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In orthodontic treatment, mechanotherapy is needed to move the teeth. It is a challenge for the dentist to maximize the desired tooth movement without losing anchorage. Some experts have proposed a mechanical device to prevent the loss of anchorage, but it is still common to lose anchorage and cause side effects such as root resorption, white spots, caries, gingivitis and others. The use of bisphosphonates is recommended for the control of relapse and even for establishing pharmacological anchors. Bisphosphonates are pharmacological agents used to treat osteoporosis patients. This pharmacological agent is a potential bone resorption inhibitor. So, the use of bisphosphonates can be useful for orthodontist to control anchorage movement. Many literatures have begun to discuss the use of BP in orthodontic treatment patients. This review article aims to analyze the literature that discusses the influence of BP on orthodontic tooth movement.

Mohamed Nedali is a contemporary Moroccan writer of French expression born in 1962 in Tahannaout, about thirty kilometers from Marrakech where he still lives. Having written eight novels with a realist vocation, he makes his region his favorite place and fiction because, as he says in an interview, “in literature one only speaks very well of a place one knows so well”. However, this attachment to space, or at least this rootedness in identity that demonstrate the territorial anchoring of the author, seems insufficient to serve his realistic vision. It is nevertheless true that the intrusion of vernacular languages in a text written in a foreign language is not without importance because it constitutes a significant element in a realistic fresco. Indeed, the text of Nedali is strewn with Moroccan expressions. This intrusion is not gratuitous and illustrates the role that the contact of languages can have in a fictional narrative. Moreover, the choice of anthroponyms in Nedali’s fiction is not arbitrary, as it is thoughtful and serves the author’s vision. Being a writer of soil and a good connoisseur of the Moroccan society, the author uses it to create a fresco whose contrasts illustrate his bias and his refusal of social evils.

Актуальность. В настоящее время более 75 % проводимых подземных горных выработок поддерживаются при помощи анкерного крепления. В процессе длительной эксплуатации выработок возникают деформации приконтурного массива пород и элементов крепи. Актуальной научно-практической задачей представляется выявление типовых форм деформаций пород и элементов крепи с целью разработки проектных решений и обоснования параметров крепи при производстве текущего ремонта или восстановления подземных выработок. Цель: разработка проектных решений и обоснование параметров анкерного крепления при ремонте и восстановлении подземных горных выработок. Методы: натурные исследования, статистическая обработка результатов экспериментальных исследований. Результаты. Приведено описание, причины возникновения и формы проявления геомеханических процессов в приконтурном углепородном массиве горных выработок, закрепленных анкерной крепью. На основе длительных натурных наблюдений установлено шесть форм типовых деформаций приконтурного массива. Процесс сводообразования в кровле выработок начинается с разуплотнения приконутрного слоя, которое служит причиной расслоения пород под действием гравитационных сил, а также образования полостей. Отжим угля из боков выработок и вывалы угля происходят в связи с образованием вокруг выработки зон неупругих деформаций, где уголь и породы находятся в несвязанном состоянии и удерживаются в равновесии за счёт сил трения и отпора крепи. Ширина зоны неупругих деформаций зависит от многих факторов. Существенное влияние оказывают ширина выработки и угол внутреннего трения. При увеличении ширины выработки увеличивается коэффициент концентрации напряжений в боках. Разработаны проектные решения по усилению крепления или полной перекрепке поврежденных участков горных выработок при геомеханических процессах локального вывалообразования. Они включают в себя: схему установки, обоснование параметров и номенклатуру применяемых элементов крепи-усиления, технологию работ, список применяемого оборудования. Relevance. More than 75 % of underground mine workings are supported by anchorage nowadays. In the case of long-term mine workings maintenance the deformations of surrounding rock massif and anchoring elements occur. The surrounding rock massif typical forms deformations determination in order to develop the design solutions and substantiate anchorage parameters is currently urgent scientific and practical task. Especially it is important in case of mine workings support repair or recovery stages. The main aim is mine working anchorage design solutions and parameters substantiate during the repair and recovery stages. Methods: field measurements, statistical processing of results. Results. The paper introduces the description, causes of occurrence and manifestation forms of geomechanical processes in surrounding rock massif supported by anchorage. Based on the long-term field measurements six forms of rock massif typical deformations have been established. The roof bridging begins with decompaction of rocks, which causes rocks stratification under the influence of gravity. This results in cavities formation and lower layers separation from upper ones. Because of formation of the plastic deformation zone around mine workings the extraction and dumping coal from walls occur. Coal and rocks are in an unbound state and are kept in balance due to the forces of friction and resistance of the support in the zones of plastic deformations. Its width depends on many factors such as the working width and the internal friction angle. The coefficient of stress concentration in the walls rises up due to growth of mine working widht.

The strength assessment of existing reinforced concrete structures is challenging where deterioration and detailing deficiencies are present. The anchorage of the internal steel reinforcement can be critical under particular confinement conditions of external pressure, concrete cover and transverse reinforcement. The interaction between different confinement contributions and their effects on bond were investigated with a novel experimental set-up that removed the parasitic support pressure. With significant transverse reinforcement and varying concrete cover, maximum bond strengths were obtained for intermediate cover-to-diameter ratios. The transverse reinforcement contribution depended on the occurrence of splitting cracks. These findings can lead to improved assessment and maintenance strategies.

Short stems in total hip arthroplasty (THA) are becoming increasingly popular. In Germany, already 10.4% of all primary THAs are performed using a cementless short stem. The concept of modern, calcar-guided, short stems aims for an individualized reconstruction of the hip anatomy by following the calcar of the femoral neck, a bone- and soft-tissue-sparing implantation technique, and physiological loading. The stem design uses either metaphyseal fixation alone or additional diaphyseal anchoring, depending on the stem alignment and indication. These individualized anchorage types increase the potential indications for the safe use of a short stem. The design features may account for potential advantages of current short stem implants compared with earlier short-stem designs, particularly in cases of reduced bone quality or osteonecrosis of the femoral head and femoral neck fractures. The implantation technique, however, requires distinct knowledge regarding the characteristics of varus and valgus positioning, with the potential for clinical consequences. A learning curve for surgeons new to this technique must be taken into account. Cortical contact with the distal lateral cortex appears to be crucial to provide sufficient primary stability, and the use of intraoperative imaging to identify “undersizing” is highly recommended. Current results of several national registries indicate that calcar-guided short stems are among the most successful implants in terms of mid-term survivorship. However, long-term data remain scarce. This review introduces the characteristics of calcar-guided short-stem THA and summarizes the current evidence.

Experimental testing of deformed rebar anchors (DRAs) has not been performed extensively, so there is limited test data to understand their failure behavior. This study aims to expand upon these limited tests and understand the behavior of these anchors, when loaded in tension. Analytical benchmark models were created using available test data and a parametric study of deformed rebar anchors was performed. Anchor diameter, spacing, embedment, and number of anchors were varied for a total of 49 concrete breakout simulations. The different failure modes of anchors were predicted analytically, which showed that concrete breakout failure is prominent in the DRA groups. The predicted concrete breakout values were consistent with mean and 5% fractile concrete capacities determined from the ACI concrete capacity design (CCD) method. The 5% fractile factor determined empirically from the simulation results was kc = 26. This value corresponds closely with kc = 24 specified in ACI 318-19 and ACI 349-13 for cast-in place anchors. The analysis results show that the ACI CCD formula can be conservatively used to design DRAs loaded in tension by applying a kc factor no greater than 26.

The prevalence and treatment need for bimaxillary proclination is significant, especially among patients with Chinese or African-Carribean descent. Treatment commonly constitutes extraction of upper and lower first permanent premolars with maximum anchorage requirement. Various anchorage devices exist. However, a systematic review or meta-analysis of soft tissue changes in treatment of bimaxillary proclination is scarce; one comparing the effects of different anchorage protocol to the soft tissue structure in treating bimaxillary proclination patients has not been done yet. Treatment of bimaxillary proclination, may seem to apply similar mechanics with other treatment requiring labial retroclination, but differs in treatment aims, outcome and stability of the overlying soft tissue 4. Due to the highly aesthetics-driven nature of treatment, optimal and predictable post treatment facial harmony and aesthetics are paramount. Thus, an evidence-based approach to anchorage protocol with optimal facial aesthetics will be an important asset in treatment planning of bimaxillary proclination cases. Through this study, we aim to conduct a systematic review comparing anchorage protocols and soft tissue changes in treating bimaxillary proclination patients for that reason.

Objective The aim of this systematic review was to evaluate the complications and side effects associated with the clinical use of orthodontic miniscrews by systematically reviewing the best available evidence. Methods A survey of articles published up to March 2020 investigating the complications associated with miniscrew insertion, in both the maxilla and mandible, was performed using 7 electronic databases. Clinical studies, case reports, and case series reporting complications associated with the use of orthodontic miniscrew implants were included. Two authors independently performed study selection, data extraction, and risk-of-bias assessment. Results The database survey yielded 24 articles. The risk-of-bias assessment revealed low methodological quality for the included studies. The most frequent adverse event reported was root injury with an associated periradicular lesion, vitality loss, pink discoloration of the tooth, and transitory loss of pulp sensitivity. Chronic inflammation of the soft tissue surrounding the miniscrew with mucosal overgrowth was also reported. The other adverse events reported were lesion of the buccal mucosa at the insertion site, soft-tissue necrosis, and perforation of the floor of the nasal cavity and maxillary sinus. Adverse events were also reported after miniscrew removal and included secondary bleeding, miniscrew fracture, scars, and exostosis. Conclusions These findings highlight the need for clinicians to preliminarily assess generic and specific insertion site complications and side effects.

This paper presents an investigation into the bond strength of three common façade stones, namely, travertine, granite, and marble, to a concrete substrate using a shear-splitting test. The effects of anchorage, the number of curing days, and the presence of an anti-freezing agent in cement–sand mortar on bond strength were studied. The results show that the number of curing days had a significant impact on the bond strength between the stones and the substrates. The presence of an anti-freezing agent and accelerator increased bonding during the initial days, but this effect gradually decreased. The use of anchorage had a positive effect on the bond strength, particularly with fewer curing days. Granite had the lowest bond strength when no anchorage was used due to its low permeability. Based on the findings, a novel fuzzy logic approach was proposed to predict the bond strength. This study provides valuable insights into improving the bonding of façade stones to substrates and can aid in the safe and efficient use of these materials in construction.

Objective To evaluate the mandibular buccal shelf (MBS) in terms of the angulation and bone depth and thickness according to sex, age, and sagittal and vertical skeletal patterns in a Colombian population using cone-beam computed tomography (CBCT). Accordingly, the optimal site for miniscrew insertion in this area was determined. Methods This descriptive, retrospective study included 64 hemi-arches of 34 patients. On CBCT images, the angulation, buccal bone depth (4 and 6 mm from the cementoenamel junction [CEJ] of MBS), and buccal bone thickness (6 and 11 mm from the CEJ of MBS) were measured at the mesial and distal roots of the mandibular first and second molars. Results There were no statistically significant differences in the angulation, depth, and thickness of MBS between male and female patients. The values for the bone around the distal root of the mandibular second molar were significantly greater than the other values. The osseous characteristics were significantly better in participants aged 16–24 years. Class III patients exhibited the best osseous characteristics, with the bone depth at 6 mm being significantly different from that in Class I and Class II patients. Although values tended to be greater in patients with low angles, the difference was not statistically significant. Conclusions MBS provides an optimal bone surface for miniscrew insertion, with better osseous characteristics at the distal root of the mandibular second molar, 4 mm from CEJ. Adolescent patients, Class III patients, and patients with a low angle exhibit the most favorable osseous characteristics in the MBS area.

Summary Background Class III patients are characterized by a deficiency of the maxilla and/or a prognathism of the mandible and require early treatment. Diagnosis This case report describes the treatment of a 5-year-old patient with a skeletal class III relationship, a significant mandibular symphysis deviation towards the right side and a different height of the mandibular angles. Management and outcome The patient was treated with rapid maxillary expander combined with miniscrew, facemask and aligners. A functional and aesthetic occlusion in an improved facial profile was established at the end of the orthodontic treatment. Pre-treatment, post-treatment and one year retention records for the patient are presented. Discussion Class III patients require early treatment in order to optimize the traditional expander effects; subsequently hybrid anchorage allowed to maximize skeletal advancement. In addition, loss of space for the erupting teeth and dento-alveolar tipping were avoided. The good results of the phase I treatment and of the active retainer meant that a complex case would become relatively simple at the phase II treatment.

The article aims to identify constitutive elements of a dibian ecopoetry based on the two Algerian and Nordic trilogies. It starts fromthe depiction of the land and, in particular, of the author's city of origin, which appears as a unit culturally marked by diversity. This article identifies the poetic transposition of this depiction, as an entity bindingunity and diversity. Its first objective is to define what characterises the place of origin, and the way in which, poetically, the conditions of a habitat, understood as oikos, shelter, refuge, and as an appropriated share of space, are poetically outlined. It then considers man's position in this permeable space both in it and from it, and the crossing from the inside to the outside and vice-versa. He shows how the Dibian protagonist, observer and watchman, can "open up to the world", so to speak, and become an adventurer and an explorer when he responds to the command of the "outside". El artículo trata de extraer elementos constitutivos de una ecopoética en Mohammed Dib apoyándose en las dos trilogías, argelina y nórdica. Partiendo de la representación de la tierra y, en particular, de la ciudad de origen del autor, identifica la transposición poética de esta representación como entidad que une unidad y diversidad. Su primer objetivo es así definir lo que caracteriza el lugar de anclaje, y cómo, poéticamente, se dibujan las condiciones de un hábitat, entendido como oikos, refugio, parte apropiada del espacio. Luego se interesa por la posición del hombre en este lugar y desde este lugar, y por la porosidad y el paso de dentro hacia fuera y viceversa. Muestra cómo el protagonista en Dib, observador y centinela, puede abrirse al mundo y convertirse en aventurero y explorador cuando responde a la orden del exterior. L’article tend à dégager des éléments constitutifs d’une écopoétique dibienne en s’appuyant sur les deux trilogies, algérienne et nordique. Partant de la représentation de la terre et, notamment, de la ville d’origine de l’auteur, il identifie la transposition poétique de cette représentation comme entité joignant unité et diversité. Son premier objectif est ainsi de définir ce qui caractérise le lieu d’ancrage, et la façon dont, poétiquement, se dessinent les conditions d’un habitat, entendu comme oikos, abri, refuge, part appropriée d’espace. Il s’intéresse ensuite à la position de l’homme en ce lieu et à partir de ce lieu, et à la porosité et au passage du dedans vers le dehors et vice-versa. Il montre comment le protagoniste dibien, observateur et guetteur, peut s’ouvrir au monde et devenir aventurier et explorateur quand il répond à l’injonction du dehors.

Among different details in old riveted railway bridges throughout the world, connections such as stringer-to-floor-beam double-angle connections are one of the most fatigue-prone details. These connections are subjected to fatigue loadings due to the secondary out-of-plane deformation. However, there are only few traditional strengthening techniques that are proved to be not so effective in permanently addressing the fatigue issue. In this study, a novel un-bonded prestressed retrofitting solution is proposed for strengthening riveted/bolted steel angle connections. The strengthening system consists of prestressed carbon fiber reinforced polymer (CFRP) rods, which are clamped at the ends using mechanical wedge-barrel anchors. The prestressing force of CFRP rods are transmitted to the strengthened member using the clamps functioning purely by friction. Therefore, an adhesive bonding is not required, and, no damage is imposed to the parent structure. The installation procedure consists of two main stages: presetting the wedges into the barrels, and, prestressing the CFRP rods. For the presetting, a novel method is introduced, making it possible to apply high presetting forces on-site. The application of prestressing force is done by pumping the hydraulic jacks. The static behavior of the strengthening system is experimentally investigated through pull-off tests. In addition, the fatigue behavior of the strengthening system is studied by the laboratory tests on stringer-to-floor-beam double-angle connections. Furthermore, stress distribution in the clamping system and connected parts was analyzed using a Finite Element (FE) model leading to final design of the system.

Background The aim of the current study was to comparatively assess the primary stability of different Straumann® implant designs (BLX, Straumann Tapered Effect, Bone Level Tapered, and Standard Plus) via resonance frequency analysis by using an implant insertion model in freshly slaughtered bovine ribs with and without cortical bone. Tapered Effect (4.1 × 10 mm), Bone Level Tapered (4.1 × 10 mm), Standard Plus (4.1 × 10 mm), and BLX (4.0 × 10 mm) implants were inserted into the distal epiphysis on the longitudinal axis of the freshly slaughtered bovine ribs. As a control, implants with the same sizes were inserted into the proximal diaphysis. The stability of the implants was examined with resonance frequency analysis. Results BLX and Tapered Effect implants showed higher implant stability quotient values in both study and control groups. All implant systems showed a significant decrease of mechanical anchorage in the study group. BLX and Bone Level Tapered designs had a significantly lower loss of mechanical anchorage in the lack of cortical bone. Conclusion Both Tapered Effect and BLX designs could ensure sufficient initial stability; however, BLX implants could be an appropriate option in the lack of cortical bone and poor bone quality at the implant recipient site. Clinical relevance BLX is a novel implant system, which could be especially beneficial in the presence of spongious bone type at posterior maxillae.

This paper presents some of the initial results from an ongoing research project which concerns a new NSMR strengthening method, expected to provide high ductility and strengthening effect as well as increased response consistency. A prestress of 1100 MPa activation was applied to the ductile NSMR system and compared to a reference beam. Ductility in this system is provided by a response controlling anchorage system, which interacts with the adhesively bonded NSMR. The proposed adhesive has a low E-modulus which is expected to reduce stress concentration issues of adhesively bonded joints when compared to stiffer epoxy adhesives are used, where IC-debonding seems to be the dominating failure mode. A beam deflection increase of approximately 105% has been observed when using the low E-modulus adhesive compared to the the epoxy adhesive. Change in the failure modes were furthermore observed, where the brittle de-bonding failure modes were mitigated thus extending the yielding regime with approximately 150%.

Background The aim of the study was to evaluate the efficacy of a novel en masse distalization method in the maxillary arch in combination with a completely customized lingual appliance (CCLA; WIN, DW Lingual Systems, Germany). Therefore, we tested the null-hypothesis of a significant deviation from an Angle-Class I canine relationship and a normal overjet defined by an individual target set-up after dentoalveolar compensation in Angle Class II subjects. Methods This retrospective study included 23 patients, (m/f 3/20, mean age 29.6 years (min/max, 13.6/50.9 years)), with inclusion criteria of an Angle Class II occlusion of more than half a cusp prior to en masse distalization and treatment completed consecutively with a CCLA in combination with a mini-screw (MS) anchorage for uni- or bilateral maxillary distalization (12 bilateral situations, totalling 35). Plaster casts taken prior to (T0) and following CCLA treatment (T3) were compared with the treatment plan / set-up (TxP, with a Class I canine relationship and a normal overjet as the treatment objective). MSs were placed following levelling and aligning (T1) and removed at the end of en masse distalization at T2. Statistical analysis was carried out using Schuirmann’s TOST [two one-sided tests] equivalence test, based on a one-sample t-test with α = 0.025 on each side (total α = 0.05). Results Ninety-seven percent of planned correction of the canine relationship was achieved (mean 3.6 of 3.7 mm) and also 97 % of the planned overjet correction (mean 3.1 of 3.2 mm), with a statistically significant equivalence (p n = 2 of 35 mini-screws. However, in each instance, the treatment was completed, as scheduled, without replacing them. Accordingly, the null-hypothesis was rejected. Conclusions The technique presented allows for a predictable correction of an Angle-Class II malocclusion via dentoalveolar compensation with maxillary en masse distalization.

Anchorage of shear reinforcement, such as links or stirrups, can be performed by providing hooks, bends or heads at their ends, by welding transverse reinforcement or by closing open stirrups with pins. Hooks and bends, also used to enhance the anchorage of flexural reinforcement at the end regions of beams and slabs, have often been preferred because of their simple and cost-effective production. Such anchorages present nevertheless several peculiarities that shall be accounted for. They are relatively sensitive to their detailing (mandrel diameter, length of the tail segment between bar end and bent region) as well as to the cracking state of the surrounding concrete. Also, brittle failures can occur due to spalling of the concrete cover in case of bars near to a free surface. The anchorage with hooks and bends is currently still widely designed according to old detailing rules, based on the results of tests performed in many cases with materials whose properties are significantly different than those of nowadays. Also, no mechanical models are available for a consistent verification and detailing, acknowledging the different potential failure modes and their interaction with the surrounding concrete. In an effort to provide a consistent approach to its design and verification, this paper presents an investigation addressed at understanding the mechanical response and performance of bend and hook anchorages. To that aim, the results of an experimental programme performed with state-of-the-art instrumentation are introduced. By means of analysis of Digital Image Correlation and Fibre-Optic Measurements, the complete transfer of forces is analysed under different circumstances. On that basis, a consistent mechanical model is developed and validated, also reproducing a large variety of tests found in the literature. The paper introduces eventually several practical considerations on the activation of shear reinforcement in beams, and the level of performance required at its anchorages.

Orientador: Luiz Carlos de Almeida Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo Resumo: Esta pesquisa pretende contribuir, através de análises numéricas paramétricas, para a compreensão do comportamento de blocos de concreto armado sobre duas estacas, submetidos a carregamentos verticais. Para o estudo paramétrico foram realizadas alterações nos comprimentos das armaduras de ancoragem dos pilares, com o objetivo de verificar a influência desta variável nos blocos após as modificações. A análise numérica é não linear e com o emprego dos elementos finitos bidimensionais do programa computacional ATENA 2D, considerando aderência perfeita entre aço e concreto. Os modelos simulados foram baseados em nove modelos de referência oriundos da pesquisa de Munhoz (2014) e, com o intuito de validar qualitativamente as simulações, realizaram-se comparações entre os resultados experimentais e numéricos. Os modelos de referência são blocos rígidos sobre duas estacas, sob pilares com taxas de armadura variando em 1,0%, 2,5% e 4,0%. A partir dos modelos validados, variaram-se os comprimentos das armaduras de ancoragem em 34,0 cm, 20,0 cm, 10,0 cm e 3,0 cm, totalizando trinta e seis modelos numéricos. Com os resultados obtidos foram investigados os comportamentos dos blocos, relativos às curvas carga versus deslocamento, às cargas de ruptura, às deformações e tensões nas armaduras, aos fluxos de tensões, aos panoramas de fissuração e aos modos de ruptura. As comparações realizadas entre modelos experimentais e numéricos apresentaram concordância nos resultados obtidos e, como esperado, constatou-se que os modelos numéricos apresentaram maior rigidez estrutural. No âmbito do estudo paramétrico, as simulações dos blocos apresentaram comportamentos semelhantes, ou seja, o comprimento das armaduras de ancoragem dos pilares não é um fator preponderante para os mecanismos de funcionamento interno desses elementos Abstract: This research intends to contribute, through parametric numerical analysis, to understanding the behavior of concrete two pile caps, under vertical loads. Changes were made in column¿s anchorage reinforcements lengths for the parametric study, in order to verify the influence of this variable on the pile caps after the modifications. The numerical analysis is non-linear applying bidimensional finit elements with ATENA 2D package, perfectly adherent is considered between steel and concrete. The simulated models were based on nine reference models from Munhoz (2014) research and, in order to qualitatively validate the simulations, comparisons between experimental and numerical results were made. The reference models are rigid pile caps, under columns with reinforcement rate varying in 1,0%, 2,5% e 4,0%. From the validated models, anchorage reinforcement were varied in 34,0 cm, 20,0 cm, 10,0 cm e 3,0 cm, totaling thirty six numerical models. With the results, pile caps behaviors, related to the load versus displacement curves, the ultimate loads, the deformations and stresses in reinforcements, the stress flows, the crack panorams and the rupture modes were investigated. Experimental and numerical models comparison results obtained showed agreement and, as expected, it was verified that the numerical models presented greater structural stiffness. For parametrical study, the pile caps simulations presented similar behavior, in other words, columns anchorage reinforcements lengths is not a preponderant factor for the internal mechanisms operation of these elements Mestrado Estruturas Mestre em Engenharia Civil CAPES 01P-04376/2015

Reinforced concrete structures are subjected to several sources of deterioration that can cause a progressive reduction in performance. Among the existing infrastructure typologies, reinforced concrete half-joint bridges are particularly critical. This common structural configuration is characterised by a reduction in depth at the supports. The underside of the full-depth section does not benefit from support confinement in the anchorage zone of the longitudinal tensile reinforcement. Moreover, leakage of contaminated water often causes corrosion of the internal steel reinforcement and cracking of the concrete cover. Thus, half-joints are particularly vulnerable to bond degradation due to corrosion and cracking. To develop an improved understanding of deterioration in reinforced concrete, and half-joints in particular, three experimental programmes were carried out. The first investigation consisted of accelerated corrosion and concentric pull-out testing on unconfined concrete specimens. It was found that bond degradation only occurred where corrosion products caused expansive pressure, splitting cracks and a progressive loss of rib interlock. The reduction in bond depended upon the widths of the cracks, irrespective of the levels of corrosion. Surface crack widths resulted in better indicators of corrosion-induced bond degradation than conventional measures of corrosion such as mass loss or attack penetration. In the second investigation, a novel bond test set-up was developed to remove the parasitic effect of external confinement from the support reactions. The new geometry was adopted to study the effects of internal confinement on bond. The results showed that the dependence of anchorage capacity upon the concrete cover distance was not monotonic in the presence of confining reinforcement. Within a range of optimum cover-to-diameter ratios, small splitting cracks activated the transverse reinforcement and led to a bond strength uplift. In the third investigation, half-joint beams were tested in three-point bending to study the consequences of anchorage degradation on the overall behaviour of the component. Analytical predictions based on the lower bound theorem of plasticity were found to be overly conservative and did not capture the behaviour observed experimentally. This was attributed to a combination of local effects of greater anchorage capacity than predicted and global effects relating to alternative load-paths not taken into account by the predictive models. It was concluded that local deterioration led to a premature local failure of the half-joints, whilst the rest of the structural component was far from its ultimate behaviour and little redistribution had occurred. These conditions undermine the assumptions that underpin plasticity-based models for new design, thus reducing their accuracy when used for the assessment of existing structures in the presence of deterioration. The findings of this research contribute to the development of an effective assessment approach that correlates visual and measurable parameters on the outer surface of the concrete (e.g. crack widths), deterioration processes hidden inside the structure (e.g. bond degradation) and their structural consequences (e.g. overall strength reduction). Improved assessments could lead to enhanced asset management strategies that would reduce the safety risks, maintenance costs and environmental footprint of the infrastructure network., EPSRC; Highways England; Ove Arup & Partners.

The majority of surgical procedures treating joint disorders require a technique to realize a firm implant-to-tissue and/or a tissue-to-tissue fixation. Fixation methods have direct effects on survival, performance and integration of orthopedic implants This review paper gives an overview of novel fixation techniques that have been evaluated and optimized for orthopaedic joint implants and could be alternatives for traditional implant fixation techniques or inspirations for future design of joint implantation procedures. Method The articles were selected using the Scopus search engine. Key words referring to traditional fixation methods have been excluded to find potential innovative fixation techniques. In order to review the recent anchorage systems, only articles that been published during the period of 2010–2020 have been included. Results A total of 57 studies were analyzed. The result revealed that three main fixation principles are being employed: using mechanical interlockings, employing adhesives, and performing tissue-bonding strategies. Conclusion The development of fixation techniques demonstrates a transformation from the general anchoring tools like K-wires toward application-specific designs. Several new methods have been designed and evaluated, which highlight encouraging results as described in this review. It seems that mechanical fixations provide the strongest anchorage. Employing (bio)-adhesives as fixation tool could revolutionize the field of orthopedic surgery. However, the adhesives must be improved and optimized to meet the requirements of an anchorage system. Long-term fixation might be formed by tissue ingrowth approaches which showed promising results. In most cases further clinical studies are required to explore their outputs in clinical applications.

Objective: The aim of this study was to analyze the use of modified, cast splint Herbst appliances for the treatment of skeletal class II and as an alternative to surgical bite correction over a period of five years. Materials and methods: The patient cases all originate from the patients of the Department of Orthodontics at the University Medical Center of the Johannes Gutenberg University Mainz, Germany and the orthodontic practice Dres. Zöller, Kaiserslautern, Germany. Inclusion criteria were orthodontic treatment with the Herbst appliance and its modifications. The type of modification, number and frequency of the different modifications were determined on the basis of patient files, X-ray documents, photos and models. Results: Of a total of 2881 new admissions over a period of five years, 1751 patients came from the Department of Orthodontics at the University Medical Center of the Johannes Gutenberg University Mainz and 1130 from the orthodontic practice in Kaiserslautern. A total of 336 patients were treated with a Herbst appliance during the period mentioned. 14 (13 %) of the cases from the Herbst patient collective of the University Medical Center and 45 (19 %) of the cases from the orthodontic practice were classified as modifications. The following modifications could be determined in descending order: University Medical Center Mainz: Herbst for anchorage during space closure (65 %) > distalization (14 %) ≥ bar construction as a space maintainer (14 %) > Herbst applicance for anchoring for the adjustment of impacted teeth (7 %); orthodontic practice Kaiserslautern: Herbst appliance with quadhelix in the maxilla (42 %) > distalization (27 %) > space closure (15 %) > bar construction as a space maintainer (9 %) > adjustment of impacted teeth (7 %), multiple modifications occurred at 11 %. The combination of quadhelix and Herbst appliance as well as multiple modifications have not yet been used in the University Medical Center Mainz. As an alternative to dysgnathia surgery, 23 adult patients (> 18 years) from the University Medical Center and 22 from the orthodontic practice were treated with a Herbst appliance. Conclusion: Nearly 12 % of Herbst appliances are used in everyday orthodontic practice and almost 18 % of these are used with modification(s). The high anchoring quality and force-effect geometry of the Herbst appliance is suitable for combining and treating various other treatment tasks in addition to the classical treatment task of class II therapy.

The present studies were conducted to evaluate key serum proteins and other components that mediate anchorage-independent growth (3-D growth) of LNCaP prostate cancer cells as spheroids. The cells were cultured on ultra-low attachment plates in the absence and presence of fetuin-A and with or without extracellular vesicles. The data show that fetuin-A (alpha 2HS glycoprotein) is the serum protein that mediates 3-D growth in these cells. It does so by sequestering extracellular vesicles of various sizes on the surfaces of rounded cells that grow as spheroids. These vesicles in turn transmit growth signals such as the activation of AKT and MAP kinases in a pattern that differs from the activation of these key growth signaling pathways in adherent and spread cells growing in 2-D. In the process of orchestrating the movement and disposition of extracellular vesicles on these cells, fetuin-A is readily internalized in adhered and spread cells but remains on the surfaces of non-adherent cells. Taken together, our studies suggest the presence of distinct signaling domains or scaffolding platforms on the surfaces of prostate tumor cells growing in 3-D compared to 2-D.

Anchorage to concrete plays a significant role in various aspects of modern construction. The structural performance of anchors under direct tensile load can lead to failure by concrete cone breakout. Concrete related failure modes are quasi-brittle, and as such, they may develop without prior warning indications of damage, while it also exposes the bearing component to damage propagation. As such, an adequate reliability assessment of anchors against concrete cone failure is of high importance, and improved precision and minimisation of uncertainty in the predictive model are critical. This contribution develops predictive models for the tensile breakout capacity of fastening systems in concrete using the Gaussian Process Regression (GPR) and the Support Vector Regression (SVR) machine learning (ML) algorithms. The models were developed utilising a set of 864 experimental anchor tests. The efficiency of the developed models is assessed by statistical comparison to the state-of-practice semi-empirical predictive model, which is embedded in international design standards. Furthermore, the algorithms were evaluated based on a newly introduced Model Explainability concept based on Analogous Rational and Mechanical phenomena (MEARM). Finally, a discussion is provided regarding the developed ML models&rsquo, suitability for use as General Probabilistic Models in a reliability framework.

Objectives To compare torque recordings of immediately loaded orthodontic miniscrews between insertion time and different post-placement timepoints (2 weeks, 4 weeks and removal time, respectively). Setting and sample population Parallel trial with an allocation ratio of 1:1. Eligibility criteria were needs of fixed orthodontic treatment, no systemic disease and absence of using drugs altering bone metabolism. Material and methods Patients received miniscrews, 2.0 mm diameter and 10 mm length. All miniscrews underwent inter-radicular placement, and they were placed in the maxilla or in the mandible, palatally or buccally. No pre-drilling was performed. Miniscrews were loaded immediately after the insertion and were used for distalization, intrusion, extrusion, mesialization or indirect anchorage. Patients were randomly divided into three groups. For each patient, Maximum Insertion Torque (MIT) was evaluated at baseline. MIT was measured again after 2 weeks and after 4 weeks by tightening the screw a quarter of turn in Groups 1 and 2, respectively. At the end of the treatment, maximal removal torque was evaluated in Group 3. Torque variation with respect to insertion time was considered as the primary outcome. Baseline and longitudinal differences were tested using the linear mixed-effects (LME) model. Results Forty seven patients and 74 miniscrews were followed up. An association existed between maximum insertion torque and the observation time. A torque decrease of 26.9% and 30% after 2 weeks was observed for mandibular and maxillary miniscrews, respectively. After 1 month, torque values were similar to the baseline records. The overall success rate was 79.7%. No serious harm was observed. Conclusions Maximum insertion torque undergoes a loss during the first 2 weeks, and its values may depend on the insertion site and the anchorage purpose. Removal torque value is almost the same as the initial torque after 1 month.

Objective This outcome analysis study evaluated the actual positions of the orthodontic miniplate and miniplate anchoring screws (MPASs) and the risk factors affecting adjacent anatomic structures after miniplate placement in the mandibular incisal area. Methods Cone-beam computed tomographic images of 97 orthodontic miniplates and their 194 MPASs (diameter, 1.5 mm; length, 4 mm) in patients whose miniplates provided sufficient clinical stability for orthodontic treatment were retrospectively reviewed. For evaluating the actual positions of the miniplates and analyzing the risk factors, including the effects on adjacent roots, MPAS placement height (PH), placement depth (PD), plate angle (PA), mental fossa angle (MA), and root proximity were assessed using the paired t-test, analysis of variance, and generalized linear model and regression analyses. Results The mean PDs of MPASs at positions 1 (P1) and 2 (P2) were 2.01 mm and 2.23 mm, respectively. PA was significantly higher in the Class III malocclusion group than in the other groups. PH was positively correlated with MA and PD at P1. Of the 97 MPASs at P1, 49 were in the no-root area and 48 in the dentulous area; moreover, 19 showed a degree of root contact (19.6%) without root perforation. All MPASs at P2 were in the no-root area. Conclusions Positioning the miniplate head approximately 1 mm lower than the mucogingival junction is highly likely to provide sufficient PH for the P1- MPASs to be placed in the no-root area.

Mechanical failure, known as lodging, negatively impacts yield and grain quality in crops. Limiting crop loss from lodging requires an understanding of the plant traits that contribute to lodging‐resistance. In maize, specialized aerial brace roots are reported to reduce root lodging. However, their direct contribution to plant biomechanics has not been measured. In this manuscript, we use a non‐destructive field‐based mechanical test on plants before and after the removal of brace roots. This precisely determines the contribution of brace roots to establish a rigid base (i.e. stalk anchorage) that limits plant deflection in maize. These measurements demonstrate that the more brace root whorls that contact the soil, the greater their overall contribution to anchorage, but that the contributions of each whorl to anchorage were not equal. Previous studies demonstrated that the number of nodes that produce brace roots is correlated with flowering time in maize. To determine if flowering time selection alters the brace root contribution to anchorage, a subset of the Hallauer's Tusón tropical population was analyzed. Despite significant variation in flowering time and anchorage, selection neither altered the number of brace root whorls in the soil nor the overall contribution of brace roots to anchorage. These results demonstrate that brace roots provide a rigid base in maize and that the contribution of brace roots to anchorage was not linearly related to flowering time.

Introduction: There is an increasing number of adult patients with sequelae of periodontal diseases seeking orthodontic treatment to improve their occlusion and quality of life. However, it is important to highlight that the patient who has vertical bone loss has unique needs, arising from the frequent related pathological migrations. Therefore, it requires an individualized orthodontic treatment in terms of anchorage, biomechanics, and multidisciplinary planning, which raises doubts in the hierarchy of priorities and organization of the treatment plan. Objectives: It was proposed a stratified hierarchy of the needs of orthodontic-periodontal treatment in six levels, which were illustrated with examples of clinical cases in which biomechanical planning and a multidisciplinary approach made it possible to obtain a balanced occlusion, aesthetic improvement and stabilization of the results. Conclusion: Orthodontic treatment of periodontal patients with a multidisciplinary approach is increasingly frequent and should be planned individually, considering bone losses suffered by each patient. Respecting some limitations, it is possible to improve the level of bone insertion, smile aesthetics and masticatory function, to facilitate oral hygiene through the orthodontic treatment of adult patients with little bone support. It is also important to highlight that there are unique aspects in the orthodontic retention in these cases. RESUMO Introdução: É crescente o número de pacientes adultos portadores de sequelas de doenças periodontais que buscam tratamento ortodôntico para melhorar sua oclusão e qualidade de vida. Contudo, é importante destacar que o paciente que apresenta perda óssea vertical possui necessidades únicas, advindas das frequentes migrações patológicas relacionadas. Logo, requer um tratamento ortodôntico individualizado quanto a quesitos de ancoragem, biomecânica e planejamento multidisciplinar, o que gera dúvidas na hierarquização de prioridades e organização do plano de tratamento. Objetivos: Foi proposta uma hierarquização estratificada das necessidades do tratamento ortodôntico-periodontal em seis níveis, os quais foram ilustrados com exemplos de casos clínicos nos quais o planejamento biomecânico e a abordagem multidisciplinar possibilitaram a obtenção de uma oclusão equilibrada, melhora estética e estabilização dos resultados obtidos. Conclusão: O tratamento ortodôntico de pacientes periodontais com abordagem multidisciplinar é cada vez mais frequente e deve ser planejado de forma individualizada, considerando as perdas de inserção sofridas por cada paciente. Respeitando-se algumas limitações, é possível melhorar o nível de inserção óssea, a estética do sorriso e a função mastigatória, além de facilitar a higiene bucal, por meio do tratamento ortodôntico de pacientes adultos com pouco suporte ósseo. Também é importante destacar que há aspectos únicos na contenção ortodôntica desses casos.

Summary Objective The purpose of this study was to evaluate the biomechanical properties of miniscrews of 5 different lengths, 2 different diameters, and different combinations of insertion used for palatal skeletal anchorage. Materials and methods Twenty-four different combinations of a total of 120 miniscrews of two different diameters (2.0 mm and 2.3 mm) and five different lengths (9 mm, 11 mm, 13 mm and 15 mm) were tested at different angles of insertion (90° and 45°) and distances from a synthetic bone block (3 mm, 5 mm, 7 mm). Samples were fixed in an Instron Universal Testing Machine and a load was applied in single cantilever mode to the neck of each miniscrew. The stiffness and maximum load before permanent deformation were recorded. Model-based recursive partitioning testing (CART) was used to evaluate differences between groups. Results Significantly higher forces were necessary to deform miniscrews of diameter 2.3 mm than those of 2.0 mm, those inserted at an angle of 45° with respect to 90°, and at smaller distances between the miniscrew neck and block; in addition, the maximum load and stiffness increased with increasing screw length. Conclusion This in vitro experimental study showed strong correlations between deformation load and miniscrew geometry, insertion angle and distance from the synthetic block, results that should be considered when planning miniscrew insertion in order to reduce the risk of unwanted fracture.

Objective To analyze the clinical and radiographic results of patients with rhizarthrosis who underwent surgical treatment for resection of the trapezium bone using a fixation system with anchors and a non-absorbable suture. Methods Fifteen patients with a mean age of 60.26 years old were studied. Fourteen patients had type III rhizarthrosis and 1 had type II rhizarthrosis, according to the Eaton-Littler classification. Data on the professional activity, affected side, and hand dominance were collected and evaluated for the presence of pain, degree of joint movement of the radial abduction of the thumb, opposition, and palmar grip strength. The upper limb function was assessed using the Quick Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. The patients were subjected to pre and postoperative radiographic examinations, by which the scaphoid-first metacarpal height was measured using the oblique view of the hand. Suspensionplasty by fixation was then performed using a system of two 2.0 mm threaded bone anchors and a 2.0 mm Ethibond (Ethicon, Inc., Somerville, NJ, USA) suture wire. Finally, the trapezium bone was resected. Results The mean follow-up duration was 21.50 ± 5.02 months. The patients showed a mean score of 1.6 in the final evaluation using the visual analog scale. The degree of joint movement of the abduction of the thumb was on average 61.67° postoperatively and 59.73° preoperatively. There was an improvement in thumb opposition and a significant improvement in the upper limb function, as assessed using the Quick DASH method. The scaphoid-first metacarpal height had a proximal migration of ∼ 50% in the postoperative radiographs. The mean time to return to daily living activities was 20.7 days, 24.7 days to practical life activities, and 101.3 days to work activities. There was no correlation between the level of professional activity and the incidence of the disease. Conclusions Trapeziectomy and suspensionplasty, using an anchorage system and a non-absorbable suture, shows a significant improvement in pain, opposition, and function of the affected upper limb, and is efficient for the surgical treatment of rhizarthrosis. It allows for a rapid return to daily living activities with a low risk for complications.

Corrosion of the reinforcement in concrete structures affects their structural capacity. This problem affects many existing concrete bridges and climate change is expected to worsen the situation in future. At the same time, assessment engineers lack simple and reliable calculation methods for assessing the structural capacity of structures damaged by corrosion. This paper further develops an existing model for assessing the anchorage capacity of corroded reinforcement. The new version is based on the local bond stress-slip relationships from fib Model Code 2010 and has been modified to account for corrosion. The model is verified against a database containing the results from nearly 500 bond tests and by comparison with an empirical model from the literature. The results show that the inherent scatter among bond tests is large, even within groups of similar confinement and corrosion level. Nevertheless, the assessment model that has been developed can represent the degradation of anchorage capacity due to corrosion reasonably well. This new development of the model is shown to represent the experimental data better than the previous version; it yields similar results to an empirical model in the literature. In contrast to many empirical models, the model developed here represents physical behaviour and shows the full local bond stress-slip relationship. Using this assessment model will increase the ability of professional engineers to estimate the anchorage capacity of corroded concrete structures.

The use of headed reinforcement and hooked bars to reduce development length is restricted to bars loaded in tension only and shall not be considered effective in developing bars in compression according to the ACI-318 code. However, there are situations where a small development length in compression is required. This paper presents results of experimental study for assessing the use of dual headed bars to develop bars in compression as well as in tension. A total of 35 pullout tests and bar compression tests were performed. Parameters affecting the anchorage behavior of dual headed bars such as spacing between heads, concrete cover, concrete compressive strength, head area and confining reinforcement were studied. The results showed that bars with dual heads loaded in compression exhibited remarkable improvement in bond capacity. The parameters studied affected bond strength in compression loading in the same way as they affect bond on tension loading. No improvement is obtained for such dual headed bars loaded in tension, and even slight decrease in anchorage capacity was recorded for some specimens loaded in tension. However, the loss in anchorage capacity for bars with dual heads loaded in tension was very small in comparison to the gain attained in anchorage capacity in compression loading.

Three-dimensional (3D) root system architecture (RSA) is a predominant factor in anchorage failure in trees. Only a few studies have used 3D laser scanners to evaluate RSA, but they do not check the accuracy of measurements. 3D laser scanners can quickly obtain RSA data, but the data are collected as a point cloud with a large number of points representing surfaces. The point cloud data must be converted into a set of interconnected axes and segments to compute the root system traits. The purposes of this study were: (i) to propose a new method for easily obtaining root point data as 3D coordinates and root diameters from point cloud data acquired by 3D laser scanner measurement, and (ii) to compare the accuracy of the data from main roots with intensive manual measurement. We scanned the excavated root systems of two Pinus thunbergii Parl. trees using a 3D laser scanner and neuTube software, which was developed for reconstructing the neuronal structure, to convert the point cloud data into root point data for reconstructing RSA. The reconstruction and traits of the RSA calculated from point cloud data were similar in accuracy to intensive manual measurements. Roots larger than 7 mm in diameter were accurately measured by the 3D laser scanner measurement. In the proposed method, the root point data were connected as a frustum of cones, so the reconstructed RSAs were simpler than the 3D root surfaces. However, the frustum of cones still showed the main coarse root segments correctly. We concluded that the proposed method could be applied to reconstruct the RSA and calculate traits using point cloud data of the root system, on the condition that it was possible to model both the stump and ovality of root sections.

Introduction: The purpose of this prospective study was to analyze the efficiency of pendulum appliance for distalizing maxillary first molar while decreasing the anchorage loss by banding first and second premolar and making them one unit. Materials and Methods: The study group comprised of 20 patients (mean age 13 ± 2 years) who had skeletal Class I and Angle's Class II molar relation. Modified pendulum appliance was given to distalize maxillary first molar and to decrease the anchorage loss both first and second premolars were banded as a single unit by soldering a 19-gauge stainless steel wire. Then both skeletal and dental changes were measured on the pretreatment and posttreatment lateral cephalograms. Results: The maxillary molar was distalized, and a Class I molar relation was achieved in 3 ± 2 months. Maxillary first molar distalized by 4.48 mm in the region of dental crown by tipping distally an average of 8.5°. Both the premolars tipped distally significantly. Thus, by this modification, the anchor loss was minimized. Conclusion: It was concluded that the efficiency of pendulum appliance was increased by this modification, as the anchorage was increased, the space loss was minimized.

ObjectiveThe study conducted to assess the effects of a fixed functional appliance (Forsus Fatigue Resistant Device; 3M Unitek, Monrovia, CA, USA) on the mandible with three-dimensional (3D) finite element stress analysis.Materials and MethodsA 3D finite element model of mandible with miniplate at mandibular symphysis was prepared using SolidEdge software along with the plate geometry. The changes were deliberated with the finite element method, in the form of highest von Mises stress and maximum principal stress regions.ResultsMore areas of stress were seen in the model of the mandible at cortical bone in canine region at bone and miniplate interface.ConclusionsThis fixed functional appliance studied by finite element model analysis caused more von Mises stress and principal stress in both the cortical bone and the condylar region.

Objective: The aim of the present ex-vivo study was to evaluate the effect of the vertical placement angle of mini-implants on primary stability by analyzing maximum insertion torque (MIT). Methods: Mini-implants were placed in 30 human cadavers, inserted at either a 90° or 60° angle to the buccal surface of the maxillary first molar. Out of 60 self-drilling mini-implants used, half were of the cylindrical type and half were of the conical type. Primary stability was assessed by means of measuring the MIT. Data were subjected to analysis of variance (ANOVA) and Newman-Keuls tests. A significance level of 5% was adopted. Results: The MIT was higher for both mini-implant types when they were placed at a 90° angle (17.27 and 14.40 Ncm) compared with those placed at a 60° angle (14.13 and 11.40 Ncm). Conclusions: MIT values were differed according to the vertical mini-implant placement angle in the maxillary posterior area. Regardless of the type of mini-implant used, placement at a 90° angle resulted in a higher MIT. RESUMO Objetivo: o propósito deste estudo foi avaliar a influência do ângulo vertical de inserção dos mini-implantes sobre a estabilidade primária, a partir da análise do torque máximo de inserção (TMI). Material e Métodos: os mini-implantes foram instalados em 30 cadáveres humanos, em angulação de 90° ou 60° em relação à face vestibular de primeiros molares superiores. Os mini-implantes autoperfurantes (n = 60) utilizados foram 30 do tipo cilíndrico e 30 do tipo cônico. A estabilidade primária foi obtida por meio da quantificação do TMI. Os dados foram submetidos à análise de variância (ANOVA), seguida do teste de Newman-Keuls, considerando-se um nível de significância de 5%. Resultados: o TMI mostrou-se maior para ambos os tipos de mini-implante na inserção em 90o (17,27 e 14,40 Ncm) em comparação à inclinação de 60o (14,13 e 11,40 Ncm). Conclusões: o valor do TMI mostrou-se diferente de acordo com o ângulo de inserção vertical na região posterior da maxila. Independentemente do tipo de mini-implante utilizado, a inserção em 90° resultou em valores mais altos de TMI.

Objective: The main objective is to evaluate the effectiveness of en masse retraction with temporary skeletal anchorage devices (TSADs) versus two-step retraction with conventional anchorage (CA) in terms of the skeletal, dental, and soft-tissue variables, as well as the duration of retraction or overall orthodontic treatment. Materials and Methods: An electronic search of PubMed and nine other major databases for prospective, randomized controlled trials (RCTs) and clinical controlled trials (CCTs) was carried out between January 1990 and April 2018. The bibliography in each identified article was checked out. In addition, manual searching was performed in the same time frame in five major orthodontic journals. Adult patients undergoing fixed orthodontic treatment with extraction of maxillary premolars followed by an en masse retraction in the experimental group and two-step retraction of upper anterior teeth in the control group. Methodological index for nonrandomized studies for CCTs and Cochrane's risk of bias tool for RCTs were applied. Results: Four articles (two RCTs and two CCTs) were included in this review and all articles were appropriate for the quantitative synthesis. There was no significant difference between the en masse retraction and two-step retraction groups in terms of SNA, SNB, ANB, and MP-SN angles. Using TSADs gave significantly better results in terms of posterior anchorage and incisors inclination, and greater anterior teeth retraction in comparison with CA (standardized mean difference [SMD] = –3.03 mm, P < 0.001; SMD = 0.74°, P = 0.003; SMD = –0.46 mm, P = 0.03, respectively). En masse/TSAD combination caused a significantly greater increase in nasolabial angle, higher decrease in facial convexity angle, and greater lower lip retraction in comparison with two-step/CA combination (weighted mean difference = 4.73°, P = 0.007; P = 0.0435; SMD = –0.95 mm, P = 0.01, respectively). Conclusion: There is weak-to-moderate evidence that using either en masse/TSAD combination or two-step/CA combination would lead to similar skeletal improvement. There is a very weak-to-moderate evidence that using TSADs with en masse retraction would cause better posterior anchorage and incisors inclination, and greater anterior teeth retraction than using CA with two-step retraction. There is weak-to-moderate evidence that using en masse/TSAD combination would lead to a better improvement in the facial profile. According to the quality of evidence, we confirm the need for more well-conducted RCTs in the en masse retraction field.

The use of mechanical anchorage systems can delay or avoid premature failure of reinforced concrete (RC) structures with externally-bonded fiber-reinforced polymer (EB-FRP) laminates. This work reports the results of an experimental program aimed at studying the bond behavior of a metallic anchorage plate, typically used for pre-stressed EB-FRP systems. The overall experimental program comprised 17 concrete prisms with carbon fiber reinforced polymer (CFRP) laminates externally bonded to the concrete with mechanical anchorage at the end and where different levels of normal stress were applied. Direct shear tests were carried out using two configurations: (i) the steady-state tests, where the laminate was pulled out from the block with increasing force and constant temperature (20 ºC, 60 ºC and 80 ºC); (ii) and the transient tests, where the laminate was pulled out with constant force (0.36%, 0.45% and 0.54% of strain) and the temperature was gradually increased. Experimental results showed that the ultimate capacity of the mechanical anchorage can decrease by 44-59% depending on the temperature and level of normal stress., This work was supported by FEDER funds through the Operational Program for Competitiveness Factors – COMPETE and National Funds through FCT (Portuguese Foundation for Science and Technology) under the project FRPLongDur POCI-01-0145- FEDER-016900 (FCT PTDC/ECM-EST/1282/2014) and partly financed by the project POCI544 01-0145-FEDER-007633. The first author wishes also to acknowledge the grant SFRH/BD/98309/2013 provided by FCT. The second author acknowledges the Spanish Government (Ministerio de Educación, Cultura y Deporte) for the grant José Castillejo ref. CAS16/00288. Finally, the authors also like to thank all the companies that have been involved supporting and contributing for the development of this study, mainly: the S&P Clever Reinforcement Ibérica Lda. company for providing the laminates, the epoxy adhesive and metallic anchorage plates; the Hilti Portugal-Produtos e Serviços, Lda. company for providing the chemical bond agent to fix the anchor bolts; and the Tecnipor-Gomes & Taveira Lda company for producing the concrete blocks.

Aims and Objectives: The aim of this study was to determine the efficacy of mini-implants as adjuncts for intraoral anchorage units for en masse retraction of maxillary anterior teeth in bimaxillary dentoalveolar protrusion cases. Materials and Methods: The study sample consisted of 15 patients (10 females and 5 males). The samples were compared for anchorage loss with the implant-supported molar and conventional molar contralaterally in both the maxilla and mandible after six months of retraction period. The mini-implants used were 1.5 mm in diameter and 8 mm in length and were inserted in the first and third quadrant between the roots of second premolar and first molar under local anesthesia at an angle of 45°. For en masse retraction, active tiebacks with ligating (100g) were used bilaterally extending from molar hooks to J-hook on a 0.019” × 0.025” stainless steel arch wire. Lateral cephalograms were taken before and after retraction for assessing the loss of anchorage in maxillary and mandibular first molars. Results: Anchorage loss of 1.46 mm in the maxilla and 1.36 mm in mandible was found with conventional molar anchorage, whereas no statistically significant anchorage loss was found in the implant-supported molar side. Conclusion: Implant-supported molar side showed better anchorage compared with the conventional molar side. Hence, implant-supported molar can be used as an absolute anchorage unit in the en masse retraction of anterior teeth.

Acta neuropathologica 138(3), 477-495 (2019). doi:10.1007/s00401-019-02034-8, Published by Springer, Heidelberg

Plant mechanical failure, also known as lodging, is the cause of significant and unpredictable yield losses in cereal crops. Lodging occurs in two distinct failure modes - stalk lodging and root lodging. Despite the prevalence and detrimental impact of lodging on crop yields, there is little consensus on how to phenotype plants in the field for lodging resistance and thus breed for mechanically resilient plants. This review provides an overview of field-based mechanical testing approaches to assess stalk and root lodging resistance. These approaches are placed in the context of future perspectives. Best practices and recommendations for acquiring field-based mechanical phenotypes of plants are also presented.

Post-installed steel reinforcing bar connections carried out with anchoring mortars sufficiently qualified to fulfill the requirements for safety, serviceability, and durability of concrete structures are capable of developing bond behavior equivalent to cast-in-place steel reinforcing bars. Therefore, their design can be performed according to reinforced concrete design provisions. Post-installed anchorage technology offers fast and convenient solution to introduce new reinforcement in an existing reinforced concrete (RC) structural system, and hence serves as effective method for strengthening and upgrade of existing structures. The behavior of post-installed reinforcement depends on the existing condition of the concrete member. This paper addresses the aspects related to base material, installation, environment, and load conditions in service. This paper also comments on the qualification of anchoring mortars and provides information on the design of post-installed reinforcing bars as reinforcement (RC design perspective) or as anchorage (adhesive anchor design perspective) in the light of corresponding provisions necessary to achieve the same safety level in service compared to connections with cast-in steel reinforcing bars.

Bond of steel reinforcement to concrete was extensively studied worldwide during the last thirty years. However, few studies approach the evaluation of the effects of elevated temperatures on such load transfer mechanism and, in those, the presence of a sustained load applied prior to temperature increase is widely neglected. The present work investigates local bond properties between an ordinary carbon steel and an ordinary concrete when subjected to elevated temperatures, accounting as parameters the clear cover (and, more in general, the bar position), the bonded length and, mostly important, the effects of heating and loading sequence. Through test results and comparison with existing literature data it is shown that, for both pull-out and splitting failure modes, the effects of a sustained load on the evaluation of bond strength at a given temperature cannot be ignored for load levels higher than approximately sixty percent of the bond strength at cold state. Conditions for which the influence of the bonded length and of the bar position can be neglected in such assessment are also discussed.

Background and aims The tree resistance to uprooting is crucial to face wind damage in temperate forest. Tree anchorage varies considerably with site conditions, species, and tree age. Only few studies have focused on the influence of the site soil properties on the tree anchorage. With ongoing climate change, the soil hydrologic conditions are changing in Europe due to higher precipitations during winter, with possible higher risk of wind damage in forests. Methods This study investigates the role of soil hydrology on tree anchorage of Pinus pinaster in sandy soil with a combination of field experiments and simulations. Tree pulling experiments until root-soil system failure were performed for 12 Pinus pinaster of 14 years-old growing in podzol to measure the tree resistance to uprooting M c for two contrasted soil water conditions. In addition, simulations were conducted to analyze how M c changes during the progressive wetting of the layered soil. For that purpose, a new model was developed for M c . This model also includes a sub-model for the shear mechanical strengths of the sandy soil layers and their variation with soil water content. The model was calibrated with different data sets: (1) the M c -data obtained from the tree pulling experiments performed on 14 years-old Pinus pinaster; (2) the 3D root system architectures of the pulled trees; and (3) the soil shear mechanical strength as function of the soil water content measured in laboratory by direct shear tests and soil water retention curve measurements. After calibration, M c -calculations were performed when simulating a progressive soil wetting by water table increase or by water saturation front progression. Results Field-data and simulations show that M c depends little on soil water content outside the domain of complete soil saturation. Close to saturation, simulations show that M c decreases drastically up to 40 % of its value. This is specific to sandy soil whose mechanical strength is mainly due to the capillarity forces between grains. As illustrated by simulations, the anchorage resistance results from two components. The first friction component slightly increases with soil water content. The second suction component decreases little with soil water content and drops down at saturation when all the interstitial water in the soil porous network merges. Conclusions This loss of anchorage resistance at full saturation may increase considerably the risk of wind damage of forest growing in sandy soil as floods increase with climate change in Europe.

WOS: 000391134300003, This paper presents the results of an experimental study investigating the effects of anchorage systems used in externally bonded steel plates on the strength and ductility of reinforced concrete structures. In the literature, diagonal steel plates bonded to frames were designed to be more flexible than the connections to eliminate the possible effect of the connection flexibility. However, to better evaluate the performance of the strengthened structures, the strength and behavior of connections should also be considered. The purpose of this study was to experimentally investigate the effects of different connection types of steel plates bonded to the frame using anchors on the strengthened RC structures. For this purpose, eleven specimens were designed to simulate the interior and exterior connection behavior. Two of these were used as the control beams and remaining nine for the investigation of the functionality of the end steel plates. Experimental results show that the load carrying capacity of the strengthened beams is directly related to the connection types of the steel plates. For the interior connections, L-shaped end plates that were strengthened using steel anchors must have adequate stiffness to prevent its shape. While, for the exterior connections, the connection with three anchors carried more load than the other exterior connections.

Banding or bonding procedures have been the only means of attaching molar tubes onto the permanent molar teeth till date in the field of orthodontics. This clinical innovation aims to include the use of mini implant for the purpose of attaching the molar tubes thereby eliminating the iatrogenic effects of banding and bonding of the teeth.

Aim: The aim of this study was to compare the rate of canine retraction, the anchorage loss, and the change in the inclination of the first molars between molar and mini-implant anchorage. Objective: (1) To compare the rate of canine retraction between conventional molar anchorage and mini-implant anchorage in the maxilla and mandible. (2) To compare the amount of anchor loss between mini-implant-anchored and molar-anchored sides during canine retraction in the maxilla and mandible. Materials and Methods: Ten patients were included in the study. The implants were loaded immediately by applying a force of 100 g. Measurements were made in the pre-retraction and post-retraction lateral cephalograms. A line drawn vertically from the sella-nasion plane through the distal pterygomaxillary point was used as a reference line. Results: The mean rates of canine retraction were 0.95 and 0.82 mm/month in maxilla on the implant and molar sides, respectively, and were 0.81 and 0.76 mm/month in mandible on the implant and molar sides, respectively. The mean anchorage loss was 0.1 mm on the implant side and 1.3 mm on the molar side of the maxilla and 0.06 mm on the implant side and 1.3 mm on the molar side of the mandible. The mean change in molar inclination was 0.3° on implant side and 2.45° on molar side of the maxilla and was 0.19° on implant side and 2.69° on molar side of the mandible. Conclusions: Implant anchorage is an efficient alternative to molar anchorage.

Half-joint beams, also referred to as dapped-end beams, have been the subject of several studies, primarily focussing on the design optimisation of new reinforced concrete beams and bridge decks. Existing half-joint structures, however, often show signs of deterioration and can exhibit improper reinforcement detailing. In order to gain a better insight into the impact of local corrosion, anchorage cracking, limited amounts of provided shear reinforcement, and improper reinforcement detailing, a test program was designed. Full-scale tests on nine half-joint beams were performed. The results of the study show that even though the impact of an individual shortcoming on the load carrying capacity of reinforced concrete half-joint beams might not be substantial, inspectors and assessors should pay attention to the possibility of combined effects. When multiple deterioration processes are noted and/or questions are raised with respect to the reinforcement detailing, the impact on the load carrying capacity of the beam might be larger than the linear combination of the individual effects.

The Externally Bonded Reinforcement (EBR) technique using Carbon Fiber-Reinforced Polymers (CFRP) has been commonly used to strengthen concrete structures in flexure. The use of prestressed CFRP material offers several advantages well-reported in the literature. Regardless of such as benefits, several studies on different topics are missing. The present work intends to contribute to the knowledge of two commercially available systems that differ on the type of anchorage: (i) the Mechanical Anchorage (MA), and (ii) the Gradient Anchorage (GA). For that purpose, an experimental program was carried out with twelve slabs monotonically tested under displacement control up to failure by using a four-point bending test configuration. The effect of type of anchorage system (MA and GA), prestrain level (0 and 0.4%), width (50 mm and 80 mm) and thickness (1.2 mm and 1.4 mm) of the CFRP laminate, and the surface preparation (grinded and sandblasted) on the flexural response were the main studied parameters. Better performance was observed for the slabs: (i) with prestressed laminates, (ii) for the MA system, and (iii) with sandblasted surface preparation., This work is supported by FEDER funds through the Operational Program for Competitiveness Factors - COMPETE and National Funds through FCT - Portuguese Foundation for Science and Technology under the project FRPreDur - PTDC/ECM-EST/2424/2012. The authors also like to thank all the companies that have been involved supporting and contributing for the development of this study, mainly: S&P Clever Reinforcement Iberica Lda, S&P Clever Reinforcement Company (Switzerland), Tecnipor - Gomes & Taveira Lda., Via lam - Industrias Metalurgicas e Metalomecanicas, Lda., Hilti Portugal-Produtos e Servicos, Lda. The first and second authors wish also to acknowledge the grants SFRH/BD/98309/2013 and SFRH/BD/94850/2013, respectively, provided by FCT.