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Objective: In 2013, the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) published guidelines for Bell's palsy (BP), including recommendations for workup, management, and specialist referral. Patients with BP often present to primary care; however, adherence to guidelines may vary by setting. This study sought to evaluate the management of patients with BP presenting to primary care, emergency department (ED), and urgent care settings., Study Design: Retrospective cohort study., Setting: Tertiary care center., Methods: Retrospective chart review of patients identified by diagnosis code for BP., Results: A total of 903 patients were included; 687 (76.1%) presented to ED, 87 (9.6%) to internal medicine, 77 (8.5%) to family medicine, and 52 (5.8%) to urgent care. On presentation, 804 (89.0%) patients were prescribed corticosteroids and 592 (65.6%) antiviral therapy. Steroid therapy ranged from 1 dose to greater than a 14-day course, with 177 (19.6%) receiving an adequate duration of 10 days or greater. Referrals were provided to facial plastics and/or otolaryngology for 51 patients (5.6%). For all comers, 283 (31.3%) had complete resolution, 197 (21.8%) had an incomplete resolution, 62 (6.9%) had persistent palsy, and 361 (40.0%) lost to follow-up. In assessing the association between clinic setting and management, appropriate corticosteroid therapy (p < .01), imaging (p < .01), and eye care (p < .01) were statistically significant., Conclusion: Adherence to guidelines for BP management varies amongst providers. In our study cohort, 15.5% of patients received medical therapy in accordance with AAO-HNS guidelines, and only 5.6% were referred to facial plastics. To facilitate more appropriate care, tertiary care institutions may benefit from system-wide care pathways to manage acute BP., (© 2023 The Authors. Otolaryngology-Head and Neck Surgery published by Wiley Periodicals LLC on behalf of American Academy of Otolaryngology-Head and Neck Surgery Foundation.)

Purpose: We hypothesized that a pain management prescribing tool embedded in the electronic health record system of a multihospital health care system would decrease prescription opioids for postoperative pain by hand, orthopedic, plastic, and spine surgeons., Methods: A prescribing tool for postoperative pain was designed for hand, orthopedic, plastic, and spine surgeons and implemented into electronic discharge order sets in a 10-hospital health care system. Stakeholders were educated on tool use in person and/or by email on 2 occasions. A dashboard was created to monitor opioid pill quantities and morphine milligram equivalents (MMEs) prescribed. Overall compliance with the suggested opioid amounts was assessed for 20 months after tool implementation. A subgroup of 6 hand surgeons, one of whom was instrumental in designing the tool, were evaluated for MMEs prescribed, opioid refills, patient emergency room visits, and patient readmissions within 30 days after discharge. Comparisons in this subgroup were made from 12 months before to 15 months after tool implementation., Results: The mean system-wide compliance with the suggested opioid pill quantities and MMEs prescribed in all 4 specialties improved by less than 5%. In the subgroup of hand surgeons, 5 of whom championed tool use, prescribed MMEs decreased by 10% during each of the 4 quarters before launching the tool and contracted an additional 26% in the first quarter after tool implementation. Opioid refills held steady at 5%, and there were no emergency room visits or readmissions within 30 days after discharge in this patient subgroup., Conclusions: The prescribing tool had a negligible impact on system-wide compliance with suggested prescription opioid pill quantities and MMEs. In a small group of surgeons who championed the use of the tool, there was a significant and sustained decline in MMEs prescribed without adversely impacting patient refills, emergency room visits, or readmissions., Clinical Relevance: An electronic prescribing tool to assist surgeons in lowering opioid prescription pill quantities and MMEs may have a negligible impact on prescribing behavior in a multihospital health care system., (Copyright © 2022. Published by Elsevier Inc.)

Background: Environmental pollution and male infertility have become global public health problems. The presence of microplastics (MPs) has been detected in the human body, and it has also been demonstrated that MPs can cause damage to the reproductive system. Wuwei Fuzheng Yijing Decoction (WWFZYJ) is effective in treating male infertility. Therefore, we designed a clinical randomized controlled trial to observe the effect of WWFZYJ on the content of MPs and semen quality in male infertility patients, and to evaluate its security., Methods: In this randomized controlled study, 66 eligible patients were randomly assigned in a 1:1 ratio to a treatment group (WWFZYJ Decoction) and a control group (Coenzyme Q10 tablets combined with vitamin E soft capsules) for 8 weeks. The content of MPs in semen, sperm DNA Fragmentation Index (DFI), and semen analysis (including sperm density, sperm count, forward motile sperm, sperm motility, etc) will be used as primary indicators, and Traditional Chinese Medicine (TCM) syndrome scores will be used as secondary indicators. Vital signs (such as respiration, heart rate, body temperature, blood pressure, electrocardiogram, etc), blood routine, urine routine, stool routine, liver function, and renal function will be used as safety indicators. The primary and secondary indicators will be performed at 0th and 8th week, and the safety indicators will be performed at 0th, 4th, and 8th week., Discussion: This study will provide evidence for the efficacy and safety of WWFZYJ in treating male infertility and reducing the content of MPs in semen, and further explore the effects of MPs on male fertility., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)

The application of monoclonal antibodies (mAbs) for the treatment of melanoma has significantly improved the clinical management of this malignancy over the last decade. Currently approved mAbs for melanoma enhance T cell effector immune responses by blocking immune checkpoint molecules PD-L1/PD-1 and CTLA-4. However, more than half of patients do not benefit from treatment. Targeting the prominent myeloid compartment within the tumor microenvironment, and in particular the ever-abundant tumor-associated macrophages (TAMs), may be a promising strategy to complement existing therapies and enhance treatment success. TAMs are a highly diverse and plastic subset of cells whose pro-tumor properties can support melanoma growth, angiogenesis and invasion. Understanding of their diversity, plasticity and multifaceted roles in cancer forms the basis for new promising TAM-centered treatment strategies. There are multiple mechanisms by which macrophages can be targeted with antibodies in a therapeutic setting, including by depletion, inhibition of specific pro-tumor properties, differential polarization to pro-inflammatory states and enhancement of antitumor immune functions. Here, we discuss TAMs in melanoma, their interactions with checkpoint inhibitor antibodies and emerging mAbs targeting different aspects of TAM biology and their potential to be translated to the clinic., Competing Interests: S.N.K. is the founder and shareholder of Epsilogen Ltd. and declares patents on antibody technologies., (© 2022 The Author(s). Published with license by Taylor & Francis Group, LLC.)

Background: Early identification of plastic bronchitis (PB) is of great importance and may aid in delivering appropriate treatment. This study aimed to develop and validate a nomogram for predicting PB in patients with refractory Mycoplasma pneumoniae pneumonia (RMPP)., Methods: A total of 547 consecutive children with RMPP who underwent fiberoptic bronchoscopy (FOB) intervention from January 2016 to June 2021 were enrolled in this study. Subsequently, 374 RMPP children (PB: 137, without PB: 237) from January 2016 to December 2019 were assigned to the development dataset to construct the nomogram to predict PB and 173 RMPP children from January 2020 to June 2021 were assigned to the validation dataset. The clinical, laboratory and radiological findings were screened using Least Absolute Shrinkage and Selection Operator (LASSO) regression and logistic regression was applied to construct a nomogram. The performance of the nomogram was evaluated by discrimination, calibration and clinical utility. Comparsion of ROC analysis and decision curve analysis (DCA) between nomogram and other models was performed to evaluate the discrimination ability and clinical utility., Results: The development dataset included 374 patients with a mean age of 6.6 years and 185(49.5%) were men. The validation dataset included 173 patients and the mean age of the dataset was 6.7 years and 86 (49.7%) were men. From 26 potential predictors, LASSO regression identified 6 variables as significant predictive factors to construct the nomogram for predicting PB, including peak body temperature, neutrophil ratio (N%), platelet counts (PLT), interleukin-6 (IL-6), actic dehydrogenase (LDH) and pulmonary atelectasis. The nomogram showed good discrimination, calibration and clinical value. The mean AUC of the nomogram was 0.813 (95% CI 0.769-0.856) in the development dataset and 0.895 (95% CI 0.847-0.943) in the validation dataset. Through calibration plot and Hosmer-Lemeshow test, the predicted probability had a good consistency with actual probability both in the development dataset (P = 0.217) and validation dataset (P = 0.183), and DCA showed good clinical utility. ROC analysis indicated that the nomogram showed better discrimination ability compared with model of peak body temperature + pulmonary atelactsis and another model of N% + PLT + IL-6 + LDH, both in development dataset (AUC 0.813 vs 0.757 vs 0.754) and validation dataset (AUC 0.895 vs 0.789 vs 0.842)., Conclusions: In this study, a nomogram for predicting PB among RMPP patients was developed and validated. It performs well on discrimination ability, calibration ability and clinical value and may have the potential for the early identification of PB that will help physicians take timely intervention and appropriate management., (© 2022. The Author(s).)

Background: Microplastics (MPs) are a new global environmental threat. Previously, we showed the biodistribution of MPs using [ 64 Cu] polystyrene (PS) and PET in mice. Here, we aimed to identify whether PS exposure has malignant effects on the stomach and induces resistance to therapy. Methods: BALB/c nude mice were fed 1.72 × 10 4 particles/mL of MP. We investigated PS accumulation in the stomach using radioisotope-labeled and fluorescent-conjugated PS. Further, we evaluated whether PS exposure induced cancer stemness and multidrug resistance, and whether it affected tumor development, tumor growth, and survival rate in vivo using a 4-week PS-exposed NCI-N87 mouse model. Using RNA-Seq analysis, we analyzed whether PS exposure induced gene expression changes in gastric tissues of mice. Results: PET imaging results showed that a single dose of [ 64 Cu]-PS remained for 24 h in the mice stomach. The 4-week daily repetitive dose of fluorescent conjugated PS was deposited in the gastric tissues of mice. When PS was exposed, a 2.9-fold increase in migration rate was observed for NCI-N87 cells. Immunocytochemistry results showed decreased E-cadherin and increased N-cadherin expression, and flow cytometry, qPCR, and western blot analysis indicated a 1.9-fold increase in N-cadherin expression after PS exposure . Further, PS-induced multidrug resistance to bortezomib, paclitaxel, gefitinib, lapatinib, and trastuzumab was observed in the NCI-N87 mouse model due to upregulated CD44 expression. RNA-seq results identified increased asialoglycoprotein receptor 2 ( ASGR2 ) expression after PS exposure, and ASGR2 knockdown decreased cell proliferation, migration, invasion, and drug resistance. Conclusion: We demonstrated that ASGR2 enhanced cancer hallmarks on PS exposure and induced resistance to chemo- and monoclonal antibody-therapy. Our preclinical findings may provide an incentive for further epidemiological studies on the role of MP exposure and its association with gastric cancer., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

A 65-year-old man had unresectable intrahepatic cholangiocarcinoma with a malignant biliary stricture. We used an endoscopic plastic stent to drain the bile. Despite receiving standard chemotherapy, the tumor eventually progressed and cancerous peritonitis developed. We had to exchange plastic stents frequently because of stent occlusion. We had a re-biopsy with EUS-FNA and tested for microsatellite instability, which came back as MSI-high. We administered pembrolizumab, which resulted in a significant reduction of tumor size. We were able to administer long-term chemotherapy without serious side effects by repeatedly exchanging plastic stents for stent occlusion. He has maintained partial response for more than 20 months after receiving pembrolizumab.

Recent observations indicate that, rather than being an all-or-none response, phagocytosis is finely tuned by a host of developmental and environmental factors. The expression of key phagocytic determinants is regulated via transcriptional and epigenetic means that confer memory on the process. Membrane traffic, the cytoskeleton, and inside-out signaling control the activation of phagocytic receptors and their ability to access their targets. An exquisite extra layer of complexity is introduced by the coexistence of distinct "eat-me" and "don't-eat-me" signals on targets and of corresponding "eat" and "don't-eat" receptors on the phagocyte surface. Moreover, assorted physical barriers constitute "don't-come-close-to-me" hurdles that obstruct the engagement of ligands by receptors. The expression, mobility, and accessibility of all these determinants can be modulated, conferring extreme plasticity on phagocytosis and providing attractive targets for therapeutic intervention in cancer, atherosclerosis, and dementia.

Using the templates preliminarily made by 3D design and prototyping methods, defects in the lateral area of the lower jaw of sheep were created using the piezosurgical technique. The defects were replaced by plastic implants obtained by the method of layer-by-layer fusion of the FDM printing-fusing deposition modeling and fixation with titanium screws to the jaw body. In the time interval, plastic implants are replaced by titanium implants obtained by selective laser sintering (SLS) using a 3D printer. To study the processes of reparative osteogenesis, microsamples of tissues of the preimplantation zone were analyzed. As a result, signs of osteo- and fibro-osseointegration were identified. The obtained data are regarded as a prerequisite for further clinical trials of the developed protocols for the sequential replacement of jaw defects using 3D printing.

Polyvinylchloride is universally agreed upon to be the material of choice for tubings and for containers for medical application. Many alterations of the chemical/physical surface conditions, mainly due to an altered extrusion process, could influence its biocompatibility by promoting platelet aggregation. Biocompatibility and safety of the medical device must be preserved, also monitoring the migration of additives within polyvinylchloride during the diffusion process. A large variety of methods are used to verify the correct composition and extrusion of polyvinylchloride but, generally, they need long experimental time and are expensive. The aim of the study is to propose a simple, economic and rapid approach based on Fourier transform-infrared spectroscopy and Coomassie Blue staining. The method has been used to detect chemical and morphological defects caused by an altered extrusion process on 20/75 polyvinylchloride tubings in a blind test. This approach positively identified altered samples in 80% of the cases. The suggested approach represents a reliable and versatile method to detect and monitor surface defects by an easy, inexpensive and reproducible method.

BACKGROUND This study aimed to evaluate the efficacy of a porous polyoxymethylene thermoplastic regulator combined with a three-dimensional (3D) printed template to guide pedicle needle insertion in patients undergoing percutaneous pedicle screw fixation (PPSF) for thoracolumbar fracture. MATERIAL AND METHODS Forty patients were randomly divided into group A, treated using a porous polyoxymethylene thermoplastic regulator combined with a 3D printed template, and group B, who underwent conventional PPSF. Data recorded included the number of pedicle screws successfully inserted on the first attempt, the number of attempts, the time to successful needle insertion, the total time of fluoroscopy, and the duration of surgery. The Visual Analogue Scale (VAS) and the Oswestry Disability Index (ODI) scores one day before surgery, and at day 1, day 7, month 1, and month 3 after surgery were recorded. The postoperative vertebral posterior kyphotic angle (KA) and the rate of change of KA were recorded. RESULTS Group A had a significantly increased total number of successful first insertions compared with group BV (P<0.05). Postoperative VAS and ODI scores of patients in both groups were significantly lower than before surgery (P<0.05), with no significant difference between the two groups at postoperative month 1 and month 3 (P>0.05). The postoperative vertebral posterior KA decreased significantly in both groups after surgery, with no significant difference between the two groups (P>0.05). CONCLUSIONS The use of a porous polyoxymethylene thermoplastic regulator combined with a 3D printed template may improve the success of pedicle insertion in patients undergoing PPSF.

We report the long-term outcome of a case of "full plastic jacket" treatment consisting of three bioresorbable scaffolds to manage a subtotally occluded left anterior descending artery with associated severe bare metal in-stent restenosis. Angiography 36months' post procedure revealed an excellent result with negative fractional flow reserve result. Bioresorbable scaffolds may be an attractive option for in-stent restenosis due to the avoidance of an additional metallic layer, and this case is unusual regarding the total scaffold length used and long term angiographic follow-up., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Aim: Study processes of microbial colonization and persistence of microorganisms in polymer materials for medical use., Materials and Methods: Samples (1 x 1 cm plates) of polymer plastics for production of removable dental prosthesis based on polyurethane and acryl were used, that were incubated with clinical isolates of Pseudomonas aeuruginosa, Staphylococcus aureus in Luria-Bertani broth nutrient media for 24, 48 hours and 7, 14 days and for 1, 5 and 3 months at a temperature of 37 degrees C. Dynamics of interaction process of microorganisms with polymer materials were studied using scanning electron microscope Quanta 200 3D (FEI Company, USA). The samples were fixated after incubation with 10% of neutral formaldehyde, dehydration with alcohols or acetone, typical for SEM, was not carried out, that allowed to conserve the native structure of the samples, including exo-cell matrix of biofilms., Results: Electron-microscopical data on stages of interaction of bacteria with the surface of medical plastics were obtained. Biofilms were shown to be formed on abiotic surfaces and biodestructive changes of plastics appeared. A question on the possibility of prolonged persistence of pathogenic for human microorganisms in artificial prosthesis is discussed., Conclusion: The developed experimental model of formation of biofilm on abiotic surfaces could be the basis for carrying out studies directed on the fight with biofilms, by using SEM.

This feasibility study aims to determine if a low-cost 3D printer (BitsFromBytes 3D Touch) with ABS plastic can print custom mould structures and catheter channels defined in a brachytherapy treatment planning system (Nucletron Oncentra) for patient-specific treatment. Printer accuracy was evaluated through physical measurement, and print quality was investigated by adjusting print parameters (print speed, layer thickness, percentage infill). Catheter positioning and reproducibility were measured over repeated insertions. ABS plastic water equivalency was investigated by comparing Ir-192 HDR source dose distributions, measured with radiochromic film, in ABS plastic and in water. Structures and catheter channels were printed accurately to within 0.5 mm laterally and 1 mm in the vertical print direction. Adjusting print parameters could reduce print time, albeit with reduced print quality. 3.5 mm channel diameters allowed for easy catheter insertion. Catheter positioning was reproducible to within 0.5 mm but, because of catheter flex within the channel, was on average 1 mm offset from defined TPS positions. This offset could be accounted for by repeating the treatment planning CT scan with the printed mould positioned on the patient. Dose attenuation in ABS plastic and in water was equivalent to within the measurement limitations. While clinical uses for this particular low-cost printer and ABS plastic are limited by print size restrictions and non-certification for biocompatibility, it has been demonstrated that a low-cost 3D printer set-up can accurately create custom moulds and catheter channels potentially acceptable for clinical use.

Introduction: This ex vivo study evaluated the accuracy of the Root ZX electronic apex locator (EAL) (J Morita Corp, Kyoto, Japan) in determining the working length during retreatment of canals sealed with 2 different carrier-based obturating materials (ProTaper Obturator [Dentsply Maillefer, Ballaigues, Switzerland] and GuttaCore [Dentsply Maillefer]) and also evaluated whether they influenced its accuracy differently., Methods: Fifty extracted single-rooted human teeth with sound apices were selected for the study. We measured canals with the direct visual technique using a #10 K-file and shaped them with ProTaper Universal instruments (Dentsply Maillefer) up to this predetermined length. After instrumentation, we determined the canal length again using the visual technique (direct length [DL]). This value was considered the "reference point." Specimens were then placed in a tooth holder (Pro-Train; Simit Dental, Mantova, Italy), and the canal length was electronically measured (electronic length 1 [EL1]). Specimens were then obturated with ProTaper Obturators (group 1, n = 25) and GuttaCore (group 2, n = 25). Seven days later, a new electronic length was determined (electronic length 2 [EL2]) during retreatment procedures in the presence of the obturating material. EL1 and EL2 values were compared with DL using the Bland and Altman method. The different influences of the tested materials on the accuracy of the EAL were calculated with repeated measures analysis of variance., Results: Both EL1 and EL2 values provided a statistically significant overestimation of the actual canal length (DL [P < .05]), with the EL2 values higher from DL. The 2 different materials did not influence the accuracy of the EAL differently (P = .486)., Conclusions: The measurements obtained with the EAL tested during orthograde retreatments can lead clinicians to overinstrumentation and consequent overfilling of the endodontic space., (Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Endoscopic retrograde cholangiopancreatography (ERCP) is used for the management of benign iatrogenic biliary strictures after cholecystectomy and liver transplantation. Multiple stents can injure biliary circulation. If resolution of reversible ductal edema and/or ischemia is the mechanism for successful therapy then single stent placement for benign biliary stricture should work. Retrospectively reviewed ERCP records between November 1999 and 2012 provided 25 patients with repeat ERCPs performed at 10-week intervals or if symptoms of stent occlusion were present. If strictures did not improve between stent changes and if removal was not an option, hepaticojejunostomy was used. Strictures resolved in 72% of patients. Seven patients underwent hepaticojejunostomy. Three had ERCP-related complications. No stricture recurrence occurred during the follow-up period. Endoscopic single plastic stent treatment of benign biliary iatrogenic strictures has comparable success to multiple stenting. Many postsurgical strictures may have reversible ischemic/edematous component with stenting to maintain bile drainage.

Nanomembranes have been prepared by spin-coating mixtures of a polythiophene (P3TMA) derivative and thermoplastic polyurethane (TPU) using 20:80, 40:60, and 60:40 TPU:P3TMA weight ratios. After structural, topographical, electrochemical, and thermal characterization, properties typically related with biomedical applications have been investigated: swelling, resistance to both hydrolytic and enzymatic degradation, biocompatibility, and adsorption of type I collagen, which is an extra cellular matrix protein that binds fibronectin favoring cell adhesion processes. The swelling ability and the hydrolytic and enzymatic degradability of TPU:P3TMA membranes increases with the concentration of P3TMA. Moreover, the degradation of the blends is considerably promoted by the presence of enzymes in the hydrolytic medium, TPU:P3TMA blends behaving as biodegradable materials. On the other hand, TPU:P3TMA nanomembranes behave as bioactive platforms stimulating cell adhesion and, especially, cell viability. Type I collagen adsorption largely depends on the substrate employed to support the nanomembrane, whereas it is practically independent of the chemical nature of the polymeric material used to fabricate the nanomembrane. However, detailed microscopy study of the morphology and topography of adsorbed collagen evidence the formation of different organizations, which range from fibrils to pseudoregular honeycomb networks depending on the composition of the nanomembrane that is in contact with the protein. Scaffolds made of electroactive TPU:P3TMA nanomembranes are potential candidates for tissue engineering biomedical applications.

Study Design: Retrospective study at a rehabilitation center., Objectives: Patients with spinal cord injury, even if they are wheelchair users, sometimes suffer from fractures of the lower limb bones. As their bones are too weak to have surgery, and because a precise reduction is not required for restoration, such patients are often indicated for conservative treatment. This case series study investigated the use of a hinged, soft-plastic brace as a conservative approach to treating fractures of the lower extremities of patients with spinal cord injury., Setting: National Rehabilitation Center, Japan., Methods: Fifteen patients (male, n=10; female, n=5; average age, 52.7 years) with 19 fractures of the femur or the tibia who were treated with a newly-developed hinged, soft-plastic brace were studied. All of them used wheelchairs. We analyzed the time taken for fracture union and for wearing orthotics, degree of malalignment, femorotibial angle and side effects., Results: The fractures in this series were caused by relatively low-energy impact. The average time taken for fracture union was 80.1 (37-189) days, and the average amount of time spent wearing orthotics was 77.9 (42-197) days. On final X-ray imaging, the average femorotibial angle was 176.9° (s.d. ±8.90), and 15° of misalignment in the sagittal plane occurred in one patient., Conclusion: A hinged, soft-plastic brace is a useful option as a conservative approach for treating fractures of the lower extremities in patients with spinal cord injury.

Our experience of elaboration and introduction of various synthetic materials proves trustworthily the necessity of conduction of a long-term complex investigations by various scientific centers with the objective of creation and application in Ukrainian surgical practice a medical materials of own production as accessible, safe and qualitative preparations. And more, the Ukraine may implement such programs, taking into account a great scientific-technical power she owes.

Study Design: Biomechanical human cadaveric cervical flexibility testing with direct load-sharing measurement., Objective: To determine if the flexibility and load-sharing characteristics of a functional spinal unit were affected by anterior treatments for cervical pathologies., Summary of Background Data: With advancements in polymers, anterior cervical plates have used thermoplastics including recent designs from biodegradable polylactide acids. However, the difference in material properties between metal and polymer can be significant., Methods: Thirteen cervical spine specimens were subjected to 5 treatments at C4-C5. Each treatment for each specimen was subjected to multidirectional flexibility testing. The third cycle was used for treatment comparisons., Results: With the integrated load cell spacer, the mean range of motion for the functional spinal unit measured on average 104% + or - 40% normalized to the intact control. The mean biodegradable and titanium plate were 55% + or - 31% and 40% + or - 36%, respectively. Both plates exhibited statistically lower mean range of motions (P = 0.001 and P < 0.001) compared with spacers. The load transmitted through the interbody space was 54% + or - 20%, 43% + or - 20%, and 33% + or - 15% on average for the spacer, biodegradable, and titanium plate constructs, respectively. No statistically significant difference was detected between the biodegradable plate and spacer (P = 0.214)., Conclusions: From this research, a biodegradable plate offers immediate postoperative stability significantly different than spacer alone treatments but with graft load sharing that is statistically no different. Thus, the intrinsic lower native material modulus of elasticity of biodegradable polymers has biomechanical implications. However, clinical evidence, particularly for long-term outcomes, will be required in understanding the efficacy of biodegradable polymers.

A provisional restoration in combination with an implant-retained restoration provides many of the same benefits as nonimplant-retained fixed restorations. Provisional restorations serve as a diagnostic tool to confirm esthetics, contours, accessibility for oral hygiene, and can be used to duplicate the definitive restoration. A provisional restoration allows for communication between the patient, dentist, and technician. The soft tissue around the implants can heal according to the contours of the provisional restoration. However, implant-retained treatment can require an extended period of osseointegration, and provisional treatment can be a challenge if a removable prosthesis is provided because adjustments of the denture may become necessary during healing. This article presents a case report that describes the simultaneous placement of implants with the connection of fixed provisional restorations to prefabricated plastic provisional abutments.

Unlabelled: The paper presents clinical evaluation of the polypropylene-polyester knit used as a cranioplasty material., Material: Between year 1980 and 2002 275 cranioplastic procedures using the polypropylene-polyester plates Codubix were carried out in the Department of Neurosurgery of the Medical University of Łódź. There were 146 patients who primarily sustained head injuries and 129 non-traumatic patients with craniectomies carried out for various other reasons. In the majority of cases, i.e. in 158 patients, cranioplasty was performed later than 6 months after the primary surgery. The largest implant measured 430 cm2., Results: Excellent and good outcome was achieved in 92% of the patients whereas the rate of local infection was 8%., Conclusions: Codubix knitted polypropylene-polyester implant proved to be useful and a safe cranioplastic material.

The use of biliary and pancreatic stents has increased significantly during the last 2 decades because of improvements in available endoscopes and endoscopic accessories, as well as better techniques. The number of endoscopists who can successfully complete these demanding procedures has also increased, as have the indications for stent therapy in biliary and pancreatic diseases. Stents are now made in various shapes and configurations from different types of polymers (plastics), various expandable metallic alloys, and bioabsorbable materials. Most of the available data relate to plastic and metallic stents for biliary tract disease; the data for pancreatic disease are fewer and involve a smaller number of patients. This article reviews the most recent available data concerning biliary and pancreatic stents and discusses possible future developments. It does not attempt to cover all data reported in biliopancreatic stent therapy.

Background: High stent cost is considered the major drawback of self-expanding metal stents for dysphagia palliation in patients with inoperable esophageal strictures. We report our experience with a self-expanding plastic (Polyflex) stent, the cost of which is half that of the metal stents., Methods: Between September 1999 and April 2001, 16 dysphagic patients (15 men; mean age, 69.4 +/- 14.5 years; range, 49-100 years; mean dysphagia score, 3.31 +/- 0.6) with esophageal strictures who underwent Polyflex stent placement (insertion device diameter, 12-14 mm; postexpansion inner stent diameter, 16-21 mm; stent length, 9, 12, and 15 cm) were studied prospectively. The strictures were caused by postsurgical recurrence of gastric/esophageal cancer at the anastomotic site in five patients, primary esophageal cancer in four patients, esophagocardia junction cancer in four patients, metastatic mediastinal lymph nodes from a primary lung cancer invading the esophagus in 1 patient, and benign peptic stricture in two elderly patients. All the patients were prospectively followed until death., Results: Stent insertion was technically successful in 12 patients (75%). Stent placement failed in four patients (25%) because of failure to pass the delivery catheter across the stricture in three patients and failure of the stent to open in one patient. Early and late stent migration occurred in two patients and 1 patient, respectively. Tumor overgrowth occurred in 1 patient. The mean dysphagia score 7 days after stent placement was 1.1 +/- 0.9. Mean survival was 100.6 +/- 71.2 days (range, 8-225 days)., Conclusion: Self-expanding Polyflex stents are safe and effective for inoperable esophageal strictures and have an acceptable technical success rate. Further experience, better selection criteria, and design improvements should improve results.

Whether as substitutes for glass and metal, or completely novel injection moulded applications, engineering polymers offer a range of opportunities for developing cost-effective, safe and smart medical devices.

Background: The systematic use of metal stents to treat biliary obstruction is restricted by high cost compared with plastic stents. The aims of this study were to compare cost and efficacy of plastic stents and metal stents in the treatment of patients with malignant common bile duct strictures and to define factors that predict survival of these patients., Methods: One hundred eighteen patients (mean age 75 years) with malignant strictures of the common bile duct were randomized to placement of a plastic stent or metal stent. Comparisons were made with the Mann-Whitney or chi-square test as indicated; survival rates were compared with a Cox proportional hazards model., Results: There was no significant difference in survival between the two groups. Time to first obstruction was longer for patients in the metal stent group (metal stent, median not reached vs. plastic stent, 5 months; p = 0.007). The number of additional days of hospitalization, days of antibiotic therapy, and the numbers of ERCPs and transabdominal US procedures was significantly higher in the plastic stent group. After multivariate analysis, only the presence of liver metastases was independently related to survival (p < 0.0005; OR = 2.25). This variable defined a group with a shorter survival. Median survival of patients with hepatic metastasis at diagnosis was 2.7 months compared with 5.3 months for patients without liver metastasis; in the latter group, the overall cost associated with metal stents was lower than for plastic stents., Conclusions: Metal stent placement is the most effective treatment of inoperable malignant common bile duct stricture. Placement of a metal stent is cost effective in patients without hepatic metastases, whereas a plastic stent should be placed in patients with spread of the tumor to the liver.

This review of applications close to the market as well as those on the horizon highlights the benefits of micromoulding technology for cost-effective large-volume production of microstructured plastic components.

Background: Container integrity is critical for maintaining sterility of cryopreserved cellular therapy products. We investigated a series of catastrophic bag failures, first noticed in early 2001., Methods: Process records were reviewed for all PBPC and lymphocyte products cryopreserved in bags from January 2000 through April 2002. Patient charts were also reviewed., Results: One thousand two hundred and four bags were removed from storage for infusion to 261 patients. All products had been cryopreserved in Cryocyte poly(ethylene co-vinyl acetate) (EVA) bags in either 10% DMSO or 5% DMSO and 6% pentastarch. Product volumes were 25-75 mL, and bags were stored with overwrap bags in a liquid nitrogen tank. From January 2000 to April 2001, failure occurred in 10 of 599 (1.7%) bags. From May 2001 to April 2002, 58 of 605 (9.6%) bags failed, typically with extensive fractures that were visible before thaw. Of the 58 that failed, 24 were salvaged by aseptic methods and infused to patients under antibiotic coverage; 10 of those 24 (42%) had positive bacterial cultures. Bag failures were not related to product type, cryoprotectant solution, liquid versus vapor storage, or freezer location. Failures were linked to use of four Cryocyte bag lots manufactured in 2000 and 2001. After replacing these lots with a 1999 Cryocyte lot and with KryoSafe polyfluoroethylene polyfluoropropylene (FEP) bags, no more failures occurred in 75 and 102 bags, respectively, thawed through April 2002., Discussion: High rates of bag failure were associated with four Cryocyte bag lots. No serious adverse patient effects occurred, but bag failures led to microbial contamination, increased product preparation time, increased antibiotic use, and increased resource expenditure to replace products.

Forty extracted maxillary central incisors were instrumented at the working length to a #50 file. The roots were sectioned transversely with a diamond disk at 7 mm from the anatomical apex. At the opening of the root canal of each section, hemicircular cavities were drilled with a specially designed bur. The corresponding root sections were cemented with glue, thus obtaining root canals with similar cavities that simulated internal resorptions. Teeth were embedded in plaster casts to facilitate their handling. The specimens were randomly separated into four groups of 10. The following obturation techniques were evaluated: lateral compaction (group A), hybrid technique (group B), Obtura II (group C), and Thermafil (group D). AH26 was used as the sealer. After obturation, the plaster was removed and the teeth were radiographed in buccolingual and mesiodistal directions to evaluate the quality of the obturation at the IRC. The incisors were then cut with a scalpel at the same level as the previous section, to examine, under a stereomicroscope, the type of material that filled the IRC. Obtura II gave the best results and in most of the specimens obturated with this technique, the IRC were filled mainly with gutta-percha. Statistical analysis of the data indicated that the differences between group C and the other groups were significant (P < 0.05).

The aim of this study was to investigate the leakage along the apical portion of warm gutta-percha obturated curved canals. Human mandibular premolars with single, curved (21 degrees-40 degrees) canals were prepared using the Lightspeed technique. Two groups of prepared canals, matched according to curvature and prevalence of apical transportation, were obturated by two techniques. Coronal gutta-percha was removed immediately after root obturation was completed to simulate the procedure for post space preparation. Leakage along the apical 3 mm of root filling was measured with a fluid transport device. Vertical condensation of warm gutta-percha and Pulp Canal Sealer provided less leakage than Thermafil plastic obturators and AH26 sealer (P = 0.002).

Background: Alternatives to fascial closure of the abdominal wall are increasingly used in critically ill patients. They pose practical and logistical problems in management which are described in this single-institution study., Methods: Between January 1994 and December 1997, 157 predominantly young male patients (100 trauma and 57 non-trauma) underwent temporary abdominal content containment (t-ACC) using plastic bags or polyglactin mesh. Indications for t-ACC were severe sepsis requiring reoperation, abdominal compartment syndrome, abdominal wall tissue loss or a combination of these. A total of 385 laparotomies were performed., Results: Two t-ACC procedures failed owing to technical error and two were complicated by enteric fistulas. Six patients underwent early definitive abdominal closure within 15 days. The remaining survivors had a protracted hospital stay (mean(s.d.) 44.6(26.6) days) and all developed incisional hernias which were challenging to repair. The overall mortality rate was 44 per cent., Conclusion: Plastic bags were cheaper and as effective as polyglactin mesh for t-ACC. Survivors require a multidisciplinary approach in management, undergo a protracted hospital stay and later need complex incisional hernia repairs.

Strong supplier-customer relationships are essential to the development of polymer materials that are suitable for manufacture. This is especially true in the medical device field. Issues such as understanding the customer's material specification, simple medical compatibility assessments, communicating polymer developments and changes and a co-development business strategy are addressed in this article. The subject is dealt with from the viewpoint of a medium-to-large-volume injection moulder of plastic components for the medical device industry.

Plastics are not only the proverbial everyday commodity, but they also permeate almost every aspect of medical devices, from technology to clinical application. This article addresses some of the confusing features of plasticity as they relate to the materials called plastics, to the phenomena of material plasticity, and to the clinical and biological usage of the word.

Surgical changes in the contour of soft tissue and bone of the craniomaxillofacial structures may require use of a biologic graft or alloplastic implant. Autologous materials are preferred; however, the harvesting procedure, donor site, and its associated morbidity are the disadvantages of using autografts. There are numerous types of alloplastic implants and they all differ in how they interact with host tissues. Factors such as implant texture, ability to integrate with host tissues, and rate of resorption all influence the overall success of different implants. In this article, we discuss some considerations in the use of biologic grafts and alloplastic implants in facial plastic and reconstructive surgery.

The clinical use of Hexcelite in plastic surgery and burns to construct strong, light-weight splints and to provide protective cover for skin grafts is described. Several examples are presented to illustrate its simplicity and adaptability.

Plastic is used in addition to metallic osteosynthesis in fracture treatment. The object of the present study was to test the usefulness of plastic as the sole fixation material in experimental osteotomies of cancellous bone and in tibial cortical bone grafts. A total of 32 rats were used. In the first group, consisting of 12 rats, the lateral condyle of the right femur was detached and refixed with Silar. In the second group, a tibial cortical bone graft was detached and refixed with Silar in 12 rats and left unfixed in eight. In the first group fixation of the condyle was successful in all cases but one, but in the second group sufficiently stable fixation of the cortical bone graft was not attained and fractures occurred in half the cases.

In vivo gas transfer performance, during veno-venous bypass, is presented for one form of the Oxford membrane lung in which vortex mixing is induced in blood flow across a dimpled polypropylene membrane. Good agreement has been found with in vitro data presented in an earlier paper. Two experiments were extended to attain total extracorporeal CO2 removal with apnoeic diffusion oxygenation to motionless lungs. Measurements of arterial oxygen partial pressure during apnoea suggest that the time-constant for equilibration of alveolar nitrogen partial pressure with that on the gas side of the membrane lung is of the order of 100 min.

A tube made of polypropylene has been used both as a stent after canalicular reconstruction or repair and as a bypass device to drain tears when the canaliculi have been destroyed. The tube comes in different sizes, can be cut to any length, can be bent to any shape and can easily be flanged at the nasal end by the surgeon. The tube has good capillarity and drains well. There is enough tissue reaction around it so that it will not extrude, yet when it is used as a stent it can easily be removed.

Three 5 to 14-year old patients with generalized developmental disturbances of dental hard substance--clinical diagnosis: dentinogenesis imperfecta--are used as examples of age-specific therapy groups in order to demonstrate the various courses of therapy. Early therapy of permanent teeth consists of treating enamel defects with UV hardening resin of the Nuva system. To evaluate adhesion of dental hard substances to resin, it is proposed to use adhesive matrices.