Lower Fixed Retainers: Bonded On All Teeth Or Only On Canines? A Systematic review

ObjectiveTo evaluate the stability after orthodontic treatment between two types of lower fixed retainers: those bonded onto all anterior teeth or those bonded only onto the canines.Materials and MethodsThe following electronic databases were consulted: PubMed, Scopus, Web of Science, Cochrane Library, Lilacs, OpenGrey, ClinicalTrials, and Google Scholar. No restriction of language or year were applied. After selection of studies, risk-of-bias evaluation and qualitative synthesis of the included studies were performed using The Cochrane Collaboration''s tool for randomized studies and the “Risk of Bias in Non-randomized Studies of Interventions” (ROBINS-I) tool for nonrandomized studies, and a summary of the overall strength of evidence was presented using the “Grading of recommendations, assessment, development and evaluation” tool.ResultsAmong the 180 studies retrieved from the searches, five were included in this review. Three of them showed a low risk of bias, while two presented a high risk of bias. With regard to stability, two studies reported better stability for retainers bonded to all six teeth, while the other three showed no difference. The retainer bonded to all teeth presented a higher breakage rate in one study.ConclusionsStability seems better with lower fixed retainers bonded on all anterior teeth. The breakage rate may not change according to the bonding. However, studies with greater methodological soundness are necessary to reach a more reliable conclusion.     

Effects of a full-mouth disinfection protocol on the treatment of type-2 diabetic and non-diabetic subjects with mild-to-moderate periodontitis: one-year clinical outcomes

Clinical Oral Investigations - This study compared the clinical effects of a full-mouth disinfection (FMD) protocol for the treatment of mild-to-moderate periodontitis in type 2 diabetic and...     

Hepatitis B virus prevalence and vaccination response in health care workers and students at the Federal University of Bahia, Brazil

Background and rationale for the study. Hepatitis B (HB) is one of the most prevalent occupational infections in health attendance environments. According to the Brazil Ministry of Health, health professionals must be vaccinated against the hepatitis B virus (HBV) and provide laboratory proof of immunization. Aims. To evaluate the seroprevalence of HBV infection and to analyze the response to vaccine by measuring serum antibodies against HBV surface antigen (anti-HBs) levels in a sample of students and health professionals at the Federal University of Bahia.Results. As part of this cross-sectional study, a campaign against occupational HB was launched in 2007 and vaccination and blood samples were collected for analysis of the following serological markers: HBV surface antigen (HBsAg) and anti-HBs (measured by enzyme-linked immunoassay) and total antibodies against HBV core antigen (anti-HBc). The study sample comprised 766 people. Global seropositivity for HBV was 1.7%: 0.5% in the students and 8.8% in the professionals. In a group of volunteers, a serological profile compatible with postvaccine immunity was shown by 95% of volunteers with proof of vaccination and by 81.8% of volunteers without proof of vaccination. Conclusions. In conclusion, this study shows that it is important to promote vaccination campaigns and improve knowledge and awareness about HB among health care workers and higher education students.     

Comparative study of pinocytosis and the production of prostaglandin E2 by hepatic and peritoneal resident macrophages in mice

Pinocytosis and prostaglandin E2 production are two major functions of the mononuclear phagocyte system. The goal of this study was to compare the pinocytosis of horseradish peroxidase and the prostaglandin E2 production between the hepatic and peritoneal resident macrophages in the mouse. Hepatic resident macrophages were isolated by collagenase digestion, differential centrifugation and adherence. Peritoneal resident macrophages were isolated by peritoneal cavity washing followed by adherence. Horseradish peroxidase was endocytosed by hepatic macrophages at a significantly higher rate (118 +/- 12 ng/10(6) cells/60 min) than by peritoneal macrophages (21 +/- 4 ng/10(6) cells/60 min). Prostaglandin E2 production was measured in the culture medium of unstimulated and lymphokine-stimulated hepatic and peritoneal resident macrophages. Prostaglandin E2 concentration in the culture medium of unstimulated peritoneal macrophages was 36.6 +/- 26.8 ng/ml after a 24 h incubation. It was increased by 83 p. 100 in presence of a lymphokine-enriched secondary mixed lymphocyte culture supernatant. In contrast, hepatic macrophages did not produce any significant amount of prostaglandin E2, even if they were incubated in presence of lymphokines. This study shows that hepatic resident macrophages have a higher pinocytic capacity than peritoneal resident macrophages, suggesting that the role of the liver in the clearance of gut-derived antigens is not only due to its portal irrigation but also to the presence of macrophages highly differentiated in their endocytotic properties. The lack of prostaglandin E2 production in hepatic macrophages, in basal conditions as well as after lymphokine-stimulation, suggests that these cells play a minor role in the regulation of the immune response.(ABSTRACT TRUNCATED AT 250 WORDS)     

Corticotropin-releasing hormone-containing neurons in the hypothalamo-hypophyseal system in rats six weeks after bilateral lesions of the paraventricular nucleus

Adenosine is now considered as a major regulatory agent in the mammalian central nervous system. Its actions are mediated by specific receptors which are coupled with an adenylate cyclase system via a G protein. The postnatal development of adenosine A₁ receptors was studied by quantitative autoradiography using [³H]N⁶-cyclohexyladenosine, a potent receptor agonist in 42 rat brain structures. The coupling of these sites to G proteins was examined by measuring the effects of in vitro addition of guanylyl-5′-imidodiphosphate, a stable analogue of guanosine triphosphate, on N⁶-cyclohexyladenosine binding. [³H]N⁶-Cyclohexyladenosine-specific binding was quite low at birth, around 10% of adult levels, and exhibited a rather homogeneous distribution pattern, except in thalamic nuclei. Data showed a sequential development of adenosine A₁ receptors in relation to the time course of maturation of cerebral structures with a proliferation peak which paralleled rapid brain growth.

The time period by which adult levels are reached differed according to the cerebral region studied. N⁶-Cyclohexyladenosine-specific binding sites appeared to be functionally linked to G proteins in all structures and at all postnatal stages. However, the potency of guanylyl-5′-imidodiphosphate to displace N⁶-cyclohexyladenosine binding was significantly lower before 5 days of age, suggesting functional changes during postnatal maturation in cerebral pathways modulated by adenosine.     

Risk factors for death caused by pneumonia in children younger than 1 year old in a metropolitan region of southeastern Brazil. A case- control study]

In a case-control study, a sample of post-neonatal deaths from pneumonia occurring in the Metropolitan Area of Rio de Janeiro, Brazil (1986-1987) were compared with healthy controls who lived in the same neighborhood. Risk factors investigated were variables related to the mother's pregnancy history and the child's birth, to the family's social condition and to the use of health services. Using the univariate logistic regression model, the coefficients of each independent variable, the relative risk and its confidence limits were first estimated. Birth weight and age of weaning were strongly associated with the dependent variable. After adjustment by means of the multiple logistic regression model, only 4 variables remained statistically associated with mortality: age of weaning, birth weight, over crowding, and BCG vaccination. Based on the available data, it was concluded that mortality from pneumonia in children under 1 year of age is significantly related to the social condition of the family, particularly to that of the mother.     

Epidemiology of visceral leishmaniasis in northeast Brazil.

Epidemiologic aspects of the relationship between infection with Leishmania chagasi and development of clinical visceral leishmaniasis (VL) were studied in all children < 11 years old in a defined, endemic, rural area of the state of Ceará in northeast Brazil. Antileishmanial antibodies were measured in the same subjects by ELISA on six occasions between May 1987 and August 1989. Seroconversion was documented during this period in 108 children, with a cumulative annual incidence of 4.6%. Twelve (11.1%) of these children developed VL. Age < 4 years, hematocrit < 33%, and living in the mountains predicted the development of clinically apparent VL after seroconversion. Despite a high percentage of dogs serologically positive in the region (38%), there was no increased risk of infection for children living in the same household with dogs. Since children in households with a prior case of VL had a threefold increased risk of infection, human-sandfly-human transmission might have been important.     

Blood lead levels in pregnant women of high and low socioeconomic status in Mexico City.

This study examined the determinants of blood lead (BPb) in 513 pregnant women in Mexico City: 311 from public hospital prenatal clinics, representing primarily women of low socioeconomic status (SES), and 202 from private hospitals, primarily women of high SES. Overall, BPb levels ranged from 1.38 to 29 micrograms/dl, with geometric means of 6.7 and 11.12 micrograms/dl for women from private and public hospitals, respectively. The crude geometric means difference obtained by t-test was 4.42 (p < 0.001). BPb was measured from January 1994 to August 1995 and showed higher levels during fall and winter and lower levels during spring and summer. The main BPb determinants were the use of lead-glazed ceramics in women from public hospitals and season of the year in women from private hospitals. Consumption of tortillas (corn bread rich in calcium) decreased BPb levels in the lower SES group, but the relationship was not statistically significant (p > 0.05). Consumption of milk products significantly (p < 0.05) reduced BPb levels in the higher SES group. In 112 women whose diets were deficient in calcium, taking calcium supplements lowered their blood lead levels about 7 micrograms/dl. A predictive model fitted to these data, using the strongest predictors plus gestational age, showed a difference of 14 micrograms/dl between the best and worst scenarios in women from public hospitals. Avoiding use of lead-glazed ceramics, consuming diets rich in calcium, and, if needed, taking calcium supplements, would be expected to result in substantial lowering of BPb, especially in pregnant women of low socioeconomic status.