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1.
Sci Rep ; 14(1): 6315, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491076

RESUMO

The aim was to investigate the influence of endodontic irrigation solutions and protocols on the micro-tensile bond strength (µTBS) to dentin using an etch-and-rinse (ER) or self-etch (SE) adhesive approach. Eighty extracted human molars were ground to dentin. After pretreating for 27 min (21 min-3 min-3 min) with five different endodontic irrigation protocols (Group 1: NaOCl-EDTA-NaOCl; Group 2: NaOCl-NaOCl-EDTA; Group 3: NaOCl-NaCl-NaOCl; Group 4: Dual Rinse-Dual Rinse-Dual Rinse; Group 5: NaCl-NaCl-NaCl), an ER (Optibond FL, Kerr) or a SE (Clearfil SE Bond, Kuraray) adhesive system was applied. After light-curing, composite build-ups were made and cut into dentin-composite sticks. µTBS and failure modes were analyzed. Nonparametric statistical analyses (α = 0.05) were performed for comparison of the five groups within each type of adhesive as well as between the two adhesive systems used. The use of an ER instead of a SE adhesive system resulted in significantly higher µTBS for all irrigation protocols except for group 1 (NaOCl-EDTA-NaOCl) and 2 (NaOCl-NaOCl-EDTA). A statistical difference between the five different endodontic irrigation protocols was only found within the SE adhesive group, where group 1 (NaOCl-EDTA-NaOCl) achieved highest values. The use of an ER adhesive system cancels out the effect of the endodontic irrigation solution. The highest µTBS was achieved when using a NaOCl-EDTA-NaOCl-irrigation protocol in combination with Clearfil SE Bond, which shows that the selection of the endodontic irrigation should match the corresponding SE adhesive system.


Assuntos
Cloreto de Sódio , Hipoclorito de Sódio , Humanos , Ácido Edético/farmacologia , Ácido Edético/química , Hipoclorito de Sódio/farmacologia , Hipoclorito de Sódio/química , Cloreto de Sódio/farmacologia , Dentina/química , Adesivos Dentinários/química , Teste de Materiais , Resistência à Tração
2.
Materials (Basel) ; 15(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36363058

RESUMO

This study investigated the influence of conventional (10 s at 1160 mW/cm2) and fast high-irradiance (3 s at 2850 mW/cm2) light curing on the micro-tensile bond strength (µTBS) of bulk-fill resin composites bonded to human dentin. Sixty-four extracted human molars were ground to dentin and randomly assigned into eight groups (n = 8 per group). After application of a three-step adhesive system (Optibond FL), four different bulk-fill composites (two sculptable and two flowable composites) were placed. Of these, one sculptable (Tetric PowerFill) and one flowable (Tetric PowerFlow) composite were specifically developed for fast high-irradiance light curing. Each composite was polymerized with the conventional or the fast high-irradiance light-curing protocol. The specimens were cut into dentin-composite sticks, µTBS was determined and failure modes were analyzed. Statistical analysis was performed using t-test for independent observations and one-way ANOVA. A statistical difference between the curing protocols was only found for Tetric PowerFlow, where the conventional protocol (23.8 ± 4.2 MPa) led to significantly higher values than the fast high-irradiance light-curing protocol (18.7 ± 3.7 MPa). All other composite materials showed statistically similar values for both polymerization protocols. In conclusion, the use of fast high-irradiation light curing has no negative influence on the µTBS of the investigated high-viscosity bulk-fill composites. However, it may reduce the dentin bond strength of flowable bulk-fill composite.

3.
Ann Anat ; 241: 151905, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35150863

RESUMO

The aim of this exploratory study is to analyse whether three-dimensional cinematic rendering image reconstructions offer advantages over conventional volume rendering in the visualisation of cone beam computed tomography (CBCT) and computed tomography (CT) images of the facial skeleton. This is of interest, as some information gets lost during the rendering process. This especially applies to structures in the background of the image and some surface information which can be lost. The commonly applied two-dimensional representation of CBCT or CT images in three different axes requires experience for interpretation. Cinematic rendering is a new three-dimensional post processing reconstruction technique, creating photo realistic visualisations, thus possibly enabling an easier interpretation of the images. In this study, ten investigators assessed ten separate patient cases of the orofacial skeleton. For each case, a conventional volume rendering image reconstruction and a cinematic rendering reconstruction of the same area was created. A specially designed questionnaire assessed both objective and subjective criteria of image perception. Objective criteria were assessed by predefined questions on the visual perception of anatomical image characteristics, showing the two reconstruction types of each case randomly to the investigators in two sessions. Subjective criteria were assessed via a visual analogue scale, showing both reconstructions simultaneously in a third session. The results show that cinematic rendering offers advantages especially in the evaluation of depth perception and three-dimensionality. Volume rendering shows advantages in surface sharpness. Cinematic Rendering was subjectively rated higher for almost all reconstructions. The cinematic rendering process however may cause loss of information and blurring of surfaces compared to volume rendering. With respect to the subjective impression, cinematic rendering scored better than volume rendering. The visualisation is perceived as being very close to reality.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Imageamento Tridimensional/métodos , Percepção , Esqueleto , Tomografia Computadorizada por Raios X/métodos
4.
Digestion ; 102(2): 265-273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-31962319

RESUMO

INTRODUCTION: Local recurrence remains a major problem after pancreatic head resection. Intensified histopathological work-up of surgical specimens after pancreatic head resection has revealed an increased number of incomplete resections (R1) depending on tumor infiltration front at the resection margins (RMs). It remains unclear to which extent the increased R1 resection rate has a clinical relevance for the patients' prognosis. MATERIALS AND METHODS: Pancreatic head resections between 2006 and 2012 were histologically intensively worked-up by a previously described protocol. The distance between the tumor infiltration front and the resection planes or organ surfaces was documented. The impact of the size of the tumor and an additional portal vein resection was analyzed. The effect of a R1 resection status on development and type of recurrence was evaluated. RESULTS: A total of 203 pancreatic head resections were evaluated. Different definitions of R1 resection were applied. These led to significantly different prognosis for patients. A greater distance between the tumor infiltration front and the resection plane or organ surface was associated with a better outcome for the patients. For the ventral surface, the mesopancreas and the pancreatic body these differences were statistically significant comparing the different R1 definitions. For the dorsal surface, a significant difference in prognosis was found if the tumor was >2 mm away from the resection surface. A tumor size of 3 cm was identified to play a relevant role for the prognosis. Patients who had a portal vein resection without a histologically proven infiltration showed a statistically significant higher overall survival. Patients with R1 resection were at highest risk for developing local recurrence as well as distant metastasis. CONCLUSION: Intensified histopathological work-up with an increased number of R1 resections has a clinical relevance for patients' prognosis. Tumors with a smaller size or with a greater distance to the organ surface or RM have a better outcome.


Assuntos
Neoplasias Pancreáticas , Humanos , Recidiva Local de Neoplasia , Pâncreas/diagnóstico por imagem , Pâncreas/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
5.
Front Immunol ; 11: 588245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33414784

RESUMO

Uromodulin (UMOD) is produced and secreted by tubular epithelial cells. Secreted UMOD polymerizes (pUMOD) in the tubular lumen, where it regulates salt transport and protects the kidney from bacteria and stone formation. Under various pathological conditions, pUMOD accumulates within the tubular lumen and reaches extratubular sites where it may interact with renal interstitial cells. Here, we investigated the potential of extratubular pUMOD to act as a damage associated molecular pattern (DAMP) molecule thereby creating local inflammation. We found that intrascrotal and intraperitoneal injection of pUMOD induced leukocyte recruitment in vivo and led to TNF-α secretion by F4/80 positive macrophages. Additionally, pUMOD directly affected vascular permeability and increased neutrophil extravasation independent of macrophage-released TNF-α. Interestingly, pUMOD displayed no chemotactic properties on neutrophils, did not directly activate ß2 integrins and did not upregulate adhesion molecules on endothelial cells. In obstructed neonatal murine kidneys, we observed extratubular UMOD accumulation in the renal interstitium with tubular atrophy and leukocyte infiltrates. Finally, we found extratubular UMOD deposits associated with peritubular leukocyte infiltration in kidneys from patients with inflammatory kidney diseases. Taken together, we identified extratubular pUMOD as a strong inducer of leukocyte recruitment, underlining its critical role in mounting an inflammatory response in various kidneys pathologies.


Assuntos
Inflamação/imunologia , Leucócitos/imunologia , Uromodulina/imunologia , Músculos Abdominais/imunologia , Animais , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Nefropatias/imunologia , Masculino , Camundongos Endogâmicos C57BL , Polimerização
6.
J Emerg Med ; 41(2): 128-34, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19217236

RESUMO

BACKGROUND: In 2005, the European Resuscitation Council and the American Heart Association published new guidelines for Advanced Life Support. One of the points was to reduce the time without chest compressions in the first phase of cardiac arrest. OBJECTIVE: We evaluated in a manikin model whether using the single-use laryngeal tube with suction option (LTS-D) instead of endotracheal intubation (ET) and bag-mask-valve ventilation (BMV) for emergency airway management could reduce the "no-flow time" (NFT). The NFT is defined as the time during resuscitation when no chest compressions take place. METHODS: A randomized, prospective study was undertaken with 150 volunteers who performed management of a standardized simulated cardiac arrest in a manikin. Every participant was randomized to one of three different airway management groups (LTS-D vs. ET vs. BMV). RESULTS: The LTS-D was inserted significantly faster than the ET tube (15 s vs. 44 s, respectively, p < 0.01). During the cardiac arrest simulation, establishing and performing ventilation took an average of 57 s with the LTS-D compared to 116 s with ET and 111 s with the BMV. Using the LTS-D significantly reduced NFT compared to ET and the BMV (125 s vs. 207 s vs. 160 s; p < 0.01). CONCLUSIONS: In our manikin study, NFT was reduced significantly when the LTS-D was used when compared to ET and BMV. The results of our manikin study suggest that for personnel not experienced in tracheal intubation, the LTS-D offers a good alternative to ET and BMV to manage the airway during resuscitation, and to avoid the failure to achieve tracheal intubation with the ET, and the failure to achieve adequate ventilation with the BMV.


Assuntos
Manuseio das Vias Aéreas/instrumentação , Manuseio das Vias Aéreas/métodos , Parada Cardíaca/terapia , Adulto , Atitude do Pessoal de Saúde , Feminino , Humanos , Cuidados para Prolongar a Vida/instrumentação , Cuidados para Prolongar a Vida/métodos , Masculino , Manequins , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Respiração Artificial/métodos , Sucção/educação , Sucção/instrumentação , Sucção/métodos , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
7.
BMC Emerg Med ; 8: 4, 2008 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-18402652

RESUMO

BACKGROUND: In 1999, the laryngeal tube (VBM Medizintechnik, Sulz, Germany) was introduced as a new supraglottic airway. It was designed to allow either spontaneous breathing or controlled ventilation during anaesthesia; additionally it may serve as an alternative to endotracheal intubation, or bag-mask ventilation during resuscitation. Several variations of this supraglottic airway exist. In our study, we compared ventilation with the laryngeal tube suction for single use (LTS-D) and a bag-mask device. One of the main points of the revised ERC 2005 guidelines is a low no-flow-time (NFT). The NFT is defined as the time during which no chest compression occurs. Traditionally during the first few minutes of resuscitation NFT is very high. We evaluated the hypothesis that utilization of the LTS-D could reduce the NFT compared to bag-mask ventilation (BMV) during simulated cardiac arrest in a single rescuer manikin study. METHODS: Participants were studied during a one day advanced life support (ALS) course. Two scenarios of arrhythmias requiring defibrillation were simulated in a manikin. One scenario required subjects to establish the airway with a LTS-D; alternatively, the second scenario required them to use BMV. The scenario duration was 430 seconds for the LTS-D scenario, and 420 seconds for the BMV scenario, respectively. Experienced ICU nurses were recruited as study subjects. Participants were randomly assigned to one of the two groups first (LTS-D and BMV) to establish the airway. Endpoints were the total NFT during the scenario, the successful airway management using the respective device, and participants' preference of one of the two strategies for airway management. RESULTS: Utilization of the LTS-D reduced NFT significantly (p < 0.01). Adherence to the time frame of ERC guidelines was 96% in the LTS-D group versus 30% in the BMV group. Two participants in the LTS-D group required more than one attempt to establish the LTS-D correctly. Once established, ventilation was effective in 100%. In a subjective evaluation all participants preferred the LTS-D over BMV to provide ventilation in a cardiac arrest scenario. CONCLUSION: In our manikin study, NFT was reduced significantly when using LTS-D compared to BMV. During cardiac arrest, the LTS-D might be a good alternative to BMV for providing and maintaining a patent airway. For personnel not experienced in endotracheal intubation it seems to be a safe airway device in a manikin use.


Assuntos
Máscaras Laríngeas , Cuidados para Prolongar a Vida/instrumentação , Respiração Artificial/instrumentação , Respiração Artificial/métodos , Ventiladores Mecânicos , Adolescente , Adulto , Arritmias Cardíacas/terapia , Cuidados Críticos , Educação em Enfermagem , Cardioversão Elétrica , Feminino , Parada Cardíaca , Humanos , Laringe , Cuidados para Prolongar a Vida/métodos , Masculino , Manequins , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Respiração Artificial/normas , Sucção/educação , Sucção/instrumentação , Sucção/métodos , Inquéritos e Questionários
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