| 1. |
- Chowdhary, Ramesh, et al.
(författare)
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Evaluation of stress pattern generated through various thread designs of dental implants loaded in a condition of immediately after placement and on osseointegration : an FEA study
- 2013
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Ingår i: Implant Dentistry. - : Lippincott Williams & Wilkins. - 1056-6163 .- 1538-2982. ; 22:1, s. 91-96
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To determine the stress pattern generated through various thread design in experimental simulation models, when loaded immediately after placement and after osseointegration. METHODS: Three-dimensional (3D) models were designed using CATIA, computer-aided design modeling software. The study was planned in 2 stages. Eight 2D models were constructed of different thread forms, one set with frictionless and other with bonded for bone to implant interface and loaded vertically with 100 N. In Stage II, 6 3D models of the different threads embedded in the cortical bone were constructed and loaded vertically and obliquely. RESULTS: In 2D models, the von Mises stress concentrated at the crest in the bonded connection thread designs. The stress levels were in the range of 7 to 13 MPa. In the frictional implant bone interface, the thread designs had a clear effect on the stress levels in the bone. In the 3D analysis, the complete implant design affected the stress levels. CONCLUSIONS: The thread design affects the magnitude of the stress peak in the bone more effectively in immediately loaded (frictionless) implants than the osseointegrated (bonded) implants. Maximum stress was observed at the first thread in most of the osseointegrated implants.
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| 2. |
- Galli, Silvia, et al.
(författare)
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Surface Characterization and Clinical Review of Two Commercially Available Implants
- 2013
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Ingår i: Implant dentistry. - : Lamy, Wolters Kluwer. - 1538-2982 .- 1056-6163. ; 22:5, s. 507-518
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Tidskriftsartikel (refereegranskat)abstract
- Purpose:To characterize topographically and chemically the surfaces of 2 commercially available implants. Furthermore, to gather an overview of the clinical results of these implant systems.Materials and Methods:Two commercially available oral implants were analyzed using optical interferometry, scanning electron microscopy, and energy dispersive spectroscopy. In addition, a literature search for all the clinical articles on the same implants was performed.Results:No significant differences of topographical parameters were found between the 2 implants, except for the hybrid parameter Sdr presenting significant higher values for the Ankylos implants. Both surfaces had a homogenous microporosity. At higher magnifications of scanning electron microscope images, evenly distributed nanostructures (approximately 10 nm) were visible. Chemically, mainly titanium, oxygen and carbon were detected. Fifty-six clinical articles were included for the review. The implant survival rates (minimum follow-up: 5 years) ranged between 87.7% and 100%.Conclusions:The examined commercially available implants showed a moderately rough surface, with a homogenous microporosity. Nanofeatures were detected on the surface of both implants. The clinical performances of these implants were comparable to that of other commercialized implant systems.
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| 3. |
- Jimbo, Ryo, et al.
(författare)
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Histomorphometry and bone mechanical property evolution around different implant systems at early healing stages : an experimental study in dogs
- 2013
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Ingår i: Implant Dentistry. - : Lamy, Wolters Kluwer. - 1056-6163 .- 1538-2982. ; 22:6, s. 596-603
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Commercial implants differ at macro-, micro-, and nanolevels, which makes it difficult to distinguish their effect on osseointegration. The aim of this study was to evaluate the early integration of 5 commercially available implants (Astra OsseoSpeed, Straumann SLA, Intra-Lock Blossom Ossean, Nobel Active, and OsseoFix) by histomorphometry and nanoindentation. MATERIALS AND METHODS: Implants were installed in the tibiae of 18 beagle dogs. Samples were retrieved at 1, 3, and 6 weeks (n = 6 for each time point) and were histologically and nanomechanically evaluated. RESULTS: The results presented that both time (P < 0.01) and implant system and time interaction (P < 0.02) significantly affected the bone-to-implant contact (BIC). At 1 week, the different groups presented statistically different outcomes. No significant changes in BIC were noted thereafter. There were no significant differences in rank elastic modulus (E) or in rank hardness (H) for time (E: P > 0.80; H: P > 0.75) or implant system (E: P > 0.90; H: P > 0.85). CONCLUSIONS: The effect of different implant designs on osseointegration was evident especially at early stages of bone healing.
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| 4. |
- Vandeweghe, Stefan, et al.
(författare)
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Comparison of histological and three-dimensional characteristics of porous titanium granules and deproteinized bovine particulate grafts used for sinus floor augmentation in humans : a pilot study
- 2013
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Ingår i: Implant Dentistry. - : Lamy, Wolters Kluwer. - 1056-6163 .- 1538-2982. ; 22:4, s. 339-343
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Slow-resorbing deproteinized bovine bone grafts have presented high success rates when used for sinus augmentation. However, histologic evaluation shows that this material is eventually excreted as a result of a foreign body reaction. The purpose of this study was to compare and to evaluate the performance of a recently introduced particulate porous graft material, consisting of pure titanium granule (PTG) to the deproteinized bovine bone grafts, when used as a sinus augmentation material. MATERIALS AND METHODS: To understand the histological aspects of PTG, deproteinized bovine particulates (Bio-Oss) and PTG were placed contralaterally as sinus grafting materials in 2 patients. After 9 months, biopsies were performed for histologic and 3-dimensional analysis. RESULTS: Both materials were in contact with newly formed bone. The Bio-Oss showed signs of foreign body reaction. In contrast, bone filled the space between the single PTG particulates, and no foreign body reaction was observed. CONCLUSIONS: From a bone formation perspective, PTG grafts were comparable with the commonly used Bio-Oss grafts and may be regarded as a possible alternative for permanent grafting in sinus augmentation.
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