Impact of sexual maturity on the welfare of immunocastrated v. entire heavy female pigs.

During oestrus, fattening female pigs are more prone to lameness, fractures and wounds due to mounting and agonistic behaviours of penmates. This study assessed the effect of sexual maturity on the behaviour and welfare of heavy female pigs slaughtered at 36 weeks of age (180±10 kg) for dry-cured ham production. An immunocastrated control group was used for comparison. In all, 56 15-week-old female pigs, individually identifiable by back tattoos were equally distributed among four pens. All animals from two pens were subject to a three-dose immunocastration schedule at 16, 20 and 32 weeks of age. Skin lesions and behaviours were assessed at 18, 23, 28, 33 and 36 weeks of age. A blood sample was collected at 20, 24, 28 and 32 weeks of age for assessing health/stress parameters and GnRH antibodies. At slaughter, ovaries were weighed, measured and histologically examined; stomachs, carcasses and lungs were scored for lesions and a further blood sample was taken. Immunocastrated pigs did not significantly differ from controls in growth rate, feed efficiency and slaughter performances (lung score, gastric score, backfat thickness). However, they showed a lower frequency of aggressive interactions at 33 and 36 weeks, lower front lesions at 28 weeks, but higher at 30 weeks; a lower haptoglobin level at 28 weeks, a lower level of cortisol and back lesions at slaughter (36 weeks). These findings suggest a low, yet not negligible, impact of sexual maturity on the welfare of heavy female pigs.

The development of medical-manager roles in European hospital systems: a framework for comparison.

A central motif of health reforms around the world has been the drive to persuade doctors and other clinical professionals to become more actively engaged in the management of services. Examples include moves to extend the commissioning role of primary care doctors (such as general practitioners in the UK) and the introduction of 'clinical directorates' in secondary care. This strategy has been seen as a means of controlling professionals, turning 'poachers into game keepers', especially with regard to resource allocation. However, there is also a mounting body of evidence pointing to how clinical leadership may play a role in stimulating quality improvement and new innovations inservice design, with positive consequences for patient safety and satisfaction (1). Focusing on the top 100 hospitals in the US Goodall (2) finds a strong positive association between the ranked quality of hospitals and whether the chief executive officer was a clinician. A survey of 1200 hospitals across seven countries (UK, US, Germany, France, Italy,Canada and Sweden) conducted by McKinsey and LSE also finds that clinically qualified managers improve both the effectiveness of management decisions and clinical performance of hospitals overall (3).

Cariostatic effect and fluoride release from a visible light-curing adhesive for bonding of orthodontic brackets.

This study was designed to investigate the cariostatic potential in vivo of a visible light-curing adhesive for the bonding of orthodontic brackets. The fluoride release of the adhesive in water and saliva was also measured. Ten orthodontic patients with premolars to be extracted participated. One bracket with Heliosit-Orthodontic (no fluoride) was positioned on the buccal surface of one premolar (control), and another bracket with Orthodontic cement VP 862 (containing fluoride) was positioned on the experimental contralateral premolar. The adhesives were cured with a Heliolux II lamp, and the teeth were extracted after 4 weeks. The patients used a fluoride toothpaste during the experiment. The mineral content of the enamel adjacent to the brackets was determined by quantitative microradiography. The fluoride release from disk-shaped plates of the fluoride adhesive was measured in water for a 6-month period and in human saliva for 24 hours. The fluoride adhesive reduced lesion depths by about 48% than the nonfluoride adhesive (P less than 0.05, t test). The largest release of fluoride from the plates in water was observable within the first week. However, a significant amount of fluoride was still released after 6 months. The fluoride release in saliva was significantly lower in human saliva at pH 7 than in water (P less than 0.01, t test). When salivary pH was lowered to 4, to mimic a cariogenic challenge, the amount of fluoride released increased up to the value measured in water. It was concluded that the regular use of fluoride toothpastes is insufficient to inhibit lesion development around orthodontic brackets.(ABSTRACT TRUNCATED AT 250 WORDS)

Tensile bond force of glass ionomer cements in direct bonding of orthodontic brackets: an in vitro comparative study.

Tensile bond force of three glass ionomers was evaluated in vitro. Ketac-Cem and Aqua-Cem, two conventional cements, and light-cured Vitrabond were used in this study. The results were then compared with the values obtained for a composite resin (Concise) by means of the Mann-Whitney two-sample rank test adjusted for ties. The composite resin had a significantly higher bond force (152.5 N) than any of the other adhesives (5.5 to 27.53 N) used. Tensile bond strength was also calculated and the failure bond site investigated on the enamel surface was evaluated. The composite resin and the two conventional glass ionomers used had high cement percentages (86% to 62%) adhering to the enamel surface. Cement remaining on enamel was lower (20%) for the light-cured glass ionomer. It was concluded that the in vitro bond force of Vitrabond might be adequate for orthodontic bracket bonding.

An in vivo study on the merits of two glass ionomers for the cementation of orthodontic bands.

The purpose of this study was to investigate the cariostatic effect of two glass ionomer cements on in vivo demineralization of partly uncovered enamel beneath orthodontic bands. A 4-week clinical trial was conducted on a group of five patients with nine pairs of premolars to be extracted for orthodontic purposes. Specially designed orthodontic bands were cemented with either Ketac-Cem (K-C) or Aqua-Cem (A-C). A local cariogenic milieu was created between the buccal surface of the premolars and the inner surface of the bands to secure plaque accumulation. The mineral content of the teeth was quantified by microradiography. The data were compared with data from a previous study of patients in the same age group with bands that had been cemented with a non-F cement. After comparison with the non-F group, the lesion depth (ld) was reduced by 63% for K-C and by 55% for A-C. This reduction was statistically significant at the 2.5% level (t test). The total mineral loss in teeth cemented with glass ionomer cements (delta Z) was reduced, in comparison with the loss in teeth cemented with non-F cement, by 49% with K-C and by 27% with A-C. The differences were statistically significant only for the K-C group (t test, p less than 0.025). There were no significant differences between the two glass ionomer cements with respect to either lesion depth or total mineral loss values (paired t test; p greater than 0.05). This investigation shows that fluoride released from glass ionomer cements contributes substantially to demineralization "reduction." However, these cements do not provide complete caries protection in sites where access is difficult.

Availability of fluoride from glass-ionomer luting cements in human saliva.

Fluoride availability from two glass-ionomer luting agents, Ketac-Cement and Aqua-Cement, was monitored after a 1-h treatment in distilled water at pH 7. The recorded results were then compared to the ones obtained from those same cements, after 1 h, in saliva, in water pretreated with saliva (pH 7 and 4.5), and in albumen and phosphate buffer solutions (pH 7). The Mann-Whitney two-sample rank test was utilized in order to identify the differences. The presence of proteins and phosphate reduced fluoride availability. A reduction in the pH from 7 to 4.5 resulted in an increased rate of fluoride release, in water, from glass-ionomers pretreated with saliva. The present study indicates that fluoride availability from glass-ionomers, in vivo, is pH controlled. The rate controlling factors appear to be phosphate and proteins.