inexperienced operator provided an adequate obturation quality in most of the curved simulated canals. The working time was significantly reduced through a short learning curve

Candida albicans antimicrobial and antibiofilm activity of novel endodontic solvents

Background: Candida albicans is the most prevalent fungi isolated in endodontic infections. In this study, the ability of C. albicans biofilm to tolerate the novel solvent mixtures methyl ethyl ketone (MEK)/tetrachloroethylene (TCE) and MEK/orange oil (OOil) sequentially to the standard irrigation of sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic (EDTA) was evaluated. Methods: Biofilm cell cultures of C. albicans SC 5314 were treated sequentially with NaOCl and EDTA and exposed to MEK/TCE or MEK/OOil. The effect of the antimicrobial treatment was evaluated using the disk diffusion method for planktonic culture, and the enumeration of colony-forming units (CFUs) and scanning electron microscope (SEM) for biofilm cell culture. Results: C. albicans mature biofilm (24 h) was significantly reduced in biomass and cell viability after solvent mixtures exposure, compared with the previous NaOCl and EDTA treatments. MEK/OOil combination caused a total reduction of biofilm, while with MEK/TCE, there was a 3-log (CFU/cm2) reduction compared with the sequence NaOCl and EDTA, and a 4-log (CFU/cm2) reduction compared with the control. Conclusions: The additional exposure of a preformed 24 h C. albicans biofilm to novel solvent mixtures MEK/TCE and MEK/OOil caused a positive antibiofilm impact, overcoming the performance of the conventional endodontic irrigating protocol.This article was supported by National Funds through FCT-Fundação para a Ciência e a Tecnologia, I.P., within CINTESIS, R&D Unit (reference UIDB/4255/2020). This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and grant ref 2020.05720.BD for Liliana Fernandes; BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Validation of a suggested pre-operative protocol for the prevention of traumatic dental injuries during oroendotracheal intubation: a pilot study

The aim of this study was to develop a protocol for oral pre-operative registration and dental risk assessment by the anaesthesiologist, determining its reliability through the inter-observer agreement between a senior dental student and an internal physician specializing in anaesthesiology. A convenience sample consisting of 35 patients was selected. These were observed during the anaesthesiology consultation, at Hospital de São João, Porto, Portugal. The protocol included a self-administered questionnaire and a brief clinical examination by the two observers. A descriptive analysis (qualitative and quantitative variables) was performed. The Fleiss Kappa index was used to measure the degree of agreement between the two observers. In most of the parameters defined, the agreement presented Kappa index values between 0.6 and 1, corresponding to good and excellent correlation, respectively. The general oral status was considered “poor”, with a great number of missing teeth, namely the upper central and lateral incisors. The proposed pre-anaesthetic protocol can be a reliable tool for the anaesthesiologists, which suggests the relevancy of incorporating interdisciplinary training between future health professionals. Further research is needed to assess its implementation, providing information about the pre-operative oral status, preventing intraoperative damage and potential medicolegal litigation

Effect of sonic agitation of a binary mixture of solvents on filling remnants removal as an alternative to apical enlargement — a micro-CT study

Background: This work aimed to evaluate the efficacy of sonic agitation of a binary mixture of solvents (methyl ethyl ketone/tetrachloroethylene) on filling remnants removal and compare the effects of solvent agitation with the enlargement to the next instrument size. Methods: Twenty-four mandibular incisors were prepared with ProTaper Next (X1, X2) and obturated with the single-cone technique and AH Plus sealer. The teeth were retreated with ProTaper Universal Retreatment and ProTaper Next and divided into two groups (n = 12) according to the final instrument (X3 or X4). All canals were submitted to a supplementary procedure consisting of a mixture of solvents―methyl ethyl ketone/tetrachloroethylene, agitated with EndoActivator. The volume of filling remnants was assessed through micro-computed tomography in the apical 5 mm. Statistical analysis was performed with a significance level of 5%. Results: The supplementary procedure of agitation of the solvent mixture was beneficial in both groups (p p > 0.05). Conclusions: An additional step with a two-solvent solution potentiated by EndoActivator showed to be very effective for the removal of gutta-percha and resinous sealer remnants from apical root canals of mandibular incisors, avoiding further enlargement.This article was supported by National Funds through FCT-Fundacao para a Ciencia e a Tecnologia, I.P., within CINTESIS, R&D Unit (reference UIDB/4255/2020)