| 1. |
- Ellingsen, Jan Eirik, et al.
(författare)
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Improved retention and bone-tolmplant contact with fluoride-modified titanium implants.
- 2004
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Ingår i: International Journal of Oral & Maxillofacial Implants. - 0882-2786. ; 19:5, s. 659-66
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The purpose of the present study was to investigate whether a fluoride modification of the titanium surface would have an effect on bone response after implantation. MATERIALS AND METHODS: Titanium-oxide-blasted titanium implants with and without fluoride modification were investigated in a rabbit tibia model. Quantitative analysis of surface roughness, biomechanical interlocking, and in vivo tissue reactions in rabbit bone at 1 and 3 months after placement were compared. RESULTS: The fluoride-modified test implants had a slightly smoother surface (Sa: 0.91 +/- 0.14 microm) than the unmodified control implants (Sa: 1.12 +/- 0.24 microm). Significantly higher removal torque values (85 +/- 16 Ncm vs 54 +/- 12 Ncm) and shear strength between bone and implants (23 +/- 9 N/mm2 vs 15 +/- 5 N/mm2) were measured for the fluoride-modified implants after 3 months. The histomorphometric evaluations demonstrated higher bone-to-implant contact for test implants at 1 month (35% +/- 14% vs 26% +/- 8%) and 3 months (39% +/- 11% vs 31% +/- 6%) after placement. DISCUSSION: Implant surface modification with fluoride may result in morphologic and physiochemical phenomena that are of significance for the bone response. Another possible explanation for the findings in the present study is that a surface modification changes the surface chemical structures to be more suitable for bone bonding. CONCLUSION: Based on the biomechanical and histomorphometric data, the fluoride-modified titanium implants demonstrated a firmer bone anchorage than the unmodified titanium implants. These implants achieved greater bone integration than unmodified titanium implants after a shorter healing time.
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| 2. |
- Wennerberg, Ann, 1955, et al.
(författare)
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Titanium release from implants prepared with different surface roughness
- 2004
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Ingår i: Clin Oral Implants Res. ; 15:5, s. 505-12
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: There may be a risk of greater ion release for surface-enlarged implants than conventionally turned components. The major aim of the present paper was to investigate whether a correlation exists between ion release and a surface roughness relevant for today's commercial implants. Other aims were to compare ion release after two insertion times and concentration in bone tissue as a function of distance from the implant surface. MATERIAL AND METHODS: Lactic acid aqueous solution (pH=2.3) and phosphate-buffered saline were used for the in vitro investigation. For the in vivo investigation, synchrotron radiation X-ray fluorescence (SRXRF) spectroscopy and secondary ion mass spectroscopy (SIMS) were performed 12 weeks and 1 year after implantation in rabbit tibiae. RESULTS: The average height deviation (S(a)) was 0.7, 1.27, 1.43 and 2.21 microm, respectively, for the four surfaces investigated. No difference in ion release was found in vitro. In vivo, SRXRF demonstrated slightly higher values for the roughest surface up to a distance of 400 microm from the implant surface; thereafter no difference was found. SIMS demonstrated no difference in ion release for the roughest and smoothest surfaces, but slightly more titanium in bone tissue after 1 year than after 12 weeks. Titanium rapidly decreased with distance from the implant surface. CONCLUSION: At a level relevant for commercial oral implants, no correlation was found between increasing roughness and ion release, neither in vitro nor in vivo.
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| 3. |
- Albrektsson, Tomas, 1945, et al.
(författare)
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Oral implant surfaces: Part 1--review focusing on topographic and chemical properties of different surfaces and in vivo responses to them
- 2004
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Ingår i: Int J Prosthodont. ; 17:5, s. 536-43
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: This article reviews the topographic and chemical properties of different oral implant surfaces and in vivo responses to them. MATERIALS AND METHODS: The article considers detailed mechanical, topographic, and physical characteristics of implant surfaces. Anchorage mechanisms such as biomechanical and biochemical bonding are examined. Osteoattraction and doped surfaces are discussed. RESULTS: Surface quality of an oral implant may be subdivided into mechanical, topographic, and physicochemical properties. Topographic properties are evaluated at the micrometer level of resolution. Moderately rough surfaces (Sa between 1.0 and 2.0 microm) show stronger bone responses than smoother or rougher surfaces. The majority of currently marketed implants are moderately rough. Oral implants permit bone ingrowth into minor surface irregularities-biomechanical bonding or osseointegration. Additional biochemical bonding seems possible with certain surfaces. Osteoattraction is a commercial term without precise biologic correspondence. Surfaces doped with biochemical agents such as bone growth factors have been developed. CONCLUSION: Moderately roughened surfaces seem to have some clinical advantages over smoother or rougher surfaces, but the differences are small and often not statistically significant. Bioactive implants may offer some promise.
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| 4. |
- Albrektsson, Tomas, 1945, et al.
(författare)
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Oral implant surfaces: Part 2--review focusing on clinical knowledge of different surfaces
- 2004
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Ingår i: Int J Prosthodont. ; 17:5, s. 544-64
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: This article reviews clinical knowledge of selected oral implant surfaces. MATERIALS AND METHODS: The surfaces most commonly used in clinical practice, marketed by the five largest oral implant companies, are identified; their clinical documentation was scrutinized following a strict protocol. Experimental knowledge of the surfaces is briefly summarized. Retrospective, prospective, and comparative clinical studies were analyzed separately, as were studies of implants in conjunction with bone grafts. RESULTS: TiUnite anodized surfaces are clinically documented in 1- to 2-year follow-up studies at best, with failures at about 3%. Sandblasted and acid-etched SLA surfaces are documented with good clinical results for up to 3 years. Osseotite dual acid-etched implants are documented with good clinical results for up to 5 years. Frialit-2 sandblasted and etched implants are positively documented for about 3 years in one study only. The Tioblast implant is the only design documented for survival over 10 years of follow-up and success over 7 years of follow-up. CONCLUSION: Generally, oral implants are introduced clinically without adequate clinical documentation. Implant companies initiate clinical documentation after product launch. The standards of clinical reporting have improved over the years. Proper long-term reports have been published for only one surface, Tioblast.
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| 5. |
- 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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| 6. |
- 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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| 7. |
- Macdonald, Warren, 1954, et al.
(författare)
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Variation in surface texture measurements.
- 2004
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Ingår i: Journal of biomedical materials research. Part B, Applied biomaterials. - : Wiley. - 1552-4973. ; 70:2, s. 262-9
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Tidskriftsartikel (refereegranskat)abstract
- Surface texture influences cellular response to implants, implant wear, and fixation, yet measurement and reporting of surface texture can be confusing and ambiguous. Seven specimens of widely different surface textures were submitted to three internationally renowned laboratories for surface texture characterization. The specimens were from dental implants, orthopedic implants, and femoral heads. Areas to be measured were clearly marked; simplified instructions were supplied but specific measurement parameters were not requested. Techniques used included contact profilometry, two- and three-dimensional laser profilometry, and atomic force microscopy. Four to thirteen parameters were reported, 2D or 3D, including R(a) or S(a); only three were common to all centers. The results varied by as much as +/-300-1000%, depending on technique and surface type. Some surfaces were not measurable by some techniques. One dental implant surface was reported with R(a) of 0.17, 0.85, 1.9, and 4.4 microm. The CoCr femoral head ranged from an R(a) of 0.011 to 0.10 microm; the zirconia head from 0.006 to 0.05 microm. Similar variability was reported for the other parameters. Useful surface texture characterization requires reporting of all measurement parameters. Comparisons between studies may be compromised if differences in technique are not considered.
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| 8. |
- Rosén, Bengt Göran, et al.
(författare)
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Topographical characterisation of artificial femoral heads : a Benchmarking study
- 2004
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Ingår i: Wear. - : Elsevier. - 0043-1648 .- 1873-2577. ; 257:12, s. 1275-1280
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Tidskriftsartikel (refereegranskat)abstract
- The main functional demands on artificial joints are that they last more than 20 years. This means optimising the friction coefficient to minimise forces transmitted to the surrounding bone and the wear of the contacting surfaces. Surface roughness has an important influence on friction and wear. Traditionally, the 2D Ra-parameter has been the preferred way to characterise the joint's topography. Today ongoing development of 3D techniques are available for the research, and the aim of the present paper is to highlight the importance and possibilities using high-resolution 3D atomic force microscope ( AFM) and the optical phase-shifting interferometer for texture characterisation of eight commercially available femoral heads. The results show a significant variation of topography and surface-lay for the different femoral heads in the study. The variation and difference between heads were further underlined by the use of different characterisation techniques and measuring strategy. Results highlight the importance of the selection of measurement strategy, parameters, instrumentation, and scale of measurement in order properly to characterise the femoral heads in this study.
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