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Little is known about the effect of discontinuation of sealant or fluoride varnish. The purpose of this study was to compare sealant with fluoride varnish in the prevention of occlusal caries in permanent first molars of children over a nine-year period: 4 yrs for program evaluation plus 5 yrs of discontinuation. A clinical trial was conducted on three groups of six- to eight-year-old schoolchildren: a control group (n = 45); a group (n = 37) in which sealant was applied and reapplied up to 36 mos; and a group (n = 38) in which fluoride varnish was applied and re-applied up to 42 mos. Percent caries reduction was studied in these initially healthy molars with complete occlusal eruption: 129 (control), 113 (sealant), and 129 (varnish) molars met inclusion criteria. Of these, 76.7%, 26.6%, and 55.8% had developed occlusal caries at 9 yrs, which implies caries reductions of 65.4% (SE = 8.5%) for sealants vs. control and 27.3% (SE = 10.2%) for varnish vs. control. Furthermore, the varnish program was not effective during the discontinuation period. [ABSTRACT FROM AUTHOR]

We hypothesized that the six-monthly application of silver diamine fluoride (SDF) can arrest the development of caries in the deciduous dentition of six-year-old schoolchildren and prevent caries in their first permanent molars. A prospective controlled clinical trial was conducted on the efficacy of a 38% SDF solution for caries reduction. Four hundred and twenty-five six-year-old children were divided into two groups: One group received SDF solution in primary canines and molars and first permanent molars every 6 mos for 36 mos. The second group served as controls. The 36-month follow-up was completed by 373 children. The mean number of new decayed surfaces appearing in primary teeth during the study was 0.29 in the SDF group vs. 1.43 in controls. The mean of new decayed surfaces in first permanent molars was 0.37 in the SDF group vs. 1.06 in controls. The SDF solution was found to be effective for caries reduction in primary teeth and first permanent molars in schoolchildren. [ABSTRACT FROM AUTHOR]

Because dental fissures may serve as dental reservoirs for mutants and streptococci, preventive measures should be taken to control microbial concentrations at these sites. This study estimated the influence that that sealing permanent first molars would have on the levels of mutants streptococci and lactobacilli in saliva of healthy seven-year-old schoolchildren. Permanent first molars were sealed in 31 children without caries (NC group) and in 32 children with caries (C group). None of the children had caries in their permanent first molars. Conventional methods were used to count mutants in streptococci and lactobacilli in saliva before applying the sealant and again at 4 and 12 weeks after application. Baseline counts of lactobacilli and mutants streptococci were significantly higher in the C group. A significant reduction in mutants streptococci was observed in the NC group at 4 and 12 weeks. It was concluded that fissure sealants in permanent first molars can help reduce salivary levels of mutants streptococci in children without caries. [ABSTRACT FROM AUTHOR]

Early loss of pit and fissure sealants is considered to be primarily dependent on inadequate isolation of the tooth from salivary contamination during application. Gradual additional loss is considered to be caused by occlusal wear, shearing forces, and marginal failure. Our hypothesis is that the caries risk of the child may be an additional factor in sealant loss. The objective of this study was to analyze the influence of caries history in primary teeth (dft index) on the success of sealants. Delton light-polymerized sealant was applied in 104 six- to eight-year-old children, followed for four years on a six-month-visit basis. All sound permanent first molars were sealed during the study. A survival analysis was used to describe sealant success over time. A Cox proportional hazards regression model was built to test the influence on sealant success of the dft index and site of sealant application (mandibular occlusal surface, maxillary fossae, and maxillary disto-lingual fissure), controlling for some potential confounders. Sealant half-life was 46 months. Site and dft index were related to sealant survival. The maxillary fossae showed the best retention, followed by the mandibular occlusal site and the maxillary disto-lingual fissure. The higher the dft, the higher the risk of sealant failure. This study has implications for sealant study designs and public sealant programs. [ABSTRACT FROM AUTHOR]

Background: Mutations of the common cytokine receptor gamma chain (γc) cause Severe Combined Immunodeficiency characterized by absent T and NK cell development. Although stem cell therapy restores these lineages, residual immune defects are observed that may result from selective persistence of γc-deficiency in myeloid lineages. However, little is known about the contribution of myeloid-expressed γc to protective immune responses.  Here we examine the importance of γc for myeloid dendritic cell (DC) function. Methods: We utilize a combination of in vitro DC/T-cell co-culture assays and a novel lipid bilayer system mimicking the T cell surface to delineate the role of DC-expressed γc during DC/T-cell interaction. Results: We observed that γc in DC was recruited to the contact interface following MHCII ligation, and promoted IL-15Rα colocalization with engaged MHCII. Unexpectedly, trans-presentation of IL-15 was required for optimal CD4+T cell activation by DC and depended on DC γc expression. Neither recruitment of IL-15Rα nor IL-15 trans-signaling at the DC immune synapse (IS), required γc signaling in DC, suggesting that γc facilitates IL-15 transpresentation through induced intermolecular cis associations or cytoskeletal reorganization following MHCII ligation. Conclusions: These findings show that DC-expressed γc is required for effective antigen-induced CD4+ T cell activation. We reveal a novel mechanism for recruitment of DC IL-15/IL-15Rα complexes to the IS, leading to CD4+ T cell costimulation through localized IL-15 transpresentation that is coordinated with antigen-recognition., Competing Interests: No competing interests were disclosed.

The aim of this study is to evaluate the concordance between the empirical choice of interdental brushes of different diameters compared to the gold standard, the IAP CURAPROX(©) calibrating colorimetric probe. It is carried out with the aim of facilitating the consensus development of best practices. All the subjects' interproximal spaces were evaluated using the reference technique (colorimetric probe), then after a time lapse of 1.2 ± 0.2 hours, using the empirical clinical technique (brushes) by the same examiner. Each examiner explored 3 subjects. The order the patients were examined with the colorimetric interdental probe (CIP) was random. 446 sites were selected in the study out of 468 potential sites. The correspondence of scores between interdental bushes vs. colorimetric probe is 43.0% [95%-CI: 38.5-47.6]. In 33.41% of the 446 sites, the brush is inferior to the probe; in 23.54% of cases, the brush is superior to the probe. Among the discrepancies there is thus a tendency for the subjects to use brushes with smaller diameter than that recommended by the colorimetric probe. This review has found very high-quality evidence that colorimetric probes plus interdental brushing is more beneficial than interdental brushing alone for increase the concordance between the empirical choice of interdental brushes of different diameters compared to the gold standard. Uncertainties remain and further research is required to provide detailed data on user satisfaction.

The objective of this study was to determine any relationship between oral health-related quality of life (OHR-QoL) and malnutrition risk in the elderly using the oral health impact profile (OHIP). We studied 250 institutionalized elderly people, 162 females and 88 males, with and without teeth. Data were gathered on: general health; oral health; malnutrition risk, measured with the Mini Nutritional Assessment (MNA); and OHR-QoL, evaluated with the OHIP. A multivariate binary logistic regression model was constructed with malnutrition presence/risk as dependent variable. Mean age was 82.7 ± 8.2 years. Malnutrition or malnutrition risk was shown by 36.8% of the sample. OHIP was associated with malnutrition/risk after adjustment for age, sex, functional status, and mild dementia diagnosis. Malnutrition/risk was 3.43-fold more likely in participants with OHIP-reported "problems" than in those with none. The conclusion of the study was that OHIP-measured OHR-QoL is associated with malnutrition risk., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

The relationship between intermembrane spacing, adhesion efficiency, and lateral organization of adhesion receptors has not been established for any adhesion system. We have utilized the CD2 ligand CD48 with two (wild type CD48 (CD48-WT)), four (CD48-CD2), or five (CD48-CD22) Ig-like domains. CD48-WT was 10-fold more efficient in mediating adhesion than CD48-CD2 or CD48-CD22. Electron tomography of contact areas with planar bilayers demonstrated average intermembrane spacing of 12.8 nm with CD48-WT, 14.7 nm with CD48-CD2, and 15.6 nm with CD48-CD22. Both CD48-CD2 and CD48-CD22 chimeras segregated completely from CD48-WT in mixed contact areas. In contrast, CD48-CD2 and CD48-CD22 co-localized when mixed contacts were formed. Confocal imaging of immunological synapses formed between primary T lymphocytes and Chinese hamster ovary cells presenting major histocompatibility complex-peptide complexes, and different forms of CD48 demonstrated that CD48-CD2 and CD48-CD22 induce an eccentric CD2/T cell antigen receptor cluster. We propose that this reorganization of the immunological synapse sequesters the T cell antigen receptor in a location where it cannot interact with its ligand and dramatically reduces T cell sensitivity.

Monocytes participate critically in atherosclerosis. There are 2 major subsets expressing different chemokine receptor patterns: CCR2(+)CX3CR1(+)Ly-6C(hi) and CCR2(-)CX3CR1(++)Ly-6C(lo) monocytes. Both C-C motif chemokine receptor 2 (CCR2) and C-X(3)-C motif chemokine receptor 1 (CX3CR1) are linked to progression of atherosclerotic plaques. Here, we analyzed mouse monocyte subsets in apoE-deficient mice and traced their differentiation and chemokine receptor usage as they accumulated within atherosclerotic plaques. Blood monocyte counts were elevated in apoE(-/-) mice and skewed toward an increased frequency of CCR2(+)Ly-6C(hi) monocytes in apoE(-/-) mice fed a high-fat diet. CCR2(+)Ly-6C(hi) monocytes efficiently accumulated in plaques, whereas CCR2(-)Ly-6C(lo) monocytes entered less frequently but were more prone to developing into plaque cells expressing the dendritic cell-associated marker CD11c, indicating that phagocyte heterogeneity in plaques is linked to distinct types of entering monocytes. CCR2(-) monocytes did not rely on CX3CR1 to enter plaques. Instead, they were partially dependent upon CCR5, which they selectively upregulated in apoE(-/-) mice. By comparison, CCR2(+)Ly-6C(hi) monocytes unexpectedly required CX3CR1 in addition to CCR2 and CCR5 to accumulate within plaques. In many other inflammatory settings, these monocytes utilize CCR2, but not CX3CR1, for trafficking. Thus, antagonizing CX3CR1 may be effective therapeutically in ameliorating CCR2(+) monocyte recruitment to plaques without impairing their CCR2-dependent responses to inflammation overall.

We investigated the fate of latex (LX) particles that were introduced into mice intranasally. Macrophages acquired the vast majority of particles and outnumbered LX particle-bearing airway dendritic cells (DCs) by at least two orders of magnitude. Yet alveolar macrophages were refractory to migration to the draining lymph node (DLN), and all transport to the DLN could be ascribed to the few LX(+) airway DCs. Upon macrophage depletion, markedly greater numbers of DCs were recruited into the alveolar space. Consequently, the number of DCs that carried particles to the DLN was boosted by 20-fold. Thus, a so far overlooked aspect of macrophage-mediated suppression of airway DC function stems from the modulation of DC recruitment into the airway. This increase in DC recruitment permitted the development of a robust assay to quantify the subsequent migration of DCs to the DLN. Therefore, we determined whether lung DCs use the same molecules that skin DCs use during migration to DLNs. Like skin DCs, lung DCs used CCR7 ligands and CCR8 for emigration to DLN, but the leukotriene C(4) transporter multidrug resistance-related protein 1 did not mediate lung DC migration as it does in skin, indicating that pathways governing DC migration from different tissues partially differ in molecular regulation.

We previously demonstrated that L-selectin (CD62L)-dependent T cell homing to lymph nodes (LN) is required for tolerance induction to alloantigen. To explore the mechanisms of this observation, we analyzed the development and distribution of regulatory T cells (Treg), which play an important protective role against allograft rejection in transplantation tolerance. Alloantigen-specific tolerance was induced using either anti-CD2 plus anti-CD3 mAbs, or anti-CD40L mAbs plus donor-specific transfusion, in fully mismatched (BALB/c donor, C57BL/6 recipient) vascularized cardiac allografts. An expansion of CD4(+)CD25(+)CD62L(high) T cells was observed specifically within the LN of tolerant animals, but not in other anatomic sites or under nontolerizing conditions. These cells exhibited a substantial up-regulation of Foxp3 expression as measured by real-time PCR and by fluorescent immunohistochemistry, and possessed alloantigen-specific suppressor activity. Neither LN nor other lymphoid cells expressed the regulatory phenotype if recipients were treated with anti-CD62L mAbs, which both prevented LN homing and caused early allograft rejection. However, administration of FTY720, a sphingosine 1-phosphate receptor modulator that induces CD62L-independent T cell accumulation in the LNs, restored CD4(+)CD25(+) Treg in the LNs along with graft survival. These data suggest that alloantigen-specific Foxp3(+)CD4(+)CD25(+) Treg develop and are required within the LNs during tolerization, and provide compelling evidence that distinct lymphoid compartments play critical roles in transplantation tolerance.

Objective: The aim of this study was to determine the separate effects of dental sealants and fluoride varnish on dental caries in fissured and nonfissured surfaces of permanent first molars., Methods: A clinical trial was conducted with three groups of 6- to 8-year-old schoolchildren: a sealant group (n = 100), in which Delton was applied to first molars; a varnish group (n = 98), in which Duraphat was applied to first molars; and a control group (n = 116), which had no intervention as part of the study. Absolute and percent caries reductions were compared at 24 months., Results: Compared to the controls, sealants resulted in a 68 percent and 87 percent reduction on fissured and nonfissured surfaces, respectively. The corresponding figures for varnish were 38 percent and 66 percent., Conclusion: Sealant and fluoride varnish are effective in preventing caries in both fissured and nonfissured surface.

The objective of this study was to compare Delton visible-light fissure sealant with Duraphat fluoride varnish in the prevention of occlusal caries in permanent first molars. A 48-month clinical trial was carried out in three groups of 6- to 8-year-old schoolchildren: a sealant group (104 children), in which Delton was used; a varnish group (112 children), in which Duraphat was used; and a control group (128 children). Sealant or varnish was applied to all sound permanent first molars, according to group. Replacement (sealant) and reapplication (varnish) was carried out every 6 months. A survival analysis was used to describe the molar failures over time in the three groups. A Cox proportional hazards regression model was built to test the influence of group on molar failure. The median survival times were 28.6 months for the control molars and more than 48 months for both sealed and varnished molars. The Cox model indicated a hazard ratio of 0.177 for the sealant vs control comparison, 0.463 for varnish vs control and 0.382 for sealant vs varnish.

The present study compares visible-light Delton with Duraphat fluoride varnish for the prevention of occlusal caries in permanent first molars. A clinical trial was carried out in three groups of 6-8-yr-old schoolchildren: a sealant group (100 children), in which Delton light-polymerized fissure sealant was applied to permanent first molars; a varnish group (98 children), in which Duraphat was applied to permanent first molars; and a control group (116 children). Replacement (sealant) and reapplication (varnish) was carried out every 6 months. Percent effectiveness at 24 months (percentage of saving from caries taking molars as analysis unit) for those molars initially healthy and with complete occlusal eruption was analyzed. 272, 252 and 238 molars met the inclusion criteria in the control, varnish and sealant groups, respectively. Of these, 45.2%, 28.2% and 10.5% developed caries after 24 months. The effectiveness was greater in the sealed molars than in the varnished molars (62.7%).

Meta-analysis of published studies was applied to analyze the effectiveness of fissure sealants in preventing dental caries. Studies were identified by a MEDLINE search, supplemented by a hand search of the references in the articles recovered. All articles were assessed on the basis of quality, and were combined with the Mantel-Haenszel method. The prevented fraction in the exposed population (PF) was estimated using pooled relative risk. Heterogeneity of the effect and publication bias were also analyzed. Twenty-four studies were included in the meta-analysis. The overall effectiveness of autopolymerized fissure sealants was 71.36% (95% confidence interval 69.69-72.94%). Effectiveness in preventing caries decreased with time, and increased when drinking water was fluoridated (82.69% vs 72.28%). Heterogeneity was significant in most cases, and was further studied with multiple linear regression analysis. It is concluded that autopolymerizing sealants should be used. More research is needed to compare the effectiveness of dental hygienists and dentists in applying sealants.