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41.
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This paper presents a review of the rationale for the in vitro mineralization process, preparation methods, and clinical applications of mineralized collagen. The rationale for natural mineralized collagen and the related mineralization process has been investigated for decades. Based on the understanding of natural mineralized collagen and its formation process, many attempts have been made to prepare biomimetic materials that resemble natural mineralized collagen in both composition and structure. To date, a number of bone substitute materials have been developed based on the principles of mineralized collagen, and some of them have been commercialized and approved by regulatory agencies. The clinical outcomes of mineralized collagen are of significance to advance the evaluation and improvement of related medical device products. Some representative clinical cases have been reported, and there are more clinical applications and long-term follow-ups that currently being performed by many research groups.  相似文献   
43.
Prosthetic heart valve (PHV) dysfunction is a rare but serious complication whose optimal management may be challenging and requires a multidisciplinary approach. Treatment success ultimately depends on determining the underlying mechanism of valve dysfunction by echocardiography. However, being able to establish the main etiology is not always straightforward. We present a difficult case of obstructive PHV dysfunction and discuss clinical and echocardiographic parameters to help differentiate thrombus from pannus formation.  相似文献   
44.
In recent years, scientists have defined two main paths for orthopedic implant fabrication: searching for new materials with properties closest to natural bone in order to reduce the stress-shielding effect or creating individually adapted geometry of the implant with the use and Rapid Prototyping methods. Therefore, materials such as PEEK GRF30 and Ti6Al4V selective laser melting (SLM) are of interest. They are defined as materials suitable for implants, however, the knowledge of their bioactivity, a feature which is one of the most desirable properties of biomaterials, is still insufficient. Using Simulated Body Fluid and Hank’s Balanced Salt Solution, the bioactivity of PEEK GRF30 and Ti6Al4V SLM was assessed, as well as commercial Ti6Al4V as a reference material. Ten cylindrical samples of each material were prepared and immersed in solutions per period from 2 to 28 days at 37 °C. Optical analysis of the changes on the examined surfaces suggested that right after 2-day crystals with different morphologies were formed on each material. Further analysis of the chemical composition of the altered surfaces confirmed the formation of a calcium phosphate layer on them, however, the Ca/P ratio was slightly different from 1.67. On the basis of the obtained results, it can be concluded that both PEEK GRF30 and Ti6Al4V SLM are characterized by appropriate—comparable to Ti6Al4V—bioactivity.  相似文献   
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IntroductionThe conventional evaluation of neural telemetry and impedance requires the use of the computer coupled to an interface, with software that provides visualization of the stimulus and response. Recently, a remote control (CR220®) was launched in the market, that allows the performance of intraoperative tests with minimal instrumentation.ObjectiveTo evaluate the agreement of the impedance values and neural telemetry thresholds, and the time of performance in the conventional procedure and by the remote control.MethodsMulticentric prospective cross-sectional study. Intraoperative evaluations of cochlear implants compatible with the use of CR220® were included. The tests were carried out in the 22 electrodes to compare the time of performance in the two situations. The agreement of the neural telemetry threshold values obtained from five electrodes was analyzed, and the agreement of impedance was evaluated by the number of electrodes with altered values in each procedure.ResultsThere were no significant difference between the impedance values. There was a moderate to strong correlation between the electrically-evoked compound action potential thresholds. The mean time to perform the procedures using the CR220 was significantly lower than that with the conventional procedure.ConclusionThe use of the CR220 provided successful records for impedance telemetry and automatic neural response telemetry.  相似文献   
47.
BackgroundThe aim of this study was to estimate the prevalence of dental prosthetic treatment and to investigate the demographic, social, economic and medical factors associated with the use of fixed and removable dentures in a representative sample of adults living in France.MethodsThe data were obtained from the 2002–2003 Decennial Health Survey, a cross-sectional study of a representative sample of the population living in France, which included 29,679 adults. Information was collected by interview. The variables collected were fixed denture, removable denture, age, gender, number of children, area of residence, nationality, educational attainment, family social status, employment status, annual household income per capita, supplementary insurance, chronic disease, eyesight problems/glasses, hearing problems/hearing aids. Multinomial logistic regression models were used to study the relationship between prosthetic treatment and demographic, socioeconomic and medical characteristics unadjusted, adjusted for age and adjusted for all the characteristics.ResultsThe prevalence of prosthetic treatment was 34.6% (95% confidence interval (CI): [34.1; 35.2]) for fixed prosthetic dentures and 13.8% (95% CI: [13.4; 14.2]) for removable prosthetic dentures. We showed a gradient between educational attainment and removable dentures; the odds ratio adjusted for all the variables (aOR) associated with no or primary education compared to post-secondary education was 2.56; 95% CI: [2.09; 3.13]. When annual household income per capita was low, subjects were less likely to report fixed dentures (aOR = 0.68; 95% CI: [0.62; 0.75]) than those with high annual household income per capita. Individuals without insurance less often reported fixed dentures than those with private insurance. Those reporting chronic disease were less likely to report fixed dentures (aOR = 0.87; 95% CI: [0.79; 0.95]) but more likely to report removable dentures (aOR = 1.29; 95% CI: [1.17; 1.43]) than those without chronic disease.ConclusionThis study reveals social, economic and medical inequalities in fixed and removable prosthetic treatment among adults in France.  相似文献   
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The aim of this study was to assess the clinical and microbiological parameters around dental zirconia and titanium implants compared with natural teeth during experimental plaque accumulation. Clinical parameters were evaluated (gingival index, plaque index, bleeding on probing, and probing pocket depth). Microbiological samples were analyzed for total bacterial cell counts, as well as Tannerella forsythia and Prevotella intermedia counts. A statistically significant difference over time was observed in the groups in terms of the gingival index (P < 0.001), plaque index (P < 0.001), and bleeding on probing (P = 0.039). The lowest mean total number of bacterial cells was measured around the teeth, followed by the zirconia implants; the highest values were found around the titanium implants. T. forsythia and P. intermedia values showed significant changes over time and sessions around the titanium implants. Compared to the soft tissues around zirconia implants and the teeth, those around titanium implants developed a stronger inflammatory response to experimental plaque accumulation in terms of the total number of bacterial cells and T. forsythia and P. intermedia values.  相似文献   
50.
Our aim was to evaluate neurosensory symptoms after lateralisation of the inferior alveolar nerve (IAN). We studied a retrospective case series with one-year follow up that included 139 procedures in 123 patients. After the IAN had been located it was deflected from the mandibular body and the implant placed. Sensitivity was mapped 24 hours, one month, six months, and one year after the intervention by gently pressing the skin and lips with the tip of a probe. A total of 337 implants were placed in 123 patients aged between 44 and 68 years.There were 33 men and 90 women and they all recovered. The IAN was mobilised by one of two procedures, one that involves the nerve directly (transposition) and one that does not (lateralisation). During lateralisation the nerve is deflected laterally through a mandibular osteotomy, while the mental nerve and mental foramen are not manipulated. The resulting hypoaesthetic area was drawn on a graph to assess its extension. Although different techniques are available for placing implants in atrophic jaws, mobilisation of the IAN is indicated in certain cases in which other techniques are not feasible or have a high risk of complications.  相似文献   
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