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Background & Aims The role of tobacco smoke in the etiology of inflammatory bowel disease (IBD) is unclear. We investigated interactions between genes and smoking (gene−smoking interactions) that affect risk for Crohn’s disease (CD) and ulcerative colitis (UC) in a case-only study of patients and in mouse models of IBD. Methods We used 55 Immunochip-wide datasets that included 19,735 IBD cases (10,856 CD cases and 8879 UC cases) of known smoking status. We performed 3 meta-analyses each for CD, UC, and IBD (CD and UC combined), comparing data for never vs ever smokers, never vs current smokers, and never vs former smokers. We studied the effects of exposure to cigarette smoke in Il10 −/− and Nod2 −/− mice, as well as in Balb/c mice without disruption of these genes (wild-type mice). Mice were exposed to the smoke of 5 cigarettes per day, 5 days a week, for 8 weeks, in a ventilated smoking chamber, or ambient air (controls). Intestines were collected and analyzed histologically and by reverse transcription polymerase chain reaction. Results We identified 64 single nucleotide polymorphisms (SNPs) for which the association between the SNP and IBD were modified by smoking behavior (meta-analysis Wald test P < 5.0 × 10 −5 ; heterogeneity Cochrane Q test P > .05). Twenty of these variants were located within the HLA region at 6p21. Analysis of classical HLA alleles (imputed from SNP genotypes) revealed an interaction with smoking. We replicated the interaction of a variant in NOD2 with current smoking in relation to the risk for CD (frameshift variant fs1007insC; rs5743293). We identified 2 variants in the same genomic region (rs2270368 and rs17221417) that interact with smoking in relation to CD risk. Approximately 45% of the SNPs that interact with smoking were in close vicinity (≤1 Mb) to SNPs previously associated with IBD; many were located near or within genes that regulate mucosal barrier function and immune tolerance. Smoking modified the disease risk of some variants in opposite directions for CD vs UC. Exposure of Interleukin 10 (il10)-deficient mice to cigarette smoke accelerated development of colitis and increased expression of interferon gamma in the small intestine compared to wild-type mice exposed to smoke. NOD2-deficient mice exposed to cigarette smoke developed ileitis, characterized by increased expression of interferon gamma, compared to wild-type mice exposed to smoke. Conclusions In an analysis of 55 Immunochip-wide datasets, we identified 64 SNPs whose association with risk for IBD is modified by tobacco smoking. Gene−smoking interactions were confirmed in mice with disruption of Il10 and Nod2 —variants of these genes have been associated with risk for IBD. Our findings from mice and humans revealed that the effects of smoking on risk for IBD depend on genetic variants. [ABSTRACT FROM AUTHOR]

Objectives: Endodontically treated teeth (ETT) used as abutments for removable partial dental prostheses (RPDPs) have an increased fracture risk as compared to vital abutments. One suggested explanation is that ETT exhibit a lower threshold level for tactile sensitivity than vital teeth. Therefore, this study compared the threshold for tactile sensitivity of vital teeth and ETT in the same individuals. Methods: Forty participants with double crown-retained RPDPs fixed to vital teeth and ETT were included in the study. Each subject had at least one vital and one corresponding contralateral endodontically treated abutment tooth in the same jaw. After removal of the RPDP, an increasing centric force (0 cN to max. 2000 cN) was separately applied axially to both free-standing abutment teeth using a force gauge while the patient was asked to give three acoustic signals: (1) when noticing the first contact, (2) when noticing pressure and (3) when the pressure became displeasing. Afterwards, the same trial was performed with an eccentric force applied parallel to the tooth axis. Results: Statistical analysis revealed no significant differences in the threshold of tactile sensitivity of vital teeth and ETT to either centric or eccentric loading (p > 0.05). Eccentric loading showed lower mean threshold values compared to centric loading. A large variability of tactile sensitivity between individuals was noted. However, there were no gender-related significant differences in tactile sensitivity (p > 0.05). Conclusions: The tactile sensitivity of vital and non-vital teeth seems comparable. Clinical significance: The assumption that a lower threshold level for tactile sensitivity in ETT than in vital teeth is responsible for their increased fracture risk could not be confirmed. Therefore, other reasons, e.g. loss of hard tissue due to root canal treatment, have to be considered responsible for the increased fracture risk of ETT. [ABSTRACT FROM AUTHOR]

This study aimed to demonstrate the effect of treating titanium-implant surfaces with plasma from two different sources on wettability and initial single-cell adhesion of human osteoblasts and to investigate whether aging affects treatment outcomes. Titanium disks with sandblasted and acid-etched (SLA) surfaces were treated with atmospheric pressure plasma (APP) and low-pressure plasma (LPP). For wetting behavior of the specimens after plasma treatment, the water contact angle was measured. The single-cell detachment force and amount of work of detachment of human osteoblasts were determined with single-cell force spectroscopy (SCFS). To evaluate the aging effect in APP-treated specimens, SCFS was conducted 10 and 60 min after treatment. Significantly higher hydrophilicity was observed in the APP and LPP treatment groups than in the control group, but no significant difference was observed between the APP and LPP groups. No significant difference in cell-detachment force or work of detachment was observed, and there were no significant differences according to the conditioning mechanisms and storage time. Conditioning of the titanium surfaces with APP or LPP was not a significant influencing factor in the initial adhesion of the osteoblasts. • A method for testing real "initial cell-attachment" of living osteoblasts is proposed. • Atmospheric pressure plasma and low-pressure plasma increase the hydrophilicity of the titanium surface in the same way. • Cell-detachment force and work of detachment in the conditioned specimens were not significantly different from untreated control specimen. [ABSTRACT FROM AUTHOR]

Objective The aim of this laboratory study was to evaluate the horizontal and vertical effects of the polymerization shrinkage of three-unit temporary fixed dental prostheses (FDPs) on the position of the prepared teeth. In addition, the reduction of these effects by using different fabrication techniques was evaluated. Methods A total of 192 temporary FDPs were fabricated using one methacrylate (MA) and two dimethacrylate (DMA) materials. Each material group (n = 64) was divided into two groups according to the fabrication methods (M1: curing on the prepared teeth, M2: curing in a silicone mold). Each fabrication group was divided into four subgroups (n = 8) according to the relining method used (B: no relining, S: spacer foil 300 μm, DG: grinding-out with 500 μm cutting depth, and FG: free grinding). The experimental apparatus consisted of two abutment teeth lowered at right angles into a silicone mold. One prepared tooth was embedded in silicone to simulate the periodontium and permit slight horizontal tooth movement. The dimensional changes were recorded with an optical microscope. The test images were superimposed and measured using image analysis software. Results The statistical analysis showed that there were significantly higher horizontal changes for the MA than the DMA resins in M1, while there was none in M2. Regarding the vertical changes, there were significant differences between the baseline group and all relining and fabrication groups in all materials. Significance Relining of directly fabricated temporary FDPs significantly reduces the effect of polymerization shrinkage and thus secures the position of the prepared teeth. [ABSTRACT FROM AUTHOR]

• Systematic meta-research analysis on endpoints in trials of palliative radiotherapy. • Trials are dominated by small sample sizes and external-beam radiotherapy. • "Patient-centered primary endpoints" are relatively often used in published trials. • Surrogate "tumor-centered primary endpoints" seem common in ongoing trials. Up to 50% of radiotherapy courses are delivered in palliative intent for various indications. Despite the large number of treated patients, we know little about the choice of endpoints in trials of palliative radiotherapy. Our primary aim was, therefore, to analyze primary endpoints in trials of palliative radiotherapy. We conducted a pre-registered (https://doi.org/10.17605/OSF.IO/GMCAF) meta-research analysis searching Pubmed/MEDLINE, EMBASE, CENTRAL, and " ClinicalTrials.gov " for clinical trials of palliative radiotherapy published 1990–2020. Endpoints were categorized in "patient-centered endpoints", including overall survival and patient-reported outcomes, and "tumor-centered endpoints" such as local control. The remainder were "other endpoints" including toxicity or observer-rated symptoms. We applied descriptive statistics to summarize data and logistic regression to assess if year of publication predicted the choice of primary endpoints. Of 7379 records screened, 292 were eligible. Trials were characterized by small sample sizes and use of external beam radiotherapy for metastases or thoracic primaries. Median patient age was 64 and median ECOG was 1. Only 64.4%(145/225) of published trials clearly stated their primary endpoint. Published trials employed a "patient-centered primary endpoint" in 45.5%(66/145) and a "tumor-centered primary endpoint" in 17.3%(25/145) of the cases. There was no statistically significant trend in time for the use of "patient-centered primary endpoints". Registered ongoing trials used a "patient-centered primary endpoint" in 32.8%(22/67) and a "tumor-centered primary endpoint" in 26.9%(18/67) of the cases. Although "patient-centered primary endpoints" appear relatively prevalent in published trials of palliative radiotherapy, their use is still suboptimal and appears to be lower in currently ongoing trials. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: The purpose of this in vitro study was to evaluate the bond strength and durability of adhesive bonding systems to amorphous and crystalline PEKK and fiber-reinforced PEEK using five types of surface conditioning methods. Methods: One hundred and fifty specimens of each material were conditioned mechanically and chemically, bonded with Multilink Automix to Plexiglas tubes, filled with Multicore Flow, and stored in water at 37°C for 3, 30 and 150 days. The long-term storage series were thermal cycled between 5 and 55°C for 10,000 times (30 days) or for 37,500 times (150 days) prior to tensile bond strength test (TBS). Statistical analysis was performed using Kruskal–Wallis and Wilcoxon tests with a Bonferroni–Holm correction for multiple testing (α =0.05). Results: Fiber-reinforced PEEK exhibited higher bond strengths in all five conditioning groups and at all three storage times than crystalline and amorphous PEKK, which showed lowest TBS. Highest TBS was achieved after conditioning with silica coating and priming (Rocatec Soft, Monobond Plus, Luxatemp Glaze & Bond; TBS up to 23.6MPa). Significance: The conditioning method has a significant influence to the bond strength of the bonding to the amorphous and crystalline PEKKs and fiber-reinforced PEEKs. [Copyright &y& Elsevier]

Abstract: Objectives: The aim of this study was to evaluate the linear and volumetric dimensional changes of six denture base resins processed by their corresponding injection-molding systems at 3 time intervals of water storage. Materials and methods: Two heat-curing (SR Ivocap Hi Impact and Lucitone 199) and four auto-curing (IvoBase Hybrid, IvoBase Hi Impact, PalaXpress, and Futura Gen) acrylic resins were used with their specific injection-molding technique to fabricate 6 specimens of each material. Linear and volumetric dimensional changes were determined by means of a digital caliper and an electronic hydrostatic balance, respectively, after water storage of 1, 30, or 90 days. Means and standard deviations of linear and volumetric dimensional changes were calculated in percentage (%). Statistical analysis was done using Student's and Welch's t tests with Bonferroni–Holm correction for multiple comparisons (α =0.05). Results: Statistically significant differences in linear dimensional changes between resins were demonstrated at all three time intervals of water immersion (p ≤0.05), with exception of the following comparisons which showed no significant difference: IvoBase Hi Impact/SR Ivocap Hi Impact and PalaXpress/Lucitone 199 after 1 day, Futura Gen/PalaXpress and PalaXpress/Lucitone 199 after 30 days, and IvoBase Hybrid/IvoBase Hi Impact after 90 days. Also, statistically significant differences in volumetric dimensional changes between resins were found at all three time intervals of water immersion (p ≤0.05), with exception of the comparison between PalaXpress and Futura Gen. Significance: Denture base resins (IvoBase Hybrid and IvoBase Hi Impact) processed by the new injection-molding system (IvoBase), revealed superior dimensional precision. [Copyright &y& Elsevier]