Endodontic guide for the conservative removal of a fiber-reinforced composite resin post.

Prosthetic dentistry involves functional and esthetic restoration. Some situations require the use of fiber-reinforced composite resin posts that help preserve restorations. However, if the initial treatment fails, a new endodontic intervention may be required for fiber-reinforced composite resin post removal. This procedure can be complex and challenging but can be facilitated with guided endodontics. This clinical report describes the use of a prototyped guide created with virtual planning for fiber-reinforced composite resin post removal. The guide improved patient safety, shortened the treatment time, and eliminated the need for a new restoration.

Avaliação da carga microbiana e fúngica de sistemas de canais radiculares infectados e a expressão apical de integrinas, citocinas e quimiocinas nos tecidos / Assessment of the microbial and fungal load of infected root canal systems and the apical expression of integrins, cytokines and chemokines in adjacent perirradicular tissues

Este estudo busca avaliar quantitativamente a expressão do RNA mensageiro (mRNA) das integrinas alfa1, alfa4, alfa 5, alfa L, citocinas e quimiocinas, a partir de células presentes no líquido intersticial periapical adjacente a dentes com infecção do canal radicular. Foram selecionados 22 indivíduos com necessidade de tratamento endodôntico e encaminhados à Faculdade de Odontologia da Universidade Federal de Minas Gerais (Belo Horizonte, MG, Brasil). As amostras foram coletadas em 11 dentes necróticos e portadores de infecções endodônticas e 11 dentes hígidos que necessitavam de tratamento endodôntico por motivos protéticos. Após a cirurgia de acesso e antes dos procedimentos de limpeza e modelagem do sistema de canais radiculares (T0), imediatamente após a limpeza e formatação do sistema de canais radiculares(T1), em 7 (T2) e 14 dias (T3), um cone de papel esterilizado endodôntico # 20 foi inserido no SCR, mantido por 2 min, e posteriormente armazenado a -70°C. Real-Time PCR analisou microbiologicamente essas amostras para ler a expressão gênica do rRNA microbiano 16S e fragmentos da região ITS do gDNA fúngico da espécie Candida. Após os procedimentos de limpeza e formatação do SCR, três cones de papel absorvente esterilizados foram inseridos. Passivamente, a ponta do papel ultrapassou o ápice radicular em 2 mm e permaneceu por 2 minutos. As amostras foram coletadas imediatamente após a limpeza e modelagem do RCS, 7 e 14 dias após a primeira sessão. As pontas de papel tiveram os 4 mm finais cortados, inseridos em Eppendorf e armazenados a - 70°C. Com este procedimento, o RNA foi extraído do líquido intersticial periapical para caracterizar as expressões dos genes ITGA1, ITGA4, ITGA5, ITGAL, IL-1ß, TNF-α, IL-17A, IL-10, IFN-γ, CCL2/MCP-1, CCL5, CXCR4, e 16S usando PCR em tempo real. O DNA genômico (gDNA) foi extraído para se avaliar a abundância de Candida utilizando-se sequências ITS, por PCR em tempo real. Os resultados demonstraram que os níveis de expressão de mRNA do 16S diminuíram após os procedimentos de limpeza e modelagem e que a abundância de Candida foi insipiente na amostra analisada. As citocinas pro- inflamatórias IL-1ß e IL-17 apresentaram níveis de expressão elevados frente a infecção, reduzindo significativamente após os procedimentos de limpeza e formatação. Os níveis de expressão gênica de TNF-α significantemente aumentaram, em ambos os grupos. Não se observou diferença significativa quanto a expressão gênica das citocinas IFN-γ, IL-10, CCL-2 e CCL-5 e das integrinas ITGAL e ITGA5 nos tempos avaliados. A expressão gênica de CXCR4 reduziu significativamente do tempo T1 para o T2, no grupo experimental. As expressões gênicas de ITGA1 e ITGA4, no grupo experimental, reduziram significativamente de maneira tempo dependente. Finalmente, não houve alteração significativa na expressão de marcadores de macrófagos (CD64), enquanto expressão de marcadores de fibroblastos (S100A4) aumentou significativamente no grupo controle. Concluiu-se que a carga microbiana e a abundância de leveduras correlacionam-se positivamente com a expressão de mediadores pró-inflamatórios e que a que terapia endodôntica negativamente impacta a expressão dos mediadores pró-inflamatórios e das integrinas nos tecidos perirradiculares.

This study seeks to quantitatively evaluate the expression of messenger RNA (mRNA) of integrins alpha1, alfa4, alpha 5, alpha L, cytokines, and chemokines, from cells present in the periapical interstitial fluid adjacent to teeth with root canal infection. Twenty-two individuals needing endodontic treatment and referred to the School of Dentistry of the Federal University of Minas Gerais (Belo Horizonte, MG, Brazil) were selected. The samples were collected in 11 necrotic teeth and carriers of endodontic infections and 11 healthy teeth needing endodontic treatment for prosthetic reasons. After access surgery and before root canal system (RCS) cleaning and shaping procedures (T0), immediately after cleaning and shaping the root canal system (T1), in 7 (T2) and 14 days (T3) an endodontic sterilized paper point #20 was inserted into the RCS, maintained for 2 min, and subsequently stored at -70°C. Real-Time PCR microbiologically analyzed these samples to read the gene expression of microbial rRNA 16S and fragments of the ITS region of the Fungus Candida species gDNA. After RCS cleaning and shaping procedures, three sterilized absorbent paper cones were inserted. Passively, the paper point exceeded the root apex by 2 mm and remained for 2 minutes. Samples were collected immediately after RCS cleaning and shaping, 7 and 14 days after the first session. The paper points have the 4 mm of their tip cut, inserted in Eppendorf, and stored at - 70°C. This procedure extracted RNA from the periapical interstitial fluid to characterize the expressions of the genes ITGA1, ITGA4, ITGA5, ITGAL, IL-1ß, TNF- α, IL-17A, IL-10, IFN-γ, CCL2/MCP-1, CCL5, CXCR4, ITS using Real-Time PCR. The results showed that 16S mRNA expression levels decreased after cleaning and modeling procedures and that Candida abundance was incipient in the analyzed sample. Pro-inflammatory cytokines IL-1ß and IL-17 showed high expression levels against infection, significantly reduced after cleaning and formatting procedures. TNF-α gene expression levels significantly increased in both experimental and control groups. No significant difference was observed regarding the gene expression of the cytokines IFN-γ, IL-10, CCL-2, and CCL-5 and the integrins ITGAL and ITGA5. The gene expressions of ITGA1 and ITGA4 in the experimental group were significantly reduced time-dependent. Finally, there was no significant change in their macrophage markers (CD64) expression, while fibroblast markers (S100A4) expression significantly increased in the control group. It was concluded that microbial load and yeast abundance are positively correlated with the expression of pro-inflammatory mediators and that endodontic therapy negatively impacts the expression of pro-inflammatory mediators and integrins in periradicular tissues.

The apical root canal system microbial communities determined by next-generation sequencing.

The aim of this study was to explore the microbial communities of endodontic infections at their apical portion by 16S rRNA Illumina sequencing and delineate the core microbiome of root canal infections and that of their associated clinical symptomatology. Samples were collected from fifteen subjects presenting one tooth with a root canal infection, and their associated symptoms were recorded. Samples were collected from the apical third of roots using a #10 K file and then amplified using multiple displacement amplification and PCR-amplified with universal primers. Amplicons were sequenced (V3-V4 hypervariable region of the 16S rRNA gene) using MiSeq (Illumina, CA). The microbial composition of the samples was determined using QIIME and HOMINGS. Data were analyzed using t tests and ANOVA. A total of 1,038,656 good quality sequences were obtained, and OTUs were assigned to 10 bacterial phyla, led by Bacteroidetes (51.2%) and Firmicutes (27.1%), and 94 genera were represented primarily by Prevotella (17.9%) and Bacteroidaceae G-1 (14.3%). Symptomatic teeth were associated with higher levels of Porphyromonas (p < 0.05) and Prevotella. P. endodontalis and P. oris were present in both cores. The present study demonstrated the complexity of the root canal microbiome and the "common denominators" of root canal infections and identified taxa whose virulence properties should be further explored. The polymicrobial etiology of endodontic infections has long been established. However, few studies have focused on expanding the breadth and depth of coverage of microbiome-infected root canals at their apical portion.

Avaliação da expressão de integrina alfa2, proteína de choque térmico 47, e mediadores pro-inflamatórios e imunorregulatórios em resposta à infecção endodôntica / To examine alpha 2 integrin, molecular mediators, cytokines, and chemokines from cells in periapical interstitial fluid from root canal infections

Objetivo: analisar a expressão de integrina alfa2, mediadores moleculares, citocinas e quiocinas, a partir de células presentes no líquido interstical periapical adjacente e dentes portadores de infecção dos canais radiculares. Metodologia: os 13 pacientes incluídos no estudo foram encaminhados à Faculdade de Odontologia da Universidade Federal de Minas Gerais (Belo Horizonte, MG, Brasil). As amostras foram retiradas de dentes com necrose pulpar e nenhum paciente apresentou sintomas periapicais agudos no momento das coletas (...) Resultados: Observaram-se níveis significativamente mais baixos de TNF-α, CCL5, CCL2 / MCP-1 e IL8 em dentes com cargas bacterianas redusidas...