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Natural Bone Mineral (natural + bone_mineral)
Selected AbstractsHistological assessment of augmented jaw bone utilizing a new collagen barrier membrane compared to a standard barrier membrane to protect a granular bone substitute materialCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2002A randomized clinical trial Abstract: Successful bone augmentation requires predictable space maintenance and adequate exclusion of those cells that lack osteogenetic potential from the defect area. Natural bone mineral is considered to be osteoconductive and is used as space maker in combination with membrane barrier techniques. The aim of this study was to compare qualitative histological results achieved by using deproteinized bovine bone mineral (DBBM) as a space maintainer and a new collagen barrier (OssixÔ, test group) vs. the same bone substitute and the standard e-PTFE membrane (Gore-Tex®, control group). Twenty-eight patients were randomly assigned to the test or the control group. Seven months after augmentation procedures, biopsies were obtained at reentry and were analysed histomorphometrically. In all, 14 specimens of group I (test group, OssixÔ) and 13 specimens of group II (controls, PTFE-membranes) showed close qualitative similarity of their histologies. Histomorphometrically, total mineralized bone area was 42% ± 18% in group I vs. 39% ± 15% in group II. The unmineralized tissue area was 44% ± 15% vs. 46% ± 12% and the area of DBBM remnants 14% ± 9% and 15% ± 12%, respectively. The differences were statistically nonsignificant (Mann,Whitney test). The occurrence of barrier exposure did not interfere with the histological outcome either in the test or in the control group. The new collagen barrier combined with the DBBM provided qualitative bone regeneration comparable to the standard e-PTFE material combined with the same mineral. [source] Novel Magnetic Hydroxyapatite Nanoparticles as Non-Viral Vectors for the Glial Cell Line-Derived Neurotrophic Factor GeneADVANCED FUNCTIONAL MATERIALS, Issue 1 2010Hsi-Chin Wu Abstract Nanoparticles (NPs) of synthetic hydroxyapatite (Hap) and natural bone mineral (NBM) are rendered magnetic by treatment with iron ions using a wet-chemical process. The magnetic NPs (mNPs), which are about 300,nm in diameter, display superparamagnetic properties in a superconducting quantum interference device, with a saturation magnetization of about 30,emu g,1. X-ray diffraction and transmission electron microscopy reveal that the magnetic properties of the NPs are the result of the hetero-epitaxial growth of magnetite on the Hap and NBM crystallites. The mNPs display a high binding affinity for plasmid DNA in contrast to magnetite NPs which do not bind the plasmid well. The mHap and mNBM NPs result in substantial increases in the transfection of rat marrow-derived mesenchymal stem cells with the gene for glial cell line-derived neurotrophic factor (GDNF), with magnetofection compared to transfection in the absence of a magnet. The amount of GDNF recovered in the medium approaches therapeutic levels despite the small amount of plasmid delivered by the NPs. [source] Enzyme Directed Templating of Artificial Bone MineralADVANCED MATERIALS, Issue 4 2009Erik D. Spoerke An artificial, in vitro biomineralization process that utilizes a nanofiber gel to as a substrate for biomimetic hydroxyapatite mineralization in three dimensions is presented. The system employs the natural enzyme alkaline phosphatase and a phosphorylated, anionic nanofiber gel matrix to template hydroxyapatite nanocrystals with size, shape, and crystallographic orientation resembling natural bone mineral. [source] Two-year clinical results following treatment of peri-implantitis lesions using a nanocrystalline hydroxyapatite or a natural bone mineral in combination with a collagen membraneJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2008Frank Schwarz Abstract Objectives: The aim of the present case series was to evaluate the 2-year results obtained following treatment of peri-implantitis lesions using either a nanocrystalline hydroxyapatite (NHA) or a natural bone mineral in combination with a collagen membrane (NBM+CM). Material and Methods: Twenty-two patients suffering from moderate peri-implantitis (n=22 intra-bony defects) were randomly treated with (i) access flap surgery (AFS) and the application of NHA, or with AFS and the application of NBM+CM. Clinical parameters were recorded at baseline and after 12, 18, and 24 months of non-submerged healing. Results: Two patients from the NHA group were excluded from the study due to severe pus formation at 12 months. At 24 months, both groups revealed clinically important probing depth (PD) reductions (NHA: 1.5±0.6 mm; NBM+CM: 2.4±0.8 mm) and clinical attachment level (CAL) gains (NHA: 1.0±0.4 mm; NBM+CM: 2.0±0.8 mm). However, these clinical improvements seemed to be better in the NBM+CM group (difference between groups: PD reduction: 0.9±0.2 mm; CAL gain: 1.0±0.3 mm). Conclusion: Both treatment procedures have shown efficacy over a period of 24 months, however, the application of NBM+CM may result in an improved outcome of healing. [source] Five-year results of a prospective, randomized, controlled study evaluating treatment of intra-bony defects with a natural bone mineral and GTRJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2007Anton Sculean Abstract Background: Treatment with a natural bone mineral (NBM) and a guided tissue regeneration (GTR) has been shown to promote periodontal regeneration. However, until now there are only very limited data on the long-term clinical results following this regenerative technique. Aim: To present the 5-year results of a prospective, randomized, controlled clinical study evaluating the treatment of deep intra-bony defects either with open flap debridement (OFD) and a combination of an NBM and GTR (test) or OFD alone (control). Methods: Nineteen patients diagnosed with advanced chronic periodontitis, and each of whom displayed one intra-bony defect, received randomly the test or the control treatment. Results were evaluated at baseline, at 1 and at 5 years following therapy. Results: No statistically significant differences in any of the investigated parameters were observed at baseline between the two groups. At 1 year after therapy, the test group showed a reduction in mean probing depth (PD) from 9.1±1.1 to 3.7±0.8 mm (p<0.001) and a change in mean clinical attachment level (CAL) from 10.4±1.3 to 6.4±1.2 mm (p<0.001). At 5 years, mean PD and CAL measured 4.3±0.8 and 6.7±1.6 mm, respectively. At 5 years, both PD and CAL were statistically significantly improved compared with baseline (p<0.001) without statistically significant differences between the 1- and 5-year results. In the control group, mean PD was reduced from 8.9±1.3 to 4.9±1.2 mm (p<0.001) and mean CAL changed from 10.6±1.4 to 8.8±1.5 mm (p<0.01). At 5 years, mean PD and CAL measured 5.6±1.1 and 9.1±1.3 mm, respectively, and were still statistically significantly improved compared with baseline (p<0.01). No statistically significant differences were found between the 1- and 5-year results. The test treatment, at both 1 and 5 years, yielded statistically significantly higher CAL gains than the control one (p<0.01). Compared with baseline, at 5 years a CAL gain of 3 mm was found in nine defects (90%) of the test group but in none of the defects treated with OFD alone. Conclusions: It was concluded that (i) treatment of intra-bony defects with OFD+NBM+GTR may result in significantly higher CAL gains than treatment with OFD, and (ii) the clinical results obtained after both treatments can be maintained over a period of 5 years. [source] Initial pattern of angiogenesis and bone formation following lateral ridge augmentation using rhPDGF and guided bone regeneration: an immunohistochemical study in dogsCLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2010Frank Schwarz Abstract Objectives: To evaluate (i) the effects of rhPDGF-BB on localized ridge augmentation using a natural bone mineral (NBM), and (ii) the influence of a collagen membrane (CM) on factor activity. Materials and methods: Chronic-type alveolar ridge defects (n=4 dogs) were randomly allocated in a split-mouth design as follows: upper jaw: NBM+rhPDGF-BB+CM (test) vs. NBM+rhPDGF-BB (control), and lower jaw: NBM+rhPDGF-BB+CM (test) vs. NBM+CM (control). After 3 weeks, dissected blocks were prepared for immunohistochemical (angiogenesis , TG) and histomorphometrical analysis [e.g. augmented area (AA), mineralized , (MT), non-mineralized tissue (NMT) (mm2)]. Results: Lower jaw: TG and mineralization of AA mainly originated from the defect borders. Test sites revealed a pronounced TG antigen reactivity and higher AA and MT values (mean and median). Upper jaw: control sites revealed a dislocation of AA in caudal direction, but also an improved vascularization in the peripheral wound area. While MT values (median) appeared to be comparable in both groups, AA, NMT, and NBM values (mean and median) tended to be higher at test sites. Conclusions: It was concluded that (i) rhPDGF-BB soak-loaded on NBM might have the potential to support bone formation at chronic-type lateral ridge defects, and (ii) the application of CM did not seem to interfere with the factor activity, but ensured a stabilization of the graft particles. To cited this article: Schwarz F, Ferrari D, Podolsky L, Mihatovic I, Becker J. Initial pattern of angiogenesis and bone formation following lateral ridge augmentation using rhPDGF and guided bone regeneration: an immunohistochemical study in dogs. Clin. Oral Impl. Res. 21, 2010; 90,99. [source] Use of a new cross-linked collagen membrane for the treatment of dehiscence-type defects at titanium implants: a prospective, randomized-controlled double-blinded clinical multicenter studyCLINICAL ORAL IMPLANTS RESEARCH, Issue 7 2009Jürgen Becker Abstract Objectives: The aim of the present randomized-controlled double-blinded clinical multicenter study was to assess the use of either a new cross-linked (VN) or a native collagen membrane (BG) for the treatment of dehiscence-type defects at titanium implants. Material and methods: A total of n=54 patients were recruited in four German university clinics. According to a parallel-groups design, dehiscence-type defects at titanium implants were filled with a natural bone mineral and randomly assigned to either VN or BG. Submerged sites were allowed to heal for 4 months. Primary (e.g., changes in defect length ,,DL, quality of newly formed tissue [0,4] , TQ) and secondary parameters (e.g., membrane exposure, tissue conditions at dehisced sites) were consecutively recorded. Results: Four patients were excluded due to an early wound infection (VN:3; BG:1), and one patient was lost during follow-up (VN). The mean ,DL was 3.0 ± 2.5 mm in the VN, and 1.94 ± 2.13 mm in the BG group. The assessment of TQ revealed comparable mean values in both groups (VN: 3.05 ± 1.66, BG: 3.46 ± 1.48). A significant correlation between membrane exposure and inflammation of the adjacent soft tissue was observed in the VN group. In both groups, the mean DL and TQ values were not significantly different at either non-exposed or exposed implant sites. Conclusion: The results of the present study have indicated that VN supported bone regeneration on a level non-inferior to BG. However, in case of a premature membrane exposure, cross-linking might impair soft-tissue healing or may even cause wound infections. [source] Lateral ridge augmentation using particulated or block bone substitutes biocoated with rhGDF-5 and rhBMP-2: an immunohistochemical study in dogsCLINICAL ORAL IMPLANTS RESEARCH, Issue 7 2008Frank Schwarz Abstract Objectives: The aim of the present study was to immunohistochemically evaluate lateral ridge augmentation using a particulated (BOG) or block (BOB) natural bone mineral biocoated with rhGDF-5 and rhBMP-2 in dogs. Materials and methods: Three standardized box-shaped defects were surgically created at the buccal aspect of the alveolar ridge in each quadrant of eight beagle dogs. After 2 months of healing, the chronic-type defects were randomly allocated in a split-mouth design to either (i) BOG or (ii) BOB biocoated with (a) rhGDF-5 or (b) rhBMP-2, respectively. Uncoated grafts served as controls. After 3 and 8 weeks, dissected blocks were prepared for immunohistochemical [osteocalcin (OC)] and histomorphometrical analysis [e.g. area (mm2) of new bone fill (BF), newly formed mineralized (MT) and non-mineralized tissue (NMT)]. Results: rhBMP-2 biocoated BOG revealed significantly highest BF and MT values at 3 (upper and lower jaws , UJ/LJ , compared with BOG) and 8 weeks (UJ , compared with rhGDF-5). Biocoating of BOB using both rhGDF-5 and rhBMP-2 resulted in significantly increased MT values at 8 weeks (UJ/LJ , compared with BOB). In all groups, NMT adjacent to BOG and BOB scaffolds revealed pronounced signs of an OC antigen reactivity. Conclusions: Within the limits of the present study, it was concluded that both rhGDF-5 and rhBMP-2 have shown efficacy; however, their bone regenerative effect was markedly influenced by the carrier. [source] | |||||||||||||