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2.
Int J Oral Maxillofac Implants ; 39(1): 119-126, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38416005

RESUMO

PURPOSE: This in vitro study investigated the effect of implant geometry and diameter on the rotational load fatigue performance of an implant system with an internal conical connection with microthreads. MATERIALS AND METHODS: Regular (4.2 mm) and wide-diameter (4.8 mm) Astra Tech EV implants with straight (S) and conical (C) geometries were tested with their corresponding titanium abutments, comprising four test groups: 4.2-mm S (Group 1), 4.2-mm C (Group 2), 4.8-mm S (Group 3), and 4.8-mm C (Group 4). Five samples were included in each group. Customized brass implant holders and abutment holders were machined. A rotational load fatigue machine was used to apply a sinusoidally varying load to the implant-abutment interface at an angle of 45 degrees to produce an effective bending moment of 35 Ncm at a frequency of 14 Hz (air temperature: 20°C). The number of cycles to failure was recorded, with the upper limit set at 5 × 106 cycles. Results were analyzed using ANOVA. Failed samples were examined with a scanning electron microscope to evaluate the mode of failure. RESULTS: Of the 20 total samples, 2 failed, with Groups 1 and 2 each reporting one failure. Abutment and abutment screw fracture were observed in the failed sample in Group 1, while implant and abutment screw fracture occurred in the failed sample in Group 2. All wide-diameter implants ran beyond the cut-off without failure, but abutment screw loosening was noted in one sample in Group 3. No significant difference was found between implant groups of different geometries and diameters. Damage to the abutments and the implant internal surface were noted in all failed samples. CONCLUSIONS: While no significant differences were found between the test groups, failures were observed only in the regular-diameter group. The abutment and abutment screw fractured deep within the implant, and the implant fractured below the simulated bone level. These modes of failure may pose a significant clinical challenge during retrieval of these components.


Assuntos
Implantes Dentários , Falha de Equipamento , Teste de Materiais , Projetos de Pesquisa , Temperatura , Titânio
3.
Pediatr Emerg Care ; 40(2): 166-168, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38295198

RESUMO

ABSTRACT: The spontaneous intravesicular knotting of a feeding tube used for urethral catheterization is a rare but documented complication. The reported incidence in the world literature is 0.2 per 100,000, with only 40 cases reported. Removal of these intravesicular knots has been attempted in a number of ways, such as the use of a guide wire to untangle the knot, use of excess lubrication and traction with or without anesthetic, and percutaneous or open cystostomy. This cystoscopic technique for removal has not been previously described.Based on our experience and published recommendations, we formulate an algorithm for removal. We outline steps for prevention and techniques from simple to complex, which can be used to remove knotted catheters.Although a rare complication of catheterization in children, catheter knotting can be troublesome. Following the steps suggested in this algorithm may avoid the use of more invasive techniques for removal.


Assuntos
Remoção de Dispositivo , Cateteres Urinários , Criança , Humanos , Cateteres Urinários/efeitos adversos , Remoção de Dispositivo/métodos , Falha de Equipamento , Cateterismo Urinário/efeitos adversos , Nutrição Enteral
5.
Stud Health Technol Inform ; 310: 1450-1451, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38269691

RESUMO

The purpose of this study was to evaluate the accuracy of deep neural machine translation focused on medical device adverse event terminology. 10 models were obtained, and their English-to-Japanese translation accuracy was evaluated using quantitative and qualitative measures. No significant difference was found in the quantitative index except for a few pairs. In the qualitative evaluation, there was a significant difference and googletrans and GPT-3 were regarded as useful models.


Assuntos
Inteligência Artificial , Falha de Equipamento , Tradução , Terminologia como Assunto
6.
Eur Endod J ; 9(2): 133 - 138, 2024 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-38268112

RESUMO

OBJECTIVE: To evaluate the impact of different file access angles and root canal curvature's location on the fatigue failure of One Curve (OC) and E3 Azure (EZ) NiTi files using a dynamic model at simulated body temperature. METHODS: Eighty new instruments with similar tip sizes and taper (#25/0.06) from two NiTi rotary systems, One Curve and E3 Azure, were tested at simulated body temperatures (37°C) using a custom-made dynamic cyclic fatigue device. Instruments were divided into four subgroups according to the location of root canal curvature (a coronal curve 5 mm from the root canal orifice and an apical curve 10 mm from the root canal orifice) and the angle of file access (0° or 30°). Instruments were operated in simulated stainless-steel canals having a 60° curve and a 3 mm radius. A custom-made device produced controlled vertical pecks during file rotation. Time to failure (sec) was registered, and the length of the fragment segments was measured (mm). Data were analysed statistically with One-Way ANOVA and Tukey post hoc tests. The significance level was set at 5%. All separated instruments were examined by scanning electron microscope. RESULTS: One-way ANOVA (p<0.05) found a significant difference among the tested instruments. Post Hoc analysis revealed lower cyclic fatigue resistance when the angle of file access was 30º, and the root canal curvature was located coronally for both files (p<0.0001). Three-way ANOVA showed that the angle of file access was the most influential contributor to cyclic fatigue, followed by the location of file curvature and, finally, the file type (p<0.0001). The fractographic examination revealed a predominantly ductile fracture mode for all tested instruments. The lengths of all fractured segments showed no significant difference (p>0.05), indicating an accurate trajectory during testing. CONCLUSION: OC files had superior cyclic fatigue resistance than EZ files; coronal curvatures negatively impacted cyclic fatigue resistance compared to apical curvatures, while the angle of file access presented the highest impact on dynamic cyclic fatigue.


Assuntos
Ligas , Ligas Dentárias , Instrumentos Odontológicos , Níquel , Titânio , Falha de Equipamento , Preparo de Canal Radicular
7.
J Cardiovasc Electrophysiol ; 35(2): 230-237, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38047467

RESUMO

INTRODUCTION: The extravascular implantable cardioverter defibrillator (EV ICD) has extended projected battery longevity compared to the subcutaneous implantable cardioverter defibrillator (S-ICD). This study used modeling to characterize the need for generator changes, long-term complications, and overall costs for both the EV ICD and S-ICD in healthcare systems of various countries. METHODS: Battery longevity data were modeled using a Markov model from averages reported in device labeling for the S-ICD and with engineering estimates based on real life usage from EV ICD Pivotal Study patient data to introduce variability. Clinical demographic data were derived from published literature. The primary outcomes were defined as the number of generator replacement surgeries, complications, and total healthcare system costs due to battery depletion over the expected lifetime of patients receiving EV ICD or S-ICD therapy. RESULTS: Average modeled battery longevity was determined to be 7.3 years for the S-ICD versus 11.8 years for the EV ICD. The probability of a complication after a replacement procedure was 1.4%, with an operative mortality rate of 0.02%. The use of EV ICD was associated with 1.4-1.6 fewer replacements on average over an expected patient lifetime as compared to S-ICD and a 24.3%-26.0% reduction in cost. A one-way sensitivity analysis of the model for the US healthcare system found that use of an EV ICD resulted in a reduction in replacement surgeries of greater than 1 (1.1-1.6) along with five-figure cost savings in all scenarios ($18 602-$40 948). CONCLUSION: The longer projected battery life of the EV ICD has the potential to meaningfully reduce long-term morbidity and healthcare resources related to generator changes from the perspective of multiple diverse healthcare systems.


Assuntos
Desfibriladores Implantáveis , Humanos , Falha de Equipamento , Cardioversão Elétrica/efeitos adversos , Previsões , Redução de Custos
8.
Acta Biomater ; 173: 51-65, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37972883

RESUMO

It is well documented that overly stiff skeletal replacement and fixation devices may fail and require revision surgery. Recent attempts to better support healing and sustain healed bone have looked at stiffness-matching of these devices to the desired role of limiting the stress on fractured or engrafted bone to compressive loads and, after the reconstructed bone has healed, to ensure that reconstructive medical devices (implants) interrupt the normal loading pattern as little as possible. The mechanical performance of these devices can be optimized by adjusting their location, integration/fastening, material(s), geometry (external and internal), and surface properties. This review highlights recent research that focuses on the optimal design of skeletal reconstruction devices to perform during and after healing as the mechanical regime changes. Previous studies have considered auxetic materials, homogeneous or gradient (i.e., adaptive) porosity, surface modification to enhance device/bone integration, and choosing the device's attachment location to ensure good osseointegration and resilient load transduction. By combining some or all of these factors, device designers work hard to avoid problems brought about by unsustainable stress shielding or stress concentrations as a means of creating sustainable stress-strain relationships that best repair and sustain a surgically reconstructed skeletal site. STATEMENT OF SIGNIFICANCE: Although standard-of-care skeletal reconstruction devices will usually allow normal healing and improved comfort for the patient during normal activities, there may be significant disadvantages during long-term use. Stress shielding and stress concentration are amongst the most common causes of failure of a metallic device. This review highlights recent developments in devices for skeletal reconstruction that match the stiffness, while not interrupting the normal loading pattern of a healthy bone, and help to combat stress shielding and stress concentration. This review summarises various approaches to achieve stiffness-matching: application of materials with modulus close to that of the bone; adaptation of geometry with pre-defined mechanical properties; and/or surface modification that ensures good integration and proper load transfer to the bone.


Assuntos
Fraturas Ósseas , Humanos , Próteses e Implantes , Osseointegração , Porosidade , Falha de Equipamento , Estresse Mecânico
9.
Vasc Endovascular Surg ; 58(2): 129-135, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37450890

RESUMO

OBJECTIVE: Endovascular aortic repair (EVAR) for elective and emergency infrarenal aortic pathologies is the primary approach for treatment nowadays. During such procedure, the suture-mediated closure device (SMCD) (Perclose ProGlideTM, Abbott Laboratories, Chicago, IL, USA) is commonly used. This study aimed to identify potential contributors for SMCD failure in a patient cohort of elective and emergency EVAR. METHODS: Archived medical records from patients who underwent EVAR for aortic pathologies in elective and emergency setting at the University Hospital Düsseldorf, Germany were included. Patient's co-morbidities, access vessel morphologies and hemostasis-related blood parameters were evaluated on their association with SMCD failure applying different statistical methods. RESULTS: A total of 71 patients (139 femoral accesses) was included. The mean age was 73.5 ± 8.4 years. Overall SMCD failure rate was 4.3%, 4.1% for elective and 5.9% for emergency cases, respectively. Total procedure time was longer for the SMCD failure group (323 ± 117.8 min vs 171 ± 43.7 min). The calcification status of the common femoral artery (CFA), the diameter of the aortic bifurcation, and dual anti-platelet therapy (DAPT) on the medication plan prior to the procedure were associated with SMCD failure. Univariate binary logistic regression analysis nominated several potentially relevant predictors for SMCD failure who underwent subsequent multivariable binary logistic regression analysis. Here, DAPT on the medication plan was identified as being promising in predicting SMCD failure (OR 30.5), while anterior plaque formation in the CFA maintained as only statistically relevant determinant (OR 44.9). CONCLUSIONS: This study confirms the CFA calcification status to be associated with SMCD failure. Although discontinued prior to endovascular treatment, DAPT was also found to be associated with SMCD failure. Our results may advocate to perform obligatory platelet testing prior to EVAR to maximize patient safety.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Idoso , Idoso de 80 Anos ou mais , Correção Endovascular de Aneurisma , Inibidores da Agregação Plaquetária , Resultado do Tratamento , Aorta Abdominal , Falha de Equipamento , Suturas , Aneurisma da Aorta Abdominal/cirurgia , Estudos Retrospectivos , Implante de Prótese Vascular/efeitos adversos , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Fatores de Risco
10.
Am J Otolaryngol ; 45(2): 104153, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38113778

RESUMO

OBJECTIVE: To identify and report a single center experience with upper airway stimulator device-related failures. STUDY DESIGN: Retrospective case series. SETTING: Single tertiary academic center. METHODS: Retrospective data on 352 patients who underwent UAS surgery with an Inspire device from 2016 to 2023 was collected, including demographics, comorbidities, and nature of device failure requiring revision surgery. RESULTS: Out of the 348 patients included in our analysis, 16 (4.6 %) required revision due to device failure, with an average interval of 772 days (∼2 years) between initial implant and revision. Most failures were attributed to respiratory sensing lead damage (n = 11, 68.8 %), resulting in high system impedance and subsequent device malfunction. Lead fracture causes varied, including idiopathic occurrences and potential trauma. Lead migration was noted in one case (6.3 %), where the hypoglossal electrode detached from the nerve. Two patients (12.3 %) required implantable pulse generator (IPG) replacement, one after experiencing trauma and the other due to unclear source of malfunction. One patient (6.3 %) required complete system replacement following high lead impedance and absent tongue motion. The last patient required replacement of both the IPG and respiratory lead after experiencing high lead impedance (6.3 %). CONCLUSION: Respiratory sensing lead fracture emerged as the leading cause of device failure in this cohort, underscoring the need to address this under-reported issue, potentially linked to the time lapse after device implantation.


Assuntos
Terapia por Estimulação Elétrica , Humanos , Estudos Retrospectivos , Eletrodos Implantados/efeitos adversos , Reoperação , Falha de Equipamento
12.
BMC Cardiovasc Disord ; 23(1): 609, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087189

RESUMO

BACKGROUND: There is a lack of evidence regarding contemporary implantable cardioverter-defibrillator (ICD) battery longevity. Our aim was to assess battery longevity in ICDs in a real-world setting. METHODS: Retrospective cross-sectional single center study of a prospectively collected database of consecutive patients who underwent ICD implantation from January 2010 to December 2015. Clinical data and battery longevity of all manufacturers were collected. RESULTS: A total of 351 patients (84.6% males, mean age of 61 ± 12 years) were included in the study (292 VVI; 6 VDD; 53 DDD). All manufacturers (Abbott, Biotronik, Boston, Medtronic and Microport) were equally represented in the study (p = 0.110). Median battery longevity was 10.8 years (11 years for VVI and 8.5 for DDD). After a follow-up time of 5 years, 98% of VVI and DDD were still in service (vs. industry-projected longevity of 98%). During this time, 89 patients (25.4%) underwent device replacement - 69 patients (77.5%) due to battery depletion, 6 patients due to infection, 3 patients due to dysfunction and 13 patients due to upgrade to CRT-D. Patients with Medtronic or Biotronik ICDs had a greater probability of being replaced earlier due to battery depletion (Biotronik HR 6.87, 95% CI 2.54-18.58, p < 0.001; Medtronic HR 6.08, 95% CI 2.45-15.06 p < 0.001). CONCLUSIONS: VVI and DDD ICD battery longevity matched industry-projected longevity after 5 years of follow-up. Medtronic and Biotronik ICDs appeared to have an earlier battery depletion. Further randomized studies are required to ensure optimal care.


Assuntos
Desfibriladores Implantáveis , Insuficiência Cardíaca , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Falha de Equipamento , Estudos Retrospectivos , Estudos Prospectivos , Estudos Transversais , Desenho de Equipamento , Estimativa de Kaplan-Meier , Fatores de Tempo , Remoção de Dispositivo
13.
J Contemp Dent Pract ; 24(5): 337-341, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38149812

RESUMO

AIM: This in vitro study aimed to compare and evaluate the resistance to cyclic fatigue of a newly developed glide path file in a simulated double curvature canal in a cyclic fatigue-testing machine. METHODS: In this in vitro study, a static cyclic fatigue-testing machine with a simulated double curve was created and the samples were divided into the following three groups: Group I-HyFlex EDM; group II-TruNatomy file; and group III-Aurum G files and each instrument is continued to rotate in the canal and a number of cycles to failure (NCF) was calculated and Fractographic analysis was done using scanning electron microscope (SEM), and the results were statistically analyzed. RESULTS: Statistical analysis was done using parametric methods one-way analysis of variance (ANOVA) shows statistical significance between groups and then Tukey's HSD post hoc tests were used for multiple pairwise comparisons. TruNatomy glide path files had the highest cyclic fatigue resistance when compared to HyFlex EDM and Aurum G files. CONCLUSION: The selection of file systems in cleaning and shaping protocols is an enigma to endodontics. From the results of this study, it can be concluded that TruNatomy files had higher cyclic fatigue resistance than other glide path files are canals with double curvature, hence it is suitable for usage in root canals with extreme curvature. CLINICAL SIGNIFICANCE: The selection of file systems in cleaning and shaping protocols is an enigma to endodontics. This in vitro study explored the selection protocols for the execution of root canal preparation. Heat treatment of nickel-titanium (NiTi) endodontic files had improved the cyclic fatigue resistance significantly enhancing the clinical life of file systems.


Assuntos
Projetos de Pesquisa , Titânio , Preparo de Canal Radicular , Instrumentos Odontológicos , Falha de Equipamento
14.
J Contemp Dent Pract ; 24(9): 715-721, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38152947

RESUMO

AIM: This research was carried out with the objective of comparison between GenEndo, Protaper Gold, Hero Gold and EdgeFile X3 regarding the effect of different concentrations of NaOCl. MATERIALS AND METHODS: About 720 study specimens were included in the study. They were divided into four groups. Each group consisted of 180 files. Group A: GenEndo, Group B: Protaper Gold, Group C: Hero Gold, Group D: EdgeFile X3. Each group of instruments were further subdivided into nine subgroups (n = 20 for each subgroup). Testing of the cyclic fatigue was carried out in artificial canals which were prepared inside the blocks of stainless steel. The stainless steel blocks with artificial canals were established in a receiver that was packed with experimental solutions like distilled water, 5.25% NaOCl and 2.5% NaOCl. The adjustment of temperature was done at 25, 37, and 60°C. The rotation of the instrument was carried out inside the artificial canal as per the instructions of the manufacturer. The instrument was rotated until it got fractured. The time taken by the instrument to fracture was recorded in seconds. The number of cycles to fracture (NCF) was analyzed with the help of the equation (NCF = time to fracture × rpm/60). Surfaces at the site of fracture were examined with the help of a scanning electron microscope (EVOLS10, ZEISS) at magnification (300x and 2000x). RESULTS: It was noticed that there was a statistically significant increase in cyclic fatigue when sodium chloride was used as an endodontic irrigant instead of distilled water. The increase in cyclic fatigue was also observed when 5.25% sodium chloride was used instead of 2.5% sodium hypochlorite. Cyclic fatigue increased on change in temperature from 25 to 37°C and from 37 to 60°C. The difference was statistically significant (p < 0.05). It was observed that resistance against cyclic fatigue on treatment with different irrigation solutions at different temperatures was in the order of GenEndo > Protaper Gold > Hero Gold > EdgeFile X3. CONCLUSION: The resistance against cyclic fatigue in new NiTi rotary files can be affected significantly by different concentrations of sodium hypochlorite irrigant solution and the GenEndo rotary endodontic instrument has the maximum resistance against cyclic fatigue. CLINICAL SIGNIFICANCE: Irrigation of the root canal with irrigants, such as sodium hypochlorite (NaOCl) has been recommended strongly. NaOCl is used in the range of 0.5 and 6.5% concentration owing to its antimicrobial activity and tissue dissolution activities, particularly at higher temperatures. It has been postulated that fatigue of rotary endodontic instruments can be influenced by adjoining medium and their concentration.


Assuntos
Instrumentos Odontológicos , Falha de Equipamento , Teste de Materiais , Preparo de Canal Radicular , Cloreto de Sódio , Hipoclorito de Sódio , Aço Inoxidável , Temperatura , Titânio , Água
15.
Sci Rep ; 13(1): 22956, 2023 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-38151487

RESUMO

This study aimed to evaluate the effect of the number of uses and autoclave sterilization on the cyclic fatigue resistance of four replica-like instruments RC Blue; Only One File Blue; Recip One Blue; and Micro Blue compared to the original system Reciproc Blue (VDW, Munich, Germany). The instruments were analyzed by scanning electron microscope (SEM) before being used in root canal instrumentation (baseline). Fifty molars were instrumented by ten instruments (n=10). After sterilization in an autoclave, the  instruments were analyzed by SEM. This procedure was repeated twice more using different molars, totaling 3 rounds of instrumentation, sterilization and SEM analysis. Then, ten different instruments from each brand were tested for cyclic fatigue resistance. Number of uses data were analyzed using Chi-squared analysis, and cyclic fatigue data were analyzed by one-way Anova followed by Tukey's test as the data had normal distribution. The fracture times for all systems had no significant difference, but Micro Blue had significantly lower values than the other systems (p < 0.05). The SEM analysis showed distortions in the instruments after the 3rd use. Therefore, all tested instruments except of Micro Blue have similar resistance to cyclic fatigue, and all are reliable for use in up to 2-cases.


Assuntos
Preparo de Canal Radicular , Esterilização , Falha de Equipamento , Estresse Mecânico , Teste de Materiais , Desenho de Equipamento , Titânio
16.
Europace ; 25(12)2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38000900

RESUMO

AIMS: Single-connector (DF4) defibrillator leads have become the predominantly implanted transvenous implantable cardioverter-defibrillator lead. However, data on their long-term performance are derived predominantly from manufacturer product performance reports. METHODS AND RESULTS: We reviewed medical records in 5289 patients with DF4 leads between 2011 and 2023 to determine the frequency of lead-related abnormalities. We defined malfunction as any single or combination of electrical abnormalities requiring revision including a sudden increase (≥2×) in stimulation threshold, a discrete jump in high-voltage impedance, or sensing of non-physiologic intervals or noise. We documented time to failure, predictors of failure, and management strategies. Mean follow-up after implant was 4.15 ± 3.6 years (median = 3.63), with 37% of leads followed for >5 years. A total of 80 (1.5%) leads demonstrated electrical abnormalities requiring revision with an average time to failure of 4 ± 2.8 years (median = 3.5). Of the leads that malfunctioned, 62/80 (78%) were extracted and replaced with a new lead and in the other 18 cases, malfunctioned DF4 leads were abandoned, and a new lead implanted. In multivariable models, younger age at implant (OR 1.03 per year; P < 0.001) and the presence of Abbott/St. Jude leads increased the risk of malfunction. CONCLUSION: DF4 defibrillator leads demonstrate excellent longevity with >98.3% of leads followed for at least 5 years still functioning normally. Younger age at implant and lead manufacturer are associated with an increased risk of DF4 lead malfunction. The differences in lead survival between manufacturers require further investigation.


Assuntos
Desfibriladores Implantáveis , Humanos , Desfibriladores Implantáveis/efeitos adversos , Falha de Equipamento , Estudos Retrospectivos
17.
BMC Oral Health ; 23(1): 825, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37904159

RESUMO

BACKGROUND: The aim of this study was to evaluate the phase composition, phase transformation temperatures, bending property, and cyclic fatigue resistance of different heat-treated nickel-titanium (NiTi) rotary instruments with the same tip diameter and taper at room (RT; 25 ± 1 °C) and body (BT; 37 ± 1 °C) temperatures. METHODS: Five heat-treated NiTi rotary instruments, HyFlex EDM (EDM), HyFlex CM (CM), Vortex Blue (VB), RE file CT (RE) and JIZAI, and a non-heat-treated NiTi rotary instrument (Mtwo) with a size 40, 0.04 taper were investigated. Temperature-dependent phase transformation was examined with differential scanning calorimetry (DSC). The bending loads of the instruments at RT and BT were evaluated using a cantilever-bending test. Cyclic fatigue resistance at RT and BT was measured using a dynamic test, during which the instruments were rotated in combination with a 2-mm back-and-forth motion in an artificial curved canal, and the number of cycles to failure (NCF) was determined. The results were analyzed using two-way repeated measures analysis of variance, a simple main effect test, and the Bonferroni test (α = 0.05). RESULTS: DSC results indicated that EDM and Mtwo were primarily composed of martensite/R-phase and austenite, respectively, while the other heat-treated instruments were composed of a mix of martensite/R-phase and austenite at the tested temperatures. Regardless of the temperature setting, the bending loads of heat-treated instruments were significantly lower than those of Mtwo (p < 0.05). EDM showed the lowest bending loads and highest NCF at both temperatures (p < 0.05). CM, VB, and JIZAI showed significantly higher bending loads at BT than at RT (p < 0.05). The NCF of all the heat-treated instruments, except VB, was lower at BT than at RT (p < 0.05). At BT, the NCF of CM, VB, RE, and JIZAI were not significantly higher than that of Mtwo (p > 0.05). CONCLUSIONS: Heat-treated NiTi instruments exhibited lower bending loads and higher NCF values than Mtwo. However, this tendency was less pronounced at BT than at RT, especially in the NCF values of instruments with a mixture of martensite/R-phase and austenite phases at the tested temperatures.


Assuntos
Temperatura Alta , Titânio , Humanos , Titânio/química , Níquel/química , Temperatura Corporal , Falha de Equipamento , Ligas Dentárias/química , Teste de Materiais , Instrumentos Odontológicos , Preparo de Canal Radicular , Estresse Mecânico
18.
J Hosp Med ; 18(11): 994-998, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37811956

RESUMO

Alarm fatigue (and resultant alarm nonresponse) threatens the safety of hospitalized patients. Historically threats to patient safety, including alarm fatigue, have been evaluated using a Safety I perspective analyzing rare events such as failure to respond to patients' critical alarms. Safety II approaches call for learning from the everyday adaptations clinicians make to keep patients safe. To identify such sources of resilience in alarm systems, we conducted 59 in situ simulations of a critical hypoxemic-event alarm in medical/surgical and intensive care units at a tertiary care pediatric hospital between December 2019 and May 2022. Response timing, observations of the environment, and postsimulation debrief interviews were captured. Four primary means of successful alarm responses were mapped to domains of Systems Engineering Initiative for Patient Safety framework to inform alarm system design and improvement.


Assuntos
Alarmes Clínicos , Humanos , Criança , Unidades de Terapia Intensiva , Segurança do Paciente , Falha de Equipamento , Monitorização Fisiológica
19.
Clin Oral Investig ; 27(11): 6291-6319, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37704917

RESUMO

OBJECTIVE: This systematic review/meta-analysis investigated the influence of NaOCl on cyclic fatigue resistance of endodontic NiTi instruments. MATERIALS AND METHODS: A systematic search until July 2022 in PubMed/MEDLINE, Embase, Scopus, Web of Science, SciELO, Cochrane Library, and grey literature was conducted. According to the PECOS strategy, only in vitro studies evaluating the effects of NaOCl on the cyclic fatigue resistance of NiTi instruments were eligible. Cyclic fatigue resistance was the primary outcome. A modified Joanna Briggs Institute's Checklist was used for risk of bias assessment. RESULTS: Of the 2,445 records screened, 37 studies were included. Most studies used simulated canals made of stainless-steel block with severe to moderate curvatures. NaOCl concentration varied from 1-6%, mainly at 37 °C. Regarding fatigue resistance, 23 studies using 1.2% to 6% NaOCl showed a reduction in the resistance compared to the control groups, especially when pre-heated. Four meta-analyses were performed according to the tested NiTi systems. The meta-analyses indicated that the PTU F2 files had higher reduction of fatigue resistance after exposure to 5.25% NaOCl; no differences between NaOCl and no immersion were observed for Reciproc R25, WaveOne 25.08, and WaveOne Gold Primary files. Included studies had low risk of bias. CONCLUSION: NaOCl appears to reduce cyclic fatigue resistance of certain NiTi files, especially when they are pre-heated, particularly in conventional NiTi files compared to some heat-treated instruments. It is possible that the temperature of the solution may have a greater influence on resistance than NaOCl itself. Important to note that an overall tendency toward no significant influence was observed among various systems. CLINICAL RELEVANCE: Precautions are necessary when a pre-heated high-concentration NaOCl is used to enhance its properties during root canal preparation, mainly using conventional wire.


Assuntos
Níquel , Hipoclorito de Sódio , Titânio , Preparo de Canal Radicular , Falha de Equipamento , Instrumentos Odontológicos , Desenho de Equipamento , Teste de Materiais
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