RESUMEN
A significant swelling was seen in the floor of the mouth of a newborn girl. The girl could only drink with difficulty. On examination, a soft-elastic swelling was seen beneath the tongue. Ultrasonography and MRI showed a mass located above the hyoid bone. Upon the initial differential diagnosis of a dermoid cyst, an enucleation of the lesion was performed. Histopathological examination suggested a branchiogenic cyst or a digestive duplication cyst. Given the inconclusiveness of additional diagnostic examination, the lesion was diagnosed as a developmental cyst. Six months after enucleation, the infant girl's tongue motility was not restricted and there were no indications of a recurrence. This rare case illustrates the variety in differential diagnosis and the limitations of additional diagnostic examination.
Asunto(s)
Quiste Dermoide , Neoplasias de la Boca , Femenino , Humanos , Recién Nacido , Quiste Dermoide/diagnóstico , Quiste Dermoide/cirugía , Quiste Dermoide/patología , Diagnóstico Diferencial , Suelo de la Boca/patología , Lengua/patologíaRESUMEN
The aim of this study was to compare the effects of maxillomandibular advancement (MMA) on respiratory function between obstructive sleep apnoea (OSA) patients with and without maxillomandibular deficiency, and to compare the changes in facial aesthetics after MMA between the two groups. MMA-treated patients who had both baseline and follow-up polysomnography (PSG) data and lateral cephalograms were enrolled in this retrospective study. In addition to PSG and cephalometric data, patient satisfaction with postoperative breathing and facial aesthetics, and overall satisfaction with the treatment were assessed. Twenty-one patients were classified as not having maxillomandibular deficiency (without-deficiency group) and 40 patients as having maxillomandibular deficiency (with-deficiency group). The improvements in respiratory parameters (e.g., apnoea-hypopnoea index) and patient satisfaction with postoperative breathing were comparable in the two groups (P = 0.094-0.713). The changes in facial profile measurements (e.g., nasal prominence, nasolabial angel, and lip positions relative to the true vertical line) and patient satisfaction with postoperative facial aesthetics were also comparable in the two groups (P = 0.148-0.983). In conclusion, no significant difference in the effects of MMA on respiratory function and facial aesthetics between OSA patients with and without maxillomandibular deficiency was observed.
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Avance Mandibular , Apnea Obstructiva del Sueño , Humanos , Maxilar/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Apnea Obstructiva del Sueño/cirugía , EstéticaRESUMEN
A 49-year-old woman who suffered from severe obstructive sleep apnea (OSA) was referred to the department of Oral-, Maxillofacial Surgery department due to progressive limitation of the mouth opening and chronic pain in both temporomandibular joints. Based on clinical and radiological examinations, the patient was diagnosed with recurrent ankylosis of the temporomandibular joints. The patient was treated with 2 patient-specific implants of the temporomandibular joint combined with a Le Fort I osteotomy, and a genioplasty including a genioglossus advancement. This treatment may have advantages for the patient such as a lower recurrence rate of ankylosis, improved maximal mouth opening, pain reduction and improved aesthetic results.
Asunto(s)
Apnea Obstructiva del Sueño , Trastornos de la Articulación Temporomandibular , Anquilosis del Diente , Femenino , Humanos , Persona de Mediana Edad , Osteotomía , Articulación Temporomandibular/cirugía , Trastornos de la Articulación Temporomandibular/diagnóstico , Trastornos de la Articulación Temporomandibular/cirugíaRESUMEN
The aim of this study was to compare two techniques for temporary intraoperative maxillomandibular fixation (TIO-MMF) during orthognathic surgery: steel-wire ligatures versus power chains. Patients undergoing orthognathic surgery between October 2019 and March 2020 were included in a prospective cross-sectional study conducted in three participating hospitals. Data were collected using a standardized measurement form. A total of 44 patients were included, in whom TIO-MMF was applied 79 times. A statistically significant difference in intraoperative loss of stability of the segment relationship was found between steel-wire ligatures (11.4%) and power chains (0%). The mean application time of TIO-MMF differed significantly between steel-wire ligatures (99 seconds) and power chains (157 seconds) (P < 0.001). There was no statistical difference in occurrence of adverse events between the two techniques. This study found that the application of TIO-MMF with power chains is more stable compared to steel-wire ligatures. Steel-wire ligatures were significantly faster to apply, although the absolute difference (less than 1 minute) was small. Other possible advantages of the proposed technique are discussed. The results of this study suggest that power chains for the application of TIO-MMF in orthognathic surgery are a valuable alternative to steel-wire ligatures.
Asunto(s)
Implantes Dentales , Técnicas de Fijación de Maxilares , Estudios Transversales , Humanos , Proyectos Piloto , Estudios Prospectivos , AceroRESUMEN
Obstructive sleep apnea (OSA) on its own, as well as its risk factors, have been found to be associated with the outcome of Coronavirus disease 2019 (COVID-19). However, the association between the degree of OSA and COVID-19 severity is unclear. Therefore, the aim of the study was to evaluate whether or not parameters to clinically evaluate OSA severity and the type of OSA treatment are associated with COVID-19 severity. Patient data from OSA patients diagnosed with COVID-19 were reviewed from outpatients from the Isala Hospital and patients admitted to the Isala Hospital, starting from March until December 2020. Baseline patient data, sleep study parameters, OSA treatment information and hospital admission data were collected. Apnea hypopnea index (AHI), low oxyhemoglobin desaturation (LSAT), oxygen desaturation index (ODI), respiratory disturbance index (RDI), and the type of OSA treatment were regarded as the independent variables. COVID-19 severity-based on hospital or intensive care unit (ICU) admission, the number of days of hospitalization, and number of intubation and mechanical ventilation days-were regarded as the outcome variables. Multinomial regression analysis, binary logistic regression analysis, and zero-inflated negative binomial regression analysis were used to assess the association between the parameters to clinically evaluate OSA severity and COVID-19 severity. A total of 137 patients were included. Only LSAT was found to be significantly associated with the COVID-19 severity (p<0.05) when COVID-19 severity was dichotomized as non-hospitalized or hospitalized and ICU admission or death. Therefore, our findings showed that LSAT seems to be a significant risk factor for COVID-19 severity. However, the degree of OSA-based on AHI, ODI, and RDI-and OSA treatment were not found to be risk factors for COVID-19 severity when looking at hospital or ICU admission, the number of days of hospitalization, and number of intubation and mechanical ventilation days.
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COVID-19/diagnóstico , Unidades de Cuidados Intensivos/estadística & datos numéricos , Índice de Severidad de la Enfermedad , Apnea Obstructiva del Sueño/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/epidemiología , COVID-19/virología , Comorbilidad , Estudios Transversales , Epidemias/prevención & control , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2/fisiología , Apnea Obstructiva del Sueño/epidemiologíaRESUMEN
A 41-year-old woman, who was referred with a reddish purple like lesion on the left side of the tongue, appeared to have an angiokeratoma after histopathological examination. Because of the benign character of this lesion and the absence of any complaints, no adjuvant treatment after excisional biopsy was indicated. Angiokeratomas rarely appear as solitary oral lesions. More often they are seen as part of an underlying systemic disease, mostly Fabry disease. Due to widespread skin involvement of angiokeratomas with Fabry disease, referral to a dermatologist is indicated when oral lesions are encountered. Esthetically unpleasing or painful angiokeratomas can be locally excised or treated by laser- or cryotherapy.
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Angioqueratoma , Neoplasias Cutáneas , Adulto , Angioqueratoma/diagnóstico , Biopsia , Femenino , Humanos , Neoplasias Cutáneas/diagnóstico , LenguaRESUMEN
Sagittal split ramus osteotomy (SSRO) with large mandibular advancements is a common surgical procedure and could be indicated for patients with sleep apnoea. As a large variety of fixation methods is used for the stabilisation of SSRO, a biomechanical test model was used to analyse which fixation technique was most stable. For this in vitro study, 80 polyurethane hemimandibles with a prefabricated SSRO were used as substrates. Loads in Newtons were recorded at displacements of the mandibular incisive edge at 1mm, 3mm and 5mm. The samples were divided into two groups: mandibular advancements of 10mm and 15mm. In both groups, four fixation techniques were used: (A) one four-hole miniplate; (B) two four-hole miniplates; (C) one four-hole miniplate plus one bicortical screw; and (D) three bicortical screws in an inverted-L arrangement. In group 1, three bicortical screws resulted in the best stability, and in group 2, two miniplates resulted in the best stability. The use of two miniplates did not show significant differences between both groups. Other fixation methods showed more stability with 10mm advancements. This study therefore suggests that in SSRO with advancements exceeding 10mm, the use of two miniplates is the optimal means of providing rigid fixation.
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Avance Mandibular , Osteotomía Sagital de Rama Mandibular , Fenómenos Biomecánicos , Placas Óseas , Humanos , Mandíbula/cirugía , Modelos AnatómicosRESUMEN
BACKGROUND: Individuals on anticoagulation therapy are at increased risk of bleeding, including epistaxis. There is a lack of available reversal agents for novel oral anticoagulation therapy. OBJECTIVE: This paper reviews the current literature on epistaxis in the context of novel oral anticoagulation use, in order to recommend guidelines on management. METHOD: A comprehensive search of published literature was conducted to identify all relevant articles published up to April 2019. RESULTS: Patients on oral anticoagulation therapy are over-represented in individuals with epistaxis. Those on novel oral anticoagulation therapy were more likely to relapse compared to patients on classic oral anticoagulants or non-anticoagulated patients. Idarucizumab is an effective antidote for bleeding associated with dabigatran use. Recommendations for epistaxis management in patients on novel oral anticoagulation therapy are outlined. CONCLUSION: Clinicians need to be aware of the potential severity of epistaxis and the increased likelihood of recurrence. High-quality studies are required to determine the efficacy and safety of andexanet alfa and ciraparantag, as well as non-specific reversal agents.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , Antídotos/uso terapéutico , Epistaxis/tratamiento farmacológico , Administración Oral , Anciano , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , Antídotos/administración & dosificación , Antitrombinas/efectos adversos , Antitrombinas/uso terapéutico , Arginina/administración & dosificación , Arginina/análogos & derivados , Arginina/uso terapéutico , Concienciación , Dabigatrán/efectos adversos , Dabigatrán/uso terapéutico , Epistaxis/inducido químicamente , Epistaxis/epidemiología , Factor Xa/administración & dosificación , Factor Xa/uso terapéutico , Inhibidores del Factor Xa/efectos adversos , Inhibidores del Factor Xa/uso terapéutico , Primeros Auxilios/normas , Humanos , Masculino , Piperazinas/administración & dosificación , Piperazinas/uso terapéutico , Prevalencia , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/uso terapéutico , Rivaroxabán/efectos adversos , Rivaroxabán/uso terapéutico , Índice de Severidad de la EnfermedadRESUMEN
The aim of this pilot study was to evaluate the accuracy and predictability of a splintless treatment protocol for edentulous patients undergoing orthognathic surgery in four consecutive cases. All operations were virtually planned, followed by computer-aided design of individual osteotomy guides and patient-specific fixation implants, which were three-dimensionally printed in titanium. In order to evaluate the discrepancy between the planned and the achieved postoperative result, the postoperative outcome was compared to the virtual treatment plan. Rotational and translational movement and discrepancies with the planned movements were quantified for the maxilla; the advancement was quantified for the mandible. For the maxilla, there was a mean translation discrepancy of 0.6mm. With regard to rotation, there was a mean discrepancy of 1.9°, 0.1°, and 0.4° for pitch, yaw, and roll, respectively. The mean discrepancy in translation of the mandible was 0.4mm. The results of this pilot study indicate that the splintless treatment protocol for orthognathic surgery in edentulous patients presented here is accurate and predictable.
Asunto(s)
Implantes Dentales , Cirugía Ortognática , Procedimientos Quirúrgicos Ortognáticos , Cirugía Asistida por Computador , Humanos , Mandíbula , Maxilar , Osteotomía Le Fort , Proyectos PilotoRESUMEN
In orbital reconstruction, the acquired position of an orbital implant can be evaluated with the aid of intraoperative navigation. Feedback of the navigation system is only obtained after positioning of the implant: the implant's position is not tracked in real time during positioning. The surgeon has to interpret the navigation feedback and translate it to desired adjustments of the implant's position. In a previous study, a real-time implant-oriented navigation approach was introduced and the system's accuracy was evaluated. In this study, this real-time navigation approach was compared to a marker-based navigation approach in a preclinical set-up. Ten cadavers (20 orbital defects) were reconstructed twice, by two surgeons (total: 80 reconstructions). Implant positioning was significantly improved in the real-time implant-oriented approach in terms of roll (2.0° vs. 3.2°, P=0.03), yaw (2.2° vs. 3.4°, P=0.01) and translation (1.3mm vs. 1.8mm, P=0.005). Duration of the real-time navigation procedure was reduced (median 4.5 min vs. 7.5 min). Subjective appreciation of the navigation technique was higher for real-time implant-oriented navigation (mean 7.5 vs. 9.0). Real-time implant-oriented navigation feedback provides real-time, intuitive feedback to the surgeon, which leads to improved implant positioning and shortens duration of the navigation procedure.
Asunto(s)
Implantes Dentales , Fracturas Orbitales , Procedimientos de Cirugía Plástica , Cirugía Asistida por Computador , Cadáver , HumanosRESUMEN
OBJECTIVE: Chronic maxillary atelectasis is a rare and underdiagnosed condition in which there is a persistent and progressive decrease in maxillary sinus volume secondary to inward bowing of the antral walls. Chronic maxillary atelectasis is typically unilateral. Simultaneous bilateral chronic maxillary atelectasis is extremely uncommon. METHODS: A retrospective review was performed of patient data collected by the senior clinician over a three-year period (2015-2018). A comprehensive literature search was conducted to locate all documented cases of chronic maxillary atelectasis in English-language literature. Abstracts and full-text articles were reviewed. RESULTS: Three patients presented with sinonasal symptoms. Imaging findings were consistent with bilateral chronic maxillary atelectasis. The literature review revealed at least nine other cases of bilateral chronic maxillary atelectasis. Management is typically via endoscopic middle meatus antrostomy. CONCLUSION: Chronic maxillary atelectasis was initially defined as a unilateral disorder, but this description has been challenged by reports of bilateral cases. Further investigation is required to determine the aetiology and pathophysiology of the disease.
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Seno Maxilar/patología , Enfermedades de los Senos Paranasales/patología , Adulto , Enfermedad Crónica , Humanos , Masculino , Seno Maxilar/diagnóstico por imagen , Persona de Mediana Edad , Enfermedades de los Senos Paranasales/diagnóstico , Enfermedades de los Senos Paranasales/diagnóstico por imagen , Estudios Retrospectivos , Síndrome , Tomografía Computarizada por Rayos XRESUMEN
A 15-year-old boy was referred to an Oral and Maxillofacial Surgery department because of a persistent tooth 85 and a malposition of tooth 45. Following additional examination, it was concluded that the root formation of tooth 45 was already completed. Furthermore, it was horizontally impacted against the inferior border of the mandible. The decision was made to extract tooth 85 and to autotransplant tooth 45. Post-operatively, tooth 45 was fixed to the orthodontic equipment already in place and later treated endodontically. The success rate of this kind of autotransplantation of teeth with already closed apices (94%) is comparable in the literature to the success rate of autotransplantation of teeth with open apices (98%). Autotransplantation should be considered, especially in patients who are still growing and for whom dental implants do not (yet) offer a solution.
Asunto(s)
Diente Impactado/cirugía , Diente/trasplante , Trasplante Autólogo , Adolescente , Humanos , Masculino , Raíz del Diente/cirugía , Resultado del TratamientoRESUMEN
BACKGROUND: Since the introduction of recombinant tissue plasminogen activator (rt-PA) for acute ischemic stroke, rt-PA rate and number of stroke centers have increased. Despite this, studies have shown racial and ethnic disparities in stroke care especially in Black and Hispanic populations. What factors are related to the administration of rt-PA within the Hispanic population has to date been unclear. METHODS: We performed a retrospective review of IRB approved, prospectively collected data from the UC San Diego Stroke Registry from 7/2004-7/2016. Patients were included based on the primary diagnosis of Transient Ischemic Attack or Ischemic Stroke. Hispanic vs non-Hispanic patients were compared to assess for overall rt-PA treatment rates and process of care intervals. For the Hispanic cohort itself, demographics and NIHSS scores were assessed to determine why some Hispanics received rt-PA while others were not. RESULTS: Overall, 1489 patients (300 Hispanic vs. 1189 non-Hispanic) were included. Comparing Hispanics to non-Hispanics, there was no difference in rt-PA rate (35.3% vs. 33.1%; p=0.49). In rt-PA treated patients, "onset to arrival" interval was higher in Hispanics (1.03 vs. 0.88 hours; p=0.04), while the "arrival to treatment" interval was not different (1.13 vs. 1.02 hours; p=0.07). When looking at Hispanic patients only, there was no difference in baseline characteristics except for initial NIHSS in treated vs. non-treated patients (13.27 vs. 7.24; p<.001). CONCLUSION: Our analyses sought to determine the factors important to administration of rt-PA to Hispanic patients. These findings highlight the need for strategies to improve recognition and presentation pathways for Hispanics.
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BACKGROUND: Identification of large vessel occlusions (LVO) is important with recent guidelines supporting endovascular therapy in selected acute ischemic stroke patients. Many stroke centers perform CT angiography (CTA) in patients with suspected LVO, however this requires additional time and contrast administration. Non-enhanced CT maximum intensity projection (NECT-MIPs) may offer a rapid alternative to CTA. METHODS: We retrospectively reviewed acute stroke patients with LVO in the UCSD Stroke Registry, presenting between 6/2014-7/2016. NECT-MIPs were evaluated for presence of LVO. Gold standard comparison was to CTA. Results were stratified by level of training (Faculty, Fellow and Acute Care Practitioners [ACPs]). Inter-rater agreement was assessed using Fleiss' Kappa Coefficient. RESULTS: We reviewed 24 patients using NECT-MIPs for the detection of LVO. Faculty had a sensitivity and specificity of 95% & 92% for ICA/M1, 42% & 100% for M2, and 67% & 96% for basilar occlusions. Fellows and ACPs had a sensitivity and specificity of 61% & 94% for ICA/M1, 19% & 83% for M2, and 75% & 95% for basilar occlusions. Inter-rater agreement among Faculty readers was k=0.75 for ICA/M1, k=0.79 for M2 and k=0.14 for basilar occlusions. Among Fellows and ACPs, k=0.57 for ICA/M1, k=0.40 for M2, and k=0.27 for basilar occlusions. CONCLUSIONS: NECT-MIPs have high sensitivity and specificity for the detection of LVO when compared to CTA. Inter-rater agreement is fair and higher amongst more experienced reviewers. These results suggest that NECT-MIPs may be helpful to streamline the identification of LVO and reduce door to needle and door to intervention times.
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In the 1990s intra-oral distraction osteogenesis (DO) became available as an alternative for bilateral sagittal splitosteotomy (BSSO) for advancement of the mandible. It was thought that DO would lead to more stability in the results and fewer neurosensory disturbances of the inferior alveolar nerve. However, there was no scientific evidence for this assumption. This article describes a number of recently published, prospective studies that demonstrate that BSSO is not inferior to DO with respect to stability and neurosensory disturbances of the inferior alveolar nerve. They also demonstrate that BSSO leads to less pain in patients and to lower total costs. It can be concluded that BSSO should be considered the standard therapy for mandibular advancement up to 10 mm in non-syndromal patients.
Asunto(s)
Avance Mandibular/métodos , Osteogénesis por Distracción , Osteotomía Sagital de Rama Mandibular , Traumatismos del Nervio Craneal/epidemiología , Humanos , Países Bajos , Resultado del TratamientoRESUMEN
PURPOSE: The present study examined the internal responsiveness of the short-form Oral Health Impact Profile (OHIP-14) and its ability to differentiate between patients with and without pre- and postoperative complaints as well as other clinical variables. METHODS: The sample consisted of 97 patients undergoing surgical third molar removal. The OHIP-14 was filled in preoperatively, on each postoperative day for a week and once more after 1 month. In addition, pre- and postoperative status was measured along with other clinical variables. RESULTS: The OHIP-14 is able to differentiate between the first preoperative day (M = 16.85, SD = 5.35) and all the days within the postoperative week (first day M = 29.46, SD = 9.32). One month postoperatively, mean OHIP scores are reduced to preoperative levels. In addition, differences could be shown between patients with and without pre- (M = 18.9, SD = 8.1 vs. M = 16.2, SD = 3.9) and postoperative complaints (M = 18.9, SD = 8.1 vs. M = 16.2, SD = 3.9), partial (preop; M = 17.8, SD = 6.8, postoperative; M = 27.4, SD = 7.7) and complete mucosa coverage (preop; M = 15.9, SD = 3.2, postoperative; M = 29.5, SD = 10.6) and the level of impaction (Pell and Gregory classification) of the third molar (3B showing the highest increase in the mean OHIP score). CONCLUSIONS: The OHIP-14 can be considered internally responsive to changes in impacts of oral conditions as a result of surgical third molar removal and is able to differentiate the effect of several clinical variables.
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Tercer Molar/cirugía , Complicaciones Posoperatorias , Perfil de Impacto de Enfermedad , Extracción Dental , Adulto , Femenino , Estado de Salud , Humanos , Masculino , Salud Bucal , Reproducibilidad de los Resultados , Adulto JovenRESUMEN
Nanophase materials are promising alternative implant materials in tissue engineering. Here we report for the first time the large-scale direct growth of nanostructured bioactive titanates on three-dimensional (3D) microporous Ti-based metal (NiTi and Ti) scaffolds via a facile low temperature hydrothermal treatment. The nanostructured titanates show characteristics of 1D nanobelts/nanowires on a nanoskeleton layer. Besides resembling cancelous bone structure on the micro/macroscale, the 1D nanostructured titanate on the exposed surface is similar to the lowest level of hierarchical organization of collagen and hydroxyapatite. The resulting surface displays superhydrophilicity and favors deposition of hydroxyapatite and accelerates cell attachment and proliferation. The remarkable simplicity of this process makes it widely accessible as an enabling technique for applications from engineering materials treatment including energy-absorption materials and pollution-treatment materials to biotechnology.
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Materiales Biomiméticos/química , Nanoestructuras/química , Nanoestructuras/ultraestructura , Titanio/química , Microscopía Electrónica , Porosidad , Difracción de Rayos XRESUMEN
Porous NiTi shape memory alloys are one of the promising biomaterials for surgical implants because of their unique shape memory effects and porous structure with open pores. However, the complex surface morphology and larger area of porous NiTi compared to dense NiTi make it more vulnerable from the viewpoint of release of nickel, which can cause deleterious effects in the human body. It is also more difficult to modify the exposed surfaces of a porous structure using conventional surface modification technologies. In this work, oxidation in conjunction with postreaction heat treatment was used to modify the surfaces of porous single-phase NiTi prepared by capsule-free hot isostatic pressing to mitigate Ni leaching and enhance the surface properties. Differential scanning calorimetry thermal analysis, uniaxial compression tests, inductively-coupled plasma mass spectrometry, and cell cultures reveal that porous NiTi alloys oxidized at 450 degrees C for 1 h have an austenite transition temperature below 37 degrees C, excellent superelasticity, lower nickel release, and no cytotoxicity.
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Cobre/metabolismo , Níquel/metabolismo , Osteoblastos/citología , Titanio/metabolismo , Aleaciones/metabolismo , Animales , Rastreo Diferencial de Calorimetría , Células Cultivadas , Elasticidad , Ratones , Oxidación-Reducción , Porosidad , Análisis Espectral , Propiedades de Superficie , Temperatura , Difracción de Rayos XRESUMEN
Good surface properties and biocompatibility are crucial to porous NiTi shape memory alloys (SMA) used in medical implants, as possible nickel release from porous NiTi may cause deleterious effects in the human body. In this work, oxygen plasma immersion ion implantation (O-PIII) was used to reduce the amount of nickel leached from porous NiTi alloys with a porosity of 42% prepared by capsule-free hot isostatic pressing. The mechanical properties, surface properties, and biocompatibility were studied by compression tests, X-ray photoelectron spectroscopy (XPS), and cell culturing. The O-PIII porous NiTi SMAs have good mechanical properties and excellent superelasticity, and the amount of nickel leached from the O-PIII porous NiTi is much less than that from the untreated samples. XPS results indicate that a nickel-depleted surface layer predominantly composed of TiO(2) is produced by O-PIII and acts as a barrier against out-diffusion of nickel. The cell culturing tests reveal that both the O-PIII and untreated porous NiTi alloys have good biocompatibility.
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Aleaciones , Materiales Biocompatibles , Níquel , Oxígeno , Titanio , Animales , Animales Recién Nacidos , Células Cultivadas , Ratones , Osteoblastos , PorosidadRESUMEN
Nickel-titanium shape memory alloys are promising materials in orthopedic applications because of their unique properties. However, for prolonged use in a human body, deterioration of the corrosion resistance of the materials becomes a critical issue because of the increasing possibility of deleterious ions released from the substrate to living tissues. We have investigated the use of nitrogen, acetylene, and oxygen plasma immersion ion implantation (PIII) to improve the corrosion resistance and mechanical properties of the materials. Our results reveal that the corrosion resistance and mechanical properties such as hardness and elastic modulus are significantly enhanced after surface treatment. The release of nickel is drastically reduced as compared with the untreated control. In addition, our in vitro tests show that the plasma-treated surfaces are well tolerated by osteoblasts. Among the three types of samples, the best biological effects are observed on the nitrogen PIII samples.