The effect of titanium plasmasprayed implants on trabecular bone healing in the goat

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Histological evaluation of different Ca-P sputter coatings implanted in goals

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A mechanical evaluation of TiO2-gritblasted and Ca-P magnetron sputter coated implants placed into the trabecular bone of the goat: part 1

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A histological evaluation of TiO2-gritblasted and Ca-P magnetron sputter coated implants placed into the trabecular bone of the goat: part 2

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The evaluation of Ca-P coatings in the animal experiment: the importance of the study design

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In vitro osteogenic potential of bone debris resulting from placement of titanium screw-type implants.

Contains fulltext : 69790.pdf (publisher's version ) (Closed access)OBJECTIVES: Histological sections of preclinical animal studies have shown that new bone formation around dental implants frequently contains debris derived from the original bone. Whether such debris by itself is osteogenic, i.e., can influence the process of new bone formation after implant placement, is still unknown. We therefore aim to investigate if such debris does have osteogenic potential. MATERIAL AND METHODS: To substantiate our hypothesis, we performed an in vitro study in which titanium screws were placed into animal bone, and immediately removed. Without additional treatment these were placed into a cell culture medium provided with beta-glycerophosphate. We used Von Kossa staining and scanning electron microscopy to examine calcifications on the surface of the implants. Additionally, total DNA analysis, alkaline phosphates activity, and calcium content were assessed on the screw surface. RESULTS: Light and electron microscopy revealed the increasing presence of calcified matter on the implant surface. DNA amounts doubled from days 1 to 6, while alkaline phosphatase activity and calcium content showed a pronounced increase over the entire incubation time. None of these phenomena occurred on the control samples in the same medium. CONCLUSIONS: From these results, we proved that bone debris, which arises from dental implant placement, and which is moved along by the inherent roughness of the implant, by itself has osteogenic potential

Validation of microfocus computed tomography in the evaluation of bone implant specimens.

Contains fulltext : 48247.pdf (publisher's version ) (Closed access)BACKGROUND: Microfocus computed tomography (muCT) is an emerging technique owing to its speed, full three-dimensional information, and nondestructive properties. PURPOSE: The aim of this study was to explore the efficacy of a muCT system (Philips HOMX 161, Philips Medical Systems GmbH, Hamburg, Germany) for visualization of the bone structure around screw-type titanium implants by comparing muCT images with their histologic homologues. MATERIALS AND METHODS: Eight screw-type titanium implants were placed in the femoral condyles of two goats. After the excised implant-bone specimens were embedded in resin, three-dimensional muCT of the excised implant and bone specimens was performed. Histologic sections were subsequently made. A total of 150 histologic sections were matched with muCT images. RESULTS: Bone trabeculae were clearly visible on the muCT scans. However, bone close to the implant or present in the apical surface features of the implant could not be detected. The overall matching between muCT scans (slices) and the histologic sections was 89%. CONCLUSION: Investigation of trabecular bone around titanium implants by muCT can be considered highly reliable for determining trabecular bone parameters, with the exception of measuring direct bone-to-implant contact

Effect of controlled early implant loading on bone healing and bone mass in guinea pigs, as assessed by micro-CT and histology.

Contains fulltext : 50109.pdf (publisher's version ) (Closed access)Without controlled loading, the failure of early loaded oral implants is higher than in delayed loading, unless loading regimens can be identified that stimulate bone formation. The purpose of this study was to investigate whether controlled early loading optimizes osseointegration. Six series of guinea pigs received percutaneous implants in both tibiae. One implant was stimulated, the contra-lateral served as the control. The strain rate amplitude varied from 1,620 to 12,000 microstrain s(-1). In vivo microfocus computed tomography (micro-CT) was used to study the peri-implant bone at three time points: 1 wk after implantation, but before starting stimulation (V1); 2 wk after stimulation (V2); and 4 wk after stimulation, after the guinea pigs were killed (PM). Bone implant contact and bone mass [BM (%) bone occupied area fraction] were analyzed. The implant failure was 5.9% (six control/one test). Although bone implant contact did not significantly differ, bone mass in the distal half peri-implant marrow cavity was significantly higher around test implants. Strain rate amplitude and the difference in bone mass between test and control implants were inversely correlated. A strain rate amplitude of 1,620 microstrain s(-1) in the cortical bone at a distance of 1.3 mm from the implant showed the highest effect. Based on these results, early loading did not negatively affect the implant outcome. On the contrary, an improved bone reaction in the marrow cavity around early loaded implants was achieved

Professor Dave Hansen

Professor Dave Hansen is caught in a candid image at Linfield College. He sits next to an unidentified man. Professor Hansen taught economics from 1969-2012. He also served as Vice-President for Student Services/Dean of Students from 1988-2010.https://digitalcommons.linfield.edu/lca_photos/1310/thumbnail.jp