Role of anatomical sites and correlated risk factors on the survival of orthodontic miniscrew implants:a systematic review and meta-analysis

Abstract Objectives The aim of this review was to systematically evaluate the failure rates of miniscrews related to their specific insertion site and explore the insertion site dependent risk factors contributing to their failure. Search methods An electronic search was conducted in the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Knowledge, Scopus, MEDLINE and PubMed up to October 2017. A comprehensive manual search was also performed. Eligibility criteria Randomised clinical trials and prospective non-randomised studies, reporting a minimum of 20 inserted miniscrews in a specific insertion site and reporting the miniscrews’ failure rate in that insertion site, were included. Data collection and analysis Study selection, data extraction and quality assessment were performed independently by two reviewers. Studies were sub-grouped according to the insertion site, and the failure rates for every individual insertion site were analysed using a random-effects model with corresponding 95% confidence interval. Sensitivity analyses were performed in order to test the robustness of the reported results. Results Overall, 61 studies were included in the quantitative synthesis. Palatal sites had failure rates of 1.3% (95% CI 0.3–6), 4.8% (95% CI 1.6–13.4) and 5.5% (95% CI 2.8–10.7) for the midpalatal, paramedian and parapalatal insertion sites, respectively. The failure rates for the maxillary buccal sites were 9.2% (95% CI 7.4–11.4), 9.7% (95% CI 5.1–17.6) and 16.4% (95% CI 4.9–42.5) for the interradicular miniscrews inserted between maxillary first molars and second premolars and between maxillary canines and lateral incisors, and those inserted in the zygomatic buttress respectively. The failure rates for the mandibular buccal insertion sites were 13.5% (95% CI 7.3–23.6) and 9.9% (95% CI 4.9–19.1) for the interradicular miniscrews inserted between mandibular first molars and second premolars and between mandibular canines and first premolars, respectively. The risk of failure increased when the miniscrews contacted the roots, with a risk ratio of 8.7 (95% CI 5.1–14.7). Conclusions Orthodontic miniscrew implants provide acceptable success rates that vary among the explored insertion sites. Very low to low quality of evidence suggests that miniscrews inserted in midpalatal locations have a failure rate of 1.3% and those inserted in the zygomatic buttress have a failure rate of 16.4%. Moderate quality of evidence indicates that root contact significantly contributes to the failure of interradicular miniscrews placed between the first molars and second premolars. Results should be interpreted with caution due to methodological drawbacks in some of the included studies

Investigation of Surface Nanostructuring, Mechanical Performance and Deformation Mechanisms of AISI 316L Stainless Steel Treated by Surface Mechanical Impact Treatment

Nanostructured materials exhibit superior properties with respect to their bulk counterpart. Recently, a new processing method for surface nanostructuring of metallic materials called surface mechanical impact treatment (SMIT) was developed. In this study, the surface microstructural features due to the refinement process of AISI 316L stainless steel by means of SMIT and subsequent mechanical performance were investigated. The effects of SMIT processing parameters, i.e. ball size and treatment duration, were studied in terms of microstructural evolutions using X-ray diffraction, transmission electron microscopy, optical microscopy, and field emission scanning electron microscopy analyses, and mechanical properties through hardness and tensile tests. A gradient nanostructured surface layer was successfully formed on the surface of the treated samples. The mean grain size was measured to be similar to 20 nm in the topmost surface layer and increased with increasing depth. Microstructural examinations showed that the twins and their intersections (rhombic blocks) formed in the surface layers. It was found that the mechanical performance of the treated samples is effectively enhanced. The surface hardness of the treated samples increased about 3 times while the yield strength of the samples increased with increasing SMIT time and size of the ball up to 2.5 times. The grain refinement mechanisms, mechanical properties, and fracture behavior were subsequently analyzed and discussed

Exploring the cancer-testis antigen BORIS to design a novel multi-epitope vaccine against breast cancer based on immunoinformatics approaches

Recently, cancer immunotherapy has gained lots of attention to replace the current chemoradiation approaches and multi-epitope cancer vaccines are manifesting as the next generation of cancer immunotherapy. Therefore, in this study, we used multiple immunoinformatics approaches along with other computational approaches to design a novel multi-epitope vaccine against breast cancer. The most immunogenic regions of the BORIS cancer-testis antigen were selected according to the binding affinity to MHC-I and II molecules as well as containing multiple cytotoxic T lymphocyte (CTL) epitopes by multiple immunoinformatics servers. The selected regions were linked together by GPGPG linker. Also, a T helper epitope (PADRE) and the TLR-4/MD-2 agonist (L7/L12 ribosomal protein from mycobacterium) were incorporated by A(EAAAK)3A linker to form the final vaccine construct. Then, its physicochemical properties, cleavage sites, TAP transport efficiency, B cell epitopes, IFN-γ inducing epitopes and population coverage were predicted. The final vaccine construct was reverse translated, codon-optimized and inserted into pcDNA3.1 to form the DNA vaccine. The final vaccine construct was a stable, immunogenic and non-allergenic protein that contained numerous CTL epitopes, IFN-γ inducing epitopes and several linear and conformational B cell epitopes. Also, the final vaccine construct formed stable and significant interactions with TLR-4/MD-2 complex according to molecular docking and dynamics simulations. Moreover, its world population coverage for HLA-I and HLA-II were about 93 and 96, respectively. Taking together, these preliminary results can be used as an appropriate platform for further experimental investigations. Communicated by Ramaswamy H. Sarma. © 2021 Informa UK Limited, trading as Taylor & Francis Group

Tooth-borne versus bone-borne rapid maxillary expansion for transverse maxillary deficiency: A systematic review

Purpose: The aim of this study was to compare dentoskeletal effects of bone-borne expanders with those of conventional expanders in adolescent and adults having transverse maxillary deficiency. Methods: All randomized clinical trials (RCTs) comparing the effects of bone-borne with those of tooth-borne expansion for treatment of maxillary transverse deficiency in adults and adolescents with maxillary transverse deficiency or posterior crossbite were included. The systematic search was irrespective of language and publication type. The electronic search was conducted from 1980 to January 2018. Results: The electronic searches retrieved 713 references after screening for eligibility criteria. Eight studies met the inclusion criteria for this systematic review involving 289 participants. Four studies compared rapid maxillary expansion (RME) between bone-borne and tooth-borne devices and indicated effectiveness of both devices on maxillary expansion. In the first molar region, there was no significant difference between two devices in either skeletal or dental expansion. Two studies compared the effects of bone-borne and tooth-borne device following SARME and suggested no significant difference regarding amount and pattern of expansion at various levels and in molar and premolar region between two groups. Two studies compared bone-borne and tooth-bone-borne devices. Conclusion: Within the limit of the present evidence regarding maxillary expansion, it seems that both tooth-borne and bone-borne devices result in the same outcome in terms of the amount of maxillary expansion, dental tipping, stability and perceived pain both in RME and SARME procedure. PROSPERO registration: CRD42017061078

Potential anticancer effects of cell wall protein fractions from Lactobacillus paracasei on human intestinal Caco-2 cell line

Abstract: Consumption of probiotics has an important role in colorectal cancer prevention. In this study, we aimed to explore that the cell wall protein fractions from Lactobacillus paracasei could induce apoptosis on Caco-2 cell line. The cell wall proteins from L. paracasei were fractionated by gel filtration chromatography (F1, F2 and F3) and characterized by polyacrylamide gel electrophoresis (SDS-PAGE). The anticancer properties were evaluated using MTT assay and Annexin V-FITC/PI staining. Administration of L. paracasei increased a significant concentration- and time-dependent anti-proliferative effect on Caco-2 cell line, determined by cell viability assays. However, a dramatic decrease in cell viability of Caco-2 cells was observed at the concentration of 100 µg ml−1 of F1 L. paracasei for 72 h (58% cell viability, P < 0·05) The results showed that F1 L. paracasei could induce apoptosis in Caco-2 cancer cell line by increased in annexin V and propidium iodide staining for 72 h (up to 90·6%, P < 0·001). These results indicated the importance of the anticancer effects of cell wall protein fractions of L. paracasei in human colon carcinoma Caco-2 cell line. Thus, cell wall protein fractions of L. paracasei can be a potential chemotherapeutic agent against Caco-2 cell lines. Significance and Impact of the Study: Significance and Impact of the Study: Our findings revealed that the newly identified cell wall protein fractions from probiotic Lactobacillus paracasei inhibit the cell growth of human colon carcinoma cell line (Caco-2), and the results indicated that the cell wall proteins from L. paracasei can be a potential chemotherapeutic agent against Caco-2 cell line