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Human exposure to contaminated soils drives clean up criteria at many urban brownfields. Current risk assessment guidelines assume that humans ingest some fraction of soil smaller than 4 mm but have no estimates of what fraction of soil is ingested by humans. Here, we evaluated soil adherence to human hands for 13 agricultural soils from Saskatchewan, Canada and 17 different soils from a brownfield located in Iqaluit, Nunavut, Canada. In addition, we estimated average particle size adhering to human hands for residents of a northern urban setting. Further, we estimated how metal concentrations differed between the adhered and bulk (< 4 mm) fraction of soil. The average particle size for adhered agricultural soils was 34 microm, adhered brownfield soils was 105 microm, and particles adhered to human residentswas 36 microm. Metals were significantly enriched in these adhered fractions with an average enrichment [(adhered-bulk)/bulk] in metal concentration of 184% (113% median) for 24 different elements. Enrichment was greater for key toxicological elements of concern such as chromium (140%), copper (140%), nickel (130%), lead (110%), and zinc (130%) and was highest for silver (810%), mercury (630%), selenium (500%), and arsenic (420%). Enrichment were positively correlated with carbonate complexation constants (but not bulk solubility products) and suggests that the dominant mechanism controlling metal enrichment in these samples is a precipitation of carbonate surfaces that subsequently adsorb metals. Our results suggest that metals of toxicological concern are selectively enriched in the fraction of soil that humans incidentally ingest. Investigators should likely process soil samples through a 45 microm sieve before estimating the risk associated with contaminated soils to humans. The chemical mechanisms resulting in metal enrichment likely differ between sites but at our site were linked to surface complexation with carbonates.

Modifying poultry diets by reducing mineral P supplementation and/or adding phytase may change the chemical composition of P in manures and affect the mobility of P in manure-amended soils. We studied the speciation of P in manures produced by broiler chickens and turkeys from either normal diets, or diets with reduced amounts of non-phytate phosphorus (NPP) and/or phytase, using a combination of chemical fractionation and synchrotron X-ray absorption near edge structure (XANES) spectroscopy. All broiler litters were rich in dicalcium phosphate (65-76%), followed by aqueous phosphate (13-18%), and phytic acid (7-20%); however, no hydroxylapatite was observed. Similarly, normal turkey manure had 77% of P as dicalcium phosphate and had no hydroxylapatite, while turkey manure from diets that had reduced NPP and phytase contained equal proportions of dicalcium phosphate (33-45%) and hydroxylapatite (35-39%). This is attributed to the higher total Ca to P ratio (>2) in modified turkey manures that resulted in transformation of more soluble (dicalcium phosphate) to less soluble P compounds (hydroxylapatite). Chemical fractionation showed that H2O-extractable P was the predominant form in broiler litter (56-77%), whereas aqueous phosphate determined with XANES was <18% indicating that H2O probably dissolved mineral forms of P (e.g., dicalcium phosphate). Results show that HCl extraction primarily removed phytic acid from broiler litters and normal turkey manure, while it removed a mixture of hydroxylapatite and phytic acid from modified turkey manures. The combination of chemical fractionation and XANES provided information about the nature of P in these manures, which may help to devise best management practices for manure use.

Objective: The objective of this study was to investigate the outcome of conventional root canal treatment in a general practice setting within the Royal Air Force dental service. Design Retrospective review., Methods: Teeth that had been root-filled for 12 months or more by Royal Air Force dental practitioners in patients attending a large Royal Air Force dental centre were included in the study. Following clinical and radiographic review the root fillings were classified as 'definitely successful', 'probably successful' or 'failed' The effect on success of several variables on the outcome was investigated., Results: Out of a total of 406 teeth, 59% were maxillary teeth and 41% were mandibular teeth. Sixty-nine per cent of the total sample had pre-existing periapical radiolucencies. Cold lateral condensation of gutta-percha was the most widely used filling technique (64% of all cases). Fifty per cent of the teeth had root fillings within 2 mm of the radiographic apex, 32% were greater than 2 mm from the radiographic apex and 18% were overfilled. Cold lateral condensation was the most successful (92% overall) filling technique. Maxillary anterior teeth had a better success rate (96%) than other tooth types. Teeth with pre-existing periapical radiolucencies had a higher success rate (87%) than those cases where there was no pre-existing periapical radiolucency (80%). Root fillings that were less than 2 mm from the radiographic apex of the tooth had a higher success rate (88% overall) than those that were greater than 2 mm from the radiographic apex (77% overall). Of the 406 cases, 57% (n=231) were classified as definitely successful, 28% (n=114) were classified as probably successful and 15% (n=62) were classified as failures. Thus, the overall success rate combining definitely successful and probably successful root fillings was 85% (n=344)., Conclusions: Root fillings placed using cold lateral condensation of gutta-percha to within 2 mm of the radiographic apex of the tooth were associated with the best outcome.

We describe a case in which a patient with a class II division I incisor relationship on a skeletal II base was transferred midway through a treatment that consisted of aligning the upper and lower arches with fixed appliance orthodontics in preparation for a mandibular advancement osteotomy. The lower second molars had previously been extracted; the lower third molars were left unerupted and some distance from the lower first molars. To provide a good occlusion at the end of treatment, it was decided to expose and approximate the lower third molars to the distal aspect of the lower first molars with the use of nickel titanium closed-coil springs; this was to be done before the osteotomy.

Violent crime has become a public health issue, not least because the needs of victims have been neglected in the criminal justice system. Since this group suffer more psychological distress than victims of accidents, we compared illness experience in 433 adult assault victims with paired victims of accidents in a case control study. In the 10 year period prior to injury, there was a significant excess of hospital contacts in the assault group in relation to trauma, elective surgery and drug abuse but not to other psychiatric or medical conditions. This spectrum of disorders constitutes a previously unrecognized syndrome in young adults, probably representing the manifestations of antisocial personality.

Purpose: To assess the success of orthograde endodontic treatment carried out by a group of general dental practitioners over a 15-year period., Population Studied: Patients presenting for their annual dental inspection at a large Air Force station in the UK over a six-month period. All teeth root-filled by Royal Air Force dental practitioners were assessed., Method: Clinical and, where appropriate, radiographic review was undertaken of all root-filled teeth present at inspection. Root-filled teeth removed prior to inspection were included in the study only if extraction was related to failure of the root filling. Root fillings were classified as 'definitely successful', 'probably successful' or 'failed'. The effect on success of several variables was investigated., Findings: There was a total of 136 root-filled teeth, of which 59% (n=80) were classified as 'definitely successful', 26% (n=35) as 'probably successful', and 15% (n=21) as failures. Of the variables studied, only time elapsed since root-filling placement had a statistically significant effect on treatment results with a downward trend in rate of failure with time (P=0.0268)., Conclusions: An overall success rate of 85% was found for this sample of root fillings comparing well with the success rates for root fillings placed by specialists. However, there may be significant differences in the relative importance of clinical variables depending on the experience of the operator. There are few reliable indicators of the likely prognosis for the root filling, questioning the automatic replacement of poor technical quality, but asymptomatic root fillings.

Inflammation resulting from any form of tissue injury causes an increase in plasma concentration of a number of liver-derived proteins (the acute phase reactant proteins), the measurement of which provides an indication of the magnitude of the inflammatory response. C reactive protein (CRP) is an example of an acute phase protein. Although concentrations increase particularly dramatically in response to inflammation and reflect the degree of ongoing tissue damage, this method has yet to be used to assess severity of injury in traumatology and forensic medicine. The rate at which the acute phase protein response occurred after injury was therefore explored in a series of 16 patients with maxillofacial skeletal injuries and in a series of 22 age- and sex-matched control patients. Increases in the plasma concentration of CRP were not detected until 6-12 h after injury and peaked at 48-72 h. Concentration of CRP was less than 10 mgm/l in all control patients. There was significant relation between peak levels and Abbreviated Injury Scale and Injury Severity scores. Results suggest that this method of assessing the severity of traumatic injury deserves further investigation and may be of use clinically, medico-legally and in relation to compensation awards.