21 research outputs found

    Effectiveness of en masse versus two-step retraction:a systematic review and meta-analysis

    Get PDF
    Abstract Background This review aims to compare the effectiveness of en masse and two-step retraction methods during orthodontic space closure regarding anchorage preservation and anterior segment retraction and to assess their effect on the duration of treatment and root resorption. Methods An electronic search for potentially eligible randomized controlled trials and prospective controlled trials was performed in five electronic databases up to July 2017. The process of study selection, data extraction, and quality assessment was performed by two reviewers independently. A narrative review is presented in addition to a quantitative synthesis of the pooled results where possible. The Cochrane risk of bias tool and the Newcastle-Ottawa Scale were used for the methodological quality assessment of the included studies. Results Eight studies were included in the qualitative synthesis in this review. Four studies were included in the quantitative synthesis. En masse/miniscrew combination showed a statistically significant standard mean difference regarding anchorage preservation − 2.55 mm (95% CI − 2.99 to − 2.11) and the amount of upper incisor retraction − 0.38 mm (95% CI − 0.70 to − 0.06) when compared to a two-step/conventional anchorage combination. Qualitative synthesis suggested that en masse retraction requires less time than two-step retraction with no difference in the amount of root resorption. Conclusions Both en masse and two-step retraction methods are effective during the space closure phase. The en masse/miniscrew combination is superior to the two-step/conventional anchorage combination with regard to anchorage preservation and amount of retraction. Limited evidence suggests that anchorage reinforcement with a headgear produces similar results with both retraction methods. Limited evidence also suggests that en masse retraction may require less time and that no significant differences exist in the amount of root resorption between the two methods

    A new Triassic-Jurassic section in the southern part of the Holy Cross Mts. (Poland) implications for palaeogeography

    No full text
    Sedimentological, stratigraphical and geophysical studies across a new Triassic-Jurassic transition section in the Holy Cross Mts., Poland have revealed a large sedimentary hiatus embracing the entire latest Triassic–Early Jurassic – earliest Middle Jurassic time interval and yielded new data on the Triassic fluvial system and on Middle Jurassic shallow marine sedimentation. The presence of organic-walled dinoflagellate cysts allowed a precise age assignment of the black clay facies. Regional discussions and comparisons may be made with other areas with a similar depositional environment in Poland. For the first time a counterpart of the “Kościeliskie Beds” lithostratigraphic unit is proposed to exist in the Holy Cross Mts. area

    Treatment of Adults with Anterior Mandibular Teeth Crowding: Reliability of Little’s Irregularity Index

    No full text
    The attempt of this article was to assess reliability of Little’s Irregularity Index (LII) as for stability of the treatment outcomes in adults with crowded mandibular incisors. LII was measured on a digital cast prior to an orthodontic treatment (T1) of the 302 patients thus allowing us to establish the treatment plan, which called for (a) expansion (group 1), interproximal stripping (group 2), or extraction of one of the mandibular incisors. LII was measured after debonding (T2) and a year after retention (T3). Treatment resulted in significant reduction of LII values after treatment, in T1-T2 period in all groups. As for T2-T3 period it brought significant but clinically irrelevant relapse that occurred in groups 1 and 2; group 3 presented with insignificant improvement of occlusion. Conclusively, 30 years after introducing LII it has been a reliable parameter that allows selection of optimal treatment methods, provided that the appropriate ranges of values displaying dentoalveolar discrepancy are obeyed, namely, (1) up to 3 mm: expansion, (2) from 3 to 5 mm: interproximal enamel reduction, and (3) above 5 mm: extraction

    Patient specific outcomes of charged particle therapy for hepatocellular carcinoma : a systematic review and quantitative analysis

    No full text
    Hepatocellular carcinoma (HCC) is a raising condition world-wide. Most of patients are ineligible for surgery at diagnosis due to the advanced stage of the disease or poor medical condition of the patient. Charged particle therapy (CPT) is a radiotherapy modality showing promising results. The aim of this systematic review was to summarize current knowledge on patient-specific outcomes of CPT for HCC, including overall survival, local control, the effect of radiation dose and the toxicity burden. The systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). After comprehensive database search 17 cohorts (16 studies, 1516 patients) were included into qualitative and quantitative analyses; 11 of 16 studies were retrospective. Eleven studies were on protons, 2 studies were on protons and carbon ions and 4 on carbon ions alone, were identified. Median BED10 (biologically equivalent dose) range was 68.75\u2013122.5 GyE. Mean weighted overall survival across studies was 86%, 62%, 59% and 35% at 1, 2, 3 and 5 years, respectively. Mean weighted local control was 86%, 89%, 87% and 89% at 1, 2, 3 and 5 years, respectively. Adjusted morbidity rates were: 54% for acute G1-2 toxicities and 6% for acute 65G3 toxicities; 9% for late G1-2 toxicities and less than 4% for late 65G3 toxicities. There was no treatment-associated mortality. Conclusions: CPT offers high local control, acceptable overall survival and low post-treatment morbidity. Quality of findings, especially on toxicities, is decreased by incomplete reporting and retrospective designs of available studies. Therefore, there is a strong need for better reporting and prospective studies

    Sputtering and Implantation of VV-6025X Surface with Slow Heavy Ions Monitored with PIXE

    No full text
    In this work the characteristic radiation, emitted during interaction of medium energy (200 keV) ambient heavy ions (Ar) with Fe4Co66Si12B14Nb1Mo2Cu1Fe_{4}Co_{66}Si_{12}B_{14}Nb_{1}Mo_{2}Cu_{1} (VV-6025X) amorphous alloy, was measured in grazing incident-exit angle geometry and in time sequence, in order to determine dynamics of formation of subsurface region, damaged through implantation, sputtering and interface mixing. It was shown that structure and composition of surface is unstable against heavy ions irradiation due to preferential sputtering and implantation of ions, and recoils, and that the dynamics of such modification can be monitored in-situ with particle induced X-ray emission (PIXE) method
    corecore