Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 531
Filter
1.
Rev. bras. cir. cardiovasc ; 36(1): 39-47, Jan.-Feb. 2021. tab, graf
Article in English | LILACS | ID: biblio-1155795

ABSTRACT

Abstract Introduction: Reconstruction of right ventricular outflow tract during primary repair of tetralogy of Fallot often requires the placement of a transannular patch which results in pulmonary regurgitation (PR). We compared the short-term outcomes of bicuspid polytetrafluoroethylene membrane valve versus transannular pericardial patch reconstruction of the right ventricular outflow tract. Methods: Thirty consecutive patients undergoing primary repair of tetralogy of Fallot were randomly allocated to two groups - polytetrafluoroethylene valve (PTFEV) group (n=15) and transannular pericardial patch (TAP) group (n=15). The two groups had similar preoperative demographic characteristics. We compared the short-term clinical and echocardiographic outcomes between these groups. The transthoracic echocardiographic follow-up was performed at one week, one month and six months after surgery. Results: The PTFEV group had significantly lower central venous pressure in the immediate postoperative period compared to the TAP group (7.60±2.06 vs. 10.13±1.73, P=0.002). Extubation time was significantly shorter in the PTFEV group compared to the TAP group (12.93±7.55 hrs vs. 22.23±15.11 hrs, P=0.04). PR in the PTFEV group was absent in five patients at 24 hours post-surgery. At the study endpoint, PR was absent in six, trivial in one and mild in eight patients in the PTFEV group compared to TAP group, where all 15 patients had severe PR. Conclusion: The bicuspid polytetrafluoroethylene membrane valves significantly decrease the central venous pressure in the immediate postoperative period, facilitate early extubation and, thus, prevent ventilator-related comorbidities. They achieve a high degree of pulmonary competence and do not increase the right ventricular outflow tract gradient in short-term follow-up.


Subject(s)
Humans , Infant , Pulmonary Valve/surgery , Pulmonary Valve Insufficiency , Tetralogy of Fallot/surgery , Cardiac Surgical Procedures , Polytetrafluoroethylene , Treatment Outcome
2.
Rev. Col. Bras. Cir ; 48: e20202587, 2021. graf
Article in English | LILACS | ID: biblio-1155357

ABSTRACT

ABSTRACT Objectives: the aim of this study was to compare the outcomes of a new silicone vascular prostheses with PTFE vascular prostheses, on a rabbit experimental model. Methods: forty rabbits underwent infra-renal aorta replacement with 4 mm diameter prostheses, twenty animals with PDMS and twenty animals with PTFE (control group). Retrograde aortic angiography was performed to assess patency. Histological graft samples were examined by electron microscopy to evaluate prostheses endothelialization. Results: patency rates were 100% for both grafts after 30 days; after 60 days, patency rate for PDMS was 92.3% (±7.4), and 73,8% (±13.1) at 90 days. PTFE grafts had patency rates of 87.5% (±11.7) at 60 and 90 days. No statistically significant difference was found in between groups for patency rates (p=0.62). Postoperative complications (death, paraplegia) rates (p=0.526) and aortic clamping times (p=0.299) were comparable in both groups. No statistically significant difference for stenosis was found on angiographical analysis between groups (p=0.650). Electron microscopy revealed limited anastomotic endothelial ingrowth in both prostheses. Conclusion: in this experimental model, PDMS and PTFE vascular prostheses had comparable outcomes and PDMS prosthesis could be used as a vascular graft.


RESUMO Objetivo: analisar novo tubo de silicone como material para prótese vascular e compará-lo a prótese de PTFE, em modelo experimental com coelhos. Métodos: quarenta coelhos foram submetidos a interposição, na aorta infrarrenal, de próteses de 4mm de diâmetro, sendo 20 animais com PDMS e 20 com PTFE (grupo controle). Foi realizada arteriografia retrógrada da aorta para avaliar a patência das próteses. Para avaliar a endotelização das próteses foi realizada microscopia eletrônica de maneira amostral pareada. Resultados: a patência em 30 dias foi de 100% para as duas próteses. Aos 60 dias, a taxa de patência do PDMS foi de 92,3% (± 7,4), e de 73,8% (±13,1) em 90 dias; as próteses de PTFE tiveram taxas de patência de 87,5% (± 11,7) aos 60 e 90 dias. Não foi observada diferença significativa entre as taxas de patência dos grupos (p=0,62). Não foi observada diferença entre os grupos quanto à evolução com complicações pós-operatórias (p=0,526) e quanto ao tempo de clampeamento da aorta (p=0,299). Não houve diferença significativa entre os grupos quanto ao grau de estenose das próteses (p=0,650) à avaliação angiográfica. A microscopia eletrônica mostrou crescimento endotelial limitado às regiões próximas às anastomoses nos dois tipos de próteses. Conclusões: o PDMS mostrou-se passível de utilização como prótese vascular, com resultados comparáveis aos do PTFE no modelo utilizado.


Subject(s)
Animals , Aorta/surgery , Polytetrafluoroethylene/therapeutic use , Silicones/therapeutic use , Blood Vessel Prosthesis , Polyesters , Rabbits
3.
Arq. bras. oftalmol ; 83(1): 39-42, Jan.-Feb. 2020. tab, graf
Article in English | LILACS | ID: biblio-1088957

ABSTRACT

ABSTRACT Purpose: To review the outcomes of frontalis suspension surgeries with the use of polytetrafluoroethylene in patients with blepharoptosis. Methods: A retrospective observational study analyzed the outcomes of frontalis suspension surgeries performed in a single institution from 2003 to 2018. All procedures were performed with closed incision and single pentagon techniques. Outcomes were classified as satisfactory or unsatisfactory, with satisfactory defined as a margin reflex distance of >3 mm and <1 mm between eyelids and unsatisfactory as hypocorrection, surgical complications, and asymmetry. Results: We included a total of 76 eyelids from 52 patients in our study. Within a mean postoperative follow-up of 16.8 ± 18.5 months (range, 3-95), 59 (77.6%) eyelids had a satisfactory outcome, and 17 (22.4%) were unsatisfactory (8 cases of asymmetry, 3 granulomas, 3 suture extrusions, 2 abscesses, and 1 case of cellulitis). Nine eyelids from the unsatisfactory group required reoperation. Among the patients with a follow-up of ³12 months (38 surgeries), lasting results were observed in most eyelids, except for 2 late-onset suture extrusions. Conclusion: The use of polytetrafluoroethylene in frontalis suspension surgery was shown to be predictable, safe, and lasting. Our findings support previous studies that have shown adequate functional results and low complication rates.


RESUMO Objetivo: Revisar os resultados de cirurgias de sus pensão ao músculo frontal com o uso de fio de politetrafluoretileno em pacientes com blefaroptose. Métodos: Em um estudo observacional retrospectivo, foram analisados os resultados das cirurgias de músculo frontal de uma instituição, realizadas entre 2003 e 2018. Todos os procedimentos foram realizados com incisão fechada e técnica de pentágono. Os desfechos foram classificados como satisfatórios ou insatisfatórios com definição satisfatória definida como distância margem-reflexo >3mm e <1mm entre as pálpebras e insatisfatória como hipocorreção, complicações cirúrgicas e assimetria. Resultados: Incluímos um total de 76 pálpebras de 52 pacientes em nosso estudo. Com um tempo médio de seguimento pós-operatório de 16,8 ± 18,5 meses (intervalo 3-95), 59 (77,6%) pálpebras apresentaram desfecho satisfatório e 17 (22,4%) insatisfatórios (8 casos de assimetria, 3 granulomas, 3 extrusões de sutura, 2 abscessos e 1 caso de celulite). Nove pálpebras do grupo insatisfatório necessitaram de reoperação. Entre os pacientes com seguimento ³12 meses (38 cirurgias), resultados duradouros foram observados na maioria dos casos, exceto por 2 extrusões de sutura de surgimento tardio. Conclusão: O uso de politetrafluoretileno na cirurgia de músculo frontal mostrou ser previsível, seguro e duradouro, Nossos achados corroboram com estudos prévios que mostraram resultados funcionais adequados e baixos índices de complicação.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Young Adult , Polytetrafluoroethylene/therapeutic use , Blepharoptosis/surgery , Blepharoplasty/methods , Eyelids/surgery , Oculomotor Muscles/surgery , Postoperative Complications , Reoperation , Retrospective Studies , Suture Techniques , Treatment Outcome
4.
Article in English | WPRIM | ID: wpr-741990

ABSTRACT

OBJECTIVES: The aim of this in vitro study was to test the effect of 2 finishing–polishing sequences (QB, combining a 12/15-fluted finishing bur and an EVO-Light polisher; QWB, adding a 30-fluted polishing bur after the 12/15-fluted finishing bur used in the QB sequence) on 5 nanotech-based resin composites (Filtek Z500, Ceram X Mono, Ceram X Duo, Tetric Evoceram, and Tetric Evoceram Bulk Fill) by comparing their final surface roughness and hardness values to those of a Mylar strip control group (MS). MATERIALS AND METHODS: Twelve specimens of each nanocomposite were prepared in Teflon moulds. The surface of each resin composite was finished with QB (5 samples), QWB (5 samples), or MS (2 samples), and then evaluated (60 samples). Roughness was analysed with an optical profilometer, microhardness was tested with a Vickers indenter, and the surfaces were examined by optical and scanning electron microscopy. Data were analysed using the Kruskal-Wallis test (p < 0.05) followed by the Dunn test. RESULTS: For the hardness and roughness of nanocomposite resin, the QWB sequence was significantly more effective than QB (p < 0.05). The Filtek Z500 showed significantly harder surfaces regardless of the finishing–polishing sequence (p < 0.05). CONCLUSIONS: QWB yielded the best values of surface roughness and hardness. The hardness and roughness of the 5 nanocomposites presented less significant differences when QWB was used.


Subject(s)
Composite Resins , Dental Polishing , Hardness , In Vitro Techniques , Microscopy, Electron, Scanning , Nanocomposites , Polytetrafluoroethylene
5.
Article in English | WPRIM | ID: wpr-763533

ABSTRACT

OBJECTIVE: Findings about inflammatory processes in schizophrenia are increasing day by day. Inflammatory processes in schizophrenia are associated with both its etiology and clinical symptoms. Serum high-sensitivity C-reactive protein (hsCRP) is also one of these inflammatory processes. Particularly, it is thought to be closely related to clinical findings of patients with schizophrenia. METHODS: In this study, the relationship between clinical findings of hsCRP levels of patients with drug-naïve first-episode psychosis (FEP) and patients with schizophrenia in acute exacerbation phase is investigated. Clinical findings, psychometric properties (the Scale for the Assessment of Positive Symptoms, the Scale for the Assessment of Negative Symptoms, Brief Psychiatric Rating Scale), and hsCRP levels of patients were compared. RESULTS: Forty-eight patients with FEP, 74 patients with schizophrenia in acute exacerbation phase and 54 healthy controlled volunteers are included in the study. The most substantial finding in the study is that there is a positive correlation between hsCRP levels and severity of positive symptoms of both patient groups, with FEP and with schizophrenia. The second most substantial finding is there is no significant difference between patients with FEP and schizophrenia, in terms of hsCRP. CONCLUSION: The relationship between hsCRP and positive symptom severity in two groups of patients supports the inflammatory hypothesis in the etiopathogenesis of schizophrenia. This finding is supportive of close relation between inflammatory processes and clinical findings of patient with schizophrenia.


Subject(s)
C-Reactive Protein , Humans , Polytetrafluoroethylene , Psychometrics , Psychotic Disorders , Schizophrenia , Volunteers
6.
Article in English | WPRIM | ID: wpr-741304

ABSTRACT

PURPOSE: To investigate the clinical manifestations and properties of remnant particles in the subconjunctival space after high-frequency radio-wave electrosurgery for conjunctivochalasis. METHODS: We performed a retrospective, observational case series with in vitro experimental imaging in nine eyes from eight patients who presented with small dark-gray lesions during follow-up after high-frequency radio-wave electrosurgery for conjunctivochalasis. General examination including slit-lamp examination and visual acuity testing was performed preoperatively and postoperatively. During follow-up, we evaluated remnant particles and any other complications including granuloma or conjunctival injection with slit-lamp photography and anterior optical coherence tomography. Coagulation tips were investigated with scanning electron microscope and energy dispersive X-ray spectroscopy to analyze the insulating electrode and assess changes to tips after repeated use. RESULTS: None of the patients included in this study experienced any change in visual acuity or major complications postoperatively. Small dark-gray lesions (0.3 to 0.5 mm in size) were observed in the inferior bulbar sub-conjunctival space in the location where high-frequency radio-wave electrosurgery had been performed. Cirrus high-definition optical coherence tomography images revealed focal hyper-reflection with a posterior shadow, suggesting foreign particles. Scanning electron microscopy and energy dispersive X-ray spectroscopy imaging analysis revealed peaks of carbon and fluorine complexes, consistent with the polytetrafluoroethylene coating on the electrode. CONCLUSIONS: There were no instances of inflammatory reaction, particle migration, or major complications due to particles. Physicians should be aware of the possibility of remnant polytetrafluoroethylene particles in subconjunctival tissue when using insulated coagulation tips subjected to repeat sterilization.


Subject(s)
Carbon , Electrodes , Electrosurgery , Fluorine , Follow-Up Studies , Granuloma , Humans , In Vitro Techniques , Microscopy, Electron, Scanning , Photography , Polytetrafluoroethylene , Retrospective Studies , Spectrometry, X-Ray Emission , Sterilization , Tomography, Optical Coherence , Visual Acuity
7.
Article in English | WPRIM | ID: wpr-762023

ABSTRACT

A 58-year-old male patient with severe claudication due to thrombosis of the left ilio-femoro-popliteal artery aneurysm. He also had a venous stasis ulcer with a history of multiple embolotherapy of arteriovenous malformation. Duplex sonography revealed reflux and varicose veins of the left great saphenous vein (GSV). A sequential bypass surgery was performed that consisted of excision of the left external iliac and common femoral artery aneurysm, external iliac to deep femoral interposition with an expanded polytetrafluoroethylene graft, and femoro-posterior tibial artery bypass with the reversed left GSV. Symptoms of claudication were alleviated and the chronic ulcer was healed in time. To our knowledge, this is the first report of successful bypass in a patient with arterial aneurysm, arteriovenous malformation, and venous insufficiency that can be diagnosed as an atypical case of Parkes Weber syndrome. Long-term follow-up is needed to define the fate of aneurysms and varicose vein graft.


Subject(s)
Aneurysm , Arteries , Arteriovenous Fistula , Arteriovenous Malformations , Embolization, Therapeutic , Femoral Artery , Follow-Up Studies , Humans , Male , Middle Aged , Polytetrafluoroethylene , Popliteal Artery , Saphenous Vein , Sturge-Weber Syndrome , Thrombosis , Tibial Arteries , Transplants , Ulcer , Varicose Ulcer , Varicose Veins , Venous Insufficiency
8.
Article in English | WPRIM | ID: wpr-762011

ABSTRACT

An iatrogenic internal carotid artery (ICA) pseudoaneurysm is an extremely rare complication of cervical spine surgery. Here we report an extraordinary case of massive hematemesis due to a ruptured ICA pseudoaneurysm caused by the laminoplasty plate 10 years after cervical spine surgery. Computed tomography angiography revealed a ruptured 4×10-mm left extracranial ICA pseudoaneurysm probably connected to the pharynx. Emergent surgery was performed because of the uncontrolled massive bleeding. After complete resection of the injured segment, an interposition graft with a 6-mm polytetrafluoroethylene graft was placed and the fistula tract to the pharynx was repaired.


Subject(s)
Aneurysm, False , Angiography , Carotid Artery, Internal , Fistula , Hematemesis , Hemorrhage , Laminoplasty , Pharynx , Polytetrafluoroethylene , Spine , Transplants
9.
Article in English | WPRIM | ID: wpr-762003

ABSTRACT

Iliac artery aneurysms are usually asymptomatic. Herein, we report a novel strategy for the repair of a pseudoaneurysm involving the external iliac artery using a conventional artificial graft and bare metal stent. A 76-year-old male patient presented with severe resting pain and right foot discoloration. Computed tomography angiography revealed a right distal external iliac artery pseudoaneurysm, with severe calcified occlusion at the right common and superficial femoral arteries. After exposing the right femoral artery, long-segment endarterectomy and patch angioplasty with the ipsilateral greater saphenous vein were performed. Before the completion of patch angioplasty, a surgeon-modified 8-mm expanded polytetrafluoroethylene (ePTFE) graft was inserted for complete pseudoaneurysm repair. If a commercial covered stent is not available, minimally invasive endovascular repair can be safely performed using a surgeon-modified ePTFE graft and bare metal stent.


Subject(s)
Aged , Aneurysm , Aneurysm, False , Angiography , Angioplasty , Endarterectomy , Femoral Artery , Foot , Humans , Iliac Artery , Male , Polytetrafluoroethylene , Prostheses and Implants , Saphenous Vein , Stents , Transplants
10.
Psychiatry Investigation ; : 695-703, 2019.
Article in English | WPRIM | ID: wpr-760978

ABSTRACT

OBJECTIVE: Although early intervention from the beginning of a psychotic episode is essential for a better prognosis, biomarkers predictive of symptomatic and functional improvement in early psychotic disorders are lacking. This study aimed to investigate whether the spectral power of resting-state electroencephalography (EEG) can be used as a predictive marker of the 1-year prognosis in patients with first-episode psychosis (FEP). METHODS: Twenty-four patients with FEP and matched healthy control (HC) subjects were examined with resting-state EEG at baseline. The symptomatic severity and functional status of FEP patients were assessed at baseline and reassessed after 1 year of usual treatment. Repeated measures analysis of variance was conducted to compare EEG spectral powers across the groups. Multiple regression analysis revealed EEG spectral powers predictive of symptomatic and functional improvement in FEP patients at the 1-year follow-up. RESULTS: Delta band power in the frontal and posterior regions was significantly higher in patients with FEP than in HCs. Higher delta band power in the posterior region predicted later improvement of positive symptoms and general functional status. Lower delta band power in the frontal region predicted improvement of negative symptoms and general functioning after 1 year. CONCLUSION: These results suggest that increased delta absolute power is observed from the beginning of psychotic disorders. Furthermore, decreased delta power in the frontal region and increased delta power in the posterior region might be used as a predictive marker of a better prognosis of FEP, which would aid early intervention in clinical practice.


Subject(s)
Biomarkers , Early Intervention, Educational , Electroencephalography , Follow-Up Studies , Humans , Polytetrafluoroethylene , Prognosis , Psychotic Disorders
11.
Psychiatry Investigation ; : 177-184, 2019.
Article in English | WPRIM | ID: wpr-760920

ABSTRACT

OBJECTIVE: Schizophrenia is a disabling disorder of unknown aetiology, lacking definite diagnostic method and cure. A reliable biological marker of schizophrenia is highly demanded, for which traceable immune mediators in blood could be promising candidates. We aimed to gather the best findings of neuroinflammatory markers for first-episode psychosis (FEP). METHODS: We performed an extensive narrative review of online literature on inflammation-related markers found in human FEP patients only. RESULTS: Changes to cytokine levels have been increasingly reported in schizophrenia. The peripheral levels of IL-1 (or its receptor antagonist), soluble IL-2 receptor, IL-4, IL-6, IL-8, and TNF-α have been frequently reported as increased in FEP, in a suggestive continuum from high-risk stages for psychosis. Microglia and astrocytes establish the link between this immune signalling and the synthesis of noxious tryptophan catabolism products, that cause structural damage and directly hamper normal neurotransmission. Amongst these, only 3-hydroxykynurenine has been consistently described in the blood of FEP patients. CONCLUSION: Peripheral molecules stemming from brain inflammation might provide insightful biomarkers of schizophrenia, as early as FEP or even prodromal phases, although more time- and clinically-adjusted studies are essential for their validation.


Subject(s)
Astrocytes , Biomarkers , Encephalitis , Humans , Interleukin-1 , Interleukin-4 , Interleukin-6 , Interleukin-8 , Metabolism , Methods , Microglia , Polytetrafluoroethylene , Psychotic Disorders , Receptors, Interleukin-2 , Schizophrenia , Synaptic Transmission , Tryptophan
12.
Article in English | WPRIM | ID: wpr-788823

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the biomechanical differences between human dura mater and dura mater substitutes to optimize biomimetic materials.METHODS: Four groups were investigated. Group I used cranial dura mater (n=10), group II used Gore-Tex® Expanded Cardiovascular Patch (W.L. Gore & Associates Inc., Flagstaff, AZ, USA) (n=6), group III used Durepair® (Medtronic Inc., Goleta, CA, USA) (n=6), and group IV used Tutopatch® (Tutogen Medical GmbH, Neunkirchen am Brand, Germany) (n=6). We used an axial compression machine to measure maximum tensile strength.RESULTS: The mean tensile strengths were 7.01±0.77 MPa for group I, 22.03±0.60 MPa for group II, 19.59±0.65 MPa for group III, and 3.51±0.63 MPa for group IV. The materials in groups II and III were stronger than those in group I. However, the materials in group IV were weaker than those in group I.CONCLUSION: An important dura mater graft property is biomechanical similarity to cranial human dura mater. This biomechanical study contributed to the future development of artificial dura mater substitutes with biomechanical properties similar to those of human dura mater.


Subject(s)
Biomimetic Materials , Collagen , Dura Mater , Humans , In Vitro Techniques , Mechanics , Pericardium , Polytetrafluoroethylene , Tensile Strength , Transplants
13.
Acta cir. bras ; 34(7): e201900703, 2019. tab, graf
Article in English | LILACS | ID: biblio-1038114

ABSTRACT

Abstract Purpose: To compare four types of mesh regarding visceral adhesions, inflammatory response and incorporation. Methods: Sixty Wistar rats were divided into four groups, with different meshes implanted intraperitoneally: polytetrafluoroethylene (ePTFE group); polypropylene with polydioxanone and oxidized cellulose (PCD); polypropylene (PM) and polypropylene with silicone (PMS). The variables analyzed were: area covered by adhesions, incorporation of the mesh and inflammatory reaction (evaluated histologically and by COX2 immunochemistry). Results: The PMS group had the lowest adhesion area (63.1%) and grade 1 adhesions. The ePTFE and PM groups presented almost the total area of their surface covered by adherences (99.8% and 97.7% respectively) The group ePTFE had the highest percentage of area without incorporation (42%; p <0.001) with no difference between the other meshes. The PMS group had the best incorporation rate. And the histological analysis revealed that the inflammation scores were significantly different. Conclusions: The PM mesh had higher density of adherences, larger area of adherences, adherences to organs and percentage of incorporation. ePTFE had the higher area of adherences and lower incorporation. The PMS mesh performed best in the inflammation score, had a higher incorporation and lower area of adherences, and it was considered the best type of mesh.


Subject(s)
Animals , Male , Rats , Prostheses and Implants/adverse effects , Surgical Mesh/standards , Tissue Adhesions/pathology , Incisional Hernia/surgery , Inflammation/pathology , Polypropylenes/adverse effects , Polytetrafluoroethylene/adverse effects , Postoperative Complications/prevention & control , Silicones/adverse effects , Surgical Mesh/adverse effects , Materials Testing , Viscera/physiology , Cellulose, Oxidized/adverse effects , Tissue Adhesions/prevention & control , Rats, Wistar , Statistics, Nonparametric , Abdominal Wall
14.
Article in English | WPRIM | ID: wpr-765397

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the biomechanical differences between human dura mater and dura mater substitutes to optimize biomimetic materials. METHODS: Four groups were investigated. Group I used cranial dura mater (n=10), group II used Gore-Tex® Expanded Cardiovascular Patch (W.L. Gore & Associates Inc., Flagstaff, AZ, USA) (n=6), group III used Durepair® (Medtronic Inc., Goleta, CA, USA) (n=6), and group IV used Tutopatch® (Tutogen Medical GmbH, Neunkirchen am Brand, Germany) (n=6). We used an axial compression machine to measure maximum tensile strength. RESULTS: The mean tensile strengths were 7.01±0.77 MPa for group I, 22.03±0.60 MPa for group II, 19.59±0.65 MPa for group III, and 3.51±0.63 MPa for group IV. The materials in groups II and III were stronger than those in group I. However, the materials in group IV were weaker than those in group I. CONCLUSION: An important dura mater graft property is biomechanical similarity to cranial human dura mater. This biomechanical study contributed to the future development of artificial dura mater substitutes with biomechanical properties similar to those of human dura mater.


Subject(s)
Biomimetic Materials , Collagen , Dura Mater , Humans , In Vitro Techniques , Mechanics , Pericardium , Polytetrafluoroethylene , Tensile Strength , Transplants
15.
Braz. dent. sci ; 21(4): 445-450, 2018. tab, ilus
Article in English | LILACS, BBO | ID: biblio-966307

ABSTRACT

Objective: Evaluate the bond strength of resin cements to new materials for application in intraradicular posts. Material and Methods: Five materials were evaluated: fiberglass, PET, polyethylene, polyacetal and PTFE. Two commercial resin cements (Rely X U200 and Rely X Arc) were applied on the test specimens of the materials (9x3mm) and the bonding was evaluated through the shear bond strength test, where the chisel operated with a load of 1kN and a velocity of 0.5mm/min at the cement/material interface. The data were analyzed by the Shapiro-Wilk test, followed by the two-way analysis of variance, performed with the Bonferroni post-test (α=0.05). Results: The glass fiber was statistically different from all evaluated materials (p0.05). Comparing the two cements, a statistical difference was found between Rely X U200 and Arc only for the glass fiber (p=0). Conclusion: PET, polyethylene, polyacetal and PTFE exhibited reduced bond strength compared to the glass fiber (AU)


Objetivo: Avaliar a resistência de união de cimentos resinosos a novos materiais para aplicação em pinos intrarradiculares. Material e método: Foram avaliados cinco materiais: fibra de vidro, PET, polietileno, poliacetal e PTFE. Dois cimentos resinosos comerciais (Rely X U200 e Rely X Arc) foram aplicados sobre os corpos de prova dos materias (9x3mm) e a resistência de união foi avaliada através do teste de cisalhamento, onde o cinzel atuou com carga de 1kN e velocidade de 0,5mm/min na interface cimento/material. Verificada a normalidade dos dados através do teste Shapiro-Wilk, foi realizada a análise de variância de dois fatores com pós-teste de Bonferroni (α=0,05). Resultados: a fibra de vidro foi diferente estatisticamtente de todos os materiais avaliados (p0,05). Comparando-se os dois cimentos, foi encontrada diferença estatística entre o Rely X U200 e Arc apenas para a fibra de vidro (p=0). Conclusão: PET, polietileno, poliacetal e PTFE apresentaram resistência de união reduzida comparando-se à fibra de vidro. (AU)


Subject(s)
Polytetrafluoroethylene , Polyethylene Terephthalates , Resin Cements
16.
Article in English | WPRIM | ID: wpr-742471

ABSTRACT

We report an unusual case of an 83-year-old man who was admitted with dizziness and repeated drop attacks. He was diagnosed with bilateral carotid artery occlusion and he underwent a left subclavian to left carotid bypass with ringed polytetrafluoroethylene graft. The patient's postoperative course was uneventful and no symptoms presented during a 6-month follow-up. Finally, we discuss on proper management of such patients.


Subject(s)
Aged, 80 and over , Carotid Arteries , Carotid Artery Diseases , Carotid Artery, Common , Carotid Artery, Internal , Dizziness , Follow-Up Studies , Humans , Pathology , Polytetrafluoroethylene , Syncope , Transplants , Vertebrobasilar Insufficiency
17.
Article in Korean | WPRIM | ID: wpr-719091

ABSTRACT

OBJECTIVE: This study examined the incidence and amount of air inflow during central venous catheter (CVC) insertion. METHODS: This study was an experimental study aimed at designing an apparatus to implement blood vessel and blood flow in the human body. A 1.5-m long core tube with a Teflon tube, suction rubber tube, and polyvinyl chloride tube were made. This core tube was assumed to be the blood vessel of the human body. Blood was replaced with a saline solution. The saline solution was placed higher than the core tube and flowed into the inside of the tube by gravity. The CVC was injected 15-cm deep into the core tube. The air was collected through a 3-way valve into the upper tube. The experiments were carried out by differentiating the pressure in the tube, CVC insertion step, and diameter of the end of the catheter. The experiment was repeated 10 times under the same conditions. RESULTS: The amount of air decreased with increasing pressure applied to the tube. Air was not generated when the syringe needle was injected, and the amount of air increased with increasing size of the distal end catheter. CONCLUSION: To minimize the possibility of air embolism, it is necessary to close the distal end catheter at the earliest point as soon as possible.


Subject(s)
Blood Vessels , Catheters , Central Venous Catheters , Embolism, Air , Gravitation , Human Body , Incidence , Jugular Veins , Needles , Polytetrafluoroethylene , Polyvinyl Chloride , Rubber , Sodium Chloride , Suction , Syringes
18.
Article in English | WPRIM | ID: wpr-717302

ABSTRACT

One of the complications of permanent pacemaker implantation is unintended phrenic nerve stimulation. A 15-year-old boy with a permanent pacemaker presented with chest discomfort due to synchronous chest wall contraction with pacing beats. Even after reprogramming of the pacemaker, diaphragmatic stimulation persisted. Therefore, we performed thoracoscopic phrenic nerve insulation using a Gore-Tex patch to insulate the phrenic nerve from the wire. A minimally invasive approach using a thoracoscope is a feasible option for retractable phrenic nerve stimulation after pacemaker implantation.


Subject(s)
Adolescent , Humans , Male , Minimally Invasive Surgical Procedures , Pacemaker, Artificial , Phrenic Nerve , Polytetrafluoroethylene , Thoracic Wall , Thoracoscopes , Thoracoscopy , Thorax
19.
Article in English | WPRIM | ID: wpr-716407

ABSTRACT

OBJECTIVES: The aim of this in vitro study was to evaluate the effects of the thickness and shade of 3 types of computer-aided design/computer-aided manufacturing (CAD/CAM) materials. MATERIALS AND METHODS: A total of 120 specimens of 2 shades (A1 and A3) and 2 thicknesses (1 and 2 mm) were fabricated using VITA Mark II (VM; VITA Zahnfabrik), IPS e.max CAD (IE; IvoclarVivadent), and VITA Suprinity (VS; VITA Zahnfabrik) (n = 10 per subgroup). The amount of light transmission through the ceramic specimens was measured by a radiometer (Optilux, Kerr). Light-cured resin cement samples (Choice 2, Bisco) were fabricated in a Teflon mold and activated through the various ceramics with different shades and thicknesses using an LED unit (Bluephase, IvoclarVivadent). In the control group, the resin cement sample was directly light-cured without any ceramic. Vickers microhardness indentations were made on the resin surfaces (KoopaPazhoohesh) after 24 hours of dark storage in a 37°C incubator. Data were analyzed using analysis of variance followed by the Tukey post hoc test (α = 0.05). RESULTS: Ceramic thickness and shade had significant effects on light transmission and the microhardness of all specimens (p < 0.05). The mean values of light transmittance and microhardness of the resin cement in the VM group were significantly higher than those observed in the IE and VS groups. The lowest microhardness was observed in the VS group, due to the lowest level of light transmission (p < 0.05). CONCLUSION: Greater thickness and darker shades of the 3 types of CAD/CAM ceramics significantly decreased the microhardness of the underlying resin cement.


Subject(s)
Ceramics , Curing Lights, Dental , Fungi , Hardness , In Vitro Techniques , Incubators , Polytetrafluoroethylene , Resin Cements
20.
Article in English | WPRIM | ID: wpr-716156

ABSTRACT

OBJECTIVES: The aim of this in vitro study was to evaluate the biocompatibility of newly proposed root-end filling materials, Biodentine, Micro-Mega mineral trioxide aggregate (MM-MTA), polymethylmethacrylate (PMMA) bone cement, and Smart Dentin Replacement (SDR), in comparison with contemporary root-end filling materials, intermediate restorative material (IRM), Dyract compomer, ProRoot MTA (PMTA), and Vitrebond, using human periodontal ligament (hPDL) fibroblasts. MATERIALS AND METHODS: Ten discs from each material were fabricated in sterile Teflon molds and 24-hour eluates were obtained from each root-end filling material in cell culture media after 1- or 3-day setting. hPDL fibroblasts were plated at a density of 5 × 103/well, and were incubated for 24 hours with 1:1, 1:2, 1:4, and 1:8 dilutions of eluates. Cell viability was evaluated by XTT assay. Data was statistically analysed. Apoptotic/necrotic activity of PDL cells exposed to material eluates was established by flow cytometry. RESULTS: The Vitrebond and IRM were significantly more cytotoxic than the other root-end filling materials (p < 0.05). Those cells exposed to the Biodentine and Dyract compomer eluates showed the highest survival rates (p < 0.05), while the PMTA, MM-MTA, SDR, and PMMA groups exhibited similar cell viabilities. Three-day samples were more cytotoxic than 1-day samples (p < 0.05). Eluates from the cements at 1:1 dilution were significantly more cytotoxic (p < 0.05). Vitrebond induced cell necrosis as indicated by flow cytometry. CONCLUSIONS: This in vitro study demonstrated that Biodentine and Compomer were more biocompatible than the other root-end filling materials. Vitrebond eluate caused necrotic cell death.


Subject(s)
Apicoectomy , Apoptosis , Cell Culture Techniques , Cell Death , Cell Survival , Dentin , Endodontics , Fibroblasts , Flow Cytometry , Fungi , Humans , In Vitro Techniques , Miners , Necrosis , Pemetrexed , Periodontal Ligament , Polymethyl Methacrylate , Polytetrafluoroethylene , Survival Rate
SELECTION OF CITATIONS
SEARCH DETAIL