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- Suska, Felicia, 1974, et al.
(author)
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In vivo cytokine secretion and NF-kappaB activation around titanium and copper implants.
- 2005
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In: Biomaterials. - : Elsevier BV. - 0142-9612 .- 1878-5905. ; 26:5, s. 519-27
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Journal article (peer-reviewed)abstract
- The early biological response at titanium (Ti), copper (Cu)-coated Ti and sham sites was evaluated in an in vivo rat model. Material surface chemical and topographical properties were characterized using Auger electron spectroscopy, energy dispersive X-ray spectroscopy and interferometry, respectively. The number of leukocytes, cell types and cell viability (release of lactate dehydrogenase) were determined in the implant-interface exudate. The contents of activated nuclear transcription factor NF-kappaB, interleukin-6 (IL-6) and interleukin-10 (IL-10) were determined by enzyme linked immunosorbent assay. An increase in the number of leukocytes, in particular, polymorphonuclear leukocytes, was observed between 12 and 48 h around Cu. A marked decrease of exudate cell viability was found around Cu after 48 h. The total amounts of activated NF-kappaB after 12 h was highest in Ti exudates whereas after 48 h the highest amount of NF-kappaB was detected around Cu. The levels of cytokine IL-6 were consistently high around Cu at both time periods. No differences in IL-10 contents were detected, irrespective of material/sham and time. The results show that materials with different toxicity grades (titanium with low and copper with high toxicity) exhibit early differences in the activation of NF-kappaB, extracellular expression and secretion of mediators, causing major differences in inflammatory cell accumulation and death in vivo.
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| 2. |
- Thor, Andreas, et al.
(author)
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The role of whole blood in thrombin generation in contact with various titanium surfaces
- 2007
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In: Biomaterials. - : Elsevier BV. - 0142-9612 .- 1878-5905. ; 28:6, s. 966-74
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Journal article (peer-reviewed)abstract
- Understanding of the thrombotic response (activation of the intrinsic coagulation system followed by platelet activation) from blood components upon contact with a titanium dental implant is important and not fully understood. The aims of this study were to evaluate: (1) the thrombogenic response of whole blood, platelet-rich plasma (PRP) and platelet-poor plasma (PPP) in contact with a highly thrombogenic surface as titanium, (2) the thrombogenic response of clinically used surfaces as hydroxyapatite (HA), machined titanium (mTi), TiO2 grit-blasted titanium (TiOB) and fluoride ion-modified grit-blasted titanium (TiOB-F). An in vitro slide chamber model, furnished with heparin, was used in which whole blood, PRP or PPP came in contact with slides of the test surfaces. After incubation (60 min rotation at 22 rpm in a 37 degrees C water bath), blood/plasma was mixed with EDTA or citrate, further centrifuged at +4 degrees C (2200 g at 10 min). Finally, plasma was collected pending analysis. Whole blood in contact with Ti alloy resulted in the binding of platelets to the material surface and in the generation of thrombin-antithrombin (TAT) complexes. With whole blood TAT levels increased 1000-fold compared with PRP and PPP, in which both almost no increase of TAT could be detected. In addition, the platelet activation showed a similar pattern with a 15-fold higher release of beta-TG in whole blood. In the in vitro chamber model with the clinically relevant materials, the fluoride-modified surface (TiOB-F) showed pronounced TAT generation compared with TiOB, mTi and HA. Similar results were achieved for platelet consumption and activation markers of the intrinsic coagulation system. Taken together these results implicate first that whole blood is necessary for sufficient thrombin generation and platelet activation during placement of implants. Second, a fluoride ion modification seems to augment the thrombogenic properties of titanium.
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| 3. |
- Wennerberg, Ann, 1955, et al.
(author)
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Nanoporous TiO(3) Thin Film on Titanium Oral Implants for Enhanced Human Soft Tissue Adhesion: A Light and Electron Microscopy Study.
- 2011
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In: Clinical implant dentistry and related research. - : Wiley. - 1708-8208 .- 1523-0899.
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Journal article (peer-reviewed)abstract
- ABSTRACT Background: Previous experimental studies have demonstrated direct soft tissue attachment for nanoporous titanium dioxide (TiO(2)) thin film on implants, while implants without TiO(2) thin film have not shown this capability. Purpose: The aims were to evaluate and compare TiO(2) surface-modified experimental microimplants with unmodified microimplants with respect to tissue interaction of the human oral mucosa evaluated by light microscopy on ground sections and semithin sections and transmission electron microscopy on ultrathin sections, and to characterize the inflammatory response and the level of the marginal bone resorption. Materials and Methods: The study was a single-center, randomized, comparative, clinical investigation with intrasubject comparison of implants with and without TiO(2) thin film in 15 patients. Results: Two comparator microimplants showed mild erythema and expulsion of fluids. The surrounding tissues around all test implants were clinically healthy. The oral mucosa in contact with the abutment part of the microimplant was 72% for the test implants and 48% for the comparator implants, a statistically significant difference (p = .0268). No statistically significant difference was found in other histological variables. The marginal bone loss in 14 weeks was 0.5 mm for the stable test (n = 11) and 1.7 mm for the stable comparator implants (n = 9; p = .0248). Conclusions: The nanoporous TiO(2) surface modification has potential clinical benefits because of increased adherence of soft tissue and possible reduced bone resorption.
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