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- Arvidsson, Anna, 1973, et al.
(författare)
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Characterisation of structures in salivary secretion film formation. An experimental study with atomic force microscopy
- 2004
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Ingår i: Biofouling. - : Informa UK Limited. - 0892-7014 .- 1029-2454. ; 20:3, s. 181-8
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the present study was to characterise the structure dynamics of pure salivary secretions retained on controlled surfaces with different surface energies in the early stage of salivary film formation. Germanium prisms prepared to have either low surface energy or medium surface energy were incubated in fresh secretions of either human parotid saliva (HPS) or human submandibular/sublingual saliva (HSMSLS) for 15, 90, and 180 min. After controlled rinsing with distilled water, the surfaces were air dried and thereafter imaged with atomic force microscopy (AFM). The amount of adsorbed material and the size of the structures detected increased with increased saliva exposure time. The film thicknesses varied from 10 to 150 nm, and both HPS and HSMSLS films contained structures with diameters varying from 40 nm to 2 microm. Some of these were clustered into special formations. The HPS films exhibited a more granular morphology than the HSMSLS films. Furthermore, branched lines were detected on the low surface energy germanium prisms incubated in saliva. The results indicate that exposure time, surface energy, and type of salivary secretion all are factors affecting the adsorption characteristics of salivary films.
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| 2. |
- Arvidsson, Anna, 1973, et al.
(författare)
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Formation of calcium phosphates on titanium implants with four different bioactive surface preparations. An in vitro study
- 2007
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Ingår i: Journal of Materials Science-Materials in Medicine. - : Springer Science and Business Media LLC. - 0957-4530 .- 1573-4838. ; 18:10, s. 1945-1954
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to compare the nucleating and growing behaviour on four types of bioactive surfaces by using the simulated body fluid (SBF) model. Titanium discs were blasted and then prepared by alkali and heat treatment, anodic oxidation, fluoridation, or hydroxyapatite coating. The discs were immersed in SBF for 1, 2, 4 and 6 weeks. Calcium phosphates were found on all specimens, as analysed with scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDX). After 1 and 2 weeks of SBF immersion more titanium was accessible with SEM/EDX on the blasted surfaces than the four bioactive surface types, indicating a difference in coverage by calcium phosphates. The Ca/P mean ratio of the surfaces was approximately 1.5 after 1 week, in contrast to the fluoridated specimens which displayed a Ca/P mean ratio of approximately 2. Powder X-ray diffraction (P-XRD) analyses showed the presence of hydroxyapatite on all types of surfaces after 4 and 6 weeks of immersion. The samples immersed for 6 weeks showed a higher degree of crystallinity than the samples immersed for 4 weeks. In conclusion, differences appeared at the early SBF immersion times of 1 and 2 weeks between controls and bioactive surface types, as well as between different bioactive surface types.
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| 3. |
- Arvidsson, Anna, 1973, et al.
(författare)
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Influence of chemo-mechanical caries removal on the surface topography of dental composite resin and glass-ionomer materials: an in vitro study
- 2004
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Ingår i: Acta Odontologica Scandinavica. ; 62:3, s. 137-142
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to investigate the influence of a chemo-mechanical caries removal system, Carisolv gel, on the surface topography of dental filling materials. Thirty specimens of a composite resin (Spectrum) and a compomer (Dyract AP) and 60 specimens of a glass-ionomer (Ketac-Fil Plus) were prepared. The surface topography was investigated with an optical interferometer before and after chemical exposure for 5, 10, or 20 min. Each specimen acted as its own control. The topographical part of the glass-ionomer materials was performed in two series with different drying procedures, since this material exhibits a higher sensitivity to dehydration than the other materials. The surface topographical investigations were complemented with contact angle measurements. After Carisolv gel exposure the density of summits and the developed surface area ratio (3D/2D) were slightly smaller for the composite resin and the compomer. For the minimally dried glass-ionomer material, the results indicated a reduction of the height of the surface structures, as well as a surface area enlargement, after Carisolv gel exposure. No statistically significant changes of contact angles due to Carisolv gel exposure could be detected for any material investigated. If dental filling materials of composite resin or glass-ionomer materials are exposed to Carisolv gel, no or only minor surface topographical changes can be expected.
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| 4. |
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| 5. |
- Arvidsson, Anna, 1973, et al.
(författare)
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The role of functional parameters for topographical characterization of bone-anchored implants
- 2006
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Ingår i: Clin Implant Dent Relat Res. ; 8:2, s. 70-6
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The surface topographical characterization of bone-anchored implants has been recommended to be based on amplitude, spatial, and hybrid parameters. There are also functional parameters that have the potential to describe characteristics important for a specific application. PURPOSE: The aim of the present study was to evaluate if parameters that have been described as functional in engineering applications are also relevant in the topographical characterization of bone-anchored implants. MATERIALS AND METHODS: The surface topography of threaded titanium implants with different surface roughness (S(a), S(ds), and S(dr)) was analyzed with an optical interferometer, and five candidating functional parameters (S(bi), S(ci), S(vi), S(m), and S(c)) were calculated. Examples of the same parameters for five commercially available dental implants were also calculated. Results The highest core fluid retention index (S(ci)) was displayed by the turned implants, followed by fixtures blasted with 250- and 25-microm particles, respectively. Fixtures blasted with 75-microm Al(2)O(3) particles displayed the lowest S(ci) value. This is the inverse order of the bone biological ranking based on earlier in vivo studies with the experimental surfaces included in the present study. CONCLUSION: A low core fluid retention index (S(ci)) seems favorable for bone-anchored implants. Therefore, it is suggested to include S(ci) to the set of topographical parameters for bone-anchored implants to possibly predict the biological outcome.
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| 6. |
- Franke Stenport, Victoria, 1970, et al.
(författare)
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Precipitation of calcium phosphate in the presence of albumin on titanium implants with four different possibly bioactive surface preparations. An in vitro study
- 2008
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Ingår i: Journal of Materials Science: Materials in Medicine. - : Springer Science and Business Media LLC. - 0957-4530 .- 1573-4838. ; 19:12, s. 3497-3505
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to compare the nucleating behaviour on four types of bioactive surfaces by using the simulated body fluid (SBF) model with the presence albumin. Titanium discs were blasted (B) and then prepared by alkali and heat treatment (AH), anodic oxidation (AO), fluoridation (F), or hydroxyapatite coating (HA). The discs were immersed in SBF with 4.5 mg/ml albumin for 3 days, 1, 2, 3 and 4 weeks and analysed with scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDX) and X-ray photoelectron spectroscopy (XPS). Topographic surface characterisation was performed with a contact stylus profilometer. The results demonstrated that the bioactive surfaces initiated an enhanced calcium phosphate (CaP) formation and a more rapid increase of protein content was present on the bioactive surfaces compared to the blasted control surface. The observation was present on all bioactive surfaces. The fact that there was a difference between the bioactive surfaces and the blasted control surface with respect to precipitation of CaP and protein content on the surfaces support the fact that there may be biochemical advantages in vivo by using a bioactive surface.
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| 7. |
- Göransson, Anna, 1970, et al.
(författare)
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An in vitro comparison of possibly bioactive titanium implant surfaces.
- 2009
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Ingår i: Journal of Biomedical Materials Research Part A. - : Wiley. - 1552-4965 .- 1549-3296. ; 88:4, s. 1037-1047
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the study was to compare Ca and P formation (CaP) and subsequent bone cell response of a blasted and four different possibly bioactive commercially pure (cp) titanium surfaces; 1. Fluoride etched (Fluoride), 2. Alkali-heat treated (AH), 3. Magnesium ion incorporated anodized (TiMgO), and 4. Nano HA coated and heat treated (nano HA) in vitro. Furthermore, to evaluate the significance of the SBF formed CaP coat on bone cell response. The surfaces were characterized by Optical Interferometry, Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS). CaP formation was evaluated after 12, 24 and 72 h in simulated body fluid (SBF). Primary human mandibular osteoblast-like cells were cultured on the various surfaces subjected to SBF for 72 h. Cellular attachment, differentiation (osteocalcin) and protein production (TGF-beta(1)) was evaluated after 3 h and 10 days respectively. Despite different morphological appearances, the roughness of the differently modified surfaces was similar. The possibly bioactive surfaces gave rise to an earlier CaP formation than the blasted surface, however, after 72 h the blasted surface demonstrated increased CaP formation compared to the possibly bioactive surfaces. Subsequent bone cell attachment was correlated to neither surface roughness nor the amount of formed CaP after SBF treatment. In contrast, osteocalcin and TGF-beta(1) production were largely correlated to the amount of CaP formed on the surfaces. However, bone response (cell attachment, osteocalcin and TGF-F production) on the blasted controls were similar or increased compared to the SBF treated fluoridated, AH and TiMgO surface. (c) 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008.
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| 8. |
- Meirelles, Luiz, 1974, et al.
(författare)
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Bone reaction to nano hydroxyapatite modified titanium implants placed in a gap-healing model
- 2008
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Ingår i: Journal Biomedical MAterials Research - A. - : Wiley. - 1549-3296 .- 1552-4965. ; 87:3, s. 624-631
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Tidskriftsartikel (refereegranskat)abstract
- Nanohydroxyapatite materials show similar chemistry to the bone apatite and depending on the underlying topography and the method of preparation, the nanohydroxyapatite may simulate the specific arrangement of the crystals in bone. Hydroxyapatite (HA) and other CaP materials have been indicated in cases in which the optimal surgical fit is not achievable during surgery, and the HA surface properties may enhance bone filling of the defect area. In this study, very smooth electropolished titanium implants were used as substrata for nano-HA surface modification and as control. One of each implant (control and nano HA) was placed in the rabbit tibia in a surgical site 0.7 mm wider than the implant diameter, resulting in a gap of 0.35 mm on each implant side. Implant stability was ensured by a fixating plate fastened with two side screws. Topographical evaluation performed with an optical interferometer revealed the absence of microstructures on both implants and higher resolution evaluation with AFM showed similar nanoroughness parameters. Surface pores detected on the AFM measurements had similar diameter, depth, and surface porosity (%). Histological evaluation demonstrated similar bone formation for the nano HA and electropolished implants after 4 weeks of healing. These results do not support that nano-HA chemistry and nanotopography will enhance bone formation when placed in a gap-healing model. The very smooth surface may have prevented optimal activity of the material and future studies may evaluate the synergic effects of the surface chemistry, micro, and nanotopography, establishing the optimal parameters for each of them.
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