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BackgroundWhile studies have demonstrated favorable outcomes in utilization of primary total shoulder arthroplasty (TSA) for the treatment of glenohumeral osteoarthritis (OA), adverse events such as infections can still occur. Periprosthetic joint infections (PJIs) are associated with worse outcomes and patient morbidity. The purpose of this study was to: (1) compare patient demographics amongst TSA patients with and without PJIs following primary TSA; and (2) identify patient-related risk factors for PJIs following primary TSA.MethodsPatients undergoing primary TSA for the treatment of glenohumeral OA were identified using the Mariner administrative claims database by CPT code 23,472. Laterality modifiers were utilized to ensure PJIs were developing in the correct laterality as those patients undergoing primary TSA. Inclusion for the study group consisted of patients who developed PJIs within 2-years after the index procedure, whereas patients who did not develop PJIs served as the comparison cohort. Primary outcomes analyzed included patient demographics and patient-related risk factors for PJIs following primary TSA. A stepwise backwards elimination multivariate binomial logistic regression analyses was performed to determine the odds (OR) of PJIs in patients undergoing primary TSA. A P value less than .05 was considered statistically significant.ResultsThe query yielded 15,396 patients who underwent primary TSA for glenohumeral OA, of which 191 patients developed PJIs and 15,205 did not develop PJIs. The study found statistically significant differences amongst patients who did and did not develop PJIs following primary TSA with respect to age, sex, and presence of comorbid conditions. Risk factors associated with developing PJIs following primary TSA included: pathologic weight loss (OR: 2.06, P < .0001), obesity (OR: 1.56, P = .0001), male sex (OR: 1.52, P = .007), and peripheral vascular disease (OR: 1.46, P = .022).ConclusionAs the number of primary TSAs for the treatment of glenohumeral OA increase worldwide, identifying modifiable risk-factors to reduce the incidence of infection is critical. The study found various modifiable and non-modifiable risk factors associated with developing PJIs following primary TSA. This study is valuable to orthopedists in order to identify and risk-stratify patients with regard to PJI in the setting of primary TSA for OA.Level of EvidenceLevel III; Case-Control Study  相似文献   
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Adolescent smoking is a major public health problem. While the socioeconomic status (SES) of the neighbourhood and that of the family are known to play a role in smoking onset and progression, it is not clear whether it modifies the association between parental influences and adolescent behaviour. The purpose of this study is to investigate family correlates of adolescent smoking experimentation and to explore the modifying role of socioeconomic context and European geographical area in a sample of European adolescents. This is a secondary analysis of the baseline survey of the European Drug Addiction Prevention (EU-Dap) trial which took place in seven European countries and involved 7079 students. School SES was used as indicator of socioeconomic context. European countries were aggregated in two geographical areas: North-Central and South. The associations between parental, family factors, and adolescents smoking experimentation were analysed through multilevel mixed-effect logistic regression models, stratified by school SES and European geographical area. Parental smoking, permissiveness towards tobacco, family conflicts, problematic relationships, low connectedness, and low parental control were significantly associated with adolescent smoking experimentation. Paternal smoking was a stronger correlate of adolescent smoking in low SES schools, while maternal smoking in high SES schools. Parental permissiveness was a stronger correlate in low SES schools. Family conflicts and low parental control were correlates only in low SES schools. The associations did not substantially differ between European geographical areas, with the exception of parental smoking that was a stronger correlate in the North, and parental control that was a correlate only in the South of Europe. To reduce inequalities in tobacco-related outcomes, prevention efforts in low socioeconomic contexts appear to be a public health priority. Parental smoking, permissiveness, family relationships, and connectedness should be addressed in preventive programs.

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Motion is a major confound in diffusion‐weighted imaging (DWI) in the body, and it is a common cause of image artefacts. The effects are particularly severe in cardiac applications, due to the nonrigid cyclical deformation of the myocardium. Spin echo‐based DWI commonly employs gradient moment‐nulling techniques to desensitise the acquisition to velocity and acceleration, ie, nulling gradient moments up to the 2nd order (M2‐nulled). However, current M2‐nulled DWI scans are limited to encode diffusion along a single direction at a time. We propose a method for designing b‐tensors of arbitrary shapes, including planar, spherical, prolate and oblate tensors, while nulling gradient moments up to the 2nd order and beyond. The design strategy comprises initialising the diffusion encoding gradients in two encoding blocks about the refocusing pulse, followed by appropriate scaling and rotation, which further enables nulling undesired effects of concomitant gradients. Proof‐of‐concept assessment of in vivo mean diffusivity (MD) was performed using linear and spherical tensor encoding (LTE and STE, respectively) in the hearts of five healthy volunteers. The results of the M2‐nulled STE showed that (a) the sequence was robust to cardiac motion, and (b) MD was higher than that acquired using standard M2‐nulled LTE, where diffusion‐weighting was applied in three orthogonal directions, which may be attributed to the presence of restricted diffusion and microscopic diffusion anisotropy. Provided adequate signal‐to‐noise ratio, STE could significantly shorten estimation of MD compared with the conventional LTE approach. Importantly, our theoretical analysis and the proposed gradient waveform design may be useful in microstructure imaging beyond diffusion tensor imaging where the effects of motion must be suppressed.  相似文献   
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The aim of this study was to evaluate, ex vivo, the histological effects of 445-nm diode laser (Eltech K-Laser srl, Treviso, Italy), during an oral soft ti  相似文献   
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Objectives: (a) To evaluate retrospectively the clinical outcome of non‐vascularized bone grafts used for the reconstruction of mandibular defects following tumor resection; (b) to evaluate the clinical outcome of implants and implant‐supported prostheses placed in the reconstructed areas; and (c) to evaluate patients' satisfaction regarding function and esthetics after oral rehabilitation. Material and methods: In a 9‐year period (1995–2003), 29 patients affected by mandibular tumors involving to tooth bearing areas were treated by means of tumor resection and immediate or delayed reconstruction with autogenous non‐revascularized calvarial or iliac bone grafts. Among these patients, 16 patients were selected for dental rehabilitation of the lost dentition with implant‐supported 3fixed prosthese333s. For to 7 months later, the patients received 60 oral implants for the prosthetic rehabilitation of the reconstructed edentulous areas. Results: No total failure of the graft was observed, while partial loss of the graft was observed in one patient. The mean follow‐up of patients after the start of prosthetic loading of implants treated was 94 months (range: 36–132 months). Two patients dropped out of the follow‐up after 3 and 4 years of observation, respectively. Two implants were removed due to loss of osseointegration, while two implants, although still integrated, presented peri‐implant bone resorption values higher than those proposed by Albrektsson et al. for successful implants. Cumulative survival and success rates of implants were 96.7% and 93.3%, respectively. Conclusion: Results from this study demonstrated that bone defects following resection of mandibular tumors can be predictably reconstructed with autogenous bone grafts taken from the calvarium or the anterior iliac crest. It has also been shown that the long‐term survival and success rates of implants placed in the reconstructed areas (96.7% and 93.3%, respectively) may guarantee an excellent prognosis of implant‐supported prostheses.  相似文献   
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The purpose of the study was to evaluate the shear bond strength of stainless steel orthodontic brackets directly bonded to extracted human premolar teeth. Fifty teeth were randomly divided into five groups: (1) System One (chemically cured composite resin), (2) Light Bond (light-cured composite resin), (3) Vivaglass Cem (self-curing glass ionomer cement), (4) Fuji Ortho LC (light-cured glass ionomer cement) used after 37% orthophosphoric acid-etching of enamel (5) Fuji Ortho LC without orthophosphoric acid-etching. The brackets were placed on the buccal and lingual surfaces of each tooth, and the specimens were stored in distilled water (24 hours) at 37 degrees C and thermocycled. Teeth were mounted on acrylic block frames, and brackets were debonded using an Instron machine. Shear bond strength values at fracture (Nw) were recorded. ANOVA and Student-Newman-Keuls multiple comparison tests were performed (P < .05). Bonding failure site was recorded by stereomicroscope and analyzed by Chi-square test, selected specimens of each group were observed by scanning electron microscope. System One attained the highest bond strength. Light Bond and Fuji Ortho LC, when using an acid-etching technique, obtained bond strengths that were within the range of estimated bond strength values for successful clinical bonding. Fuji Ortho LC and Vivaglass Cem left an almost clean enamel surface after debracketing.  相似文献   
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This study examined the opportunities offered by intraoral distraction osteogenesis to vertically elongate insufficient alveolar ridges and thereby improve local anatomy for ideal implant placement. Eight patients presenting with vertically deficient edentulous ridges were treated by means of the distraction osteogenesis principle with an intraoral alveolar distractor. Two to 3 months after consolidation of the distracted segments, 26 implants were placed in the distracted areas. Four to 6 months later, abutments were connected and prosthetic loading of the implants was started. The mean follow-up after initial prosthetic loading was 14 months. In all patients, the desired bone gain was reached at the end of distraction (mean vertical bone gain of 8.5 mm). Probing depth, Bleeding Index, and Plaque Index around implants were evaluated, and Periotest values were also calculated. The cumulative success rate of implants was 100%. Radiographic examinations 12 months after functional loading of implants showed a significant increase in the density of the newly generated bone in the distracted areas. This technique seems to be reliable, and the regenerated bone has withstood the functional demands of implant loading. Success rates of implants, periodontal indices of peri-implant soft tissues, and Periotest values were consistent with those reported in the literature regarding implants placed in native bone.  相似文献   
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