Utskrift från Malmö högskola - mah.se
Utskrift från Malmö högskola - mah.se
Now showing items 1-20 of 664
| 15 Years of Clinical Experience with Procera® Alumina | |
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Haag, Per; Andersson, M; Vult von Steyern, Per; Odén, A
Journal article in Applied Osseointegration Research (2004) |
review ARTICLE |
| English abstract: | This paper reviews the long history and background development of technical, laboratory and clinical applications of Procera® technology for the fabrication of restorations on teeth and implants. Current clinical practice is considered and long-term results presented. |
| 20-year follow-up of patients receiving high-cost dental care within ... | |
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Petersson, Kerstin; Pamenius, Madeleine; Eliasson, Alf; Narby, Birger; Holender, Frieda; Palmqvist, Sigvard; Håkansson, Jan
Journal article in Swedish dental journal;2 (2006) |
peer-reviewed
scientific ARTICLE |
| English abstract: | The objective was to perform a long-term follow-up study of patients that had received high cost dental care within the Swedish National Dental Insurance System in 1977-1978 with special focus on remaining teeth, periodontal disease progression, change in the prevalence of root-filled teeth and teeth with apical periodontitis as well as the survival of fixed prosthetic reconstructions. All 262 patients who had had their treatment plans sent for approval for high-cost dental care in 4 local health insurance districts and who were sampled for base-line studies in 1977-1978, were offered a free clinical examination including radiographs in 1998. 177 patients (68% of the original sample) could be reached for telephone interview and 104 of them (40% of the original sample) were examined clinically and radiographically. Comparisons were made with records and radiographs from 1977-1978. The analyses were performed with the individual patient as the studied unit. The low progression of severe periodontal disease during the 20-23 year follow-up period and the decrease in number of teeth with apical periodontitis among a majority of the patients examined, indicated that the dental care received resulted in a limitation of dental disease on the individual level. Furthermore 63% of the patients had the fixed prosthetic reconstructions, received after approval 1977-1978, in full extention after 20-23 years. However, more tooth losses were observed among the patients in this study than in similar studies in Swedish general populations over the same decades. Furthermore multiple tooth extractions were significantly more frequent in patients with severe periodontitis at baseline and in patients with less apical periodontitis at follow-up in this study. Thus it seems that tooth extraction not seldom was a treatment choice for teeth with severe periodontitis and apical periodontitis among the patients examined clinically in this study. |
| Accuracy and precision of a densitometric tool for jaw bone | |
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Nackaerts, Olivia; Jacobs, Reinhilde; Pillen, M; Engelen, L; Gijbels, Frieda; Devlin, Hugh; Lindh, Christina; Nicopoulou-Karayianni, Kety; van der Stelt, Paul F; Pavitt, Susan; Horner, Keith
Journal article in Dento-maxillo-facial radiology;4 (2006) |
peer-reviewed
scientific ARTICLE |
| English abstract: | OBJECTIVES: To develop a digital densitometric tool for jaw bone to analyse intraoral radiographs. To assess precision and accuracy for this tool and determine the minimal detection threshold for density changes. METHODS: Bone samples deriving from the premolar region of 47 human mandibles were selected for analysis. The samples were obtained from adult cadavers in the department of anatomy (Faculty of Medicine, KULeuven) with ethical approval. Digital radiography was performed on all bone samples. Direct volumetric measurements served as gold standard density values and allowed determination of accuracy. Dual-energy X-ray absorptiometry (DXA) scans were performed on all specimens. For all radiographs, density in mm Al eq was calculated using custom-made software, Osteop. Precision and intraobserver and interobserver reliability of this method were assessed. The bone specimens were progressively decalcified. At standard time intervals the percentage of decalcification was calculated. At each decalcification step, radiographs were taken and analysed. RESULTS: CV was always lower than 3%, which points to a good precision of the method. Correlation between the density measurements in mm Al eq and the DXA results was 0.9, for the density measurements in mm Al eq and the direct density measurements r was 0.5. The custom-made software was able to detect a change in bone mineralization of 6.6%. CONCLUSIONS: The present method for bone densitometric analysis offers potentials for clinical evaluation of bone density and minute bone density changes in the jaw bone. |
| Accuracy in osteoporosis diagnosis of a combination of mandibular cor... | |
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Karayianni, Kety; Horner, Keith; Mitsea, Anastasia; Berkas, Leonidas; Mastoris, Michael; Jacobs, Reinhilde; Lindh, Christina; van der Stelt, Paul F; Harrison, Elizabeth; Adams, Judith; Pavitt, Susan; Devlin, Hugh
Journal article in Bone;1 : Elsevier (2007) |
peer-reviewed
scientific ARTICLE |
| English abstract: | Clinical questionnaires and dental radiographic findings have both been suggested as methods of identifying women at risk of having osteoporosis and who might benefit from bone densitometry. The aim of this study was to measure the diagnostic accuracy of a combination of mandibular cortical width (MCW) measured from dental panoramic radiographs (DPRs) and the osteoporosis index of risk (OSIRIS) in the diagnosis of osteoporosis. 653 women (age range 45-70 years, mean age 54.95 years) in four European centres underwent standardised dual X-ray energy absorptiometry (DXA) to provide reference data on osteoporosis status. Each subject was interviewed to derive OSIRIS scores and underwent DPR examination. MCW was measured directly by five observers. Receiver Operating Characteristic (ROC) curve analysis was used to calculate sensitivities and specificities of the clinical and radiographic tests for the diagnosis of osteoporosis. 512 (78.4%) of the study population were classified as having normal BMD and 141 (21.6%) as having osteoporosis. Using ROC analysis, OSIRIS gave a ROC curve area (A(z)) of 0.838, with a sensitivity of 70.9% and a specificity of 79.5% at a diagnostic threshold of <or=+1. MCW on DPRs gave Az values for the five observers ranging from 0.71 to 0.78, providing sensitivities between 41.0% and 59.6% and specificities of between 81.8% and 90.3% at a diagnostic threshold of a 3 mm MCW and sensitivities between 94.2% and 99.3% and specificities of between 9.8% and 23.7% at a diagnostic threshold of a 4.5 mm MCW. Inter-observer repeatability was less than 2.15 mm for 95% of subjects. Combining clinical and radiographic tests had the effect of improving specificity at the expense of a fall in sensitivity. Diagnostic thresholds for MCW and OSIRIS can be chosen to provide the sensitivity and specificity combination that best suits locally determined needs. However, the addition of OSIRIS as a stepwise 'follow-up' test to radiographic assessment of MCW should only be performed if the aim is to have a test for which the highest achievable specificity is desired. |
| Acid Tolerance of Biofilm Cells of Streptococcus mutans | |
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Neilands, Jessica; Svensäter, Gunnel
Journal article in Applied and Environmental Microbiology;17 : American Society for Microbiology (2007) |
peer-reviewed
scientific ARTICLE |
| English abstract: | Streptococcus mutans, a member of the dental plaque community, has been shown to be involved in the carious process. Cells of S. mutans induce an acid tolerance response (ATR) when exposed to sublethal pH values that enhances their survival at a lower pH. Mature biofilm cells are more resistant to acid stress than planktonic cells. We were interested in studying the acid tolerance and ATR-inducing ability of newly adhered biofilm cells of S. mutans. All experiments were carried out using flow-cell systems, with acid tolerance tested by exposing 3-h biofilm cells to pH 3.0 for 2 h and counting the number of survivors by plating on blood agar. Acid adaptability experiments were conducted by exposing biofilm cells to pH 5.5 for 3 h and then lowering the pH to 3.5 for 30 min. The viability of the cells was assessed by staining the cells with LIVE/DEAD BacLight viability stain. Three-hour biofilm cells of three different strains of S. mutans were between 820- and 70,000-fold more acid tolerant than corresponding planktonic cells. These strains also induced an ATR that enhanced the viability at pH 3.5. The presence of fluoride (0.5 M) inhibited the induction of an ATR, with 77% fewer viable cells at pH 3.5 as a consequence. Our data suggest that adhesion to a surface is an important step in the development of acid tolerance in biofilm cells and that different strains of S. mutans possess different degrees of acid tolerance and ability to induce an ATR. |
| Activity of lactoperoxidase when adsorbed on protein layers |
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Haberska, Karolina; Svensson, Olof; Shleev, Sergey; Lindh, Liselott; Arnebrant, Thomas; Ruzgas, Tautgirdas
Journal article in Talanta;5 : Elsevier B.V. (2008) |
peer-reviewed
scientific ARTICLE |
| English abstract: | Lactoperoxidase (LPO) is an enzyme, which is used as an antimicrobial agent in a number of applications, e.g., food technology. In the majority of applications LPO is added to a homogeneous product phase or immobilised on product surface. In the latter case, however, the measurements of LPO activity are seldom reported. In this paper we have assessed LPO enzymatic activity on bare and protein modified gold surfaces by means of electrochemistry. It was found that LPO rapidly adsorbs to bare gold surfaces resulting in an amount of LPO adsorbed of 2.9 mg/m2. A lower amount of adsorbed LPO is obtained if the gold surface is exposed to bovine serum albumin, bovine or human mucin prior to LPO adsorption. The enzymatic activity of the adsorbed enzyme is in general preserved at the experimental conditions and varies only moderately when comparing bare gold and gold surface pretreated with the selected proteins. The measurement of LPO specific activity, however, indicate that it is about 1.5 times higher if LPO is adsorbed on gold surfaces containing a small amount of preadsorbed mucin in comparison to the LPO directly adsorbed on bare gold. |
Haberska08.pdf
(673.1Kb)
| Adolescents with Temporomandibular Disorder Pain - The Living with TM... | |
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Nilsson, Ing-Marie; List, Thomas; Willman, Ania
Journal article in Journal of Orofacial Pain;2 : Quintessence (2011) |
peer-reviewed
scientific ARTICLE |
| English abstract: | AIMS: To acquire a deeper understanding of adolescents' experiences of living with temporomandibular disorder (TMD) pain. METHODS: Twenty-one adolescents with TMD pain, aged 15 to 19, were strategically selected from a group of patients referred to an orofacial pain clinic. The patients were examined and received diagnoses per the Research Diagnostic Criteria for TMD. One-on-one interviews that followed a semistructured protocol focused on the patient's experiences of living with TMD pain. The interviews were recorded and transcribed verbatim, followed by content analysis to obtain a deeper understanding of adolescents' experiences living with TMD pain. RESULTS: Content analysis led to the overall theme "Adolescents with TMD live with recurrent pain; physical problems and daily demands form a vicious circle that causes adolescents to oscillate between hope and despondency." The latent content forming the theme is grounded in three categories that evolved from 13 subcategories. For instance, five subcategories-headache; headache on awakening; jaw and tooth pain; constant thoughts of pain; and popping, cracking, clicking, and locking-formed the category that was labeled TMD pain is recurrent. The latent interpretation, ie, the meaning, of this category was that adolescents with TMD pain constantly thought about the pain, even when it was absent. CONCLUSION: TMD pain is a substantial problem for affected adolescents and has consequences for all aspects of their lives. In this study, the adolescents were able to talk openly and introduce issues outside of the interview protocol. Qualitative analysis deepens our understanding of the adolescent patient with TMD pain. |
| Adsorption behaviour and surfactant elution of cationic salivary prot... |
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Svendsen, Ida; Lindh, Liselott; Arnebrant, Thomas
Journal article in Colloids and Surfaces B: Biointerfaces;2 : Elsevier (2006) |
peer-reviewed
scientific ARTICLE |
| English abstract: | Adsorption of the cationic salivary proteins lactoferrin, lactoperoxidase, lysozyme and histatin 5 to pure (hydrophilic) and methylated (hydrophobized) silica surfaces was investigated by in situ ellipsometry. Effects of concentration (≤10 μg ml−1, for lysozyme ≤200 μg ml−1) and dependence of surface wettability, as well as adsorption kinetics and elutability of adsorbed films by buffer and sodium dodecyl sulphate (SDS) solutions were investigated. Results showed that the amounts adsorbed decreased in the order lactoferrin ≥ lactoperoxidase > lysozyme ≥ histatin 5. On hydrophilic silica, the adsorption was most likely driven by electrostatic interactions, which resulted in adsorbed amounts of lactoferrin that indicated the formation of a monolayer with both side-on and end-on adsorbed molecules. For lactoperoxidase the adsorbed amounts were somewhat higher than an end-on monolayer, lysozyme adsorption showed amounts corresponding to a side-on monolayer, and histatin 5 displayed adsorbed amounts in the range of a side-on monolayer. On hydrophobized substrata, the adsorption was also mediated by hydrophobic interactions, which resulted in lower adsorbed amounts of lactoferrin and lactoperoxidase; closer to side-on monolayer coverage. For both lysozyme and histatin 5 the adsorbed amounts were the same as on the hydrophilic silica. The investigated proteins exhibited fast adsorption kinetics, and the initial kinetics indicated mass transport controlled behaviour at low concentrations on both types of substrates. Buffer rinsing and SDS elution indicated that the proteins in general were more tightly bound to the hydrophobized surface compared to hydrophilic silica. Overall, the surface activity of the investigated proteins implicates their importance in the salivary film formation. |
sdarticle.pdf
(461.2Kb)
| Adsorption behaviour of statherin and a statherin peptide onto hydrox... | |
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Santos, Olga; Kosoric, Jelena; Hector, Mark P; Anderson, Paul; Lindh, Liselott
Journal article in Journal of colloid and interface science;2 (2008) |
peer-reviewed
scientific ARTICLE |
| English abstract: | The salivary protein statherin is known to adsorb selectively onto hydroxyapatite (HA), which constitutes the main mineral of the tooth enamel. This adsorption is believed to be crucial for its function as an inhibitor of primary (spontaneous) and secondary (crystal growth) precipitation of calcium phosphate salts present in saliva. A fragment corresponding to the first 21 N-terminus amino acids of statherin (StN21) was previously found to reduce the rate of demineralization of HA. Therefore, the interfacial properties of this peptide and statherin onto silica, hydrophobized silica and HA discs was studied by in situ ellipsometry. Their reversibility induced by dilution and elutability induced by buffer and sodium dodecyl sulfate (SDS) was also determined. The results revealed that statherin adsorbed at a greater extent onto the HA as compared to StN21, suggesting that the hydrogen bonding between the uncharged polar residues at the C-terminal region of statherin and HA contributes to its adsorption. However, on both silica surfaces the peptide adsorption appeared to proceed in a similar way. Onto the hydrophobized silica the adsorption of both peptides was suggested to occur either via multilayer formation or adsorption of aggregates from solution, while onto the hydrophilic silica adsorption of peptide aggregates from solution was the suggested mechanism. Further, both peptides were observed to be strongly adsorbed onto HA, even after SDS treatment, in comparison to the layers adsorbed onto hydrophobized silica. Both peptide layers were found to be weakly adsorbed onto the hydrophilic silica surface as they were totally removed by buffer dilution. |
| Adsorption from saliva to silica and hydroxyapatite surfaces and elut... | |
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Santos, Olga; Lindh, Liselott; Halthur, Tobias; Arnebrant, Thomas
Journal article in Biofouling;6 (2010) |
peer-reviewed
scientific ARTICLE |
| English abstract: | The adsorption of human whole saliva (HWS) onto silica and hydroxyapatite surfaces (HA) was followed by quartz crystal microbalance with dissipation (QCM-D) and ellipsometry. The influence of different surface properties and adsorption media (water and PBS) on the HWS adsorption was studied. The viscoelastic properties of the saliva films formed onto the solid surfaces were estimated by the use of the Voigt-based viscoelastic film model. Furthermore, the efficiency of SDS and delmopinol to elute the adsorbed saliva film from the surfaces was investigated at different surfactant concentrations. It was observed a biphasic kinetic regime for the adsorption of saliva on the silica and HA surfaces, indicating the formation of a rigidly coupled first layer corresponding to an initial adsorption of small proteins and a more loosely bound second layer. The results further showed a higher adsorption of HWS onto the HA surfaces compared to the silica surfaces in both adsorption media (PBS and water). The adsorption in PBS led to higher adsorbed amounts on both surfaces as compared to water. SDS was found to be more efficient in removing the saliva film from both surfaces than delmopinol. The salivary film was found to be less tightly bound on to the silica surfaces since more saliva film could be removed with both SDS and delmopinol compared to from the HA surface. When saliva was adsorbed from PBS a higher energy dissipation was determined implying that a softer saliva layer is build up in PBS as opposed to in water. In the same media (water) a softer saliva layer was formed onto the HA surfaces, while in PBS the saliva layer formed at both surfaces seems to have similar structure. |
| Adsorption of HSA, IgG and laminin-1 on model hydroxyapatite surfaces... |
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Svendsen, Ida; Santos, Olga; Sotres, Javier; Wennerberg, Ann; Breding, Karin; Arnebrant, Thomas; Lindh, Liselott
Journal article in Biofouling : The Journal of Bioadhesion and Biofilm Research;1 : Taylor & Francis Group (2012) |
peer-reviewed
scientific ARTICLE |
| English abstract: | Ellipsometry and mechanically assisted sodium dodecyl sulphate elution was utilized to study the adsorption of human serum albumin (HSA), human immunoglobulin G (IgG), and laminin-1, as well as competitive adsorption from a mixture of these proteins on spin-coated and sintered hydroxyapatite (HA) surfaces, respectively. The HA surfaces were characterized with respect to wettability and roughness by means of water contact angles and atomic force microscopy, respectively. Both surface types were hydrophilic, and the average roughness (Sa) and surface enlargement (Sdr) were lower for the sintered compared to the spin-coated HA surfaces. The adsorbed amounts on the sintered HA increased as follows: HSA < laminin-1 < IgG < the protein mixture. For the competitive adsorption experiments, the adsorbed fractions increased accordingly: HSA < laminin-1 < IgG on both types of HA substratum. However, a higher relative amount of HSA and laminin-1 and a lower relative amount of IgG was found on the spin-coated surfaces compared to the sintered surfaces. The effects observed could be ascribed to differences in surface roughness and chemical composition between the two types of HA substratum, and could have an influence on selection of future implant surface coatings. |
manuscript_Svendsen_et_al_111027.pdf
(1.496Mb)
| Adsorption of HSA, IgG and laminin-1 on model titania surfaces – effe... | |
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Santos, Olga; Svendsen, Ida E; Lindh, Liselott; Arnebrant, Thomas
Journal article in Biofouling;9 : Taylor & Francis (2011) |
peer-reviewed
scientific ARTICLE |
| English abstract: | This study investigated the effect of glow discharge treatment of titania surfaces on plasma protein adsorption, by means of ellipsometry and mechanically assisted SDS elution. The adsorption and film elution of three plasma proteins, viz. human serum albumin (HSA), human immunoglobulin G (IgG) and laminin-1, as well as competitive adsorption from a mixture of the three proteins, showed that the adsorbed amount of the individual proteins after 1 h increased in the order HSA <IgG <laminin-1 ≤ protein mixture. Film elutability showed that 30 min of SDS interaction resulted in almost complete removal of adsorbed films. No difference in the total adsorbed amounts of individual proteins, or from the mixture, was observed between untreated and glow discharge treated titania surfaces. However, the composition of the adsorbed films from the mixture differed between the untreated and glow discharge treated substrata. On glow discharge-treated titania the fraction of HSA increased, the fraction of laminin-1 decreased and the fraction of IgG was unchanged compared to the adsorption on the untreated titania, which was attributed to protein-protein interactions and competitive/associative adsorption behaviour. |
| Adsorption of MUC5B and the role of mucins in early salivary film for... | |
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Lindh, Liselott; Glantz, Per-Olof; Carlstedt, Ingemar; Wickström, Claes; Arnebrant, Thomas
Journal article in Colloids and Surfaces B: Biointerfaces;2 : Elsevier (2002) |
peer-reviewed
scientific ARTICLE |
| English abstract: | Salivary mucins are known to play important roles in the formation of oral salivary films. The aims of the present study were to investigate the behaviour of salivary mucins at solid surfaces with different wettabilities, as well as the influence of electrolyte on the adsorption behaviour. A pure preparation of human salivary MUC5B was used together with a commercial one of bovine submaxillary mucin (BSM). Amounts adsorbed from freshly prepared solutions onto hydrophilic and hydrophobic surfaces versus time were measured in situ by ellipsometry. At low concentrations, larger amounts were adsorbed onto hydrophobic than onto hydrophilic silica indicating a higher affinity for the former surfaces. Furthermore, on hydrophilic surfaces adsorbed amounts of MUC5B and BSM show good agreement at low concentrations (<0.10 mgml^-^1). However, at higher concentrations MUC5B adsorbed to a lower extent than BSM. At hydrophobic surfaces, isotherm shapes were similar for the two preparations, but the amounts were shifted to higher values for MUC5B. Finally, the presence of electrolyte increased adsorption and the increase was more pronounced on hydrophilic surfaces. The increased adsorption at a higher ionic strength indicates a more compact structure of the mucin due to electrostatic screening and the fact that the effect was more pronounced on the hydrophilic surfaces points to a higher relative importance of electrostatic interactions in this case. We conclude that the two mucins investigated behave in a qualitatively similar manner and show the highest affinity for hydrophobic surfaces. |
| Adsorption of the Flexible Salivary Proteins Statherin and PRP-1 to N... | |
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Skepö, Marie; Lindh, Liselott; Arnebrant, Thomas
Journal article in Zeitschrift für Physikalische Chemie;1 : Oldenbourg Wissenschaftsverlag, München (2007) |
peer-reviewed
scientific ARTICLE |
| English abstract: | The structural properties of the salivary proteins, acidic proline rich PRP-1 and statherin, adsorbed onto negatively charged surfaces have been studied by Monte Carlo simulations and ellipsometry. It is shown that both proteins adsorb to negatively charged surfaces, although their net charges are negative. Experimentally, an initial fast mass-controlled film build-up was detected for both proteins, and plateaus were reached within 10 minutes. The isotherm shape and the adsorbed amounts were similar for PRP-1 to hydrophilic and hydrophobic surfaces, while statherin adsorbs to a greater extent to the hydrophobic surface. These results could be explained from the simulation results by considering the proteins as diblock polyampholytes. It has also been shown that the adsorption of PRP-1 to a negatively charged surface may be purely electrostatically driven, while pure electrostatic interaction is not sufficient to drive adsorption of statherin, i.e., an extra short-ranged attractive interaction is necessary to account for the experimental observations. |
| Akademisk kvalitet, vad är det? : Om utarmningen av den akademiska au... | |
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Droppe, Adam; Söderfeldt, Björn
Journal article in Sociologisk Forskning;3 (2010) |
scientific ARTICLE |
| English abstract: | What is Academic Quality? On the Decline of Academic Autonomy In light of the transformations that universities currently undergo, with Bologna as a keyword, the following questions are put: What ideals lie behind the assessment of academic “excellence” and “quality”? Who are the agents having the ability to define what is good science and education today? These questions are approached through Pierre Bourdieu’s concept of field. Looking at the development during the last decade, traditional academic values, such as the ideals of universal knowledge as (personal and collective) enrichment and of intellectual independence “of all political authority and economic power”, as stated in the Magna Charta Universitatum, seem to have been pushed into the shadow of employability, knowledge control, competitiveness, and economic benefit. In connection with the formation of concepts such as “the knowledge society” and “knowledge based economies” the university has received a somewhat different and more central role in society. The university has come to take the role more of a knowledge producing enterprise clearly directed towards the surrounding society. There are higher demands on academic knowledge to contribute to economic, regional or national development and competitiveness. When the university is regarded as a knowledge company whose task is to account for the requests of the students, the labour market, and the business world it undertakes to follow trends and short term social trends rather than to critically examine them, which has been a traditional task for the university. If the academic work is guided by the market economy principle, that clients decide what quality is, instead of experts on the academic field (i.e. the scientists,) it is obviously not scientific ideals that constitute the criteria for what is good science and education. |
| Allt är inte tandvärk - långvarig smärta i ansikte och käkar. | |
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List, Thomas; Axelsson, Susanna
Journal article in Primärvårdens nyheter;1-2 (2007) |
ARTICLE |
| All-ceramic Fixed Partial Dentures Designed According to the DC-Zirko... | |
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Vult von Steyern, Per; Carlsson, P; Nilner, Krister
Journal article in Journal of Oral Rehabilitation;3 : Blackwell Publishing (2005) |
peer-reviewed
scientific ARTICLE |
| English abstract: | The aim of the present in-vitro study was to compare the fracture strength of all-ceramic Fixed Partial Dentures supported by tooth-analogues and periodontal membrane with the same supported by dental implants. As ceramics are highly brittle, they cannot withstand deformations of more than 0.1% without fracturing. Hence, when planning an all-ceramic FPD, it is essential to evaluate abutment sup-port, as the fracture strength of all-ceramic constructions depends on the stability of the support to reduce strain in the beam of the prosthe-sis. The support provided by implants differs, however, from the sup-port provided by natural teeth as the implants are anchored directly in the bone with no intermediate tissue. One question that arises is whether strain and stress in the prosthesis are lower when the prosthe-sis is loaded on implants compared to natural teeth and hence if all-ceramic FPDs benefit from implant support. Twenty-four three-unit all-ceramic FPDs-12 supported by two dental implants and 12 by two tooth-analogues serving as end abutments-were made. All FPDs were subjected to preloading in a preloading procedure and subsequently subjected to load until fracture occurred. Load at fracture were regis-tered and comparisons between the two groups were made. The loads at fracture were statistically significant higher in the group supported by implants compared to the group supported by tooth-analogues (p = 0.003). Within the limitations of this in-vitro study, the following con-clusions can be drawn: All-ceramic fixed partial dentures can be used in combination with dental implants. The solid support gained from implants might thus be beneficial for the outcome of such treatment due to decreased strain and stress levels in the prosthesis when loaded on implants compared to when loaded on natural teeth. Clinical stud-ies are, however, needed to confirm these findings as there are more factors that influence the final clinical outcome. |
| All-ceramic two- to five-unit implant-supported reconstructions. A ra... | |
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Larsson, Christel; Vult von Steyern, Per; Sunzel, Bo; Nilner, Krister
Journal article in Swedish dental journal;2 (2006) |
peer-reviewed
scientific ARTICLE |
| English abstract: | The purpose of this study was to evaluate the clinical performance of two to five-unit implant-supported all-ceramic reconstructions and to compare the results of two different all-ceramic systems, Denzir (DZ) and In-Ceram Zirconia (InZ). Eighteen patients were treated with a total of 25 two- to five-unit implant-supported reconstructions. Nine patients were given reconstructions of the DZ system and the other nine reconstructions of the InZ system.The reconstructions were cemented with zinc phosphate cement onto preparable titanium abutments and were evaluated after 6 and 12 months. At the 12-month follow-up, all reconstructions were in function; none had fractured. Superficial cohesive (chip-off) fractures were, however, observed in 6 of the 18 patients (8 of 25 reconstructions). Nine units in the DZ group (in 7 of 13 reconstructions) and one in the InZ group (1 of 12 reconstructions) had chip-off fractures. The difference between the two groups regarding frequency of chip-off fractures was statistically significant (P < 0.01). Marginal integrity was rated excellent at 34 abutments (56%) and acceptable at 27 (44%). Results from this 12-month trial suggest that all-ceramic implant-supported fixed partial dentures of two- to five-units may be considered a treatment alternative. When comparing the two ceramic systems under study, however, this study concludes that the DZ system exhibits an unacceptable amount of veneering porcelain fractures and thus cannot be recommended for the type of treatment evaluated in this trial. Further studies and long-term follow-ups must be performed before the materials and technique can be recommended for general use. |
| Alpha-1 antitrypsin deficiency and periodontitis, a pilot study | |
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Wallin Bengtsson, Viveca; Piitulainen, Eeva; Hamberg, Christina; Lindh, Christina; Bratthall, Gunilla
Journal article in Swedish Dental Journal;1 (2011) |
peer-reviewed
scientific ARTICLE |
| English abstract: | The aim of this study was to investigate if periodontal parameters and elastase in gingival crevicular fluid (GCF) are different in alpha-1-antitrypsin deficient (AATD) subjects compared to subjects with normal AAT level. Thirty subjects were included, 20 of whom with severe AATD, phenotype PiZZ. Ten AATD subjects suffered from chronic obstructive pulmonary disease (COPD, group 1) and 10 were asymptomatic (group 2). Ten control subjects, phenotype PiMM, (group 3) were recruited from a public dental clinic. The examination comprised of sampling of GCF, Gingival Index (GI), Plaque Index (PlI), probing pocket depth (PPD) and radiography. GCF was collected with paper strips (Periopaper®). Plasma AAT concentration was measured by nephelometry and AAT in GCF with ELISA. Elastase activity and protein in GCF were determined by spectrophotometry. The mean values for GI, PlI, PPD and the radiological measurements did not show any statistically significant differences between the groups. AAT in plasma and GCF demonstrated very low values in groups 1 and 2 with no significant difference between these groups but a statistical difference in comparison with group 3. Elastase in GCF did not show any difference between the three groups. In conclusion, neither the periodontal parameters nor the elastase in GCF were different in AATD subjects, phenotype PiZZ, when compared to subjects with normal AAT level, phenotype PiMM, in this material. |
| Swedish abstract: | Målet med studien var att undersöka om parodontala parametrar och elastas i gingivalvätska (GCF) skilde sig hos individer med alfa-1-antrypsin-brist (AAT-brist) jämfört med individer med normal AAT-halt. I studien ingick 30 individer, varav 20 med allvarlig AAT-brist, fenotyp PiZZ. Tio individer med AAT- brist led av kronisk obstruktiv lungsjukdom (KOL) (grupp 1) och 10 var symptomfria (grupp 2). Tio individer med normal AAT-halt, fenotyp PiMM (grupp 3), utgjorde kontrollgrupp och rekryterades från en allmäntandvårdsklinik. Undersökningen bestod av insamling av GCF, gingivalindex (GI), plackindex (PlI), fickdjupsmätning (PPD) och röntgen. GCF samlades in med hjälp av pappers-strips (Periopaper®). AAT i plasma mättes med nefelometri och AAT i GCF mättes med ELISA. Elastasaktivitet och proteinmängd i GCF bestämdes med spektrofotometri. Medelvärden för GI, PlI, PPD och röntgenmätningar visade inga statistiskt signifikanta skillnader mellan grupperna. AAT i plasma och GCF visade mycket låga värden i grupp 1 och 2 utan några signifikanta skillnader mellan grupperna men en signifikant skillnad i jämförelse med grupp 3. Elastas i gingivalvätska visade inga skillnader mellan de tre grupperna. Sammanfattningsvis visade varken parodontala värden eller elastas i GCF några skillnader hos individer med AAT- brist, fenotyp PiZZ, jämfört med individer med normal AAT-halt, fenotyp PiMM, i detta material. |
| Alterations of temporomandibular disorders before and after orthognat... | |
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Abrahamsson, Cecilia; Ekberg, EwaCarin; Henrikson, Thor; Bondemark, Lars
Journal article in 4 : Angle Orthodontist (2007) |
review ARTICLE |
| English abstract: | OBJECTIVE: To answer the question whether orthognathic surgery does affect the prevalence of signs and symptoms of temporomandibular disorders (TMDs). MATERIALS AND METHODS: A literature survey in the PubMed and Cochrane Library electronic databases was performed and covered the period from January 1966 to April 2006. The inclusion criteria were controlled, prospective or retrospective studies comparing TMDs before and after orthognathic surgery in patients with malocclusion. There were no language restrictions, and three reviewers selected and extracted the data independently. The quality of the retrieved articles was evaluated by four reviewers. RESULTS: The search strategy resulted in 467 articles, of which 3 met the inclusion criteria. Because of few studies with unambiguous results and heterogeneity in study design, the scientific evidence was insufficient to evaluate the effects that orthognathic surgery had on TMD. Moreover, the studies had problems with inadequate selection description, confounding factors, and lack of method error analysis. CONCLUSION: To obtain reliable scientific evidence, additional well-controlled and well-designed studies are needed to determine how and if orthognathic surgery alters signs and symptoms of TMD. |
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