Shear bond strength of orthodontic color-change adhesives with different light-curing times

BACKGROUND: The purpose of this study was to evaluate the effect of light-curing time on the shear bond strength (SBS) of two orthodontic color-change adhesives (CCAs). MATERIALS AND METHODS: A total of 72 extracted premolars were randomly assigned into 6 groups of 12 teeth each. Subsequent to primer application, a metal bracket was bonded to the buccal surface using an orthodontic adhesive. Two CCAs (Greengloo and Transbond Plus) were tested and one conventional light-cured adhesive (Resilience) served as control. For each adhesive, the specimens were light-cured for two different times of 20 and 40 s. All the specimens underwent mechanical testing using a universal testing machine to measure the SBS. Adhesive remnant index (ARI) was used to assess the remnant adhesive material on the tooth surface. All statistical analyses were performed using SPSS software. The significance level for all statistical tests was set at P ≤ 0.05. RESULTS: The SBSs of the tested groups were in the range of 14.05-31.25 MPa. Greengloo adhesive showed the highest SBS values when light-cured for 40 s, and Transbond Plus adhesive showed the lowest values when light-cured for 20 s. ARI scores of Transbond Plus adhesive were significantly higher than those of controls, while other differences in ARI values were not significant. CONCLUSION: Within the limitations of his study, decreasing the light-curing time from 40 to 20 s decreased the SBS of the tested adhesives; however, this decline in SBS was statistically significant only in Transbond Plus adhesive

Islamic fasting and oral health and diseases

Fasting is a religious obligation, which can be challenging for individuals with oral conditions due to its stringent code of conduct. Moreover, food abstinence during fasting can restrict oral feeding even further in patients whose nutrition has been already compromised. Previous research has mainly concentrated on oral hygiene and gum health, disregarding orodental conditions and diseases. This highlights the importance of further research in this regard. In this paper, we intended to clarify the correlation between fasting and oral injections, bleeding following tooth extraction, and brushing to overcome common misconceptions which indicate the breach of religious disciplines under such circumstances. We also aimed to determine the grave effects of fasting on health in case of severe immunological deficiencies, chronic oral ulcers and certain drug administration protocols for those with rigid religious beliefs

A meta-analysis and meta-regression of association between MTHFR A1298C polymorphism and nonsyndromic cleft lip/palate risk: An evaluation based on five genetic models

Objective: The present meta-analysis is intended to assess the association between NSCL/P risk and methylenetetrahydrofolate reductase (MTHFR) A1298C polymorphism in case-control studies. Materials and methods: The Web of Science, PubMed/Medline, Scopus, and Cochrane Library databases were searched for related articles published by April 2019. Review Manager 5.3 was applied to measure the odds ratios (ORs) with 95 confidence interval (CI) in the analyses assessing the strength of the association between A1298C polymorphism and NSCL/P risk. Results Sixteen studies were involved and analysed in this meta-analysis. Altogether, the reviewed articles included 2677 NSCL/P patients and 3669 controls. The pooled ORs of the allele, homozygote, heterozygote, dominant, and recessive models were 1.11 (95 CI: 0.94, 1.30; P = 0.21), 1.14 (95 CI: 0.94, 1.37; P = 0.18), 0.98 (95 CI: 0.80, 1.20; P = 0.87), 1.03 (95 CI: 0.86, 1.22; P = 0.79), and 1.18 (95 CI: 0.99, 1.41; P = 0.07), respectively. The analysis did not identify any significant association between the polymorphism and the risk of NSCL/P in any ethnicity or source of controls. Conclusions: This meta-analysis revealed that A1298C polymorphism is not associated with NSCL/P susceptibility, and the subgroup analyses based on ethnicity and the source of cases further confirmed this result. © 2020 CE

Multi-camera multiple vehicle tracking in urban intersections based on multilayer graphs

© The Institution of Engineering and Technology 2020 Vehicle visual tracking is a challenging issue in intelligent transportation systems. The tracking gets more challenging when vehicles change direction at intersections. Undetermined motion flows, occlusion, and congestion are the potential issues of vehicle tracking at intersections. In this study, a new method for tracking multiple vehicles from a multi-view is proposed to overcome occlusion caused at the intersections with undetermined motion flows. In the authors\u27 method, a multilayer graph is presented that assigns motion flows to distinct layers with different neighbourhoods for each layer represented by the graph\u27s edges. Hence, the vehicle trajectories are distributed among layers such that vehicles entering from the same side with similar motion flows are assigned to the same layer. All multilayer graphs of different views are mapped to the graph of the selected view. Then, tracking is performed on the distinct layers of the mapped multilayer graph by computing min-cost flows. In cases such as vehicle crossing, misdetection, or occlusion, the method can predict the vehicle\u27s tracks by using history, layer neighbourhoods, and other views\u27 information. Experimental results show a consistency of the ground truth and the analysis obtained using the proposed method in tracking vehicles in the inner part of the intersection