Effect of a calcium hydroxide-based intracanal medicament containing N-2-methyl pyrrolidone as a vehicle against Enterococcus faecalis biofilm

Abstract This study investigated the effect of a calcium hydroxide (CH) paste (CleaniCal®) containing N-2-methyl pyrrolidone (NMP) as a vehicle on Enterococcus faecalis (E. faecalis) biofilms compared with other products containing saline (Calasept Plus™) or propylene glycol (PG) (Calcipex II®). Methodology Standardized bovine root canal specimens were used. The antibacterial effects were measured by colony-forming unit counting. The thickness of bacterial microcolonies and exopolysaccharides was assessed using confocal laser scanning microscopy. Morphological features of the biofilms were observed using field-emission scanning electron microscopy (FE-SEM). Bovine tooth blocks covered with nail polish were immersed into the vehicles and dispelling was observed. The data were analyzed using one-way analysis of variance and Tukey tests (p<0.05). Results CleaniCal® showed the highest antibacterial activity, followed by Calcipex II® (p<0.05). Moreover, NMP showed a higher antibacterial effect compared with PG (p<0.05). The thickness of bacteria and EPS in the CleaniCal® group was significantly lower than that of other materials tested (p<0.05). FE-SEM images showed the specimens treated with Calasept Plus™ were covered with biofilms, whereas the specimens treated with other medicaments were not. Notably, the specimen treated with CleaniCal® was cleaner than the one treated with Calcipex II®. Furthermore, the nail polish on the bovine tooth block immersed in NMP was completely dispelled. Conclusions CleaniCal® performed better than Calasept Plus™ and Calcipex II® in the removal efficacy of E. faecalis biofilms. The results suggest the effect might be due to the potent dissolving effect of NMP on organic substances.

Role of extracellular DNA in Enterococcus faecalis biofilm formation and its susceptibility to sodium hypochlorite

Abstract Objective This study investigated the role of extracellular deoxyribonucleic acid (eDNA) on Enterococcus faecalis ( E. faecalis ) biofilm and the susceptibility of E. faecalis to sodium hypochlorite (NaOCl). Methodology E. faecalis biofilm was formed in bovine tooth specimens and the biofilm was cultured with or without deoxyribonuclease (DNase), an inhibitor of eDNA. Then, the role of eDNA in E. faecalis growth and biofilm formation was investigated using colony forming unit (CFUs) counting, eDNA level assay, crystal violet staining, confocal laser scanning microscopy, and scanning electron microscopy. The susceptibility of E. faecalis biofilm to low (0.5%) or high (5%) NaOCl concentrations was also analyzed by CFU counting. Results CFUs and biofilm formation decreased significantly with DNase treatment (p<0.05). The microstructure of DNase-treated biofilms exhibited less structured features when compared to the control. The volume of exopolysaccharides in the DNase-treated biofilm was significantly lower than that of control (p<0.05). Moreover, the CFUs, eDNA level, biofilm formation, and exopolysaccharides volume were lower when the biofilm was treated with DNase de novo when compared to when DNase was applied to matured biofilm (p<0.05). E. faecalis in the biofilm was more susceptible to NaOCl when it was cultured with DNase (p<0.05). Furthermore, 0.5% NaOCl combined with DNase treatment was as efficient as 5% NaOCl alone regarding susceptibility (p>0.05). Conclusions Inhibition of eDNA leads to decrease of E. faecalis biofilm formation and increase of susceptibility of E. faecalis to NaOCl even at low concentrations. Therefore, our results suggest that inhibition of eDNA would be beneficial in facilitating the efficacy of NaOCl and reducing its concentration.

Influência da condição sistêmica e de hábitos no perfil periodontal: Estudo retrospectivo / The influence of systemic condition and habits in periodontal profile: a retrospective study

Objetivo: avaliar a influência do perfil sistêmico e de hábitos parafuncionais, apertamento e bruxismo no perfil periodontal da população atendida nas clínicas de Periodontia da Universidade do Sagrado Coração (USC). Material e métodos: a coleta de dados foi realizada na Universidade do Sagrado Coração, no período de agosto de 2015 a junho de 2016. Foram avaliados 230 prontuários, dos quais 88 foram incluídos na pesquisa segundo os critérios de inclusão e de exclusão adotados, chegando-se à inclusão de 38,2% dos prontuários. Resultados: as análises mostraram que pacientes diabéticos (n=11) apresentam significativamente mais sítios com profundidades de sondagem (PS) ≥ 8 mm do que pacientes não diabéticos (n=77 | p=0,01); pacientes não hipertensos (n=65) tiveram significativamente mais sítios com recessões gengivais (RG) entre 4 mm e 5 mm do que pacientes hipertensos (n=24 | p=0,049); e pacientes sem hábitos parafuncionais de apertar ou ranger os dentes (n=75) tiveram significativamente mais sítios com perda de nível de inserção clínica (NIC) entre 6 mm e 7 mm do que pacientes sem hábitos parafuncionais de apertar ou ranger os dentes (n=13 | p=0,023). Conclusão: dentro dos limites do presente estudo, pôde-se concluir que o diabetes foi confirmado como fator de risco para doenças periodontais, constatando-se maior a quantidade de sítios com grandes PS e que hábitos parafuncionais de apertamento ou bruxismo não contribuem para o aumento do NIC.

Objective: to evaluate the influence of systemic profile and parafunctional habits, clenching and bruxism on periodontal profile of the population treated in Periodontics clinics at Universidade do Sagrado Coração (USC). Material and methods: data collection was performed at the USC, in the period from August 2015 to June 2016. We evaluated 230 records in which 88 were included in the study according to the inclusion criteria and exclusion criteria, coming to the inclusion 38.2% of the records. Results: diabetic patients (n=11) showed significantly more sites with probing depths (PD) ≥ 8 mm than non-diabetic patients (n=77 | p=0.01), non-hypertensive (n=65) had significantly more sites with gingival recession (GR) between 4-5 mm than hypertensive patients (n=24) | p=0.049) and patients without parafunctional habits of clenching or grinding teeth (n=75) had significantly more sites with loss of clinical attachment level (CAL) between 6-7 mm than patients without parafunctional habits of clenching and bruxism (n=13 | p=0.023). Conclusion: within the limits of this study, it can be concluded that diabetes was confirmed as a risk factor for periodontal disease, with a greater quantity of sites with deeper PD and parafunctional habits of clenching or bruxism did not contribute to increase CAL.

Reliability, failure probability, and strength of resin-based materials for CAD/CAM restorations

ABSTRACT Objective: This study investigated the Weibull parameters and 5% fracture probability of direct, indirect composites, and CAD/CAM composites. Material and Methods: Discshaped (12 mm diameter x 1 mm thick) specimens were prepared for a direct composite [Z100 (ZO), 3M-ESPE], an indirect laboratory composite [Ceramage (CM), Shofu], and two CAD/CAM composites [Lava Ultimate (LU), 3M ESPE; Vita Enamic (VE), Vita Zahnfabrik] restorations (n=30 for each group). The specimens were polished, stored in distilled water for 24 hours at 37°C. Weibull parameters (m= modulus of Weibull, σ0= characteristic strength) and flexural strength for 5% fracture probability (σ5%) were determined using a piston-on-three-balls device at 1 MPa/s in distilled water. Statistical analysis for biaxial flexural strength analysis were performed either by both one-way ANOVA and Tukey's post hoc (α=0.05) or by Pearson's correlation test. Results: Ranking of m was: VE (19.5), LU (14.5), CM (11.7), and ZO (9.6). Ranking of σ0 (MPa) was: LU (218.1), ZO (210.4), CM (209.0), and VE (126.5). σ5% (MPa) was 177.9 for LU, 163.2 for CM, 154.7 for Z0, and 108.7 for VE. There was no significant difference in the m for ZO, CM, and LU. VE presented the highest m value and significantly higher than ZO. For σ0 and σ5%, ZO, CM, and LU were similar but higher than VE. Conclusion: The strength characteristics of CAD/ CAM composites vary according to their composition and microstructure. VE presented the lowest strength and highest Weibull modulus among the materials.

Bioactivity, physical and chemical properties of MTA mixed with propylene glycol

AbstractObjective To investigate the physical (setting time, hardness, flowability, microstructure) and chemical (pH change, calcium release, crystallinity) properties and the biological outcomes (cell survival and differentiation) of mineral trioxide aggregate (MTA) mixed using different proportions of propylene glycol (PG) and water.Material and Methods White MTA was mixed with different water/PG ratios (100/0, 80/20 and 50/50). Composition (XRD), microstructure (SEM), setting time (ASTM C266-13), flowability (ANSI/ADA 57-2000), Knoop hardness (100 g/10 s) and chemical characteristics (pH change and Ca2+ release for 7 days) were evaluated. Cell proliferation, osteo/odontoblastic gene expression and mineralization induced by MTA mixed with PG were evaluated. MTA discs (5 mm in diameter, 2 mm thick) were prepared and soaked in culture medium for 7 days. Next, the discs were removed and the medium used to culture dental pulp stem cells (DPSC) for 28 days. Cells survival was evaluated using MTS assay (24, 72 and 120 h) and differentiation with RT-PCR (ALP, OCN, Runx2, DSPP and MEPE) and alizarin red staining (7 and 14 days). Data were analysed using one-way ANOVA and Tukey’s post-hoc analysis (a=0.05).Results The addition of PG significantly increased setting time, flowability and Ca2+ release, but it compromised the hardness of the material. SEM showed that 50/50 group resulted porous material after setting due to the incomplete setting reaction, as shown by XRD analysis. The addition of PG (80/20 and 50/50) was not capable to improve cell proliferation or to enhance gene expression, and mineralized deposition of DPSC after 7 and 14 days as compared to the 100/0.Conclusion Except for flowability, the addition of PG did not promote further improvements on the chemical and physical properties evaluated, and it was not capable of enhancing the bioactivity of the MTA.

Use of assisted reproductive technology to separate sperm from human immunodeficiency virus infected men resulting in pregnancy among serodiscordant couples

Due to HIV care improvement, discordant couples more frequently seek help in order to conceive their own biological child. Besides the advance of antiretroviral therapy, unprotected intercourse is not a complete safe option, carrying a low but still present risk of HIV transmission. We report 10 serodiscordant couples in whom the male partner is HIV positive, submitted to sperm washing and intrauterine insemination. The procedure resulted in four pregnancies and no HIV transmission to mother or child was observed. Techniques of assisted reproduction can help HIV discordant couples to conceive biological offspring and is a safer option than unprotected intercourse.

Engenharia de tecidos com células-tronco de dentes decíduos e scaffolds injetáveis e a formação de polpa dental funcional / Stem cells from exfoliated deciduous teeth and self-assembling nanofiber and recombinant human collagen I scaffolds allows for the engineering of a functional dental pulp

A translação da regeneração pulpar com células tronco para a clinica requerirá o uso de scaffolds injetáveis. O objetivo foi estudar o comportamento de células tronco obtidas de dentes decíduos exfoliados (SHED) injetados em canais radiculares de pré-molares humanos com ápice aberto com scaffold de colágeno recombinante humano tipo I (rhC-I) e a base de nanofibras auto-organizáveis (SA). Para determinar a viabilidade e potencial de diferenciação de SHED in vitro, raízes nao instrumentadas foram posicionadas com o ápice em meio de cultura. SHED ressuspendida em rhC e SA foram injetadas nos canais (n=24, 5X105 células/mL). Os controles foram SHED e scaffolds sozinhos. Marcadores para diferenciação odontoblastica (DSPP, DMP-1 e MEPE) foram avaliados semanalmente por RT-PCR por 28 dias. Para avaliar a diferenciação odontoblástica e formação de tecido in vivo, SHED transuzida com GFP foram injetadas em canais radiculares (n=8, 106 célulass/mL) utilizando os mesmos grupos e implantadas subcutaneamente em camundongos imunodeprimidos. O controle (C+) foi um pré-molar humano extraído. Analise estatística foi feita com ANOVA (=0.05). Os marcadores de diferenciação odontoblástica aumentaram para SA e rhC-I mas nao nos controles. Crescimento de tecido pulpar-símile ( do que 60% do comprimento da raiz) foi observado em 75% dos implantes para SA e rhC-I e 0% nos controles. Analise de imunohistoquimica para GFP confirmou a origem tecidual a partir de SHED. PCNA e ensaio de TUNEL mostraram alta ativiade proliferativa e poucas células apoptóticas. Injeções de tetraciclina evidenciaram neoformação de dentina. A densidade microvascular e nomero de odontoblastos delineando a dentinta foi similar em rhC-I, SA e C+. A associação de SHED com scaffolds injetáveis foi capaz de originar um tecido pulpar capaz de produzir dentina e constitui um passo a mais frente ao objetivo de regeneração pulpar em pacientes humanos

The translation of dental pulp regeneration with stem cells to the clinic will require the use of injectable scaffolds. The aim was to study the behavior of stem cells from exfoliated deciduous teeth (SHED) injected in the root canal of opened-apex human premolars with either recombinant human collagen I (rhC-I) or selfassembling nanofiber (SA) scaffolds. To assess in vitro SHED viability and differentiative potential, non-instrumented roots were set with the apex in culture media. SHED were mixed in rhC-I or SA and injected into canals (n=24, 5X105 cells/mL). Controls were SHED or scaffolds alone. Odontoblastic differentiation markers (DSPP, DMP-1 and MEPE) were assessed weekly by RT-PCR for 28 days. To evaluate odontoblast differentiation and tissue formation in vivo, SHED transduced with GFP were injected in canals (n=8, 106 cells/mL) using same groups and implanted subcutaneously in immunodeficient mice. Positive control (C+) was extracted premolar. Statistic was done with ANOVA (=0.05). Odontoblastic differentiation markers increased in SA and rhC-I but not in controls. Pulp-like tissue growth ( than 60% of root length) was observed in 75% of implants for SA and rhC-I and 0% in controls. GFP staining confirmed SHEDs tissue origin. PCNA staining and TUNEL assay showed high proliferative activity and few apoptotic cells. Tetracycline injections showed newly formed dentin. Microvessel density and odontoblastic-like cell number lining dentin were similar in rhC-I, SA and C+. Injectable scaffolds and SHED allowed for the engineering of a pulp-like tissue and constitute one step forward towards the goal of dental p ulp regeneration in human patients

Engenharia de tecidos com células-tronco de dentes decíduos e scaffolds injetáveis e a formação de polpa dental funcional / Stem cells from exfoliated deciduous teeth and self-assembling nanofiber and recombinant human collagen I scaffolds allows for the engineering of a functional dental pulp

A translação da regeneração pulpar com células tronco para a clinica requerirá o uso de scaffolds injetáveis. O objetivo foi estudar o comportamento de células tronco obtidas de dentes decíduos exfoliados (SHED) injetados em canais radiculares de pré-molares humanos com ápice aberto com scaffold de colágeno recombinante humano tipo I (rhC-I) e a base de nanofibras auto-organizáveis (SA). Para determinar a viabilidade e potencial de diferenciação de SHED in vitro, raízes nao instrumentadas foram posicionadas com o ápice em meio de cultura. SHED ressuspendida em rhC e SA foram injetadas nos canais (n=24, 5X105 células/mL). Os controles foram SHED e scaffolds sozinhos. Marcadores para diferenciação odontoblastica (DSPP, DMP-1 e MEPE) foram avaliados semanalmente por RT-PCR por 28 dias. Para avaliar a diferenciação odontoblástica e formação de tecido in vivo, SHED transuzida com GFP foram injetadas em canais radiculares (n=8, 106 célulass/mL) utilizando os mesmos grupos e implantadas subcutaneamente em camundongos imunodeprimidos. O controle (C+) foi um pré-molar humano extraído. Analise estatística foi feita com ANOVA (=0.05). Os marcadores de diferenciação odontoblástica aumentaram para SA e rhC-I mas nao nos controles. Crescimento de tecido pulpar-símile ( do que 60% do comprimento da raiz) foi observado em 75% dos implantes para SA e rhC-I e 0% nos controles. Analise de imunohistoquimica para GFP confirmou a origem tecidual a partir de SHED. PCNA e ensaio de TUNEL mostraram alta ativiade proliferativa e poucas células apoptóticas. Injeções de tetraciclina evidenciaram neoformação de dentina. A densidade microvascular e nomero de odontoblastos delineando a dentinta foi similar em rhC-I, SA e C+. A associação de SHED com scaffolds injetáveis foi capaz de originar um tecido pulpar capaz de produzir dentina e constitui um passo a mais frente ao objetivo de regeneração pulpar em pacientes humanos.

The translation of dental pulp regeneration with stem cells to the clinic will require the use of injectable scaffolds. The aim was to study the behavior of stem cells from exfoliated deciduous teeth (SHED) injected in the root canal of opened-apex human premolars with either recombinant human collagen I (rhC-I) or self assembling nanofiber (SA) scaffolds. To assess in vitro SHED viability and differentiative potential, non-instrumented roots were set with the apex in culture media. SHED were mixed in rhC-I or SA and injected into canals (n=24, 5X105 cells/mL). Controls were SHED or scaffolds alone. Odontoblastic differentiation markers (DSPP, DMP-1 and MEPE) were assessed weekly by RT-PCR for 28 days. To evaluate odontoblast differentiation and tissue formation in vivo, SHED transduced with GFP were injected in canals (n=8, 106 cells/mL) using same groups and implanted subcutaneously in immunodeficient mice. Positive control (C+) was extracted premolar. Statistic was done with ANOVA (=0.05). Odontoblastic differentiation markers increased in SA and rhC-I but not in controls. Pulp-like tissue growth ( than 60% of root length) was observed in 75% of implants for SA and rhC-I and 0% in controls. GFP staining confirmed SHEDs tissue origin. PCNA staining and TUNEL assay showed high proliferative activity and few apoptotic cells. Tetracycline injections showed newly formed dentin. Microvessel density and odontoblastic-like cell number lining dentin were similar in rhC-I, SA and C+. Injectable scaffolds and SHED allowed for the engineering of a pulp-like tissue and constitute one step forward towards the goal of dental p ulp regeneration in human patients.

Effect of acid etching of glass ionomer cement surface on the microleakage of sandwich restorations

The purposes of this study were to evaluate the sealing ability of different glass ionomer cements (GICs) used for sandwich restorations and to assess the effect of acid etching of GIC on microleakage at GIC-resin composite interface. Forty cavities were prepared on the proximal surfaces of 20 permanent human premolars (2 cavities per tooth), assigned to 4 groups (n=10) and restored as follows: Group CIE - conventional GIC (CI) was applied onto the axial and cervical cavity walls, allowed setting for 5 min and acid etched (E) along the cavity margins with 35 percent phosphoric acid for 15 s, washed for 30 s and water was blotted; the adhesive system was applied and light cured for 10 s, completing the restoration with composite resin light cured for 40 s; Group CIN - same as Group CIE, except for acid etching of the CI surface; Group RME - same as CIE, but using a resin modified GIC (RMGIC); Group RMN - same as Group RME, except for acid etching of the RMGIC surface. Specimens were soaked in 1 percent methylene blue dye solution at 24°C for 24 h, rinsed under running water for 1 h, bisected longitudinally and dye penetration was measured following the ISO/TS 11405-2003 standard. Results were statistically analyzed by Kruskal-Wallis and chi-square tests (a=0.05). Dye penetration scores were as follow: CIE - 2.5; CIN - 2.5; RME - 0.9; and RMN - 0.6. The results suggest that phosphoric acid etching of GIC prior to the placement of composite resin does not improve the sealing ability of sandwich restorations. The RMGIC was more effective in preventing dye penetration at the GIC-resin composite-dentin interfaces than CI.

Influence of shade and irradiation time on the hardness of composite resins

This study tested the following hypotheses: 1. increasing light irradiation time (IT) produces greater values of superficial hardness on different depths (0 and 3 mm); and 2. a dark shade composite (A3) needs longer IT than a light shade composite (A1) to produce similar hardness. Disk-shaped specimens (n=24 per shade) were fabricated using a 3-mm-thick increment of composite resin (Z100). Specimens were randomly assigned to 3 groups (n=8) according to the IT (400 mW/cm2) at the upper (U) surface: A1-10 and A3-10: 10 s; A1-20 and A3-20: 20 s; A1-40 and A3-40: 40 s. Specimens were stored in black lightproof containers at 37ºC for 24 h before indentation in a hardness tester. Three Vickers indentations were performed on the U and lower (L) surfaces of each specimen. The indent diagonals were measured and the hardness value calculated. The results were analyzed statistically by ANOVA and Tukey's test (alpha=0.05). Statistically significant differences were found between U and L surfaces of each composite shade-IT combination (p=0.0001) and among the ITs of same shade-surface combination (p=0.0001), except between groups A1-20U and A1-40U, confirming the study hypothesis 1 and partially rejecting the hypothesis 2.

Esse estudo testou as hipóteses de que: 1. maior tempo de fotopolimerização (TF) produz maior dureza superficial em diferentes profundidades (0 e 3 mm) de resina composta (RC); 2. a cor escura (A3) de RC exige maior TF do que a RC clara (A1) para obter o mesmo grau de D. Foram fabricados 24 corpos-de-prova para cada cor de RC em único incremento de 3 mm (Z100), dividindo-os em 3 grupos (n=8), de acordo com os TF (400 mW/cm²) na superfície superior (S): A1-10 e A3-10: 10 s; A1-20 e A3-20: 20 s; A1-40 e A3-40: 40 s. Os corpos-de-prova foram armazenados sem luz, a 37ºC por 24 h, antes de aferir o grau de dureza nas superfícies S e inferior (I) com um durômetro. Foram realizadas 3 penetrações Vickers em cada superfície (S e I) dos corpos-de-prova (n=24). As diagonais das penetrações foram medidas e os valores de dureza calculados. ANOVA e Tukeyforam usados nas análises estatísticas (a=0,05). Ocorreram diferenças significativas entre S e I para cada combinação de cor-TF (p=0,0001) e entre os TF de mesma combinação cor-superfície (p=0,0001), exceto entre A1S20 e A1S40, confirmando a hipótese 1, mas rejeitando parcialmente a hipótese 2.

Seleção de cor em consultório: das escalas convencionais ao espectrofotômetro / In-office shade matching: from shade guides to spectrophotometers

A cor é um dos principais determinantes estéticos de restaurações diretas e indiretas. Tradicionalmente, a seleção de cor é realizada pelo método de comparação visual por meio de escalas convencionais que, freqüentemente, resulta na determinação imprecisa das cores, devido às deficiências técnicas das escalas e a fatores subjetivos inerentes às técnicas e ao observador. Com o objetivo de contornar as variáveis e incoerências do método convencional, aparelhos eletrônicos como os espectrofotômetros foram desenvolvidos e introduzidos no mercado. Esses dispositivos têm-se mostrado de grande utilidade, sendo capazes de fornecer resultados precisos, quantificáveis e repetíveis, aumentando o índice de sucesso na seleção e comunicação da cor e facilitando o adequado registro dos parâmetros relacionados às cores em pesquisa científica. Nesse sentido, o objetivo deste trabalho é apresentar alternativas eletrônicas para a determinação da cor na clínica odontológica.