Influence of genetic polymorphisms on oral health-related quality of life after root canal treatment

Abstract To evaluate the impact of genetic polymorphisms in interleukins (IL1A rs17561, rs1304037; IL10 rs1800871; IL1RN rs9005), nitric oxide (NOS2 rs2779249, rs2897518) and suppressor of cytokine signaling (SOCS1 rs243327, rs33977706) on oral health-related quality of life (OHRQoL) of patients under-going root canal treatment (RCT). Methods: The sample consisted of 108 participants, presenting single-rooted teeth with asymptomatic periapical periodontitis. The impact of the OHRQoL was recorded using the Oral Health Impact Profile (OHIP-14) before, seven, and 30 days after RCT. Saliva samples were collected as a source of genomic DNA. Genetic polymorphisms were genotyped by Real-Time PCR using the Taqman method. Univariate and Multivariate analyses were used (p<0.05). Results: A significant difference was observed for the polymorphism rs2297518 in the NOS2 gene in functional limitation in the codominant (p=0.037) and recessive (p=0.001) models; in the physical pain (p<0.001 in both models); in psychological discomfort (p<0.001 in both models); in physical disability (p<0.001 in both models) and in psychological disability (p<0.001 in both models). Polymorphisms in the SOCS1 gene, in the recessive model, rs33977706 (p=0.045) and rs243327 (p=0.019), influenced the OHRQoL in the psychological discomfort domain. Conclusions: Polymorphisms in NOS2 and SOCS1 genes influenced the OHRQoL of patients undergoing RCT.

Resumo Avaliar o impacto de polimorfismos genéticos em interleucinas (IL1A rs17561, rs1304037; IL10 rs1800871; IL1RN rs9005), óxido nítrico (NOS2 rs2779249, rs2897518) e supressor da sinalização de citocinas (SOCS1 rs243327, rs33977706) na qualidade de vida relacionada à saúde bucal (QVRSB) de pacientes submetidos a tratamento endodôntico (TE). Métodos: A amostra foi composta por 108 participantes, que apresentavam dentes unirradiculares com lesão periapical assintomática. O impacto da QVRSB foi registrado usando o Oral Health Impact Profile (OHIP-14) antes, sete e 30 dias após o TE. Amostras de saliva foram coletadas como fonte de DNA genômico. Os polimorfismos genéticos foram genotipados por PCR em tempo real usando o método Taqman. Análises univariadas e multivariadas foram utilizadas (p<0,05). Resultados: Observou-se diferença significativa para o polimorfismo rs2297518 no gene NOS2 na limitação funcional nos modelos codominante (p=0,037) e recessivo (p=0,001); na dor física (p<0,001 em ambos os modelos); no desconforto psicológico (p<0,001 em ambos os modelos); na deficiência física (p<0,001 em ambos os modelos) e na deficiência psicológica (p<0,001 em ambos os modelos). Polimorfismos no gene SOCS1, no modelo recessivo, rs33977706 (p=0,045) e rs243327 (p=0,019), influenciaram a QVRSB no domínio desconforto psicológico. Conclusões: Polimorfismos nos genes NOS2 e SOCS1 influenciaram a QVRSB de pacientes submetidos a TE.

Mechanism of action of Bioactive Endodontic Materials

Abstract A continuous search for bioactive materials capable of supporting the replacement of damaged pulp tissue, with effective sealing potential and biocompatibility, has represented the attention of studies over the last decades. This study involves a narrative review of the literature developed by searching representative research in PUBMED/MEDLINE and searches in textbooks associated with the mechanism of action of bioactive materials (calcium hydroxide, mineral trioxide aggregate (MTA), and calcium silicate cements). The reflective analysis of the particularities of the chemical elements of these materials, considering the tissue and antibacterial mechanism of action, allows a better understanding of the characteristics and similarities in their tissue responses. Calcium hydroxide paste remains the antibacterial substance of choice as intracanal dressing for the treatment of root canal system infections. Calcium silicate cements, including MTA, show a favorable biological response with the stimulation of mineralized tissue deposition in sealed areas when in contact with connective tissue. This is due to the similarity between the chemical elements, especially ionic dissociation, the potential stimulation of enzymes in tissues, and the contribution towards an alkaline environment due to the pH of these materials. The behavior of bioactive materials, especially MTA and the new calcium silicate cements in the biological sealing activity, has been shown to be effective. Contemporary endodontics has access to bioactive materials with similar properties, which can stimulate a biological seal in lateral and furcation root perforations, root-end fillings and root fillings, pulp capping, pulpotomy, apexification, and regenerative endodontic procedures, in addition to other clinical conditions.

Resumo Uma busca contínua de materiais bioativos com capacidade de substituir o tecido pulpar danificado, com efetiva capacidade de selamento e biocompatibilidade, tem representado a atenção e foco de muitos estudos ao longo das últimas décadas. Este estudo envolve uma revisão narrativa da literatura desenvolvida por meio de pesquisas representativas encontradas no PUBMED/MEDLINE e pesquisas em livros didáticos associadas ao mecanismo de ação de materiais bioativos (hidróxido de cálcio, agregado de trióxido mineral (MTA) e cimentos de silicato de cálcio). A presente análise reflexiva das particularidades dos elementos químicos destes materiais bioativos, considerando o mecanismo de ação tecidual e antibacteriano, possibilita um melhor entendimento das características e similaridades no comportamento tecidual. A pasta de hidróxido de cálcio continua sendo a substância antibacteriana de escolha como medicação intracanal para o tratamento das infecções do sistema de canais radiculares. Este fato se deve a disponibilidade química de íons cálcio e hidroxila do hidróxido de cálcio aos tecidos, e a inibição enzimática bacteriana. Os cimentos de silicato de cálcio, dentre os quais inclui o MTA, apresentam uma resposta biológica favorável ao estímulo à deposição de tecido mineralizado nas áreas seladas e em contato com tecido conjuntivo. Este fato é decorrente da similaridade entre os elementos químicos, em especial devido a dissociação iônica, ao potencial estímulo de enzimas teciduais, e a contribuição com um meio alcalino decorrente do pH destes materiais. O comportamento dos materiais bioativos, em especial o MTA e os novos cimentos de silicato de cálcio na atividade de selamento biológico mostraram efetivos. A endodontia contemporânea atualmente conta com o potencial de materiais bioativos com propriedades análogas capaz de estimular o selamento biológico em perfurações radiculares laterais e de furca, em obturações radiculares, capeamento pulpar, pulpotomia, apicificação e procedimentos endodônticos regenerativos, além de outras condições clínicas.

Influence of bioceramic intracanal medication on the bond strength of bioceramic root canal sealer

Abstract To investigate the influence of the remaining volume of a new intracanal medication based on bioceramic compounds on the bond strength (BS) and formation of an adhesive interface between calcium silicate-based and epoxy resin-based root canal sealers. For this purpose, the specimens were distributed according to the intracanal medication (n = 26): Bio-C Temp (BCT) and Ultracal XS (UXS). The roots were scanned in microCT, and after 7 days, the medication was removed. Then a new scan was performed to evaluate the volume of medication remaining. Subsequently, 40 specimens were redistributed into 2 subgroups (n = 10) and filled according to the sealer used: AH Plus (AHP) and Bio-C Sealer (BCS), to assess the bond strength by using the push-out test, and the adhesive interface by confocal laser fluorescence microscopy (CLSM) and scanning electron microscopy (SEM). The t test showed a smaller remainder of BCT (1.77 ± 0.86) compared with UXS (10.47 ± 5.78), irrespective of the root third evaluated. The BS showed that teeth with BCT + BCS had higher bond strength values (3.70 ± 1.22) when compared to the other groups: BCT + AHP (2.15 ± 1.07), UXS + BCS (3.18 ± 1.09) and UXS + AHP (2.11 ± 1.02) (p<0.001). The cervical third had higher BS when compared with the middle and apical thirds (p < 0.001), and higher number of adhesive failures. The adhesive interface in SEM and CLSM images showed better adaptation for the association between BCT + BCS. Intracanal medication and silicate-based endodontic sealer appeared to interact chemically by forming a biomineralizing layer, allowing for an increase in the bond strength and forming an adhesive interface between the materials, with no or less gap formation.

Impact of access cavities on root canal preparation, restorative protocol quality, and fracture resistance of teeth

Abstract The survival of endodontically treated teeth depends on the remaining tooth structure. The aim of this study was to evaluate the impact of different access cavities on root canal preparation, restorative protocol, and fracture resistance of endodontically treated teeth. Fifty-six mandibular molars were divided into control (n=8) and experimental (n=16) groups according to access cavity: Traditional, Conservative, and Truss; and redistributed (n=8) according to instrumentation protocols: Reciproc Blue and R-motion. After, teeth were scanned in micro-CT and then filled and redistributed according to composite resin restoration (n=8): Filtek One BulkFill and Filtek Z350. A new micro-CT scan was performed to analyze the restorative material. Then, samples were submitted to fracture resistance testing and the failure pattern was determined. Data were analyzed using paired T-test, ANOVA, Tukey, and chi-square tests (α=0.05). In Truss, R-Motion promoted less transportation in different thirds of root canals. Higher percentages of voids (5.05%) and filling material (11.7%) were observed in Truss. Fracture resistance values were higher for the control group, followed by Truss, Conservative, and Traditional. The predominant failure pattern was type-II. In Truss, reciprocating instruments with smaller taper showed less canal transportation. Also, Truss provided higher values of fracture resistance, although it presented a higher percentage of voids and remaining filling material. Thus, in Truss, reciprocating files with smaller taper showed less canal transportation, and these cavities provided higher values of fracture resistance, although it presented a higher percentage of voids and remaining filling material.

Method to determine the root canal spatial geometry using an algorithm of the e-Vol DX CBCT software

Abstract This study evaluated a method to determine the spatial geometry of root canal preparation (RCP) using navigation dynamics and a specific algorithm from a new CBCT software (e-Vol DX). CBCT scans of 168 root canals of mandibular molars were acquired before and after RCP, using nickel-titanium (NiTi) instruments (ProTaper Next, BioRace, Reciproc Blue, and WaveOne Gold). The spatial geometry of the root canals and the operative risk of disproportional wear of dentinal walls after RCP were evaluated using a new CBCT software. A 3-point scoring system was used after the measuring of cementum/dentin thickness before and after RCP in all root thirds. The root thirds were distributed into three parts of similar sizes, and the scores were categorized at three levels: 1. mild risk (1/3), 2. moderate risk (2/3), 3. severe risk (3/3). These levels were proposed according to the risk of creating disproportionate shapes, thin walls, or perforations. The data were analyzed statistically by Fischer's exact test (α = 5%). There were no significant differences in operative risk among the NiTi engine-driven systems, for the distal or mesial walls of all the root canal thirds (p>0.05). The spatial geometry method to assess operative risk allows clinical planning for a predictable enlargement of the root canal in all root thirds. Based on using a map-reading strategy on root canals in CBCT scans, NiTi engine-driven instruments did not present an increased operative risk during RCPs.

Resumo Este estudo avaliou um método para determinar a geometria espacial do preparo do canal radicular (PCR) usando uma dinâmica de navegação e um algoritmo específico do software e-Vol DX. Imagens de tomografia computadorizada de feixe cônico (TCFC) de 168 molares inferiores foram adquiridas antes e depois do PCR, usando instrumentos de níquel-titânio (NiTi) (ProTaper Next, BioRace, Reciproc Blue e WaveOne Gold). A geometria espacial dos canais radiculares e o risco operatório de desgaste desproporcional das paredes dentinárias após o preparo foram avaliados usando o software de TCFC e-Vol DX. Um sistema de Score de 3 pontos foi usado após a mensuração da espessura cemento/dentina antes e depois do PCR, em toda extensão dos canais radiculares. Os terços radiculares foram distribuídos em três partes de tamanhos semelhantes, e os Scores foram categorizados em três níveis: 1. risco leve (1/3), 2. risco moderado (2/3), 3. risco severo (3/3). Esses níveis foram propostos de acordo com o risco de criar formas desproporcionais, paredes finas ou perfurações radiculares. Os dados foram analisados estatisticamente pelo teste exato de Fischer ((=5%). Não houve diferenças significativas no risco operatório entre os sistemas de NiTi acionados a motor, para as paredes distal ou mesial em todos os terços do canal radicular (p>0,05). O método de geometria espacial para avaliar o risco operatório permite o planejamento clínico para um alargamento previsível do canal radicular em todos os terços radiculares. Com base no uso de uma estratégia de navegação dinâmica de canais radiculares de molares inferiores analisados em imagens de TCFC, os instrumentos de NiTi acionados estudados não apresentaram um aumento do risco operatório durante o preparo dos canais radiculares.

Analysis of the mandibular molars root canals morphology. Study by computed tomography

Abstract This study aimed to analyze the root and root canal morphology of mandibular first and second molars using CBCT images. A total of 2,400 mandibular molars exams were selected from 600 patients aged between 18 and 75 years. The number of roots, number of root canals, and root canal configuration according to the Vertucci classification were verified. Overall, 94.92% of mandibular first molars and 90.17% of mandibular second molars had two separate roots. Among the biradicular molars, the first molars showed a greater incidence of type IV canals in the mesial root and type I in the distal root. In the second molars, the most common canal form was type IV in the mesial root and type I in the distal root. In the triradicular molars, the type IV and type I configurations were the most common in the mesial root of the first molar and second molar, respectively. In both triradicular molars, there was a prevalence of type I canal in the distal and DL roots. Statistical analysis was performed at a significance level of 0.05. The number of roots was correlated with gender (Spearman test), and the canal's configuration with gender and bilaterality (Wilcoxon test). The subpopulation studied has a high incidence of bilateral symmetry and mandibular molars with two roots with two distinct mesial canals and one distal canal. The bilateral configuration is possible to estimate the number of canals, especially in images that are difficult to visualize, such as atresic canals.

Genetic, Cellular and Molecular Aspects involved in Apical Periodontitis

Abstract The development, establishment and repair of apical periodontitis (AP) is dependent of several factors, which include host susceptibility, microbial infection, immune response, quality of root canal treatment and organism's ability to repair. The understanding of genetic contributions to the risk of developing AP and presenting persistent AP has been extensively explored in modern Endodontics. Thus, this article aims to provide a review of the literature regarding the biochemical mediators involved in immune response signaling, osteoclastogenesis and bone neoformation, as the genetic components involved in the development and repair of AP. A narrative review of the literature was performed through a PUBMED/MEDLINE search and a hand search of the major AP textbooks. The knowledge regarding the cells, receptors and molecules involved in the host's immune-inflammatory response during the progression of AP added to the knowledge of bone biology allows the identification of factors inherent to the host that can interfere both in the progression and in the repair of these lesions. The main outcomes of studies evaluated in the review that investigated the correlation between genetic polymorphisms and AP in the last five years, demonstrate that genetic factors of the individual are involved in the success of root canal treatment. The discussion of this review gives subsides that may help to glimpse the development of new therapies based on the identification of therapeutic targets and the development of materials and techniques aimed at acting at the molecular level for clinical, radiographic and histological success of root canal treatment.

Resumo O desenvolvimento, estabelecimento e reparo da periodontite apical (PA) depende de vários fatores, que incluem a susceptibilidade do hospedeiro, infecção microbiana, resposta imune, bem como a qualidade do tratamento do canal radicular e a capacidade de reparo do organismo. A compreensão das contribuições genéticas para o risco de desenvolver a PA e apresentar PA persistente tem sido extensivamente explorada na Endodontia moderna. Assim, este manuscrito pretende fornecer uma revisão da literatura em relação aos mediadores bioquímicos envolvidos na sinalização da resposta imune, osteoclastogênese e neoformação óssea, bem como os componentes genéticos envolvidos no desenvolvimento e reparo da PA. Uma revisão narrativa da literatura foi realizada através de uma pesquisa nas bases PUBMED/MEDLINE e uma pesquisa manual nos principais livros sobre a PA. O conhecimento sobre as células, receptores e moléculas envolvidas na resposta imuno-inflamatória do hospedeiro durante a progressão da PA somado ao conhecimento da biologia óssea, especialmente o papel dos osteoblastos, osteócitos e osteoclastos no turnover ósseo, permite a identificação de fatores inerentes ao hospedeiro que podem interferir tanto na progressão como no reparo destas lesões. Os principais resultados dos estudos avaliados na revisão que investigaram a correlação entre polimorfismos genéticos e PA, nos últimos cinco anos, demonstram que os fatores genéticos do indivíduo estão envolvidos no sucesso do tratamento do canal radicular. A discussão desta revisão fornece subsídios que podem ajudar a vislumbrar o desenvolvimento de novas terapias baseadas na identificação de alvos terapêuticos e no desenvolvimento de materiais e técnicas destinadas a atuar a nível molecular para o sucesso clínico, radiográfico e histológico do tratamento endodôntico.

Management of periapical lesion with persistent exsudate

Resumo Este relato de caso descreve o tratamento e acompanhamento de um molar inferior em uma jovem de 18 anos com cisto periapical. Assim, torna-se importante saber quais opções devemos tomar diante de uma situação clínica que não podemos resolver pelos métodos convencionais, e quais técnicas e abordagens temos para alcançar o sucesso do tratamento. Este caso mostrou o plano de tratamento e acompanhamento, por meio de imagens de tomografia computadorizada de feixe cônico (TCFC), de um molar inferior previamente tratado com grande abscesso periapical e lesão cística, no qual, a primeira abordagem do plano de tratamento foi fazer o retratamento endodôntico. Durante o preparo químico-mecânico a presença de exsudato purulento intracanal permanente impossibilitou a secagem dos canais, impedindo a obturação do sistema de canais radiculares. Devido a essa situação clínica, foi realizada abordagem cirúrgica com a intenção de reduzir esse exsudato permanente e executar uma técnica de descompressão. Após um ano de acompanhamento, os achados clínicos e radiográficos indicaram processo de reparo.

Abstract This case describes the treatment and follow-up of a mandibular molar in an 18-year-old female with a periapical cyst. Thus, it becomes important to know which options should we take when faced with a clinical situation that we cannot resolve through conventional methods, and which techniques and approaches we have to achieve treatment success. This case showed the treatment plan and follow-up, by the use of CBCT images, from a previously treated mandibular molar with a large periapical abscess and cystic lesion, in which, the first treatment plan approach was to make the endodontic retreatment. During the chemo-mechanical preparation the presence of permanent intracanal purulent exudate made it impossible to dry the canals, impeding obturation of the root canal system. Due to this clinical situation, a surgical approach was performed with the intention of reduce this permanent exudate and to execute a decompression technique. Clinical findings, periapical radiographs and cone beam computed tomographic, indicated almost complete resolution of the radiolucency, after a one-year follow-up.

Subcutaneous tissue reaction and gene expression of inflammatory markers after Biodentine and MTA implantation

Abstract The aim of this study was to evaluate the subcutaneous connective tissue response of isogenic mice exposed to tricalcium silicate (Biodentine) and aggregated mineral trioxide (ProRoot MTA). A total of 120 mice were divided into 4 groups in 3 different experimental periods (7, 21 and 63 days): Biodentine; Pro-Root MTA; zinc oxide-eugenol and; Negative control - Sham. After the experimental periods microscopic descriptive, semi-quantitative and quantitative analysis of the inflammatory process were analyzed on H&E sections and evaluation of the gene expression of Il10, Infg, Il6, Il1r1 and Tnf (qRT-PCR) were performed. The data obtained were analyzed using the chi-square test and two-way analysis of variance (ANOVA) followed by the Bonferroni post-test (5% significance level). Results: In the microscopic analysis, a slight inflammatory infiltrate was observed, with a predominance of sparse macrophages and polymorphonuclear cells, slight tissue fibrosis, regular fibrous capsule and with dystrophic calcifications, in all groups that received the materials (Biodentine and Pro-Root MTA). In parallel, all materials modulated the gene expression of the different cytokines and receptors evaluated. Conclusion: Pro-Root MTA and Biodentine showed a tissue compatibility, mediated inflammation, with increased fibrous tissue and production of pro- and anti-inflammatory cytokines.

Resumo Objetivo: Avaliar a resposta do tecido conjuntivo subcutâneo de camundongos isogênicos expostos à Biodentine™ e ao Trióxido Mineral Agregado (MTA). Métodos: Um total de 120 camundongos foram divididos em 4 grupos e 3 períodos experimentais diferentes (7, 21 e 63 dias): Biodentine™ (Septodont, Saint Maur des Fosses, França); Pro-Root MTA (Dentsplay, Tulsa, EUA); óxido de zinco eugenol (Biodinâmica Química e Farmacêutica LTDA., Ibiporã, PR - Brasil); e controle negativo - Sham. Após os períodos experimentais, análises microscópicas descritivas, semiquantitativas e quantitativas do processo inflamatório foram analisadas nos cortes de H&E e ainda, foi realizada a avaliação da expressão gênica de Il10, Infg, Il6, Il1r1 e Tnf (qRT-PCR). Os dados obtidos foram analisados por meio do teste do qui-quadrado e da análise de variância (ANOVA) two-way, seguido do pós-teste de Bonferroni (nível de significância de 5%). Resultados: Na análise microscópica observou-se discreto infiltrado inflamatório, com predomínio de macrófagos esparsos e polimorfonucleares, leve fibrose tecidual, cápsula fibrosa regular e com calcificações distróficas, em todos os grupos que receberam os materiais (Biodentine ™ e Pro-Root MTA). Paralelamente, todos os materiais modulam a expressão gênica das diferentes citocinas e receptores avaliados. Conclusão: Pro-Root MTA e Biodentine™ mostraram compatibilidade tecidual, inflamação mediada, com aumento do tecido fibroso e produção de citocinas pró- e antiinflamatórias.

Impact of COVID-19 on gender gap in dental publications: a retrospective cohort with three Brazilian journals

Abstract This was a retrospective cohort study to investigate the impact of COVID-19 pandemic on the gender gap in articles submitted to three international dental journals based in Brazil. All submissions performed to Brazilian Dental Journal, Brazilian Oral Research, and Journal of Applied Oral Science before (2019) and during the pandemic (2020) were assessed. Gender of the first, last, and corresponding authors were collected. Other variables collected were journal, continent studied by authors and stage of their careers (classified according to authors' highest degree), and final decision reached in the article. Absolute and relative frequencies with 95% confidence intervals, Pearson's Chi-square tests, and Fisher's Exact test were used (α = 0.05). In total, 4,726 unique submissions were analyzed. A higher proportion of early-career authors was observed during the pandemic (44.8% to 49.3%, p = 0.021). Most articles were rejected but without association with gender. Increased proportion of male first authors from before to during the pandemic was observed (39% to 42.1%, p = 0.034). Drop in the proportion of articles with women as first authors was observed for researchers in their early- (65.9% to 58.8%, p = 0.02) and mid-career stages (63% to 55.8%, p = 0.014). Reduction in women as first authors was observed during the pandemic in South and Central Americas (66.7% to 61.5%, p = 0.010), and when the last author was a female, or the corresponding author was a male. In conclusion, a disproportionate impact on female dental researchers in submitting articles in the period from before to during the pandemic was observed when considering first authorship, suggesting that the COVID-19 may have increased the gender inequality in dental science.

Heat-treated NiTi instruments and final irrigation protocols for biomechanical preparation of flattened canals

Abstract This study evaluate shaping ability of heat-treated NiTi-alloy instruments associated with different final irrigation protocols in flattened root canals. Thirty human mandibular incisors with flattened root canals were divided into 5 groups (n = 10): (XP) Original Protocol XP-endo Shaper; (XP-WT) Original Protocol XP-endo Shaper with working time variation; (XP-K) XP-endo Shaper with kinematics variation; (XP-WTK) XP-endo Shaper with kinematics and working time variations; (Hyflex) Hyflex CM. For the variation in working time protocols the same sample of the XP-endo Shaper groups with and without kinematic variation were used. To evaluate final irrigation protocols, groups 1, 3 and 5 were submitted to 3 protocols: (NI) No irrigation (n = 2); (CI) conventional irrigation (n = 4), and (EndoVac) irrigation (n = 4). The samples were scanned by microcomputed tomography and prepared for scanning electron microscopy evaluation. Quantitative data were evaluated using the parametric ANOVA test, with statistical significance level set at 5%, and qualitative data obtained were compared to establish the agreement between examiners through the Kappa test. It was observed that in the analysis of XP-endo Shaper protocols, the additional working time did not cause difference in any of parameters evaluated (p > 0.05) in relation to time recommended by manufacturer. Compared to Hyflex, XP-K showed highest mean volume increase (p < 0.05) and lowest percentage of untouched walls (p < 0.05). In the qualitative evaluation, final irrigation protocol with EndoVac provided the best cleaning results when associated with XP-K and with Hyflex. Thus, supplementary techniques are effective tools to enhance cleaning and to promote higher touch of walls during root canal preparation.

Influence of anatomical features in the endodontic treatment planning of maxillary anterior teeth

Abstract This study evaluate the maxillary anterior teeth anatomy by micro-computed tomography (μCT), about relevant characteristic for endodontic treatment planning. Fifty maxillary central incisors (MCI), lateral incisors (MLI) and maxillary canines (MC) were scanned using a μCT device. Two and three-dimensional parameters at 1 to 5mm distance to the apical foramen, external anatomic characteristics of the teeth and qualitative analysis of the internal anatomy was performed. The roundness and form factor values revealed a circular canal in the apical third in the MCI and MC, whereas MLI showed flattening in the apical third. The linear regression test indicated a progressive increase in the major/minor diameters in the five mm assessed (p < 0.001). The 3D analysis revealed the greatest volume and surface area in MC. The SMI showed a cylindrical geometry of root canals. All teeth presented Vertucci's type I root canal configuration. A mild curvature was prevalent in the MCI (45%) and a moderate one in the MLI (50%) and MC (50%). Palatal shoulder volume was smaller in the MLI (11.46 ± 3.09) than in the MCI (14.15 ± 3.85) and MC (13.95 ± 2.55). The most common exit of main apical foramen was in a central (22%), distolingual (30%) and mesiobuccal position (28%) for MCI, MLI and MC, respectively. Radicular grooves were observed in 2% of MCI and 4% of MLI. Two and three-dimensional data obtained by μCT allowed to observe morphological characteristics of internal/external anatomy of the maxillary anterior teeth. These characteristics may affect the endodontic treatment planning.

Method to Identify Accessory Root Canals using a New CBCT Software

Abstract This study describes a methodology to identify accessory root canals using the e-Vol DX software in CBCT scans. Accessory root canals are strategic shelters for microorganisms present in root canal infections. The identification of these small canals in periapical radiographic exams has limitations, besides being markedly limited accessibility to the action of endodontic instruments and to the antimicrobial agents. A significant number of accessory canals have sufficient diameters to be visible on cone-beam computed tomography (CBCT) images of high spatial resolution. Therefore, it may go unnoticed or even confused when there is no specific training for this type of diagnosis. The methodology consists in establishing thin slices (0.1mm or smaller) obtained from coronal, sagittal and axial slices. The method consists of the following steps: during navigation along the long axis of a root canal when finding a possible hypodense line of main root canal in a tomographic section (axial, sagittal or coronal), the navigation software lines of the multiplanar reconstruction (MPR) must be adjusted so that they are parallel and perpendicular to the hypodense line (parallax correction). Then, after judiciously adjusted, the accessory canal image will invariably appear as a line on one of the MPR tomographic slices, another line on another slice, and a dot on the third slice. The three sections of the MPR present images with the "line-line-dot" sequence. In this way, it is possible to identify an accessory root canal and also visualize it in volumetric reconstruction in a specific filter. The application of this method is easy to employed and may benefit the diagnosis when you want to visualize accessory root canals and distinguish it from root fracture line.

Resumo Este estudo descreve um método para identificar canais radiculares acessórios usando o software e-Vol DX em imagens de TCFC. Os canais radiculares acessórios constituem abrigos estratégicos aos micro-organismos presentes nas infecções endodônticas. A identificação destes pequenos canais em exames radiográficos periapicais apresenta limitações, além de apresentar baixa acessibilidade natural a ação dos instrumentos endodônticos e dos agentes antimicrobianos. Os canais acessórios apresentam diâmetros suficientes para ficarem visíveis em imagens de tomografia computadorizada de feixe cônico (TCFC) de alta resolução espacial. Porém, podem passar despercebidos ou até confundidos quando não ocorrer treinamento específico para este tipo de diagnóstico. A metodologia consiste em estabelecer finos slices (0,1 mm ou menor) obtidos a partir de cortes coronal, sagital e axial. O método consiste nos seguintes passos: ao encontrar uma linha hipodensa de um canal radicular principal em um corte tomográfico (axial, sagital ou coronal) deve-se ajustar as linhas de navegação da reconstrução multiplanar (MPR) para que fiquem paralelas ao canal principal e perpendiculares a esta linha hipodensa (correção de paralaxe). A seguir, depois de criterioso ajuste da imagem em busca do canal acessório, aparece invariavelmente como uma linha em um dos cortes tomográficos da MPR, outra linha em outro corte e um ponto no terceiro corte. Os três cortes da MPR apresentam imagens com a sequência linha-linha-ponto. Desta maneira, pode-se identificar um canal acessório e visualizá-lo em reconstrução volumétrica em filtro específico. Esta metodologia é fácil de ser aplicada e pode beneficiar o diagnóstico quando se deseja identificar canais radiculares acessórios e distingui-lo de linha de fratura radicular.

Cytotoxicity and inflammatory mediators release by macrophages exposed to real seal xt and sealapex xpress

Abstract This study evaluated the cytotoxicity of Sealapex Xpress and Real Seal XT and their effect on macrophage activation. J774.1 macrophages were incubated with Sealapex Xpress and Seal Real XT (0.1, 1.0, and 10 mg/mL) for 24 and 48 h. Cell viability was assessed by the MTT assay and macrophage activation was measured by pro- and anti-inflammatory cytokine production using ELISA. Data were analyzed using one-way ANOVA and Tukey's post-test (a=0.05). Cell viability was not affected with 0.1 or 1.0 mg/mL of extracts of Sealapex Xpress and Real Seal XT at 24 and 48 h (p>0.05), but was significantly lower when cells were exposed to 10 mg/mL of both sealers (p<0.05). Sealapex Xpress inhibited the production of TNF-a, whereas Real Seal XT induced TNF-a secretion at 24 h (p<0.05). IL-6 production was induced by Real Seal XT, but not by Sealapex Xpress (p<0.05). Real Seal XT and Sealapex Xpress induced the secretion of anti-inflammatory IL-10. IL-4 was not detected in any group. In conclusion, both sealers had low toxicity but differentially activated macrophages. Macrophage activation by Sealapex Xpress was characterized by inhibition of TNF-a and induction of IL-10, whereas Real Seal XT induced IL-6 solely.

Resumo O objetivo deste estudo foi avaliar in vitro a citotoxicidade dos cimentos endodônticos Sealapex Xpress e Real Seal XT pelo ensaio de MTT e a ativação de macrófagos J774.1. Os cimentos endodônticos Sealapex Xpress e Real Seal XT foram pesados e os extratos foram obtidos a partir da diluição em meio de cultura DMEM por 48 horas (10mg/mL, 1mg/m, e 0,1 mg/mL). A viabilidade celular foi avaliada pelo ensaio MTT e a produção de citocinas (TNF-a, IL-6 e IL-10) foi investigada pelo ensaio imunoenzimático (ELISA) em células de linhagem (macrofagos J774.1). Os dados obtidos foram analisados utilizando-se análise de variância de uma via e pós-teste de Tukey (a=0,05). A viabilidade celular após 24 ou 48 horas não foi afetada nas concentrações de 0,1 ou 1 mg/mL dos dois cimentos estudados (p>0,05). Por outro lado, na concentração 10 mg/mL, a viabilidade celular foi significativamente mais baixa (p <0,05). Observou-se que o Sealapex Xpress inibiu a produção de TNF-a, enquanto o Real Seal XT induziu a secreção de TNF-a às 24 h (p<0,05). A produção de IL-6 foi induzida pelo Real Seal XT, mas não pelo Sealapex Xpress (p<0,05). A secreção da citocina anti-inflamatória IL-10 foi induzida tanto pelo Real Seal XT quanto pelo Sealapex Xpress. IL-4 não foi detectada em nenhum grupo. Em conclusão, os dois cimentos obturadores apresentaram baixa toxicidade, mas ativaram os macrófagos de modo distinto. A ativação pelo Sealapex Xpress foi caracterizada pela inibição do TNF-a e indução da IL-10, enquanto o Real Seal XT induziu somente IL-6.

Micro-CT evaluation of maxillary first molars: interorifice distances and internal anatomy of the mesiobuccal root

Abstract: This study aimed to describe the morphometric relationship of root canal orifices on the pulp floor in the presence/absence of mesiobuccal second canal (MB2) in the maxillary first molars and other aspects of its internal anatomy. Sixty-two maxillary first molars were scanned by micro-CT. The presence of the MB2 canal was verified. The distance between the center points of the MB1, MB2, distobuccal (DB), and palatal (P) canal orifices on the pulp floor were measured (MB1-MB2, MB1-DB, MB2-DB, MB1-P, and DB-P). The MB1-P to DB-P ratio was calculated. The distances between the anatomic apex and the MB1 and MB2 apical foramina were measured. The length of the band-shaped isthmus was also measured. Student's t-test was applied to verify the association between the presence of an MB2 canal, the interorifice distances, and the ratio of the MB1-P to DB-P distance (α = 5%). The MB2 canal was present in 43 roots (69.35%). Statistics showed significant differences when MB2 was present for the largest MB1-P distance (p < 0.05) and higher values for the MB1-P to DB-P ratio (p < 0.05). A band-shaped isthmus was detected in 25.8% of MB roots. The mean distance from the apical foramen to the isthmus floor ranged from 1.74 for MB1 canals to 1.42 for MB2 canals. Canal orifice distances on the pulp floor may predict the presence of MB2 canals. There was a high incidence of isthmus, accessory canals, and apical delta in the critical apical zone in MB roots of maxillary first molars.

Cirurgia do periápice para remoção de lesões granulomatosas: relato de caso / Periapical surgery to remove granulomatous lesion

Periapical granuloma is a histological term that refers to the formation of a mass of granulomatous tissue around the apex of a tooth resulting from inflammation and necrosis of the pulp tissue. It consists of an infiltrate of inflammatory cells such as macrophages, plasmocytes and lymphocytes, as well as fibroblasts, collagen fibers and capillaries. Periapical surgery is an alternative for preserving the tooth in the oral cavity in cases where periapical inflammation is persistent even after treatment of root canals. The objective of this study was to report a clinical case in which the surgical technique was used to remove granulomatous lesions from a patient, female, with a history of recurrent periapical abscess without painful symptomatology in the region of the anterior 11,12 and 13 teeth. The histopathological exam demonstrated the presence of a granulomatous tissue with intense inflammatory infiltrate mixed, permeated with lymphocytes and high number of plasmocytes, confirming the diagnosis of periapical granuloma. The treatment was considered successful since the patient remained asymptomatic and there was incorporation of the inorganic bovine bone graft and initiation of bone neoformation in the periapical region.

Granuloma periapical é um termo histológico que refere-se à formação de uma massa de tecido granulomatoso ao redor do ápice de um dente, decorrente da inflamação e necrose do tecido pulpar. É constituído por um infiltrado de células inflamatórias como macrófagos, plasmócitos e linfócitos, além de fibroblastos, fibras colágenas e capilares. A cirurgia do periápice é uma alternativa para preservação do dente na cavidade bucal nos casos em que a inflamação periapical é persistente mesmo após tratamento dos canais radiculares. O objetivo desse trabalho é relatar um caso clínico no qual a técnica cirúrgica do periápice foi utilizada para remoção de lesões granulomatosas de uma paciente, do sexo feminino, com histórico de abscesso periapical recidivante sem sintomatologia dolorosa na região dos dentes anteriores superiores 11, 12 e 13. O exame histopatológico demonstrou a presença de um tecido granulomatoso com intenso infiltrado inflamatório misto, permeado com linfócitos e elevado número de plasmócitos, confirmando o diagnóstico de granuloma periapical. O tratamento foi considerado exitoso, visto que a paciente se manteve asintomática e houve incorporação do enxerto ósseo bovino inorgânico e início da neoformação óssea na região periapical.

Micro-computed tomographic assessment of the variability and morphological features of root canal system and their ramifications

Abstract Objectives This study assessed the incidence and variability features of root canals system (RCS) and their ramifications according to Pucci & Reig (PR) (1944) and the American Association of Endodontists (AAE) (2017) by micro-computed tomography (μCT). Methodology 500 representative extracted human teeth of each tooth group (n=50) (maxillary/mandibular central and lateral incisors, canines, first and second premolars and molars) were scanned by μCT with a resolution of 26.70 μm. The reconstructed cross-sections images and the visualization of the continuous slices in the transversal axis were performed using DataViewer software. RCS were classified according to Pucci & Reig (main canal, collateral canal, lateral canal, secondary canal, accessory canal, intercanal, recurrent canal) and AAE (main canal, accessory canal, lateral canal). The apical deltas were assessed for both classifications. The prevalence of apical deltas was evaluated using the Chi-squared test (p<0.05). Results According to PR, a higher incidence of lateral canals was observed in maxillary canines (10%), central incisors (8%) and first premolars (6%). Using AAE, the highest incidence of lateral canals was observed in the mandibular first premolars (85%), first and second molars (84%), lateral incisors (67%), canines (59%), and in maxillary first premolars (52%). Regarding accessory canals, the PR showed a frequency in 2% of the maxillary lateral incisors and maxillary and mandibular first premolars and 3% of mandibular first and second molars. On the other hand, the AAE showed the highest incidence of accessory canals in 86% of the maxillary first premolars, 71% in mandibular lateral incisors, 69% in mandibular first premolars, 65% in mandibular canines, and 56% in maxillary canines. The PR showed the lowest incidence of apical deltas for all dental groups when compared with AAE (p=0.004). Interestingly, distal canals in maxillary molars showed a significant discrepancy between classifications (p=0.027). Conclusions μCT enabled accurately describing the RC system and related ramifications, adding to the PR and AAE classifications, with some discrepancies reported for maxillary molars. Clinical Relevance This μCT study enabled a thorough description of the variability among root canals and their ramifications, including clinically relevant details on the presence and location of lateral canals and accessories in all human tooth groups, beyond the currently existing classification systems.

Cone-beam and micro-computed tomography for the assessment of root canal morphology: a systematic review

Abstract This study presents an overview of the accuracy of cone beam computed tomography (CBCT) compared with micro-computed tomography (μCT) in the assessment of root canal morphology of extracted human permanent teeth. A database search in PubMed, PubMed Central, Embase, Scopus, Opengrey, Scielo and Virtual Health Library was conducted which compared root canal morphology of extracted human permanent teeth on the accuracy of CBCT with μCT. In accordance with PRISMA statement guidelines, data were extracted on study characteristics, target mediators, sampling and assay techniques and the parameters associated with obtaining the image and ability to identify the root canal morphology. Amongst 2734 records, ten fulfilled the inclusion criteria. Four studies compared the accuracy of CBCT and μCT in the assessment of root canal morphology using Vertucci's classification, with at least one CBCT group or subgroup of each study presented high agreement compared to the μCT. Six studies assessed more detailed root canal morphology, including two articles that found a lack of agreement between these imaging systems. Risk of bias was deemed low in three studies, moderate in four and high in three. CBCT can be as accurate as μCT in the assessment of several morphological features of extracted human permanent teeth; however there are some exceptions related to the more detailed morphological aspects. Voxel size likely influences the ability to detect these features, though the different aspects of exposure setting used in studies components may be confounding factors. CBCT may be considered for the assessment of root canal morphology ex-vivo.

A micro-CT evaluation of the performance of rotary and reciprocating single-file systems in shaping ability of curved root canals

Abstract To compare the shaping ability of different single-file systems in the preparation of mesial curved canals of mandibular molars using micro-CT technology. Fifteen mesial roots of mandibular molars with two independent and curved canals (n = 30) were selected, scanned at a resolution of 26.7 μm anatomically matched, and distributed into three groups (n = 10), according to the preparation system: WaveOne 25.08, Reciproc 25.08, and OneShape 25.06. A final micro-CT scanning was performed, data sets were registered with their respective counterparts, and compared regarding the three-dimensional (volume, surface area, and structure model index - SMI) and two-dimensional (perimeter, area, roundness, major and minor diameters) parameters, as well as, canal transportation, using ANOVA and post hoc Tukey tests (α = 5%). Overall, no difference was observed between groups regarding area, perimeter, volume, surface area, and canal transportation (p > 0.05). Within group, no canal transportation was significantly higherobserved in the apical third (0.10 ± 0.05 mm) compared to coronal (0.08±0.040 mm) and middle (0.07 ± 0.03 mm) thirds (p < 0.05). Structure model index (SMI) was statistically higher after preparation with OneShape instrument (0.36 ± 0.26) compared to other systems (p < 0.05). Within the parameters of this study, similar shaping ability was observed in the preparation of mesial curved root canals of mandibular molars with Reciproc, OneShape and WaveOne systems.

Radiographic and immunohistochemical evaluation of root canal treatment using different irrigation systems

Abstract The aim of this study was to evaluate the radiographic periapical repair and the synthesis of inflammatory mediators after endodontic treatment in a single session, using different irrigation protocols, in teeth with apical periodontitis. Experimental apical periodontitis were induced in dog's teeth randomly assigned into 4 groups: G1 - Irrigation by Negative Apical Pressure (n= 20); G2 - Passive Ultrasonic Irrigation (n= 20), G3 - Positive Pressure Irrigation (n= 20); G4 - apical periodontitis without treatment (n= 20). After 180 days, the animals were euthanized, the tissues removed and submitted to histotechnical processing for immunohistochemical analysis of osteopontin (OPN), tumor necrosis factor-a (TNF-a) and interleukin 1-a (IL-1a). Radiographic analysis was performed using the Periapical Index (PAI), obtained prior to and 180 days following endodontic treatment. Data were analyzed using Wilcoxon signed-rank test, Fisher's Exact test or Kruskal-Wallis test and Dunn's post-test (a = 5%). Radiographically, after endodontic treatment, apical periodontitis persisted in 35% of G1 specimens, 40% of G2 and 40% of G3 (p>0.05), although a PAI reduction was observed (p<0.05). By immunohistochemical evaluation, endodontic treatment resulted in lower synthesis of TNF-a and OPN in periapical region, compared to apical periodontitis without treatment (p<0.05). Production of IL-1 was not modulated by endodontic treatment (p>0.05). Periapical healing was observed in approximately 60% of the cases after endodontic treatment performed in a single session with lower synthesis of TNF-a and OPN in the periapical region, regardless of the irrigation protocol used.

Resumo O objetivo deste estudo foi avaliar o reparo periapical e a síntese de mediadores inflamatórios após tratamento endodôntico em dentes de cães com lesão periapical, em sessão única, utilizando diferentes protocolos de irrigação. Lesões periapicais foram induzidas experimentalmente em dentes de cães e aleatoriamente divididas em 4 grupos: G1 - Irrigação por Pressão Apical Negativa (n = 20); G2 - Irrigação Ultrassônica Passiva (n = 20), G3 - Irrigação por Pressão Positiva (n = 20); G4 - Lesão periapical sem tratamento (n = 20). Após 180 dias, os animais foram eutanasiados, as peças removidas e submetidas ao processamento histotécnico para análise imunohistoquímica para osteopontina (OPN), fator de necrose tumoral-a (TNF-a) e interleucina 1-a (IL-1a). A análise radiográfica do reparo das lesões periapicais foi realizada por meio do Índice Periapical, obtido antes e 180 dias após o tratamento endodôntico. Os resultados obtidos foram submetidos à análise estatística por meio dos testes de sinais de Wilcoxon, Exato de Fisher ou Kruskal-Wallis seguido pelo pós-teste de Dunn (a = 5%). O exame radiográfico após o tratamento endodôntico, mostrou a persistência de áreas radiolúcidas periapicais e descontinuidade da lâmina dura em 35% dos espécimes do G1, 40% do G2 e 40% do G3, embora uma redução no PAI tenha sido observada (p<0,05). Pela análise imuno-histoquímica, o tratamento endodôntico resultou na menor síntese de TNF-a e de OPN na região periapical, comparativamente à lesão periapical sem tratamento (p<0,05). A produção de IL-1a não foi modulada pelo tratamento endodôntico (p>0,05). Reparo da lesão periapical foi observado em cerca de 60% dos casos após tratamento endodôntico realizado em sessão única e menor síntese de TNF-a e de OPN na região periapical, independente do protocolo de irrigação utilizado.