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.

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.

Abstract: The minimally invasive endodontic access is not directly associated with tooth discoloration in the presence of bioceramic or epoxy resin-based root canal sealers. This study aimed to evaluate the influence of minimally invasive access and endodontic sealer composition on the color stability of endodontically-treated teeth, the restorative material adaptation, and the presence of remaining filling material in the pulp chamber. Endodontic access surgery was performed in maxillary central incisors, either through conservative or minimally invasive approaches, and the root was filled with AH Plus or Bio-C Sealer. The crown color was measured with a spectrophotometer at baseline and after root obturation, restoration, and specimen storage for one year in an oven. The occurrence of voids in the restoration and the remaining filling material was analyzed using micro-CT scans. The Yellowness Index (YI) and color changes (∆E00) were calculated after each color measurement. Data of micro-CT were submitted to 2-way ANOVA, and YI and ∆E00 were analyzed with repeated-measures ANOVA. Pair-wise comparisons were performed with Tukey's test (α = 0.05). The experimental conditions had no effect on the presence of the remaining material. The minimally invasive access associated with Bio-C Sealer resulted in more voids between the restoration and the remaining filling material. Only the evaluation time affected YI and ∆E00 values. Specimens became more yellow after filling and storage in the oven (the highest ∆E00 values). The present study showed that sealer and minimally invasive cavities are not associated with crown color stability following endodontic treatment.

Resumo Estabelecemos um modelo de prova de conceito para o tratamento biológico de lesões periapicais utilizando esferoides de células-tronco. Uma linhagem de células- tronco mesenquimais isoladas da polpa dentária de dentes decíduos (células SHED) foi cultivada em monocamada 2D e posteriormente em esferoides multicelulares em 3D. Uma imagem de uma lesão periapical de um incisivo lateral superior foi obtida por tomografia micro computadorizada, a qual foi usada como modelo para impressão 3D de resina fotopolimérica, gerando um molde negativo da lesão. O modelo negativo foi utilizado para preparar um modelo positivo da cavidade da lesão periapical em gel de agarose. Células SHED cultivadas em monocamadas ou como esferoides foram semeadas no molde positivo da lesão antes ou após a diferenciação osteoblástica. Os resultados mostraram que, em comparação com células cultivadas em monocamadas, os esferoides apresentaram celularidade uniforme e maior viabilidade dentro da cavidade da lesão, acompanhada de redução temporal na expressão de RNAs mensageiros tipicamente expressos por células-tronco (CD13, CD29, CD44, CD73 e CD90). Concomitantemente, houve um aumento na expressão de marcadores proteicos que caracterizam a diferenciação osteoblástica (RUNX2, ALP e BGLAP). Esses resultados proporcionam uma nova perspectiva para a endodontia regenerativa com o uso de esferoides preparados com células SHED para reparar lesões periapicais.

Abstract We established a proof-of-concept model system for the biological healing of periapical lesions using stem cell spheroids. Mesenchymal stem cells from human exfoliated deciduous teeth (SHED) were cultured in a 2D monolayer and then as 3D multicellular spheroids. An image of a periapical lesion of an upper lateral incisor tooth was obtained by computed tomography and was used as a model for photopolymer resin 3D printing to generate a negative frame of the lesion. The negative model served to prepare a positive model of the periapical lesion cavity in an agarose gel. SHED that were cultured in monolayers or as spheroids were seeded in the positive lesion mold before or after osteoblastic differentiation. The results showed that compared to cells cultured in monolayers, spheroids exhibited uniform cellularity and a greater viability within the lesion cavity, which was accompanied by a temporal reduction in the expression of CD13, CD29, CD44, CD73, and CD90 mRNAs that are typically expressed by stem cells. Concomitantly, the expression of markers that characterize osteoblastic differentiation (RUNX2, ALP, and BGLAP) increased. These results provide a new perspective for regenerative endodontics with the use of SHED-derived spheroids to repair periapical lesions.

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.

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.

Este estudo in vitro comparou a resistência à remoção por tração de núcleos metálicos fundidos em liga de Cu-Al (Goldent-LA) cilíndricos, jateados, de comprimento constante igual a 9 mm, cimentados com cimento de fosfato de zinco e com três diferentes diâmetros: 0,9 mm, 1,3 mm e 1,7 mm. Trinta e seis caninos superiores hígidos tiveram suas coroas seccionadas, sendo as raízes incluídas em blocos de resina acrílica, e os canais, tratados endodonticamente. Os dentes foram divididos em três grupos para serem preparados e padronizados com o auxílio de um paralelômetro com as seguintes brocas: Grupo 1 - Largo nº 2; Grupo 2 - Largo nº 4; Grupo 3 - Largo nº 6. Os núcleos foram moldados com resina acrílica ativada quimicamente e, após a fundição, foram jateados e tiveram as suas dimensões conferidas com um paquímetro digital. Após a cimentação, os corpos-de-prova foram armazenados em água destilada durante 7 dias, em estufa a 37ºC e, posteriormente, submetidos a teste de tração em uma máquina universal de ensaios Instron 4444. Com a análise estatística dos resultados, pôde-se concluir que não houve diferença estatisticamente significante entre os grupos testados. A variação do diâmetro em núcleos cilíndricos jateados cimentados com fosfato de zinco não afetou a resistência à remoção.

This study compared the resistance to removal by traction of abraded cylindrical metal cast posts of Cu-Al (Goldent-LA). The posts had constant length (9 mm) and three different diameters (0.9, 1.3 and 1.7 mm), and were cemented with zinc phosphate cement. The crowns of 36 sound maxillary canines were sectioned, the roots were immersed in resin blocks and the root canals were endodontically treated. The teeth were divided into three groups to be prepared and standardized with the use of a parallelometer with the following burs: Group 1 - Largo n. 2; Group 2 - Largo n. 4; Group 3 - Largo n. 6. The posts were molded with chemically activated resin and after casting they were abraded and their dimensions were confirmed with a digital caliper. After cementation of the posts in the prepared root canals, the samples were kept at 37ºC in distilled water for 7 days and subsequently submitted to the traction test in a universal testing machine (Instron 4444). The results showed no statistical difference between the groups. Diameter variation (0.9 mm, 1.3 mm and 1.7 mm) in abraded cylindrical posts cemented with zinc phosphate did not affect resistance to removal.

O objetivo deste estudo foi testar o efeito antimicrobiano do hipoclorito de sódio a 2% e da clorexidina a 2% por meio de dois métodos: difusão em agar e exposição direta. Cinco microrganismos: Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Bacillus subtilis, Candida albicans, e uma mistura foram utilizados. As cepas foram inoculadas em BHI e incubadas a 37ºC por 24 h. Para o teste de difusão em agar, 18 placas de Petri com 20 ml de BHIA foram inoculadas com 0,1 ml das suspensões microbianas, com auxílio de swab esterilizado, de modo a se obter um crescimento confluente. 54 discos de papel com 9 mm de diâmetro foram imersos nas soluções experimentais durante 1 min. A seguir, em cada placa, 3 discos de papel contendo uma das soluções irrigantes foram colocadas sobre a superfície do BHIA. As placas foram mantidas por 1 h em temperatura ambiente, e incubadas a 37ºC por 48 h. Os diâmetros dos halos de inibição microbiana foram medidos sobre os discos de papel contendo as substâncias, valendo-se de duas medidas de forma perpendicular entre si, sendo obtido a média de seus tamanhos. Para o teste de exposição direta, 162 pontas de papel absorvente esterilizadas nº 50 foram imersas na suspensão experimental por 5 min, e foram colocadas sobre uma placa de Petri e cobertas com 10 ml de uma das soluções irrigantes, ou com a água destilada. Em intervalos de 5, 10 e 30 min, as pontas de papel foram removidas do contato com as soluções teste e individualmente transportadas e imersas 7 ml de Letheen Broth, e incubadas a 37ºC for 48 h. O crescimento microbiano foi avaliado pela turbidade do meio de cultura. Um inóculo de 0.1 ml obtido do Letheen Broth foi transferido para 7 ml of BHI, e incubado nas mesmas condições descritas. O crescimento microbiano foi novamente avaliado pela turbidade do meio de cultura. Os resultados mostraram efetividade antimicrobiana para as duas soluções irrigadoras testadas. A magnitude do efeito antimicrobiano foi influenciada pelo método experimental, pelos microrganismos e pelo tempo de exposição.

The objective of this study was to analyze the antimicrobial effect of 2% sodium hypochlorite (NaOCl) and 2% chlorhexidine (CHX) by agar diffusion test and by direct exposure test. Five microorganisms: Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Bacillus subtilis, Candida albicans, and one mixture of these were used. These strains were inoculated in brain heart infusion (BHI) and incubated at 37ºC for 24 h. For the agar diffusion test (ADT), 18 Petri plates with 20 ml of BHI agar were inoculated with 0.1 ml of the microbial suspensions, using sterile swabs that were spread on the medium, obtaining growth in junction. Fifty-four paper disks (9 mm in diameter) were immersed in the experimental solutions for 1 min. Subsequently, three papers disks containing one of the substances were placed on the BHI agar surface in each agar plate. The plates were maintained for 1 h at room temperature, and then incubated at 37ºC for 48 h. The diameter of microbial inhibition was measured around the papers disks containing the substances. For the direct exposure test, 162 #50 sterile absorbent paper points were immersed in the experimental suspensions for 5 min, and were then placed on Petri plates and covered with one of the irrigant solutions, or with sterile distilled water (control group). After intervals of 5, 10 and 30 min, the paper points were removed from contact with the solutions and individually immersed in 7 ml of Letheen Broth, followed by incubation at 37ºC for 48 h. Microbial growth was evaluated by turbidity of the culture medium. A 0.1 ml inoculum obtained from the Letheen Broth was transferred to 7 ml of BHI, and incubated at 37ºC for 48 h. Bacterial growth was again evaluated by turbidity of the culture medium. Gram stain of BHI cultures was used for verification of contamination and growth was determined by macroscopic and microscopic examination. The best performance of antimicrobial effectiveness of NaOCl was observed in the direct exposure test, and of CHX was observed in the agar diffusion test. The magnitude of antimicrobial effect was influenced by the experimental methods, biological indicators and exposure time.

A eficiência de três desinfetantes usados em Odontologia foi estudada na descontaminação de 60 cones de guta-percha contaminados com culturas puras e padronizadas de cinco cepas de microrganismos (Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, Candida albicans ATCC CBS-ICB/USP 562, Bacillus subtilis em esporos ATCC 6633 e Streptococcus mutans ATCC 25175). Os cones foram tratados com solução aquosa de polivinilpirrolidona-iodo 10% (PVP-I; Grupos 1 e 2), solução aquosa de hipoclorito de sódio 5,25% (Grupos 3 e 4) e pastilhas de formaldeído (Grupo 5). Nossos resultados indicam que todos os agentes químicos foram eficientes para a esterilização a frio dos cones de guta-percha em curtos espaços de tempo.

This study evaluated the effectiveness of three disinfectants used in Dentistry for decontamination of gutta-percha cones. Sixty gutta-percha cones were contaminated with standardized pure cultures of five species of microorganisms (Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, Candida albicans ATCC CBS-ICB/USP 562, Bacillus subtilis spores ATCC 6633 and Streptococcus mutans ATCC 25175). The cones were treated with 10% polyvinylpyrrolidone-iodine aqueous solution (PVP-I; Groups 1 and 2), 5.25% aqueous sodium hypochlorite (Groups 3 and 4) and paraformaldehyde tablets (Group 5). All chemical agents were efficient for the cold sterilization of gutta-percha cones in short time periods.

O objetivo deste estudo foi verificar a resistência à tração de coroas metálicas fixadas com diferentes cimentos e submetidas à termociclagem. Setenta e duas coroas foram fundidas com liga de Ni-Cr Verabond II e cimentadas em preparos padronizados com 8º de paredes laterais e acabamento cervical com ombro reto, ombro biseldo 20º e ombro chanfrado 45º. As coroas foram separadas em três grupos de oito elementos de acordo com os cimentos: fosfato de zinco (SS White), ionômero de vidro modificado por resina Vitremer (3M ) e resinoso Rely X (3M), e submetidas a 500 ciclos térmicos em banhos de 5ºC e 55ºC. A retenção foi avaliada de acordo com a carga de tração (kgf) necessária para separar a coroa do preparo, numa máquina Instron com velocidade de 0,5 mm/minuto. Os resultados submetidos à análise de variância e ao teste de Tukey (5%) mostraram que a retenção mais eficiente foi obtida com o cimento resinoso, independentemente do tipo de acabamento cervical.

The relationship between metallic cast crowns and tensile strength according to cement types submitted to thermocycling was studied. Seventy-two metallic crowns were cast with Verabond II Ni-Cr alloy and cemented in standardized preparations with 10º tapering. Three types of finishing line (45-degree chamfered, 20-degree bevel shoulder and right shoulder) were made with diamond burs on bovine teeth. Twenty-four metallic crowns in each group were randomly subdivided into three subgroups of 8 samples each according to the cement used: SS White zinc phosphate cement, Vitremer resin-modified glass ionomer cement, and Rely X resin cement and were submitted to thermocycling. Retention was evaluated according to tensile load required to displace the metallic cast crowns from tooth preparations with an Instron testing machine. ANOVA and Tukey's test showed a statistically significant difference among luting materials, with greater results for Rely X resin cement (24.9 kgf) followed by SS White zinc phosphate cement (13.3 kgf) and Vitremer resin-modified glass ionomer cement (10.1 kgf). The finishing line types did not influence the tensile resistance of the crowns fixed with the three cements. Increased tensile resistance of metallic crowns fixed on bovine teeth was obtained with resin cement, independent of the finishing line types.

Estudou-se o efeito da solução de EGTA (ácido bis(2-aminoetil) etilenoglicol-N,N,N',N'-tetraacético) a 1, 3 e 5% sobre a microdureza da dentina radicular, no terço cervical de dentes humanos. Utilizaram-se 5 incisivos centrais superiores recém-extraídos. Os dentes foram seccionados transversalmente na junção esmalte/cemento e as coroas foram desprezadas. As raízes foram incluídas em blocos de resina acrílica de rápida polimerização, colocadas em uma máquina de corte e seccionadas transversalmente de 1 em 1 milímetro. O segundo corte do terço cervical da raiz de cada dente foi selecionado para o experimento. Cada corte foi dividido em quatro partes sendo que cada parte foi colocada sobre um disco de acrílico, que servia de suporte para a medida de microdureza. Aplicou-se 50 µl da solução teste durante cinco minutos sobre cada superfície de dentina. Água destilada e deionizada foi utilizada como controle. A microdureza da dentina foi medida em um aparelho de dureza Vickers com 50 gramas de carga e 15 segundos de aplicação. A análise estatística dos resultados mostrou que as 3 soluções quelantes reduziram significantemente a microdureza da dentina quando comparado com a água. As soluções de EGTA a 1, 3 e 5% apresentaram-se estatisticamente diferentes entre si.

The effect of 1%, 3% and 5% EGTA (ethylene glycol-bis-(b-amino-ethyl ether) N,N,N´,N´-tetra-acetic acid) on the microhardness of root dentin of the cervical third of human teeth was studied. Five newly extracted maxillary incisors were sectioned transversely at the cementoenamel junction, and the crowns were discarded. The roots were embedded in blocks of high-speed polymerized acrylic resin and cut transversely into 1-mm sections. The second section of the cervical third of the root of each tooth was sectioned and divided into four parts. Each part was placed on an acrylic disc that was used as a base for microhardness measurement. Fifty microliters of 1% EGTA, 3% EGTA, or 5% EGTA were applied to the dentin surface. Deionized and distilled water was used as control. Dentin microhardness was then measured with a load of 50 g for 15 s. Statistical analysis showed that the three concentrations of the chelating solution EGTA significantly reduced dentin microhardness when compared with water (ANOVA, p<0.01), and that there was a statistically significant difference among the three solutions (Tukey test, p<0.05).

No presente estudo, analisou-se o efeito da adição de diferentes tipos de breus e resinas hidrogenadas ao pó do cimento de GROSSMAN sobre o tempo de endurecimento. Os experimentos foram realizados de acordo com a Especificação 57 para materiais obturadores de canais radiculares da American Dental Association (ADA). Para análise, foram aviados pós do cimento de GROSSMAN com diferentes tipos de breu (X, WW e WG) e resinas hidrogenadas (Stabylite e Stabylite éster 10). Os estudos das propriedades físico-químicas dos cimentos tipo GROSSMAN obtidos de diferentes tipos de breus e resinas hidrogenadas interferem no tempo de endurecimento do cimento. A resina hidrogenada, obtida do processo de hidrogenação tem o pH mais alto, provocando um aumento do tempo de endurecimento do cimento em relação aos breus tipo X, WW e WG, que têm pH mais ácido.

In this study, the effect on the setting time by the addition of different kinds of rosin and hydrogenated resin on the Grossman cement powder was evaluated. The experiments were carried out following the American Dental Association’s specification number 57 for root canal sealers. For this analysis, different Grossman cement powders were prepared using different rosins (X, WW and WG) and hydrogenated resins (Staybelite and Staybelite ester 10). The study of the physicochemical properties of the Grossman cements obtained the different kinds of rosins and hydrogenated resins interference on the cement’s setting time. The hydrogenated resin, having a higher pH, increased the setting time of the cement when compared to the X, WW and WG rosins.