SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Åstrand Per) "

Sökning: WFRF:(Åstrand Per)

  • Resultat 1-50 av 50
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Engquist, Bo, et al. (författare)
  • Simplified methods of implant treatment in the edentulous lower jaw : A 3-year follow-up report of a controlled prospective study of one-stage versus two-stage surgery and early loading
  • 2005
  • Ingår i: Clinical Implant Dentistry and Related Research. - 1523-0899 .- 1708-8208. ; 7:2, s. 95-104
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Interest in the use of one-stage surgery and immediate loading of oral implants has lately been increasing. Purpose: The aim of this study was to compare the 3-year results of one-stage surgery versus two-stage surgery, early loading versus loading after a 3-month healing period, and the use of one-piece implants versus the use of two-piece implants. Materials and Methods: The study included 108 patients with edentulous mandibles. Each patient was treated with four Brånemark System® implants (Nobel Biocare AB, Göteborg, Sweden) and with full fixed prostheses. Patients were consecutively treated and were distributed in four groups: group A (one-stage surgery), group B (control group with two-stage surgery), group C (one-piece implants), and group D (early loading). In groups A and B Brånemark Standard implants and standard abutments were used. In group C the conical one-piece Brånemark implant was used, and in group D the patients had Brånemark System Mk III implants together with multiunit abutments. All patients were observed for 3 years. Results: Of the 432 inserted implants, 24 were lost. Survival rates in the three experimental groups ranged from 93.2 to 93.3% whereas the survival rate in group B (the control group with two-stage surgery) was 97.5%. The differences between the groups were not statistically significant. The changes in marginal bone level were measured from fixture insertion to the final follow-up at 3 years. The bone loss in group D (early loading) was significantly less than in group B (the control group) whereas there were no differences in marginal bone change between the other groups. Conclusions: Early loading seemed to give good results in the anterior part of the mandible. The survival rate of the early-loaded implants did not significantly differ from that of implants inserted with the conventional two-stage procedure, but the mean marginal bone loss around the surviving implants was less with early loading. ©2005 BC Decker Inc.
  •  
2.
  • Engquist, Bo, et al. (författare)
  • Simplified methods of implant treatment in the edentulous lower jaw. A controlled prospective study. Part I : one-stage versus two-stage surgery.
  • 2002
  • Ingår i: Clinical Implant Dentistry and Related Research. - 1523-0899 .- 1708-8208. ; 4:2, s. 93-103
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: The original protocol for Brσnemark System implants in the mandible was a two-stage procedure with 3 months healing time. With five or six implants and a cast framework of gold, the treatment is rather expensive, and simplified methods would be desirable. PURPOSE: The goal of this controlled serial study was to investigate the outcome of a simplified procedure with one-stage surgery, four Brσnemark implants, shortened healing time, and a new titanium-acrylic fixed full prosthesis. MATERIALS AND METHODS: Eighty-two patients were treated in three different groups at two specialist centers. All patients were provided with four implants, loaded with a Procera All-in-One bridge (Nobel Biocare, Gothenburg, Sweden) after 12 weeks. In group A (n = 30), one-stage surgery was combined with two-piece implants. In group B (n = 30), the control group, two-stage surgery and two-piece implants were used. In group C (n = 22), one-stage surgery was combined with one-piece implants. Marginal bone level was rated from radiographs at implant insertion, at baseline, and after 1 year. RESULTS: The survival rate after 1 year for group A was 93.3%, group B, 97.5%, and group C, 93.2%. The differences were not statistically significant. Between fixture insertion and baseline, the average bone loss for group A was 1.2 mm, group B, 1.3 mm, and group C, 1.3 mm. No complications in the form of bridge loosening or acrylic fractures were recorded during the first year. CONCLUSIONS: The survival rates and the marginal bone changes did not differ significantly between the one-stage groups and the control group. The survival rate and the marginal bone changes were similar for one-piece and two-piece implants. Four implants were sufficient to support full fixed prostheses in the mandibles. The Procera All-in-One bridges proved to be of high quality, and no complications were experienced. key words: endosseous implants, nonsubmerged implants, one-piece implants, prospective clinical study, submerged implants
  •  
3.
  • Engquist, Bo, et al. (författare)
  • Simplified methods of implant treatment in the edentulous lower jaw. Part II : Early loading
  • 2004
  • Ingår i: Clinical Implant Dentistry and Related Research. - 1523-0899 .- 1708-8208. ; 6:2, s. 90-100
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Most implant treatment is performed with a two-stage surgical procedure. A disadvantage of these implant treatments is that they are time-consuming. Purpose: The aim of the present study was to evaluate the results of early loading in the edentulous mandible and to compare those results with treatment results of one-stage surgery followed by a healing period and with two-stage surgery. Material and Methods: The material comprises four treatment groups with a total of 108 patients with edentulous lower jaws and 432 implants. All patients were treated with Brånemark implants (Nobel Biocare AB, Gothenburg, Sweden) with a turned surface and fixed prostheses in the lower jaw, supported by four implants. The patients in group A were treated with a one-stage procedure, a two-piece implant, and a 3-month healing period before loading. Group B (control group) had a two-stage procedure, a two-piece implant, and a 3-month healing period. Group C had a one-stage procedure, a one-piece implant, and a 3-month healing period. Group D was treated with a one-stage surgical procedure, a two-piece implant, and early loading (within 3 weeks). All patients were provided with a Procera® Implant Bridge (Nobel Biocare) with a framework made by computer-assisted milling of one piece of pure titanium. All patients have been followed up for 1 year. Results: The survival rates were 93.2 to 93.3% in the experimental groups and 97.5% in the control group. The difference was not statistically significant. The measurements of the marginal bone level demonstrated a mean bone loss of 0.8 mm between fixture insertion and the 1-year examination in patients with early loading (group D) whereas the bone loss in patients who underwent a healing period before loading was 1.3 to 1.6 mm. The difference between the control group and the group with early loading was significant. Conclusions: Survival rates for patients treated with a one-stage procedure were lower than survival rates for patients treated according to a "classical concept," but the differences were not statistically significant. There was no difference between treatment results with one-piece and two-piece implants. The implant loss in patients with early loading was probably caused by overloading, and careful supervision of occlusal loading is recommended. Early loading gave significantly less marginal bone loss when compared with two-stage surgery.
  •  
4.
  • Ahlqvist, Jan, Birger, 1952-, et al. (författare)
  • Osseointegrated implants in edentulous jaws: a 2-year longitudinal study.
  • 1990
  • Ingår i: International Journal of Oral & Maxillofacial Implants. - 0882-2786 .- 1942-4434. ; 5:2, s. 155-163
  • Tidskriftsartikel (refereegranskat)abstract
    • Osseointegrated implants in 50 edentulous jaws were studied during a 2-year observation period. The implant survival rate was 89% in the maxillae and 97% in the mandibles. The marginal bone loss averaged 1.7 mm in the maxillae and 1.1 mm in the mandibles. Most of this bone loss occurred during the first year. The bone loss was greater in jaws with a preoperatively minor resorption of the alveolar ridge than in those with moderate or advanced resorption. The bone loss was also greater at the medially positioned implants than at those more posterior.
  •  
5.
  • Engquist, Bo, et al. (författare)
  • Marginal bone reaction to oral implants : A prospective comparative study of Astra Tech and Brσnemark System implants
  • 2002
  • Ingår i: Clinical Oral Implants Research. - : Wiley. - 0905-7161 .- 1600-0501. ; 13:1, s. 30-37
  • Tidskriftsartikel (refereegranskat)abstract
    • In earlier studies of Astra Tech and Brσnemark System implants, high survival rates and small marginal bone changes have been demonstrated. The aim of this study was to compare the two systems, primarily with regard to marginal bone changes, but also with regard to other clinical variables of interest. The present paper describes the results after three years. Sixty-six patients were included in the study and randomly assigned to treatment with Astra Tech implants (n = 184) or Brσnemark System implants (n = 187). The marginal bone level was radiographically examined at fixture insertion, at abutment connection, at baseline (delivery of the prosthetic construction) and at 1- and 3-year follow-up examinations. Between fixture insertion and the baseline examination, the pattern of marginal bone resorption differed between the two systems. However, there was no significant marginal bone change between baseline and the 1-year examination or between the 1- and 3-year examinations. Nor were there any differences between the systems. The mean bone loss in the upper jaw between BL (baseline) and 3 years was 0.2▒0.3 mm for Astra Tech implants and 0.2▒0.1 mm for Brσnemark System implants. The corresponding figures for the lower jaw were 0.3▒0.2 mm and 0.2▒0.1 mm. The survival rate of Astra Tech implants was significantly higher (98.9%) than for Brσnemark System implants (95.2%). However, five of the nine implant losses in the Brσnemark group occurred in one patient. For that reason, this result must be interpreted with caution. The number of patients with implant losses did not differ significantly between the systems. Few complications were recorded up to 3 years.
  •  
6.
  • Engström, Lars-Magnus, 1938-, et al. (författare)
  • Olle Halldén : Nekrolog
  • 2005
  • Annan publikation (populärvet., debatt m.m.)abstract
    • Olle Halldén var en svensk pionjär och centralgestalt inom pedagogik och humaniora inom kroppsövningsområdet i Sverige. Han var utbildad till gymnastikdirektör och under många år lärare vid Kungl. Gymnastiska Centralinsitutet/Gymnastik- och idrottshögskolan i Stockholm. 
  •  
7.
  • Fermergard, R., et al. (författare)
  • Osteotome sinus floor elevation and simultaneous placement of implants - A 1-year retrospective study with astra tech implants
  • 2008
  • Ingår i: Clinical Implant Dentistry and Related Research. - : Wiley. - 1523-0899 .- 1708-8208. ; 10:1, s. 62-69
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The bone support for implants in the posterior part of the maxilla is often poor. This condition may be treated with augmentation of the maxillary sinus floor. The most common technique used is to elevate the sinus floor by inserting a bone graft through a window opened in the lateral antral wall, although less invasive techniques with osteotomes have been used since 1994. Purpose: The aim of this study was to evaluate the clinical and radiographic outcome of implants placed in the posterior maxilla with the osteotome sinus floor elevation (OSFE) technique without grafting. Materials and Methods: The study population comprised 36 consecutive patients in whom 53 implants were inserted with the OSFE technique. The indication for sinus floor elevation was that the bone height below the maxillary sinus was considered to be 10 mm or less. Results: The mean height of the alveolar process in the intended implant sites was 6.3 ± 0.3 mm, and the mean elevation of the sinus floor was 4.4 ± 0.2 mm. At the 1-year follow-up, two implants had been lost, both in edentulous patients. The remaining 51 implants inserted were in function, giving a 1-year cumulative survival rate of 96%. Implants used in single-tooth replacements and in partially edentulous cases had a 100% survival rate. The mean marginal bone level at the time of loading of the implants was 0.1 ± 0.04 mm below the reference point. One year later, the corresponding value was 0.5 ± 0.06 mm. The mean bone loss between the two examinations was 0.4 ± 0.05 mm. Conclusions: The OSFE technique, without bone grafts, was found to produce predictable results in the treatment of 36 patients with restricted bone volume in the posterior part of the maxilla. © 2007, Blackwell Publishing.
  •  
8.
  • Fermergard, Robert, et al. (författare)
  • Osteotome Sinus Floor Elevation without Bone Grafts - A 3-Year Retrospective Study with Astra Tech Implants
  • 2012
  • Ingår i: Clinical Implant Dentistry and Related Research. - : Wiley-Blackwell. - 1523-0899 .- 1708-8208. ; 14:2, s. 198-205
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The bone support for implants in the posterior part of the maxilla is often poor. This condition may be treated with augmentation of the maxillary sinus floor. The most common technique used is to elevate the sinus floor by inserting a bone graft through a window opened in the lateral antral wall. In 1994, a less-invasive technique using osteotomes was suggested by Summers. less thanbrgreater than less thanbrgreater thanPurpose: The aim of this study was to evaluate the clinical and radiographic outcome of implants placed in the posterior maxilla with the osteotome sinus floor elevation (OSFE) technique without grafting. less thanbrgreater than less thanbrgreater thanMaterials and Methods: The study population comprised 36 consecutive patients in whom 53 implants were inserted with the OSFE technique. The indication for sinus floor elevation was that the bone height below the maxillary sinus was considered to be 10 mm or less. less thanbrgreater than less thanbrgreater thanResults: The mean height of the alveolar process in the intended implant sites was 6.3 +/- 0.3 mm, and the mean elevation of the sinus floor was 4.4 +/- 0.2 mm. Two implants in edentulous patients were lost at the 1-year follow-up, and one more at the 3-year examination. The remaining 50 implants inserted were in function, giving a 3-year cumulative survival rate of 94%. Implants used in single-tooth replacements and in partially edentulous cases had a 100% survival rate. The marginal bone level at the time of loading of the implants was 0.1 +/- 0.04 mm below the reference point. One year later, the corresponding value was 0.5 +/- 0.06 mm. The mean bone loss between the two examinations was 0.4 +/- 0.05 mm. At the final examination after 3 years, the mean bone level was situated 0.6 +/- 0.09 mm below the reference point, indicating a nonsignificant change between 1 year and 3 years. less thanbrgreater than less thanbrgreater thanConclusions: The OSFE technique, without bone grafts, was found to produce predictable results in the treatment of 36 patients with restricted bone volume in the posterior part of the maxilla.
  •  
9.
  • Gundersen, Per Ole M., et al. (författare)
  • Metabolite Profiling of Ortho-, Meta- and Para-Fluorofentanyl by Hepatocytes and High-Resolution Mass Spectrometry
  • 2020
  • Ingår i: Journal of Analytical Toxicology. - : Oxford University Press. - 0146-4760 .- 1945-2403. ; 44:2, s. 140-148
  • Tidskriftsartikel (refereegranskat)abstract
    • New psychoactive substances are emerging on the illegal drug market. Synthetic opioids including fentanyl analogues are of special concern due to their high potency. This indicates the possibility of low drug concentrations in vivo and calls for sensitive analytical methods and identification of the most appropriate analytical targets. In this study the in vitro metabolism of ortho-, meta- and para-fluorofentanyl, three fluorinated derivatives of fentanyl, has been investigated using human hepatocytes and compared to the results from an authentic human urine sample. Based on knowledge on the metabolism of similar fentanyl analogues N-dealkylation and hydroxylation was hypothesized to be the most central pathways. The three fluorofentanyl isomers were incubated with pooled human hepatocytes at 1, 3 and 5 h. Liquid chromatography quadrupole time of flight mass spectrometry operating in data-dependent mode was used to analyse the hepatocyte samples, as well as the hydrolysed and non-hydrolysed authentic urine sample. Data were analysed by a targeted approach with a database of potential metabolites. The major metabolite formed in vitro was the N-dealkylation product norfluorofentanyl. In addition various hydroxylated metabolites, a N-oxide, dihydrodiol metabolites and a hydroxymethoxy metabolite were found. In total, 14 different metabolites were identified for each fluorofentanyl isomer. In the authentic urine sample, three metabolites were detected in addition to the ortho-fluorofentanyl parent compound, with hydroxymethoxy metabolite having the highest abundance followed by norfluorofentanyl and a metabolite hydroxylated on the ethylphenyl ring. This in vitro study showed that the metabolic pattern for ortho-, meta-, and para-fluorofentanyl was close to those previously reported for other fentanyl analogues. We suggest that the hydroxymethoxy metabolite and the metabolite hydroxylated on the ethylphenyl ring should be the metabolites primarily investigated in further studies to determine the most appropriate marker for intake of fluorofentanyl derivatives in urine drug screening for human subjects.
  •  
10.
  •  
11.
  • Harczuk, Ignat, 1987- (författare)
  • Atomic decomposition of molecular properties
  • 2016
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • In this thesis, new methodology of computing properties aimed for multipleapplications is developed. We use quantum mechanics to compute propertiesof molecules, and having these properties as a basis, we set up equations basedon a classical reasoning. These approximations are shown to be quite good inmany cases, and makes it possible to calculate linear and non-linear propertiesof large systems.The calculated molecular properties are decomposed into atomic propertiesusing the LoProp algorithm, which is a method only dependent on the overlapmatrix. This enables the expression of the molecular properties in the two-site atomic basis, giving atomic, and bond-centric force-fields in terms of themolecular multi-pole moments and polarizabilities. Since the original LoProptransformation was formulated for static fields, theory is developed which makesit possible to extract the frequency-dependent atomic properties as well. Fromthe second-order perturbation of the electron density with respect to an externalfield, LoProp is formulated to encompass the first order hyperpolarizability.The original Applequist formulation is extended into a quadratic formula-tion, which produces the second-order shift in the induced dipole moments of thepoint-dipoles from the hyperpolarizability. This enables the calculation of a to-tal hyperpolarizability in systems consisting of interacting atoms and molecules.The first polarizability α and the first hyperpolarizability β obtained via theLoProp transformation are used to calculate this response with respect to anexternal field using the quadratic Applequist equations.In the last part, the implemented analytical response LoProp procedureand the quadratic Applequist formalism is applied to various model systems.The polarizable force-field that is obtained from the decomposition of the staticmolecular polarizability α is tested by studying the one-photon absorption spec-trum of the green fluorescent protein. From the frequency dispersion of thepolarizability α(ω), the effect of field perturbations is evaluated in classicaland QM/MM applications. Using the dynamical polarizabilities, the Rayleigh-scattering of aerosol clusters consisting of water and cis–pinonic acid moleculesis studied. The LoProp hyperpolarizability in combination with the quadraticApplequist equations is used to test the validity of the model on sample wa-ter clusters of varying sizes. Using the modified point-dipole model developedby Thole, the hyper-Rayleigh scattering intensity of a model collagen triple-helix is calculated. The atomic dispersion coefficients are calculated from thedecomposition of the real molecular polarizability at imaginary frequencies. Fi-nally, using LoProp and a capping procedure we demonstrate how the QM/MMmethodology can be used to compute x-ray photoelectron spectra of a polymer.
  •  
12.
  •  
13.
  •  
14.
  • Hoffmann, Mikael, et al. (författare)
  • Risk talk : rhetorical strategies in consultations on hormone replacement therap
  • 2005
  • Ingår i: Health, Risk and Society. - Hants, UK : Carfax Publishing. - 1369-8575 .- 1469-8331. ; 5:2, s. 139-154
  • Tidskriftsartikel (refereegranskat)abstract
    • When analysing risk discussions in medical settings it is important to consider the specific activity type. In this qualitative study 20 first-time consultations by healthy women regarding hormone replacement therapy (HRT) in the menopause the risk discussion is asymmetrical with the doctors dominating. Despite being set up as a specific opportunity for women in the menopause to discuss problems and risks, it comes forth as a decision-making activity in a traditional medical setting. The consultations fulfil to a high extent the demands for informed decision making, but the risk discussions are recontextualised into a cost-benefit discourse with a typical implicit quantitative bias. The doctors use several different rhetorical strategies such as positive introduction of HRT, embedding drawbacks in positive introductions and/or exits thereby diminishing them. The word risk is avoided to a considerable extent and the term 'drawbacks' is used instead. The most obvious strategy is to move from the woman's symptoms to aspects of prevention, thus changing the discussion from the menopause and different strategies to cope with menopausal problems into a medically oriented discussion of pharmacological treatment alternatives. The 'change of life' in these talks is entirely conceptualised within a 'medical model'.
  •  
15.
  • Hoffmann, M, et al. (författare)
  • Risk talk: rhetorical strategies in consultations on hormone replacement therapy
  • 2003
  • Ingår i: Health, Risk & Society. - 1369-8575. ; 5, s. 139-154
  • Tidskriftsartikel (refereegranskat)abstract
    • When analysing risk discussions in medical settings it is important to consider the specific activity type. In this qualitative study 20 first-time consultations by healthy women regarding hormone replacement therapy (HRT) in the menopause the risk discussion is asymmetrical with the doctors dominating. Despite being set up as a specific opportunity for women in the menopause to discuss problems and risks, it comes forth as a decision-making activity in a traditional medical setting. The consultations fulfil to a high extent the demands for informed decision making, but the risk discussions are recontextualised into a cost-benefit discourse with a typical implicit quantitative bias. The doctors use several different rhetorical strategies such as positive introduction of HRT, embedding drawbacks in positive introductions and/or exits thereby diminishing them. The word risk is avoided to a considerable extent and the term 'drawbacks' is used instead. The most obvious strategy is to move from the woman's symptoms to aspects of prevention, thus changing the discussion from the menopause and different strategies to cope with menopausal problems into a medically oriented discussion of pharmacological treatment alternatives. The 'change of life' in these talks is entirely conceptualised within a 'medical model'.
  •  
16.
  • Hägglund, Gunnar, et al. (författare)
  • CPUP – från reaktiv till preventiv behandling av cerebral pares : Framgångsrik utveckling med CPUP - kombinerat uppföljningsprogram och kvalitetsregister
  • 2023
  • Ingår i: Lakartidningen. - 0023-7205. ; 120:46-47
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • CPUP is a combined follow-up program and national quality registry for cerebral palsy (CP). Since its inception in southern Sweden in 1994, CPUP has expanded geographically to cover all of Sweden, and similar programs are used in several northern European countries. Over 95% of all children with CP in Sweden, and a growing proportion of adults, are followed according to CPUP. The content of CPUP has been developed to involve most professions working with CP. CPUP has led to significant medical improvements. As an example, the percentage of individuals developing hip dislocation has decreased from 10% to 0.5%. The program's strengths include its interdisciplinary collaboration, user involvement, and the ability to inform and improve the quality of care systematically. Nevertheless, challenges include the need for ongoing funding and support. CPUP's success exemplifies how national quality registers can integrate into healthcare, enabling a shift from reactive to proactive care.
  •  
17.
  •  
18.
  • Jaen Ortega, A. A., et al. (författare)
  • On Understanding the Role of Exoskeleton Robots in Hand Rehabilitation : A Brief Review
  • 2022
  • Ingår i: Proceedings - 2022 8th International Engineering, Sciences and Technology Conference, IESTEC 2022. - : Institute of Electrical and Electronics Engineers Inc.. - 9781665498432 ; , s. 432-439
  • Konferensbidrag (refereegranskat)abstract
    • Hand rehabilitation has been widely studied since it affects the life quality and independence of those affected. Hand impairment can be caused by several conditions, among them strokes and other cerebrovascular accidents, affecting the capabilities of those who survive them in performing the activities of daily living (ADL). Rehabilitation seeks to restore the ability of a person to perform these crucial ADL. There is a current trend in using robotic rehabilitation and other industry 4.0 tools since it can provide a safe, intensive, and task-oriented at a relatively low cost, which can be combined with other technologies such as virtual and augmented reality, BCI, haptics, and others. Moreover, it can provide accessibility in the face of current panoramas such as COVID-19. Hand exoskeleton robots are one of the most extended robotic devices for rehabilitation. However, a design adapted to the patient's needs is necessary to achieve their capability fully and succeed in rehabilitation. One of the main challenges is that several considerations and parameters affect these devices' design and the broad approaches that can be followed. This brief review aims to understand and empathize as a source of inspiration during the design process of hand exoskeleton robots for rehabilitation.
  •  
19.
  • Jeppsson, Charlotte, et al. (författare)
  • A combination of bisphosphonate and BMP additives in impacted bone allografts
  • 2003
  • Ingår i: Acta Orthopaedica Scandinavica. - : Medical Journals Sweden AB. - 0001-6470. ; 74:4, s. 483-489
  • Tidskriftsartikel (refereegranskat)abstract
    • OP-1 increases bone ingrowth distance of new bone into allografts (TΣgil et al. 2000), but the bone density after incorporation may be reduced by an increase in resorption (H÷stner et al. 2000). Bisphosphonates inactivate osteoclasts and can be used to increase allograft bone density after incorporation (Aspenberg and ┼strand 2002). A combination of locally-applied bisphosphonate and OP-1 in the graft could therefore be expected to increase both new bone ingrowth and density. We tested this by using a rat bone chamber model. OP-1 alone increased the ingrowth distance of bone. Clodronate increased final bone density greatly, but reduced the ingrowth distance of new bone into grafts that were extremely impacted. This reduction was improved by adding OP-1. Regardless of graft density, combinations of OP-1 and clodronate included a high final bone density, but the ingrowth distances were shorter than with OP-1 alone. These data indicate that new bone and tissue ingrowth into a compacted graft depends on resorption and that resorption is a prerequisite for the stimulating effect of OP-1 in this experimental set-up. Although the problems associated with the use of OP-1 in impaction grafting may be solved by adding a bisphosphonate, some of the benefits of OP-1 can be lost.
  •  
20.
  • Johansson, Ulrika, 1974-, et al. (författare)
  • Assembly of functionalized silk together with cells to obtain proliferative 3D cultures integrated in a network of ECM-like microfibers
  • 2019
  • Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 9, s. 1-13
  • Tidskriftsartikel (refereegranskat)abstract
    • Tissues are built of cells integrated in an extracellular matrix (ECM) which provides a three-dimensional (3D) microfiber network with specific sites for cell anchorage. By genetic engineering, motifs from the ECM can be functionally fused to recombinant silk proteins. Such a silk protein, FN-silk, which harbours a motif from fibronectin, has the ability to self-assemble into networks of microfibers under physiological-like conditions. Herein we describe a method by which mammalian cells are added to the silk solution before assembly, and thereby get uniformly integrated between the formed microfibers. In the resulting 3D scaffold, the cells are highly proliferative and spread out more efficiently than when encapsulated in a hydrogel. Elongated cells containing filamentous actin and defined focal adhesion points confirm proper cell attachment to the FN-silk. The cells remain viable in culture for at least 90 days. The method is also scalable to macro-sized 3D cultures. Silk microfibers formed in a bundle with integrated cells are both strong and extendable, with mechanical properties similar to that of artery walls. The described method enables differentiation of stem cells in 3D as well as facile co-culture of several different cell types. We show that inclusion of endothelial cells leads to the formation of vessel-like structures throughout the tissue constructs. Hence, silk-assembly in presence of cells constitutes a viable option for 3D culture of cells integrated in a ECM-like network, with potential as base for engineering of functional tissue.
  •  
21.
  • Khan, Jamil, et al. (författare)
  • På väg mot ett hållbart energisystem
  • 2004
  • Ingår i: Miljö och hållbar utveckling: samhällsvetenskapliga perspektiv från en lundahorisont. ; , s. 383-407
  • Bokkapitel (övrigt vetenskapligt/konstnärligt)
  •  
22.
  • Kiapekos, Nikolaos, et al. (författare)
  • Primary surgery to prevent hip dislocation in children with cerebral palsy in Sweden : a minimum 5-year follow-up by the national surveillance program (CPUP)
  • 2019
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3674 .- 1745-3682. ; 90:5, s. 495-500
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose — Children with cerebral palsy (CP) have an increased risk of hip dislocation. Outcome studies after surgery to prevent hip dislocation in children with CP are usually retrospective series from single tertiary referral centers. According to the national CP surveillance program in Sweden (CPUP), hip surgery should preferably be performed at an early age to prevent hip dislocation. Preventive operations are performed in 12 different Swedish hospitals. We compared the outcomes between soft tissue release and femoral osteotomy in children with CP treated in these hospitals. Patients and methods — 186 children with CP underwent either adductor–iliopsoas tenotomy (APT) or femoral osteotomy (FO) as the primary, preventive surgery because of hip displacement. They were followed for a minimum of 5 years (mean 8 years) regarding revision surgery and hip migration. A good outcome was defined as the absence of revision surgery and a migration percentage (MP) < 50% at the latest follow-up. Logistic and Cox regression analysis were used to investigate the influence of age, sex, preoperative MP, Gross Motor Function Classification System (GMFCS) level, and CP subtype. Results — APT was performed in 129 (69%) children. After 5 years, the reoperation rate was 43%, and 2 children (2%) had an MP > 50%. For the 57 children who underwent FO, the corresponding figures were 39% and 9%. Of the potential risk factors studied, the outcome was statistically significantly associated with preoperative MP only in children who underwent APT, but not in those who underwent FO. None of the other factors were significantly associated with the outcome in the 2 procedure groups. Interpretation — Reoperation rates after preventive surgery are high and indicate the importance of continued postoperative follow-up. Age, sex, GMFCS level, and CP subtype did not influence the outcome significantly.
  •  
23.
  • Kubyshkina, Elena, 1990- (författare)
  • Ab initio modelling of interfaces in nanocomposites for high voltage insulation
  • 2018
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Dielectric nanocomposite materials have been experimentally proven to have properties that are beneficial in applications for efficient energy transport. However, today there are still no empirical models or rules that can predict the performance of a certain combination of materials in the nanocomposite, and there are also no definitive explanations of their dielectric behavior. A deeper understanding of the phenomena behind these materials' response to an applied electric field can open new possibilities for improvement of the insulating properties of nanocomposites.The goal of this work is to locate the key processes that are responsible for dielectric performance. The methodology of the study is based on ab initio technology, that relies solely on the knowledge of chemical and structural composition of the material. In this work, the charge-related properties of nanocomposite interfaces are studied. The primary material of the study is chosen to be polyethylene-based composite with magnesium oxide nanoparticles.The impact of the nanoparticle crystal surface termination and its silane treatment on the electronic structure of the interface between MgO and polyethylene are investigated here. Moreover, the effects of presence of carboxyl defect and water molecule near the interface are considered in this work as well.Based on the calculated electronic structure data, a model for charge dynamics is proposed. The model explains mechanisms for conductivity and space charge reduction in nanocomposites, but also predicts an increase in thermal stress and susceptibility for chemical defects. It is suggested here that the suppression mechanisms for space charge and conductivity in nanocomposites are inherently unstable and can also accelerate material aging.
  •  
24.
  • Lidbeck, Cecilia, et al. (författare)
  • The role of visual stimuli on standing posture in children with bilateral cerebral palsy
  • 2016
  • Ingår i: BMC Neurology. - : BioMed Central. - 1471-2377. ; 16:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: In children with bilateral cerebral palsy (CP) maintaining a standing position can be difficult. The fundamental motor task of standing independently is achieved by an interaction between the visual, somatosensory, and vestibular systems. In CP, the motor disorders are commonly accompanied by sensory and perceptual disturbances. Our aims were to examine the influence of visual stimuli on standing posture in relation to standing ability. Methods: Three dimensional motion analysis with surface electromyography was recorded to describe body position, body movement, and muscle activity during three standing tasks: in a self-selected position, while blindfolded, and during an attention-demanding task. Participants were twenty-seven typically-developing (TD) children and 36 children with bilateral CP, of which 17 required support for standing (CP-SwS) and 19 stood without support (CP-SwoS). Results: All children with CP stood with a more flexed body position than the TD children, even more pronounced in the children in CP-SwS. While blindfolded, the CP-SwS group further flexed their hips and knees, and increased muscle activity in knee extensors. In contrast, the children in CP-SwoS maintained the same body position but increased calf muscle activity. During the attention-demanding task, the children in CP-SwoS stood with more still head and knee positions and with less muscle activity. Conclusions: Visual input was important for children with CP to maintain a standing position. Without visual input the children who required support dropped into a further crouched position. The somatosensory and vestibular systems alone could not provide enough information about the body position in space without visual cues as a reference frame. In the children who stood without support, an intensified visual stimulus enhanced the ability to maintain a quiet standing position. It may be that impairments in the sensory systems are major contributors to the difficulties to stand erect in children with CP.
  •  
25.
  • Lindh-Åstrand, Lotta, et al. (författare)
  • Internet-delivered applied relaxation for vasomotor symptoms in postmenopausal women : lessons from a failed trial
  • 2015
  • Ingår i: Maturitas. - : Elsevier BV. - 0378-5122 .- 1873-4111. ; 80:4, s. 432-434
  • Tidskriftsartikel (refereegranskat)abstract
    • Internet-delivered therapies have a short history and promising results have been shown for several health problems, particularly for psychiatric conditions. This study was a first attempt to evaluate whether Internet-delivered applied relaxation for hot flushes in postmenopausal women may be useful. Due to a high drop-out rate the study was prematurely terminated after inclusion of approximately two thirds of calculated women. The Internet-delivered applied relaxation must probably be modified for such populations and settings before it can be used further. This article will discuss the benefits and pitfalls to learn in order to meet the challenges of future studies.Clinical Trial Registration Number: NCT01245907.
  •  
26.
  •  
27.
  •  
28.
  •  
29.
  •  
30.
  • Sjöqvist, Jonas, 1985- (författare)
  • Light interactions in flexible conjugated dyes
  • 2014
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • In this thesis methodological developments have been made for the description of flexible conjugated dyes in room temperature spectrum calculations.The methods in question target increased accuracy and efficiency by combining classical molecular dynamics (MD) simulations with time-dependent response theory spectrum calculations. For absorption and fluorescence spectroscopies a form of conformational averaging is used, where the final spectrum is obtained as an average of spectra calculated for geometries extracted from ground and excited state MD simulations. For infrared and Raman spectroscopies averaged spectra are calculated based on individual spectra, obtained for zero-temperature optimized molecular structures, weighted by conformational statistics from MD trajectories. Statistics for structural properties are also used in both cases to gain additional information about the systems, allowing more efficient utilization of computational resources. As it is essential that the molecular mechanics description of the system is highly accurate for methods of this nature to be effective, high quality force field parameters have been derived, describing the molecules of interest in either the MM3 or CHARMM force fields.These methods have been employed in the study of three systems. The first is a platinum(II) actylide chromophore used in optical power limiting materials, for which a ultraviolet/visible absorption spectrum has been calculated. The second is a family of molecular probes called luminescent conjugated oligothiophenes, used to detect and characterize amyloid proteins, for which both absorption and fluorescence spectra have been calculated. Finally, infrared and Raman spectra have been calculated for a group of branched oligothiophenes used in organic solar cells.In addition, solvation effects have been studied for conjugated poly\-eletrolytes in water, resulting in the development of two solvation models suitable for this class of molecules. The first uses a quantum meachanics/molecular mechanics (QM/MM) description, in which the solute mole\-cule is described using accurate quantum mechanical methods while the surrounding water molecules are described using point charges and polarizable point dipoles. The second discards the water entirely and removes the ionic groups of the solute. The QM/MM model provides highly accurate results while the cut-down model gives results of slightly lower quality but at a much reduced computational cost.Finally, a study of protein-dye interactions has been performed, with the goal of explaining changes in the luminescence properties of the LCO chromophores when in the presence of amyloid proteins. Results were less than conclusive.
  •  
31.
  • Telleus, Anna, et al. (författare)
  • Orthopedic surgical procedures in 3,305 children and young adults with cerebral palsy : a register-based cohort study
  • 2022
  • Ingår i: Acta Orthopaedica. - : Medical Journal Sweden AB. - 1745-3674 .- 1745-3682. ; 93, s. 472-477
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and purpose - Few reports have described the panorama of orthopedic surgeries that children with cerebral palsy (CP) undergo. We analyzed the risk of a first surgery, and describe the frequency of orthopedic surgeries in terms of age, sex, anatomical location, and Gross Motor Function Classification System (GMFCS) level in children and young adults with CP.Patients and methods - This was a register-based cohort study of 3,305 individuals followed until 2-25 years of age. We used data from 2 national Swedish registers: the CPUP CP surveillance program and the Swedish National Patient Register. Kaplan-Meier survival curves were calculated to describe the risk of undergoing a first orthopedic surgery, related to age.Results - We included data for 3,311 orthopedic operations in 1,717 surgical sessions. The percentage of children operated on before age 15 years increased from 22% (95% CI 19-26) for GMFCS level I to 70% (CI 64-75) for level V. Ankle and foot surgery was predominant as first surgery for GMFCS I-II, and hip and femur surgery for GMFCS IV-V. Spinal surgery occurred almost exclusively for GMFCS IV-V. Descriptive data showed repeated surgical sessions to be frequent for higher GMFCS levels.Interpretation - The risk of having a first orthopedic surgical treatment increased with increasing GMFCS level and was initiated at younger age in children with higher GMFCS level.
  •  
32.
  •  
33.
  • Tägil, Magnus, et al. (författare)
  • Systemic zoledronate precoating of a bone graft reduces bone resorption during remodeling
  • 2006
  • Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3674 .- 1745-3682. ; 77:1, s. 23-26
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Cartilage degeneration often occurs after osteosynthesis of a devascularized intermediary fragment in a joint fracture, in mosaicplasty or in whole-joint toe-to-finger transplantation. Hypothetically, the degeneration is secondary to a collapse of the transferred subchondral bone as it remodels during high mechanical load. Bisphosphonates are used to reduce resorption of necrotic bone. We tested a systemic pretreatment before harvesting the graft in order to protect the bone and cartilage against collapse and secondary arthrosis. Methods: Rats were given one zoledronate injection and bone grafts were harvested. The grafts were frozen, thawed and placed into bone chambers, and implanted into another batch of rats. Graft resorption and new bone formation was measured by histomorphometric analysis and compared with untreated grafts. Results: In the remodeled area of the controls, the graft was almost totally resorbed and replaced by bone marrow. In the zoledronate-treated specimens, the graft remained and the graft trabeculas were lined with new bone. By histomorphometry, the total amount of bone (graft plus new bone) within the remodeled area was 16% in the zoledronate-treated grafts and 5% in the controls (p = 0.003). Interpretation: A bone graft can be pretreated with bisphosphonate and remain protected against resorption once implanted again. Copyright© Taylor & Francis 2006. all rights reserved.
  •  
34.
  • Åstrand, Jörgen, et al. (författare)
  • A rat model for testing pharmacologic treatments of pressure-related bone loss
  • 2003
  • Ingår i: Clinical Orthopaedics and Related Research. - : Ovid Technologies (Wolters Kluwer Health). - 0009-921X. ; :409, s. 296-305
  • Tidskriftsartikel (refereegranskat)abstract
    • Fluid pressure, instability, or particles have been suggested to initiate the process leading to loosening of prosthetic implants. In a rat model where bone resorption is caused by oscillating fluid pressure, the resorptive response seems much stronger than the response that can be induced by particles or instability. Bone resorption is caused by osteoclasts. It has been suggested that the formation of osteoclasts is influenced by tumor necrosis factor-alpha, which can be blocked by etanercept. Osteoclasts can be inactivated with bisphosphonates, which bind to bone and inactivate osteoclasts when the bisphosphonate-containing bone is resorbed. Bone formation can be increased dramatically by intermittent parathyroid hormone treatment, especially at sites with high bone turnover. This might compensate for increased osteoclastic activity. Forty-two rats received a plate implant, by which fluid pressure was applied to a bone surface by compressing a soft tissue membrane. Eight rats were treated with etanercept 0.75 mg/kg/day, six rats were treated with alendronate 205 mug/kg/day, six rats received saline, and six rats were nonpressurized controls. Nine rats received intermittent parathyroid hormone treatment with nine separate controls. The area of bone resorption under the implant was evaluated by histomorphometry. Alendronate-treated rats showed less bone resorption, but etanercept, intermittent parathyroid hormone treatment, or saline did not reduce the fluid pressure-induced bone resorption. This model is a comparatively simple way of testing pharmacologic reduction of local bone resorption in vivo.
  •  
35.
  • Åstrand, Jörgen, et al. (författare)
  • Bone allografts pretreated with a bisphosphonate are not resorbed
  • 2002
  • Ingår i: Acta Orthopaedica Scandinavica. - : Medical Journals Sweden AB. - 0001-6470. ; 73:1, s. 20-23
  • Tidskriftsartikel (refereegranskat)abstract
    • Bisphosphonates bind to bone surfaces and inactivate osteoclasts when they start to resorb the bone. Therefore, immersion of a bone graft in a bisphosphonate solution before implantation may protect it from resorption. We implanted frozen cancellous bone allografts into bilateral bone chambers for 6 weeks in 10 rats. One graft in each pair had been immersed in an alendronate solution (1 mg/mL) for 10 minutes, and then rinsed in saline. Controls underwent the same treatment with saline only. Results were evaluated with histomorphometry. Control grafts were almost entirely resorbed, but alendronate-treated grafts seemed intact. In the treated specimens, two thirds of the space behind the bone ingrowth frontier consisted of graft or host bone, but in the controls, only one fifth. Local graft treatment with a bisphosphonate before insertion seems to be risk-free, and may prevent mechanical graft failure due to resorption in patients.
  •  
36.
  •  
37.
  • Åstrand, Jörgen, et al. (författare)
  • Reduction of instability-induced bone resorption using bisphosphonates: high doses are needed in rats.
  • 2002
  • Ingår i: Acta Orthopaedica Scandinavica. - : Medical Journals Sweden AB. - 0001-6470. ; 73:1, s. 24-30
  • Tidskriftsartikel (refereegranskat)abstract
    • Bone resorption associated with prosthetic loosening can be reduced by giving bisphosphonates since they bind to bone surfaces and inactivate osteoclasts when bisphosphonate-containing bone is resorbed. During loosening, an increase in osteoclastic activity can be triggered by mechanical instability, fluid pressure or wear particles. We used a rat model in which a titanium surface can be made to slide over a bone surface and cause instability-induced bone resorption. 111 rats were operated on with a plate implant and treated with alendronate or clodronate injections in different doses or saline controls. After 4 weeks of osseointegration, the plate was moved during 2 weeks and the findings evaluated with histomorphometry. The percentage of persisting bone-metal contact and the soft tissue area at the interface were measured to estimate bone loss. Low or intermediate doses of the bisphosphonates increased the ash weight of untraumatized bone, but did not inhibit resorption at the unstable interface. Only rats treated with the highest doses of alendronate or clodronate had more bone-metal contact than controls. Instability-induced bone resorption therefore seems to be reduced by bisphosphonates, but higher doses are needed to obtain this effect than to reduce bone resorption associated with normal remodeling of untraumatized bone.
  •  
38.
  • Åstrand, Jörgen, et al. (författare)
  • Systemic alendronate prevents resorption of necrotic bone during revascularization. A bone chamber study in rats
  • 2002
  • Ingår i: BMC Musculoskeletal Disorders. - : Springer Science and Business Media LLC. - 1471-2474. ; 3
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Avascular necrosis of bone (osteonecrosis) can cause structural failure and subsequent deformation, leading to joint dysfunction and pain. Structural failure is the result of resorption of necrotic bone during revascularization, before new bone has formed or consolidated enough for loadbearing. Bone resorption can be reduced by bisphosphonates. If resorption of the necrotic bone could be reduced during the revascularization phase until sufficient new bone has formed, it would appear that structural failure could be avoided. Methods: To test whether resorption of necrotic bone can be prevented, structural grafts were subjected to new bone ingrowth during systemic bisphosphonate treatment in a rat model. Results: In rats treated with alendronate the necrotic bone was not resorbed, whereas it was almost entirely resorbed in the controls. Conclusion: Systemic alendronate treatment prevents resorption of necrotic bone during revascularization. In patients with osteonecrosis, bisphosphonates may therefore prevent collapse of the necrotic bone.
  •  
39.
  • Åstrand, Jörgen, et al. (författare)
  • Systemic alendronate prevents resorption of necrotic bone duringrevascularization. A bone chamber study in rats
  • 2002
  • Ingår i: BMC Musculoskeletal Disorders. - : Springer Science and Business Media LLC. - 1471-2474. ; 3
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Avascular necrosis of bone (osteonecrosis) can cause structural failure and subsequent deformation, leading to joint dysfunction and pain. Structural failure is the result of resorption of necrotic bone during revascularization, before new bone has formed or consolidated enough for loadbearing. Bone resorption can be reduced by bisphosphonates. If resorption of the necrotic bone could be reduced during the revascularization phase until sufficient new bone has formed, it would appear that structural failure could be avoided. Methods: To test whether resorption of necrotic bone can be prevented, structural grafts were subjected to new bone ingrowth during systemic bisphosphonate treatment in a rat model. Results: In rats treated with alendronate the necrotic bone was not resorbed, whereas it was almost entirely resorbed in the controls. Conclusion: Systemic alendronate treatment prevents resorption of necrotic bone during revascularization. In patients with osteonecrosis, bisphosphonates may therefore prevent collapse of the necrotic bone.
  •  
40.
  • Åstrand, Jörgen, et al. (författare)
  • Systemic zoledronate treatment both prevents resorption of allograft bone and increases the retention of new formed bone during revascularization and remodelling. A bone chamber study in rats
  • 2006
  • Ingår i: BMC Musculoskeletal Disorders. - : Springer Science and Business Media LLC. - 1471-2474. ; 7
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: In osteonecrosis the vascular supply of the bone is interrupted and the living cells die. The inorganic mineral network remains intact until ingrowing blood vessels invade the graft. Accompanying osteoclasts start to resorb the bone trabeculae and gradually replace the bone. If the osteonecrosis occurs in mechanically loaded parts, like in the subchondral bone of a loaded joint, the remodelling might lead to a weakening of the bone and, in consequence to a joint collapse. Systemic bisphosphonate treatment can reduce the resorption of necrotic bone. In the present study we investigate if zoledronate, the most potent of the commercially available bisphosphonates, can be used to reduce the amount or speed of bone graft remodeling. Methods: Bone grafts were harvested and placed in a bone chamber inserted into the tibia of a rat. Host tissue could grow into the graft through openings in the chamber. Weekly injections with 1.05 μg zoledronate or saline were given subcutaneously until the rats were harvested after 6 weeks. The specimens were fixed, cut and stained with haematoxylin/eosin and used for histologic and histomorphometric analyses. Results: By histology, the control specimens were almost totally resorbed in the remodeled area and the graft replaced by bone marrow. In the zoledronate treated specimens, both the old graft and new-formed bone remained and the graft trabeculas were lined with new bone. By histomorphometry, the total amount of bone (graft+ new bone) within the remodelled area was 35 % (SD 13) in the zoledronate treated grafts and 19 % (SD 12) in the controls (p = 0.001). Also the amount of new bone was increased in the treated specimens (22 %, SD 7) compared to the controls (14 %, SD 9, p = 0.032). Conclusion: We show that zoledronate can be used to decrease the resorption of both old graft and newformed bone during bone graft remodelling. This might be useful in bone grafting procedure but also in other orthopedic conditions, both where necrotic bone has to be remodelled i.e. after osteonecrosis of the knee and hip and in Perthes disease, or in high load, high turnover conditions like delayed union, periprosthetic osteolysis or bone lengthening operations. In our model an increased net formation of new bone was found which probably reflects that new bone formed was retained by the action of the bisphosphonates rather than a true anabolic effect. © 2006 Åstrand et al, licensee BioMed Central Ltd.
  •  
41.
  •  
42.
  •  
43.
  • Åstrand, Per, 1935-, et al. (författare)
  • Astra Tech and Brånemark system implants: a 5-year prospective study of marginal bone reactions.
  • 2004
  • Ingår i: Clinical oral implants research. - : Wiley. - 0905-7161 .- 1600-0501. ; 15:4, s. 413-20
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper describes the 5-year results of a comparative study between Astra Tech and Brånemark system implants. The aim was to compare the systems primarily with regard to bone level changes, and also with regard to other variables of interest. Sixty-six patients with edentulous jaws were included in the study. Randomisation schedules were used to allocate the patients to the two implant systems. 184 Astra Tech implants with a titanium-blasted surface and 187 Brånemark implants with a turned surface were used. The implants were inserted with a two-stage technique and the insertion followed the routines for the respective implant system. All patients were provided with full-arch fixed bridges. All patients were followed up with clinical and radiographic examinations from fixture insertion to the 5-year follow-up. The total mean bone level change in the upper jaw between fixture insertion and the 5-year examination was -1.74+/-0.45 mm at the Astra implants and -1.98+/-0.21 at the Brånemark implants. The corresponding values for the lower jaw were -1.06+/-0.19 for Astra and -1.38+/-0.17 for Brånemark. The major postoperative changes of the marginal bone level took place between fixture insertion and baseline. During this period, there was also a different pattern of bone remodelling between the implant systems. Between baseline (prosthesis connection) and the 5-year examination, the marginal bone level changes were small, with no difference between the implant systems. The implant stability was examined with the supraconstructions removed. At the 5-year examination, the survival rate for Astra Tech implants was 98.4% and for the Brånemark implants it was 94.6%. The difference was not statistically significant.
  •  
44.
  • Åstrand, Per, et al. (författare)
  • Implant treatment of patients with edentulous jaws : a 20-year follow-up
  • 2008
  • Ingår i: Clinical Implant Dentistry and Related Research. - : Wiley-Blackwell. - 1523-0899 .- 1708-8208. ; 10:4, s. 207-217
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Implant-supported prostheses are today often used in rehabilitation of partially or totally edentulous patients. Both patients and the dental profession often regard implant treatment as successful in a life perspective. Therefore, studies with a long-term follow-up are important.PURPOSE: The aim was to investigate the outcome of implant treatment with fixed prostheses in edentulous jaws after 20 years, with special reference to survival rate of implants and prostheses and frequency of peri-implantitis.MATERIALS AND METHODS: The patient material was a group of patients treated in the early 1980s. The original patient group comprised the first 48 consecutive patients treated with implant-supported prostheses at Umeå University. All patients were edentulous in one or two jaws. The patients had a mean age at the implant insertion of 54.3 years (range 40-74). At the planning of this study 20 years after treatment, 19 of the 48 patients were found to be deceased. Of the 29 patients still alive, 21 patients with altogether 23 implant-supported prostheses could be examined clinically and radiographically. All patients were treated ad modum Brånemark (Nobel Biocare AB, Göteborg, Sweden) with a two-stage surgical procedure. The implants had a turned surface. Abutment connections were performed 3 to 4 months after fixture insertion in the mandible, and after a minimum of 6 months in the maxilla. The prostheses were fabricated with a framework of gold alloy and acrylic artificial teeth.RESULTS: The 21 patients (with 23 implant prostheses) examined had at the time of treatment got 123 implants (27 in the upper jaw and 96 in the lower jaw) inserted. Only one of these implants had been lost (about 2 years after loading) giving a survival rate of 99.2%. Very small changes occurred in the marginal bone level. Between the 1 and 20-year examinations, the mean bone loss was 0.53 mm and the mean bone level at the final examination was 2.33 mm below the reference point.CONCLUSIONS: This follow-up over two decades of implant-supported prostheses demonstrates a very good prognosis for the treatment performed. The frequencies of peri-implantitis, implant failures, or other complications were very small, and the original treatment concept with a two-stage surgery and a turned surface of the implants will obviously give very good results.
  •  
45.
  •  
46.
  • Åstrand, Per, 1935-, et al. (författare)
  • Nonsubmerged and submerged implants in the treatment of the partially edentulous maxilla.
  • 2002
  • Ingår i: Clinical Implant Dentistry and Related Research. - 1523-0899 .- 1708-8208. ; 4:3, s. 115-127
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Dental implants vary in design and surfaces. In addition, different surgical techniques have been used for implant insertion. The ITI Dental Implant System (Straumann AG, Waldenburg, Switzerland) has always required a one-stage technique, whereas the Brσnemark System (Nobel Biocare AB, Gothenburg, Sweden) requires a two-stage technique. PURPOSE: The aim of this study is to compare the outcome of fixed partial bridges in the maxilla supported by both ITI and Brσnemark implants in a split-mouth design. MATERIALS AND METHODS: Twenty-eight patients with a residual anterior dentition in the maxilla were included in this split-mouth study. The Brσnemark implants were used on one side and the ITI implants on the other side of the residual dentition according to a randomization procedure. A blocking size of four was used, giving equal probability of placing ITI or Brσnemark implants in the right or left side of the jaw. The surgical and prosthetic procedures followed the guidelines given by the manufacturers. The prosthetic treatment with the two-implant systems was performed at the same time, and for that reason the healing period was 6 months for both systems. The observation period for all patients was 1 year after loading. RESULTS: Two Brσnemark implants (in one patient) were lost before loading, and one ITI implant was lost 1 year after loading. There was no significant difference in survival rate. Radiographic examination of the bone level was performed at the time of delivery of the bridge and after 1 year. The mean marginal bone level at baseline was situated 1.9 mm from the reference point for the Brσnemark implants and 1.5 mm for the ITI implants. With regard to the insertion depth used, these bone levels indicate that bone loss had taken place before baseline. However, between baseline and the 1-year examination, there was no significant change of the marginal bone (0.2 +/- 0.08 mm at the Brσnemark implants and 0.1 +/- 0.11 mm at the ITI implants). The difference between results with the two implants was not statistically significant. Crater-form bone destructions were seen at some ITI implants, indicating periimplantitis. However, at only two implants were there clinical signs of periimplantitis. CONCLUSIONS: No significant difference in survival rate or in marginal bone change could be demonstrated between the two systems. At some ITI implants (18%), crater-form bone loss was observed.
  •  
47.
  •  
48.
  • Åstrand, Per-Olof, 1922- (författare)
  • Fysiologiska institutionens tillkomst och utveckling
  • 1988
  • Ingår i: Kungl Gymnastiska centralinstitutet : Gymnastik- och idrottshögskolan i Stockholm : 1963-1988. - Stockholm : Gymnastik- och idrottshögskolan. - 9179703291 ; , s. 196-239
  • Bokkapitel (populärvet., debatt m.m.)abstract
    • Kapitlet beskriver Fysiologiska institutionen vid GCI/GIH under åren 1938 till 1988.
  •  
49.
  • Åstrand, Per-Olof, 1923-, et al. (författare)
  • Född Till rörelse : En bok om kost och motion
  • 2011
  • Bok (populärvet., debatt m.m.)abstract
    • Praktiskt taget alla vuxna svenskar anser att regelbunden motion är bra för hälsa och arbetsförmåga. Vi är också upplysta om hur våra matvanor, alkoholintag och rökning påverkar vår hälsa. Varför är det då en minoritet som har en livsstil som styrs av kunskap och förnuft? Finns svaret förankrat i vårt biologiska arv? Hur levde våra förfäder? Att sitta still i flera timmar utan att röra sig alls utgör en risk för utveckling av hjärt- och kärlsjukdom, cancer och annan ohälsa, trots att man kanske motionerar ett par gånger i veckan. Den fysiologiska förklaringen är den att om inte musklerna får arbeta regelbundet, om än mycket lite, så påverkas viktiga processer i musklerna, som sedan påverkar hela kroppen. Det räcker att regelbundet resa sig och gå en liten bit för att undvika de negativa effekterna av långvarigt sittande.I Född till rörelse kan du läsa om faktorer som har betydelse för vår kondition och hälsa. Varför är det så viktigt att vi rör på oss? Hur kan man motverka eller mildra effekten av vissa sjukdomar? Vad innebär det att vara fysiskt aktiv? Hur ska man träna och hur jobbigt bör det vara?
  •  
50.
  • Åstrand, Per, et al. (författare)
  • Tapered implants in jaws with soft bone quality : a clinical and radiographic 1-year study of the Brånemark System Mark IV fixture.
  • 2003
  • Ingår i: Clinical Implant Dentistry and Related Research. - 1523-0899 .- 1708-8208. ; 5:4, s. 213-218
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: The survival rate of oral implants in soft-quality bone has been demonstrated to be inferior to that of implants inserted in good-quality bone. A possible way to increase the survival rate in soft-quality bone may be to use a tapered implant. Such an implant has been developed and manufactured by Nobel Biocare AB, Gothenburg, Sweden. So far, there have been only a few publications regarding this implant. PURPOSE: The aim of the study was to compare the outcome of using the tapered Brånemark System Mark IV fixture with the outcome of using earlier Brånemark fixtures in a controlled prospective study. MATERIALS AND METHODS: The study was performed as a multicenter study including seven specialist centers. The material consisted of 40 patients in need of implant-supported bridges in the maxilla. Twenty-five patients belonged to the test group, in which the tapered Mark IV implants were inserted, and 15 patients belonged to the control group, in which Brånemark Standard or Mark II implants were used. The patients were allocated to the test group or the control group according to randomization schedules. The implants were inserted according to the guidelines for Brånemark implants. A two-stage surgical protocol was used, and abutment connection was made 6 months after fixture insertion. The test group comprised 97 Mark IV implants, and the control group made up 92 implants. The prosthetic procedure followed the guidelines for Brånemark implants, and all patients were provided with full fixed maxillary bridges. The patients were followed up with clinical and radiographic records for 1 year after loading. RESULTS: The survival rate was 96.9% for the Mark IV implants and 98.9% for the control implants. There was no significant difference between the two groups. There was a mean marginal bone loss of 0.2 mm during the observation period, and there was no difference between test implants and control implants. CONCLUSIONS: With regard to survival rate and marginal bone level changes, no differences could be demonstrated between the Mark IV tapered implant and the Brånemark implants used earlier. However, compared with earlier results of Brånemark implants in soft-quality bone, the Mark IV implant demonstrated an improved survival rate.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-50 av 50
Typ av publikation
tidskriftsartikel (40)
doktorsavhandling (4)
annan publikation (2)
bokkapitel (2)
bok (1)
konferensbidrag (1)
visa fler...
visa färre...
Typ av innehåll
refereegranskat (39)
övrigt vetenskapligt/konstnärligt (6)
populärvet., debatt m.m. (5)
Författare/redaktör
Åstrand, Per (9)
Aspenberg, Per, 1949 ... (7)
Karlsson, Ulf (4)
Tägil, Magnus (4)
Aspenberg, Per (4)
Lindh-Åstrand, Lotta (3)
visa fler...
Linell, Per (2)
Gunne, Johan (2)
Schantz, Peter, 1954 ... (2)
Carlbring, Per (1)
Sunzel, Bo (1)
Nilsson, Annika (1)
Olsson, M. (1)
Hoffmann, M. (1)
Nilsson, Hans (1)
Berggren, Per-Olof (1)
Khan, Jamil (1)
Johansson, Björn (1)
Kjellgren, Karin I, ... (1)
Andersson, Per (1)
Wagner, Philippe (1)
Sydsjö, Gunilla (1)
Wickenberg, Per (1)
Rodby-Bousquet, Elis ... (1)
Ekström, Mikael (1)
Borg, K (1)
Börjesson, Pål (1)
Ahlqvist, Jan (1)
Ahlqvist, Jan, Birge ... (1)
Borg, Kennet (1)
Nilson, Hans (1)
Olsson, Morgan (1)
Norman, Patrick, Pro ... (1)
Dahlgren, S. (1)
Svenningsson, Per (1)
Johansson, Bengt (1)
Rönnerman, Karin, 19 ... (1)
Åstrand, Carolina (1)
Nilsson, Lars J (1)
Alerby, Eva (1)
Arnqvist, Anders (1)
Beach, Dennis, 1956 (1)
Nilsson, Pernilla (1)
Olin-Scheller, Chris ... (1)
Williams, Pia, 1961 (1)
Nyström, Elisabeth (1)
Andersson, Gerhard (1)
Fischer, Kerstin (1)
Gutierrez-Farewik, E ... (1)
Alriksson-Schmidt, A ... (1)
visa färre...
Lärosäte
Linköpings universitet (26)
Lunds universitet (14)
Gymnastik- och idrottshögskolan (7)
Karolinska Institutet (5)
Kungliga Tekniska Högskolan (4)
Göteborgs universitet (3)
visa fler...
Umeå universitet (3)
Uppsala universitet (1)
Stockholms universitet (1)
Mälardalens universitet (1)
Linnéuniversitetet (1)
visa färre...
Språk
Engelska (43)
Svenska (7)
Forskningsämne (UKÄ/SCB)
Medicin och hälsovetenskap (22)
Teknik (4)
Naturvetenskap (3)
Samhällsvetenskap (3)
Humaniora (1)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy