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The aim of this study was to assess the effect of time and the ultrasonic activation of ethylenediaminetetraacetic acid (EDTA) in removing the smear layer of at root canal. A total of 60 bovine inferior incisors were transversely sectioned and instrumented; A smear layer was added in the root dentin surface. The specimen were then divided into six groups according to the following final irrigation protocols: Group (G) 1: conventional irrigation with sodium hypochlorite (NaOCl); G2: conventional irrigation with NaOCl + EDTA for 20 s; G3: conventional irrigation with NaOCl + EDTA for 60 s; G4: passive ultrasonic irrigation (PUI) with NaOCl; G5: PUI with NaOCl + PUI with EDTA for 20 s; G6: PUI + NaOCl and PUI with EDTA for 60 s. Samples were analyzed by scanning electron microscope (SEM) at ×500 increase. The images were measured by three blinded evaluators and classified in scores ranging from 1 to 5. The results were analyzed by the Pearson correlation test and the ANOVA nonparametric Kruskal-Wallis and Dunn's tests were used for the comparisons. Irrigated samples only with NaOCl (G1 and G4) had higher scores when compared with other groups. G5 and G6, irrigated with 17% EDTA and ultrasonic irrigation had lower scores. However, there was no statistically significant difference in G2 and G3, where there was no irrigation. It was concluded that irrigation with 17% EDTA for 20 s promoted the effective removal of smear layer, regardless of ultrasonic irrigation., (© 2016 Wiley Periodicals, Inc.)

The present work aims at comparing the life cycle and estimating, based on life tables, the patterns of fertility of populations of A. aegypti (L.). The life cycles were studied at the temperature of 26 +/- 2 degrees C, and 12h photophase. The development period, egg viability and larval and pupal survival were evaluated daily as well as adult longevity and fecundity. Tables of fertility life were built. The durations of egg, larva and pupa stages varied from 3,9 to 4,5 days, from 6,4 to 8,3 days and from 2,0 to 2,5 days, respectively. The life table parameters for A. aegypti from Brejo dos Santos, Boqueirão, Itaporanga and Remígio, being, respectively, Ro = 104,03, 84,58, 113,37 and 91,18; rm = 0,92, 0,78, 0,89 and 0,88; and lambda = 2,50, 2,18, 2,43 and 2,41. The populations of Brejo dos Santos and Itaporanga had the biggest potential of growth in relation to the other populations. The results showed a differentiated pattern of growth and a biotical potential in the populations of A. aegypti originated from different municipal districts of the state of Paraíba.

Rumors of Aedes aegypti (L.) resistance to temephos in diferent Brazilian states justified this research, whose objective was to verify and characterize the resistance to temephos in A. aegypti populations from Paraíba State. The temephos resistance was evaluated and characterized through a diagnostic dose of 0.012 mg/l and concentration-mortality curves. The mortality data of multiple concentrations were submitted to Probit analysis, and the resistance ratios (RR) were figured out from the CL50s of the survived population and CL50 a laboratory susceptible population. All the A. aegypti populations showed resistance to temephos. The Sítio Piabas population with RR = 4.0, showed lower resistance, the Campina Grande with RR = 6.0, Lagoa do Mato with RR = 9.3 and Capim de Cheiro with RR = 9.0, showed a moderate resistance, and Boqueirão with RR = 11.0, Brejo dos Santos with RR = 16.6 and Itaporanga with RR= 15.6, showed intermediate levels of resistance to temephos. These results confirm the need of a continuous monitoring and managing program of A. aegypti resistance in Paraíba State.

The present work aimed at estimating the thermal requirements for the development and the number of generations per year of Aedes aegypti (L.) under natural conditions. The life cycle of A. aegypti populations was studied at constant temperatures of 18, 22, 26, 30 and 34 degrees C, and 12 h photophase. The development period, egg viability and larval and pupal survival were evaluated daily as well as adult longevity and fecundity. The low threshold temperature of development (Tb) and the thermal constant (K) were determined. The number of generations per year in laboratory and field were also estimated. The favorable temperature to A. aegypti development is between 21 degrees C and 29 degrees C, and to longevity and fecundity is between 22 degrees C and 30 degrees C. The egg to adult basal temperature, thermal constant and the number of generations in field were, in order, 9.5, 8.5, 3.4, 7.1, 13.5 degrees C; 244.5, 273.9, 298.5, 280.9 and 161.8 degree-days; and 21.9, 23.8, 24.2, 21.1 and 22.1 generations in populations from Boqueirão, Brejo dos Santos, Campina Grande, Itaporanga and Remígio.

The viability of inertization of galvanic wastes through their incorporation in clay-based materials, such as common formulations for tiles and bricks, is here studied by determining the leaching kinetics in different media. Metals immobilization is assured by firing at reasonably high temperatures, since intimately contact and/or reaction between residue and clay particles is promoted but also due to formation of insoluble metal oxides that rest unreactive towards clay grains. For most metals, leaching rate follows a zero-order kinetic law, with values between 0.001 to 0.1 mg/(g day cm2). Leaching velocity tends to increase with rising atomic numbers: Zn < Cu < Ni < Cr. These values depend exponentially on the relative sludge content.

In EU countries approximately 150,000 tons/year of galvanic sludges are generated by 4000 industrial units from the corresponding wastewater treatment plants. These sludges are generally classified as hazardous (European Waste Catalogue as adopted in Council Decision 2000/532/CE and as amended by Decisions 2001/118/EC, 2001/119/EC and 2001/573/CE), basically due to the presence of heavy metals. This work attempts to better understand the physical and chemical characteristics of these sludges, by studying 39 samples collected in different Portuguese industries that should represent all kinds of similar wastes independent of their place of generation. Chemical composition and leaching characteristics are given, together with density, grain size distribution, and specific surface area values. Statistical analysis was used for grouping the wastes according to chemical parameters, which might be useful to predict potential reuse as raw materials for different applications.

Background: The concentration of platelets into an activated growth factor (AGF) gel may stimulate graft consolidation into a fusion mass. Preoperative hemodilution and intraoperative clot activation may also reduce the overall blood loss. Consequently, the need for postoperative transfusions may also be reduced., Objective: The objective of this work was to report our experience with AGF platelet gels in transforaminal lumbar interbody fusion (TLIF) procedures., Methods: A consecutive series of patients between 1996 and 1999 undergoing one- and two-level TLIFs with AGF were compared with a consecutive series of TLIF patients who did not receive AGF. Sixty-two control subjects who did not receive AGF and 22 patients who received an AGF platelet gel were compared after 41 and 34 months of follow-up, respectively., Results: On average, the AGF group required 18 minutes of additional preincision anesthesia (P = 0.0001). No statistical differences in the operative times, estimated blood loss, postoperative drainage, percentage of patients requiring a transfusion, or length of hospitalization were appreciated between the two groups. The 19% decrease in the arthrodesis rate of the AGF group, as compared with the control group, did not reach statistical significance. Platelet counts from the AGF platelet concentrates demonstrated an average 3.5-fold increase compared with preoperative serum levels., Conclusions: The theoretical benefits of AGF platelet gel technology were not clinically appreciated. The cost of implementing this technology may therefore outweigh its theoretical benefits.

The incorporation of several industrial wastes in ceramic matrixes had been attempted as an effective low expense technique for the fixation of metallic species in usable products or simply to reduce the residue volume for further disposal. However, the dominant mechanism of the inertization process and the relevant influent parameters are still unknown, mostly due to the complexity of the systems. This work reports the effect of several processing parameters such as the mixing time, the calcination temperature and duration, the relative amount of sludge, and the physical aspect of the sample (powdered or pressed pellets) on the fixing level of relevant species (SiO2), SO4(2)-, Zn, Ni, Ca, Cu, Cr) by leaching in different media (aqueous, acetate, and citrate). Statistical tools were used to define the relevance of each experimental variable on the inertization process of the used galvanic sludge. The relative amount of sludge in the mixture, the calcination temperature and the agglomeration state of the sample were found to be the most influent parameters of the inertization process. The incipient reaction between sludge and ceramic matrix components points out for the dominance of a macro-encapsulation mechanism., (Copyright 2003 Elsevier B.V.)

Hydroxide-metal sludges from electroplating industry are a potential source of environmental contamination due to their high content of heavy metals. The incorporation of these residues in a ceramic matrix can be a promising way to suppress the harmful effect of metals normally present in those sludges. This work reports the role of the mixing time between the waste and ceramic materials and of the calcination step on the fixing level of several metal-containing species (Al, Zn, Ni, Fe, Ca, Cu, Cr) after sequential leaching in different media (aqueous, acetate and citrate). A strong and/or long mixing process will promote the deagglomeration of the coarser agglomerates and then will increase the reactivity of remaining grains towards the ceramic material during the calcination. As a consequence, inertization is improved for fired samples. With non-calcined samples leaching increases as a result of increasing dispersability/availability of species., (Copyright 2003 Elsevier B.V.)

This retrospective study was designed to document the incidence and types of perioperative complications that occurred with anterior spinal fusion surgery performed solely by an orthopedic spine surgeon. This study is contrasted to previous studies that document complications from anterior approaches performed by an orthopedic surgeon with the assistance of a general or a vascular surgeon. Specifically, the procedures included thoracotomies, thoracolumbar retroperitoneal, and lumbosacral approaches. Our sample consisted of 450 patients who underwent anterior spinal fusion between levels T1 and S1, from 1985 to 1997. Patient and surgery characteristics included age, sex, diagnosis, levels of fusion, blood loss, operative time, hospitalization time, complications, American Society of Anesthesiologists state, assessment of risk factors, previous surgery, and surgical approach used. Average follow-up was 41.69 months, with a minimum of 12 months and a maximum of 132 months. Our results indicated that anterior procedures performed solely by our senior orthopedic surgeon had a lower incidence of complications, less blood loss, and shorter operative time than anterior procedures performed by an orthopedic surgeon and a vascular or a general surgeon. Our findings suggest that the anterior spinal exposure is a safe approach that may be performed solely by a spinal surgeon who is knowledgeable and experienced.

The risk of sustaining a stinger, CCN, or a more serious catastrophic injury to the cervical spine increases with increasing stenosis. The RR of a player sustaining a second stinger or CCN increases exponentially when compared with the risk of a player sustaining an initial stinger or CCN. Intravenous steroids have no role in the management of stingers or CCN. Players who remain symptomatic after a stinger, players with persistently abnormal diagnostic studies after a stinger, and any player who experiences a CCN should be excluded from further participation in contact sports.

Background Context: Evidence demonstrating the biomechanical effects of the Hueter-Volkmann principle on vertebral body growth in spinal deformities is lacking. Bracing a scoliotic curve should, in theory, unload the growth plates on the concave side of the vertebral bodies near the curve's apex. Growth stimulation, leading to structural remodeling of the vertebral bodies, on the curve's concave side may explain the improvement or lack of curve progression, as measured by Cobb angles, reported with successful brace management of adolescent idiopathic scoliosis (AIS)., Purpose: To determine whether brace treatment stimulated asymmetric chondrogenesis in the apical three vertebral bodies., Study Design: A prospective cohort of patients with AIS receiving brace treatment were followed from the initiation of brace treatment until skeletal maturity. Patients were then retrospectively divided into those with and without radiographic progression. This post hoc analysis was included to determine risk factors for curve progression., Patient Sample: Forty-one skeletally immature patients with AIS meeting criteria for brace treatment were followed until skeletal maturity. All patients were treated with thoracolumbosacral orthotics (TLSOs)., Outcome Measures: The positional derotation of the TLSO on the spine was measured by comparing the initial radiograph with the first radiograph in a brace. The long-term structural changes of the vertebral bodies were determined by comparing the initial and final radiographs. Differences in initial radiographic parameters between the groups of patients with AIS with and without curve progression indicated predictive factors for successful brace treatment., Methods: Initial radiographic measurements were compared with those observed in a brace and those observed at final follow-up. The same analysis was retrospectively repeated comparing patients with AIS with and without radiographic progression., Results: Cobb measurements (p=.0001) and concave-to-convex height ratios of the apical three vertebral bodies improved when the brace was initially applied (p=.0035). Structural remodeling or a rotational correction of the apical three vertebral bodies was appreciated only in patients with flexible curves (p=.01)., Conclusion: Brace application results in immediate positional derotations of the spine in patients with AIS. These positional derotations were maintained only in patients with flexible curves, at final follow-up. Brace treatment was not recommended in patients whose curves did not correct at least 20% in a TLSO.

Fusion levels are selected with the goal of having a balanced physiologic spine on the postoperative films. We have proposed an algorithm for selecting fusion levels based on the King-Moe scoliosis classification scheme and the flexibility of a compensatory curve. We propose the acronym TEAMS as a pneumonic. Curve type defines the region of the spine to be fused. The ends of the Cobb measurement around the region are the temporary endpoints. The endpoints are extended to avoid an apex due to the sagittal or frontal planes. The mobile disc is defined at the caudal end of the fusion area. Finally, the bending films, traction films, or intraoperative films are used to define the stable zone of Harrington that must contain the ends of the fusion mass. This scheme yields a simple, easily taught algorithm that results in reproducible endpoints for scoliosis fusion.

Retrieved polyethylene liners and femoral heads from a consecutive series of revision components of one design were examined. All patients had Long-Term Stable Fixation (OsteoTechnology International, Timonium, Md) total hip arthroplasties (THAs) implanted between 1987 and 1992. The retrieved femoral heads and liners from patients with osteolysis were compared to those without osteolysis. Patients with osteolysis had significantly thinner polyethylene (5.1 mm versus 7.4 mm, P<.01 ) and a higher linear wear rate (0.5 mm/y versus 0.3 mm/y, P=.05). The average femoral head surface roughness also was significantly greater in patients with osteolysis (67 nm versus 35 nm, P<.05). Patients with osteolysis had more total volumetric wear, total linear wear, and volumetric wear rate compared to patients without osteolysis. Age, obesity index, time in situ, and cup inclination were not different between the two groups. Excessive polyethylene wear, probably accelerated by surface roughness of the femoral heads, was associated with pelvic osteolysis in these patients.

No previous study has compared the complications between anterior/posterior and transforaminal interbody fusions. We performed a retrospective analysis of 164 patients to compare the complications and associated predictive factors of the two techniques of circumferential lumbar fusion. Fifty-three had same-day anterior/posterior fusion (group 1), and 111 had transforaminal interbody fusion (group 2). Mean operating time (p < 0.0001) and hospital stay (p < 0.0001) was significantly longer for group 1 patients. Average blood loss was greater for group 1 patients (p < 0.01). Higher complication rates were found in group 1 patients (p < 0.004). Wound infection occurred more frequently in patients with adjunctive treatment (p < 0.04). Hospital stay was an independent predictor of complications in both groups. In group 1, body mass index was independently associated with complications. In group 2, both hospital stay and adjunctive treatment were predictive of complications. Transforaminal lumbar interbody fusion is the preferred technique because it is associated with shorter operating time, less blood loss, shorter hospital stay, and lower incidence of complications.

Multilevel anterior cervical discectomy and fusion (ACDF) remains a difficult problem. A recently described surgical technique for multilevel ACDF has eliminated the morbid complications associated with harvesting iliac crest bone graft (ICBG) while maintaining the advantages of using autologous bone graft. A matched-pairs t test was used to compare the estimated costs of 27 ACDFs using titanium surgical mesh, local autologous bone graft, and anterior plate instrumentation with 27 ACDFs using ICBG and plate fixation. The three variables considered were cage cost, operating time (cost), and hospitalization cost. The estimated costs for the two surgical procedures were not significantly different. Thus, the time saved by not harvesting an ICBG was comparable to the cost of the cage. Harvesting ICBG also increased the morbidity rate by 22%.

A case of distal aortic occlusion after circumferential lumbar spine surgery is presented. The paradoxical clinical findings are discussed.

The purpose of this review was to determine whether the literature supports in situ prophylactic pinning of the hip contralateral to a hip with a slipped capital femoral epiphysis (SCFE). Three hundred twenty-five articles on SCFE between 1931 and 1998 were reviewed. Two hundred six studies were used to establish normative data. Patients with a unilateral SCFE were 2,335 times more likely to develop a SCFE in the contralateral hip when compared to children in the general population experiencing an initial SCFE. Because a majority of these sequential SCFEs were detected and treated early, we concluded that close follow-up and not prophylactic pinning was most supported by the literature.

Although isolated subaxial cervical spine stenosis in achondroplasia is less common than narrowing at the foramen magnum, thoracolumbar junction, or lumbar spine, it should be recognized as a distinct entity. These congenital changes usually become symptomatic when combined with degenerative changes in early adult life. Yearly monitoring of adult achondroplastic patients for signs and symptoms of cervical myelopathy or radiculopathy is recommended. When this develops, early surgical decompression should be considered, as these patients generally do not respond well to nonoperative treatment. The altered anatomy and small size make these cases particularly challenging. A thorough history and examination and complete diagnostic testing are necessary to gain an understanding of the exact etiology of the symptoms. Wide laminectomies and foraminotomies are then usually required to decompress the spinal cord and nerve roots. Fusion using internal fixation may be required to stabilize the spine if excessive bone is removed. (Curr Surg 57:354-356)

Study Design: A review of the charts and radiographs of 22 patients with idiopathic lumbar, thoracolumbar, and thoracic scoliosis who underwent single-stage anterior fusion with rigid third-generation instrumentation and titanium surgical mesh implants., Objectives: To validate a new technique for scoliosis correction by assessing the initial correction of deformity, trunk shift, and rotation. Perioperative statistics as well as complications were reviewed. The maintenance of sagittal balance and rate of fusion were also determined after a minimum of 2 years' follow-up., Summary of Background Data: Posterior correction of scoliosis has been the preferred method of treatment since the introduction of Harrington rods. Recent advances in instrumentation and surgical techniques have allowed surgeons to approach scoliosis correction through the chest and abdomen. These new techniques must be validated before they become accepted alternatives to the standard of care., Methods: One male and 21 female patients, aged 11-18 years, were observed for an average of 44 months. Matched-pairs t tests were used to compare pre- and postoperative curve measurements., Results: Statistically significant curve improvements were seen when postoperative radiographs were compared with preoperative ones. The instrumented coronal plane curve was corrected 82%. A 65% spontaneous correction of the uninstrumented coronal plane curve was observed. Sagittal kyphosis improved 7 degrees, and apical rotation and tilt angles improved 71% and 80%, respectively. A mean loss of 4 degrees of correction was seen on final follow-up radiographs. Lumbar lordosis did not change significantly, and postoperative hyperlordosis was not detected. Ninety-six percent of all instrumented levels fused within 6 months. Although the perioperative complication rate was low, five patients (23%) had asymptomatic idiopathic retrolisthesis develop at the caudal end of the fused vertebrae., Conclusions: Accepted correction of idiopathic scoliosis can be achieved with anterior instrumented fusion alone.

Core decompression for avascular necrosis (AVN) of the femoral head continues to be a controversial procedure. Meta-analysis techniques were employed to identify 22 studies with a single surgical core decompression technique. A similar procedure identified eight studies that treated patients conservatively. The success rates for core decompression were 84%, 63%, and 29% for Steinberg stages I, II, and III, respectively. Conservatively treated patients with stage 0, I, III, and III AVN demonstrated success rates of 86%, 61%, 59%, and 25%, respectively. Chi-square analysis showed the success rate of core decompression to be statistically higher than conservative treatment for stage I hips only. Large multicenter prospective double-blinded studies with patients randomized to either core decompression or conservative treatment, then stratified by stage, cause, and bilaterality, are needed to determine the best treatment for early-stage AVN.

Comparisons between treatments and studies with regard to femoral head osteonecrosis (ON) are difficult because the demographic characteristics of the patients composing the samples vary greatly. The purpose of this investigation was to determine whether ON initiation and progression were specific for a causative agent. A group of 172 patients (245 hips) was subdivided by causative agent. Patients with alcohol-induced ON were significantly older (average age, 49 years; P = .0001), were men (97%), and presented with collapsed femoral heads (90%). Patients with steroid-induced ON averaged 39 years of age, 49% had bilateral disease, and 62% presented with a collapsed femoral head. Patients with idiopathic ON averaged 40 years of age, 35% had bilateral disease, and 55% presented with a collapsed femoral head. Given the different distributions of ON risk factors at initial presentation, it is likely that successful or unsuccessful outcomes may depend most on the sample receiving the intervention. We therefore recommend stratification of patients by causative agent, Steinberg stage at initial presentation, and presence of unilateral or bilateral disease to help clarify the effects of the various treatments for ON of the femoral head.

This study investigated the incidence and clinical significance of postoperative fever in 118 consecutive patients undergoing 141 total knee arthroplasties (TKAs). A postoperative fever was recorded in 63 (66%) of 95 unilateral and 17 (74%) of 23 bilateral TKA patients. Nine of the unilateral and five bilateral TKA patients developed positive clinical or laboratory findings to explain the pyrexia. Unilateral TKA patients who experienced postoperative fever were statistically more likely to have a complication in the immediate postoperative period. None of the surgical variables examined had any predictive value on the incidence of postoperative fever. Aggressive pulmonary toilet, repeated physical examinations, and urine analysis are recommended when evaluating TKA patients with postoperative fever. Fever following TKA was common and was not necessarily a contraindication to discharge.

Thirty-five consecutive patients were evaluated at an average follow-up time of 20 months after circumferential lumbar spinal fusion. All patients had degenerative conditions of the lumbar spine and same-day anterior spinal fusion by using titanium cages packed with autograft bone and posterior instrumentation combined with a posterolateral autogenous bone graft. The purpose of this study was to determine whether anterior titanium cage placement and posterior instrumentation with autologous bone graft was a safe and efficacious procedure in patients with degenerative disease of the lumbar spine. Fusion rates, complications, pain relief, medication use, and work status were specifically analyzed. Although previous reports documented the use of this technique for trauma and tumor cases, few studies assessed clinical and radiographic results in patients with degenerative conditions of the lumbar spine. Plain radiographs were used to determine spinal fusion at each spinal level. All patients were administered preoperative and postoperative questionnaires regarding three specific clinical-outcome parameters. These consisted of pain level, medication use, and work status. Intraoperative and postoperative complications were also documented. Radiographic results showed that 61 (97%) of 63 lumbar levels undergoing an arthrodesis procedure fused either anteriorly, posteriorly, or both. Of the 35 patients in this series, 33 (94%) fused at all levels, and two did not. Substantial pain relief was reported in 46% of all patients. Thirteen (37%) patients had one or more surgical complications. Circumferential spinal fusion in patients with degenerative etiologies yields excellent radiographic fusion rates and good pain relief. The procedure is technically demanding and is associated with a high rate of complications.

A total of 1,717 total hip and 2,769 total knee medical device reports submitted to the U.S. Food and Drug Administration (FDA) from 1984 through 1993 were reviewed. A large percentage of total hip complications could be attributed to some aspect of component modularity. Cementless modular acetabular components were the single largest source of device-related complications. Fifty-six percent of total knee medical device reports (MDRs) were associated with accelerated polyethylene wear. By location, MDRs identified patellar (46%), tibial (33%), and femoral (5%) component complications. It was estimated that less than 5% of device-related complications were reported to the FDA. Based on the reports received, it was apparent that mechanical failure of components was a common and increasing cause of total joint revision.

We prospectively determined the risk of initial stinger experience in a group of college football players while considering the presence of cervical canal stenosis and each player's position, playing time, and body type. Prospective analysis revealed a 7.7% incidence of initial stinger experience. The average Torg ratio for all players was 0.924 +/- 0.122, with the seventh cervical level being the narrowest. Initial stinger experience depended on position played and body type. The Torg ratio did not influence initial stinger occurrence. Players who experienced multiple stingers, however, had significantly smaller Torg ratios than players experiencing only one stinger (0.75 versus 0.87). A Torg ratio of 0.70 may be a more statistically and clinically appropriate threshold for determining significant cervical stenosis and advising collegiate athletes of their risk of experiencing recurrent stingers.